Update all admin panels.

Admin panels will not contain better locales codding and easier-to-improve design.

Remove old and unused GUIs.

src/main/java/world/bentobox/challenges/panel/CommonPagedPanel.java

@@ -0,0 +1,183 @@
+//
+// Created by BONNe
+// Copyright - 2021
+//
+
+
+package world.bentobox.challenges.panel;
+
+
+import org.bukkit.Material;
+import org.bukkit.World;
+import org.bukkit.inventory.ItemStack;
+import org.eclipse.jdt.annotation.NonNull;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Function;
+
+import world.bentobox.bentobox.api.panels.PanelItem;
+import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
+import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
+import world.bentobox.bentobox.api.user.User;
+import world.bentobox.challenges.ChallengesAddon;
+import world.bentobox.challenges.utils.Constants;
+
+
+/**
+ * This panel implements common things for Paged pages.
+ */
+public abstract class CommonPagedPanel extends CommonPanel
+{
+    /**
+     * Instantiates a new Common paged panel.
+     *
+     * @param addon the addon
+     * @param user the user
+     * @param world the world
+     * @param topLabel the top label
+     * @param permissionPrefix the permission prefix
+     */
+    protected CommonPagedPanel(ChallengesAddon addon,
+        User user,
+        World world, String topLabel, String permissionPrefix)
+    {
+        super(addon, user, world, topLabel, permissionPrefix);
+    }
+
+
+    /**
+     * Instantiates a new Common paged panel.
+     *
+     * @param parentPanel the parent panel
+     */
+    protected CommonPagedPanel(@NonNull CommonPanel parentPanel)
+    {
+        super(parentPanel);
+    }
+
+
+    /**
+     * Populate elements.
+     *
+     * @param panelBuilder the panel builder
+     * @param objectList the object list
+     * @param buttonBuilder the button builder
+     */
+    protected void populateElements(PanelBuilder panelBuilder,
+        List<?> objectList,
+        Function<Object, PanelItem> buttonBuilder)
+    {
+        final int MAX_ELEMENTS = 21;
+        final int size = objectList.size();
+
+        if (this.pageIndex < 0)
+        {
+            this.pageIndex = size / MAX_ELEMENTS;
+        }
+        else if (this.pageIndex > (size / MAX_ELEMENTS))
+        {
+            this.pageIndex = 0;
+        }
+
+        int objectIndex = MAX_ELEMENTS * this.pageIndex;
+
+        // I want first row to be only for navigation and return button.
+        int index = 10;
+
+        while (objectIndex < ((this.pageIndex + 1) * MAX_ELEMENTS) &&
+            objectIndex < size &&
+            index < 36)
+        {
+            if (!panelBuilder.slotOccupied(index))
+            {
+                panelBuilder.item(index, buttonBuilder.apply(objectList.get(objectIndex++)));
+            }
+
+            index++;
+        }
+
+        if (size > MAX_ELEMENTS && !(1.0 * size / MAX_ELEMENTS <= this.pageIndex + 1))
+        {
+            panelBuilder.item(26, this.getButton(CommonButtons.NEXT));
+
+        }
+
+        if (this.pageIndex > 0)
+        {
+            panelBuilder.item(18, this.getButton(CommonButtons.PREVIOUS));
+        }
+    }
+
+
+    /**
+     * This method returns PanelItem that represents given Button.
+     * @param button Button that must be returned.
+     * @return PanelItem with requested functionality.
+     */
+    protected PanelItem getButton(CommonButtons button)
+    {
+        final String reference = Constants.BUTTON + button.name().toLowerCase() + ".";
+
+        final String name = this.user.getTranslation(reference + "name");
+        final List<String> description = new ArrayList<>(3);
+
+        ItemStack icon;
+        PanelItem.ClickHandler clickHandler;
+
+        if (button == CommonButtons.NEXT)
+        {
+            description.add(this.user.getTranslation(reference + "description",
+                Constants.NUMBER, String.valueOf(this.pageIndex + 2)));
+
+            icon = new ItemStack(Material.OAK_SIGN, this.pageIndex + 2);
+            clickHandler = (panel, user, clickType, slot) ->
+            {
+                this.pageIndex++;
+                this.build();
+                return true;
+            };
+        }
+        else if (button == CommonButtons.PREVIOUS)
+        {
+            description.add(this.user.getTranslation(reference + "description",
+                Constants.NUMBER, String.valueOf(this.pageIndex)));
+
+            icon = new ItemStack(Material.OAK_SIGN, Math.max(1, this.pageIndex));
+            clickHandler = (panel, user, clickType, slot) ->
+            {
+                this.pageIndex--;
+                this.build();
+                return true;
+            };
+        }
+        else
+        {
+            icon = new ItemStack(Material.PAPER);
+            clickHandler = null;
+        }
+
+        return new PanelItemBuilder().
+            icon(icon).
+            name(name).
+            description(description).
+            clickHandler(clickHandler).
+            build();
+    }
+
+
+    /**
+     * Next and Previous Buttons.
+     */
+    private enum CommonButtons
+    {
+        NEXT,
+        PREVIOUS
+    }
+
+
+    /**
+     * Current page index.
+     */
+    private int pageIndex;
+}

src/main/java/world/bentobox/challenges/panel/ConversationUtils.java

@@ -0,0 +1,558 @@
+//
+// Created by BONNe
+// Copyright - 2020
+//
+
+
+package world.bentobox.challenges.panel;
+
+
+import org.apache.commons.lang.ArrayUtils;
+import org.bukkit.ChatColor;
+import org.bukkit.conversations.*;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Consumer;
+import java.util.function.Function;
+
+import world.bentobox.bentobox.BentoBox;
+import world.bentobox.bentobox.api.user.User;
+import world.bentobox.challenges.utils.Constants;
+import world.bentobox.challenges.utils.Utils;
+
+
+public class ConversationUtils
+{
+    // ---------------------------------------------------------------------
+    // Section: Conversation API implementation
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * This method will close opened gui and writes question in chat. After players answers on question in chat, message
+     * will trigger consumer and gui will reopen. Success and fail messages can be implemented like that, as user's chat
+     * options are disabled while it is in conversation.
+     *
+     * @param consumer Consumer that accepts player output text.
+     * @param question Message that will be displayed in chat when player triggers conversion.
+     * @param successMessage Message that will be displayed on successful operation.
+     * @param user User who is targeted with current confirmation.
+     */
+    public static void createConfirmation(Consumer<Boolean> consumer,
+            User user,
+            @NotNull String question,
+            @Nullable String successMessage)
+    {
+        ValidatingPrompt confirmationPrompt = new ValidatingPrompt()
+        {
+            /**
+             * Is input valid boolean.
+             *
+             * @param context the context
+             * @param input the input
+             * @return the boolean
+             */
+            @Override
+            protected boolean isInputValid(@NotNull ConversationContext context, @NotNull String input)
+            {
+                // Get valid strings from translations
+                String validEntry = user.getTranslation(Constants.CONVERSATIONS + "confirm-string") +
+                        "," + user.getTranslation(Constants.CONVERSATIONS + "deny-string") +
+                        "," + user.getTranslation(Constants.CONVERSATIONS + "exit-string") +
+                        "," + user.getTranslation(Constants.CONVERSATIONS + "cancel-string");
+
+                // Split and check if they exist in valid entries.
+                String[] accepted = validEntry.toLowerCase().replaceAll("\\s", "").split(",");
+                return ArrayUtils.contains(accepted, input.toLowerCase());
+            }
+
+
+            /**
+             * Accept validated input prompt.
+             *
+             * @param context the context
+             * @param input the input
+             * @return the prompt
+             */
+            @Override
+            @Nullable
+            protected Prompt acceptValidatedInput(@NotNull ConversationContext context, @NotNull String input)
+            {
+                String validEntry = user.getTranslation(Constants.CONVERSATIONS + "confirm-string").toLowerCase();
+
+                if (ArrayUtils.contains(validEntry.replaceAll("\\s", "").split(","), input.toLowerCase()))
+                {
+                    // Add answer to consumer.
+                    consumer.accept(true);
+                    // Return message about success.
+                    return ConversationUtils.endMessagePrompt(successMessage);
+                }
+                else
+                {
+                    // Add answer to consumer.
+                    consumer.accept(false);
+
+                    // Return message about failed operation.
+                    return ConversationUtils.endMessagePrompt(
+                            user.getTranslation(Constants.CONVERSATIONS + "cancelled"));
+                }
+            }
+
+
+            /**
+             * @see Prompt#getPromptText(ConversationContext)
+             */
+            @Override
+            public @NotNull String getPromptText(@NotNull ConversationContext conversationContext)
+            {
+                // Close input GUI.
+                user.closeInventory();
+                // There are no editable message. Just return question.
+                return question;
+            }
+        };
+
+        new ConversationFactory(BentoBox.getInstance()).
+            withPrefix(context -> user.getTranslation(Constants.CONVERSATIONS + "prefix")).
+            withFirstPrompt(confirmationPrompt).
+            withLocalEcho(false).
+            withTimeout(90).
+            buildConversation(user.getPlayer()).
+            begin();
+    }
+
+
+    /**
+     * This method will close opened gui and writes question in chat. After players answers on question in chat, message
+     * will trigger consumer and gui will reopen. Be aware, consumer does not return (and validate) sanitized value,
+     * while sanitization is done in failure for better informing. Proper implementation would be with adding new
+     * consumer for failure message.
+     *
+     * @param consumer Consumer that accepts player output text.
+     * @param validation Function that validates if input value is acceptable.
+     * @param question Message that will be displayed in chat when player triggers conversion.
+     * @param failTranslationLocation Message that will be displayed on failed operation.
+     * @param user User who is targeted with current confirmation.
+     */
+    public static void createIDStringInput(Consumer<String> consumer,
+            Function<String, Boolean> validation,
+            User user,
+            @NotNull String question,
+            @Nullable String successMessage,
+            @Nullable String failTranslationLocation)
+    {
+        ValidatingPrompt validatingPrompt = new ValidatingPrompt()
+        {
+            /**
+             * Gets the text to display to the user when
+             * this prompt is first presented.
+             *
+             * @param context Context information about the
+             * conversation.
+             * @return The text to display.
+             */
+            @Override
+            public String getPromptText(ConversationContext context)
+            {
+                // Close input GUI.
+                user.closeInventory();
+
+                // There are no editable message. Just return question.
+                return question;
+            }
+
+
+            /**
+             * Override this method to check the validity of
+             * the player's input.
+             *
+             * @param context Context information about the
+             * conversation.
+             * @param input The player's raw console input.
+             * @return True or false depending on the
+             * validity of the input.
+             */
+            @Override
+            protected boolean isInputValid(ConversationContext context, String input)
+            {
+                return validation.apply(input);
+            }
+
+
+            /**
+             * Optionally override this method to
+             * display an additional message if the
+             * user enters an invalid input.
+             *
+             * @param context Context information
+             * about the conversation.
+             * @param invalidInput The invalid input
+             * provided by the user.
+             * @return A message explaining how to
+             * correct the input.
+             */
+            @Override
+            protected String getFailedValidationText(ConversationContext context,
+                    String invalidInput)
+            {
+                return user.getTranslation(failTranslationLocation,
+                        Constants.ID,
+                        Utils.sanitizeInput(invalidInput));
+            }
+
+
+            /**
+             * Override this method to accept and processes
+             * the validated input from the user. Using the
+             * input, the next Prompt in the prompt graph
+             * should be returned.
+             *
+             * @param context Context information about the
+             * conversation.
+             * @param input The validated input text from
+             * the user.
+             * @return The next Prompt in the prompt graph.
+             */
+            @Override
+            protected Prompt acceptValidatedInput(ConversationContext context, String input)
+            {
+                // Add answer to consumer.
+                consumer.accept(input);
+                // Send message that it is accepted.
+                return ConversationUtils.endMessagePrompt(successMessage);
+            }
+        };
+
+        new ConversationFactory(BentoBox.getInstance()).
+            withPrefix(context -> user.getTranslation(Constants.CONVERSATIONS + "prefix")).
+            withFirstPrompt(validatingPrompt).
+            withLocalEcho(false).
+            withTimeout(90).
+            // On cancel conversation will be closed.
+            withEscapeSequence(user.getTranslation(Constants.CONVERSATIONS + "cancel-string")).
+            // Use null value in consumer to detect if user has abandoned conversation.
+            addConversationAbandonedListener(ConversationUtils.getAbandonListener(consumer, user)).
+            buildConversation(user.getPlayer()).
+            begin();
+    }
+
+
+    /**
+     * This method will close opened gui and writes inputText in chat. After players answers on inputText in chat,
+     * message will trigger consumer and gui will reopen.
+     *
+     * @param consumer Consumer that accepts player output text.
+     * @param question Message that will be displayed in chat when player triggers conversion.
+     */
+    public static void createNumericInput(Consumer<Number> consumer,
+            @NotNull User user,
+            @NotNull String question,
+            Number minValue,
+            Number maxValue)
+    {
+        // Create NumericPromt instance that will validate and process input.
+        NumericPrompt numberPrompt = new NumericPrompt()
+        {
+            /**
+             * Override this method to perform some action
+             * with the user's integer response.
+             *
+             * @param context Context information about the
+             * conversation.
+             * @param input The user's response as a {@link
+             * Number}.
+             * @return The next {@link Prompt} in the prompt
+             * graph.
+             */
+            @Override
+            protected Prompt acceptValidatedInput(ConversationContext context, Number input)
+            {
+                // Add answer to consumer.
+                consumer.accept(input);
+                // End conversation
+                return Prompt.END_OF_CONVERSATION;
+            }
+
+
+            /**
+             * Override this method to do further validation on the numeric player
+             * input after the input has been determined to actually be a number.
+             *
+             * @param context Context information about the conversation.
+             * @param input The number the player provided.
+             * @return The validity of the player's input.
+             */
+            @Override
+            protected boolean isNumberValid(ConversationContext context, Number input)
+            {
+                return input.doubleValue() >= minValue.doubleValue() &&
+                        input.doubleValue() <= maxValue.doubleValue();
+            }
+
+
+            /**
+             * Optionally override this method to display an additional message if the
+             * user enters an invalid number.
+             *
+             * @param context Context information about the conversation.
+             * @param invalidInput The invalid input provided by the user.
+             * @return A message explaining how to correct the input.
+             */
+            @Override
+            protected String getInputNotNumericText(ConversationContext context, String invalidInput)
+            {
+                return user.getTranslation(Constants.CONVERSATIONS + "numeric-only", Constants.VALUE, invalidInput);
+            }
+
+
+            /**
+             * Optionally override this method to display an additional message if the
+             * user enters an invalid numeric input.
+             *
+             * @param context Context information about the conversation.
+             * @param invalidInput The invalid input provided by the user.
+             * @return A message explaining how to correct the input.
+             */
+            @Override
+            protected String getFailedValidationText(ConversationContext context, Number invalidInput)
+            {
+                return user.getTranslation(Constants.CONVERSATIONS + "not-valid-value",
+                        Constants.VALUE, invalidInput.toString(),
+                        Constants.MIN, Double.toString(minValue.doubleValue()),
+                        Constants.MAX, Double.toString(maxValue.doubleValue()));
+            }
+
+
+            /**
+             * @see Prompt#getPromptText(ConversationContext)
+             */
+            @Override
+            public String getPromptText(ConversationContext conversationContext)
+            {
+                // Close input GUI.
+                user.closeInventory();
+                // There are no editable message. Just return question.
+                return question;
+            }
+        };
+
+        // Init conversation api.
+        new ConversationFactory(BentoBox.getInstance()).
+            withPrefix(context -> user.getTranslation(Constants.CONVERSATIONS + "prefix")).
+            withFirstPrompt(numberPrompt).
+            withLocalEcho(false).
+            withTimeout(90).
+            withEscapeSequence(user.getTranslation(Constants.CONVERSATIONS + "cancel-string")).
+            // Use null value in consumer to detect if user has abandoned conversation.
+            addConversationAbandonedListener(ConversationUtils.getAbandonListener(consumer, user)).
+            buildConversation(user.getPlayer()).
+            begin();
+    }
+
+
+    /**
+     * This method will close opened gui and writes question in chat. After players answers on question in chat, message
+     * will trigger consumer and gui will reopen. Be aware, consumer does not return (and validate) sanitized value,
+     * while sanitization is done in failure for better informing. Proper implementation would be with adding new
+     * consumer for failure message.
+     *
+     * @param consumer Consumer that accepts player output text.
+     * @param question Message that will be displayed in chat when player triggers conversion.
+     * @param user User who is targeted with current confirmation.
+     */
+    public static void createStringListInput(Consumer<List<String>> consumer,
+            User user,
+            @NotNull String question,
+            @NotNull String successMessage)
+    {
+        final String SESSION_CONSTANT = Constants.CONVERSATIONS + user.getUniqueId();
+
+        // Successful message about completing.
+        MessagePrompt messagePrompt = new MessagePrompt()
+        {
+            @Override
+            public @NotNull String getPromptText(@NotNull ConversationContext context)
+            {
+                List<String> description = (List<String>) context.getSessionData(SESSION_CONSTANT);
+
+                if (description != null)
+                {
+                    consumer.accept(description);
+                    return successMessage;
+                }
+                else
+                {
+                    return user.getTranslation(Constants.CONVERSATIONS + "cancelled");
+                }
+            }
+
+
+            @Override
+            protected @Nullable Prompt getNextPrompt(@NotNull ConversationContext context)
+            {
+                return Prompt.END_OF_CONVERSATION;
+            }
+        };
+
+        // Text input message.
+        StringPrompt stringPrompt = new StringPrompt()
+        {
+            @Override
+            public @NotNull String getPromptText(@NotNull ConversationContext context)
+            {
+                user.closeInventory();
+
+                if (context.getSessionData(SESSION_CONSTANT) != null)
+                {
+                    StringBuilder sb = new StringBuilder();
+                    sb.append(user.getTranslation(Constants.CONVERSATIONS + "written-text"));
+                    sb.append(System.getProperty("line.separator"));
+
+                    for (String line : ((List<String>) context.getSessionData(SESSION_CONSTANT)))
+                    {
+                        sb.append(line);
+                        sb.append(System.getProperty("line.separator"));
+                    }
+
+                    return sb.toString();
+                }
+
+                return question;
+            }
+
+
+            @Override
+            public @Nullable Prompt acceptInput(@NotNull ConversationContext context, @Nullable String input)
+            {
+                String[] exit = user.getTranslation(Constants.CONVERSATIONS + "exit-string").
+                        toLowerCase().replaceAll("\\s", "").
+                        split(",");
+
+                if (input != null && ArrayUtils.contains(exit, input.toLowerCase()))
+                {
+                    return messagePrompt;
+                }
+
+                List<String> desc = new ArrayList<>();
+
+                if (context.getSessionData(SESSION_CONSTANT) != null)
+                {
+                    desc = ((List<String>) context.getSessionData(SESSION_CONSTANT));
+                }
+                if (input != null) {
+                    desc.add(ChatColor.translateAlternateColorCodes('&', input));
+                }
+                context.setSessionData(SESSION_CONSTANT, desc);
+                return this;
+            }
+        };
+
+        new ConversationFactory(BentoBox.getInstance()).
+            withPrefix(context -> user.getTranslation(Constants.CONVERSATIONS + "prefix")).
+            withFirstPrompt(stringPrompt).
+            withModality(true).
+            withLocalEcho(false).
+            withTimeout(90).
+            withEscapeSequence(user.getTranslation(Constants.CONVERSATIONS + "cancel-string")).
+            addConversationAbandonedListener(ConversationUtils.getAbandonListener(consumer, user)).
+            buildConversation(user.getPlayer()).
+            begin();
+    }
+
+
+    /**
+     * This method will close opened gui and writes question in chat. After players answers on question in chat, message
+     * will trigger consumer and gui will reopen.
+     *
+     * @param consumer Consumer that accepts player output text.
+     * @param question Message that will be displayed in chat when player triggers conversion.
+     * @param user User who is targeted with current confirmation.
+     */
+    public static void createStringInput(Consumer<String> consumer,
+            User user,
+            @NotNull String question,
+            @Nullable String successMessage)
+    {
+        // Text input message.
+        StringPrompt stringPrompt = new StringPrompt()
+        {
+            @Override
+            public @NotNull String getPromptText(@NotNull ConversationContext context)
+            {
+                user.closeInventory();
+                return question;
+            }
+
+
+            @Override
+            public @NotNull Prompt acceptInput(@NotNull ConversationContext context, @Nullable String input)
+            {
+                consumer.accept(input);
+                return ConversationUtils.endMessagePrompt(successMessage);
+            }
+        };
+
+        new ConversationFactory(BentoBox.getInstance()).
+            withPrefix(context -> user.getTranslation(Constants.CONVERSATIONS + "prefix")).
+            withFirstPrompt(stringPrompt).
+            // On cancel conversation will be closed.
+            withLocalEcho(false).
+            withTimeout(90).
+            withEscapeSequence(user.getTranslation(Constants.CONVERSATIONS + "cancel-string")).
+            // Use null value in consumer to detect if user has abandoned conversation.
+            addConversationAbandonedListener(ConversationUtils.getAbandonListener(consumer, user)).
+            buildConversation(user.getPlayer()).
+            begin();
+    }
+
+
+    /**
+     * This is just a simple end message prompt that displays requested message.
+     *
+     * @param message Message that will be displayed.
+     * @return MessagePrompt that displays given message and exists from conversation.
+     */
+    private static MessagePrompt endMessagePrompt(@Nullable String message)
+    {
+        return new MessagePrompt()
+        {
+            @Override
+            public @NotNull String getPromptText(@NotNull ConversationContext context)
+            {
+                return message == null ? "" : message;
+            }
+
+
+            @Override
+            protected @Nullable Prompt getNextPrompt(@NotNull ConversationContext context)
+            {
+                return Prompt.END_OF_CONVERSATION;
+            }
+        };
+    }
+
+
+    /**
+     * This method creates and returns abandon listener for every conversation.
+     *
+     * @param consumer Consumer which must return null value.
+     * @param user User who was using conversation.
+     * @return ConversationAbandonedListener instance.
+     */
+    private static ConversationAbandonedListener getAbandonListener(Consumer<?> consumer, User user)
+    {
+        return abandonedEvent ->
+        {
+            if (!abandonedEvent.gracefulExit())
+            {
+                consumer.accept(null);
+                // send cancell message
+                abandonedEvent.getContext().getForWhom().sendRawMessage(
+                        user.getTranslation(Constants.CONVERSATIONS + "prefix") +
+                        user.getTranslation(Constants.CONVERSATIONS + "cancelled"));
+            }
+        };
+    }
+}

src/main/java/world/bentobox/challenges/panel/GameModesGUI.java

@@ -1,143 +0,0 @@
-package world.bentobox.challenges.panel;
-
-
-import java.util.List;
-import java.util.Optional;
-
-import org.bukkit.Material;
-import org.bukkit.World;
-
-import world.bentobox.bentobox.api.addons.GameModeAddon;
-import world.bentobox.bentobox.api.commands.CompositeCommand;
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.ChallengesAddon;
-import world.bentobox.challenges.utils.GuiUtils;
-
-
-/**
- * This class process GameModeGui opening.
- */
-public class GameModesGUI extends CommonGUI
-{
-    /**
-     * @param adminMode - boolean that indicate if Gui is in admin mode.
-     * @param gameModeAddons - List with GameModes where Challenges addon is integrated.
-     * @param addon Addon where panel operates.
-     * @param world World from which panel was created.
-     * @param user User who created panel.
-     * @param topLabel Command top label which creates panel (f.e. island or ai)
-     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
-
-     */
-    public GameModesGUI(ChallengesAddon addon,
-            World world,
-            User user,
-            String topLabel,
-            String permissionPrefix,
-            boolean adminMode,
-            List<GameModeAddon> gameModeAddons)
-    {
-        super(addon, world, user, topLabel, permissionPrefix);
-        this.adminMode = adminMode;
-        this.gameModeAddons = gameModeAddons;
-    }
-
-
-    @Override
-    public void build()
-    {
-        PanelBuilder panelBuilder = new PanelBuilder().user(this.user).
-                name("challenges.gui.title.game-modes");
-
-        GuiUtils.fillBorder(panelBuilder, this.adminMode ?
-                Material.BLACK_STAINED_GLASS_PANE :
-                    Material.BLUE_STAINED_GLASS_PANE);
-
-        int elementIndex;
-
-        if (this.gameModeAddons.size() < 8)
-        {
-            if (this.gameModeAddons.size() == 7)
-            {
-                elementIndex = 19;
-            }
-            else
-            {
-                elementIndex = 22 - this.gameModeAddons.size() / 2;
-            }
-        }
-        else
-        {
-            elementIndex = 10;
-        }
-
-        for (GameModeAddon gameModeAddon : this.gameModeAddons)
-        {
-            if (!panelBuilder.slotOccupied(elementIndex))
-            {
-                panelBuilder.item(elementIndex++, this.createGameModeIcon(gameModeAddon));
-            }
-            else
-            {
-                // Find first open slot
-                while (panelBuilder.slotOccupied(elementIndex))
-                {
-                    elementIndex++;
-                }
-            }
-        }
-
-        panelBuilder.build();
-    }
-
-
-    /**
-     * This method creates icon that will display given GameMode addon.
-     * @param gameModeAddon GameMode addon.
-     * @return PanelItem that acts as icon for given GameMode.
-     */
-    private PanelItem createGameModeIcon(GameModeAddon gameModeAddon)
-    {
-        return new PanelItemBuilder().
-                name(gameModeAddon.getDescription().getName()).
-                description(gameModeAddon.getDescription().getDescription()).
-                icon(Material.PAPER).
-                clickHandler((panel, user, clickType, slot) -> {
-                    Optional<CompositeCommand> command;
-
-                    if (this.adminMode)
-                    {
-                        command = gameModeAddon.getAdminCommand();
-                    }
-                    else
-                    {
-                        command = gameModeAddon.getPlayerCommand();
-                    }
-
-                    command.ifPresent(compositeCommand ->
-                    user.performCommand(compositeCommand.getTopLabel() + " challenges"));
-
-                    return true;
-                }).
-                build();
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Variables
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * List with game mode addons which must be showed in current GUI.
-     */
-    private List<GameModeAddon> gameModeAddons;
-
-    /**
-     * Stores if current GUI is in Admin Mode or not.
-     */
-    private boolean adminMode;
-}

src/main/java/world/bentobox/challenges/panel/admin/AdminGUI.java

@@ -1,736 +0,0 @@
-package world.bentobox.challenges.panel.admin;
-
-
-import java.util.Locale;
-import java.util.function.Consumer;
-import java.util.function.Function;
-
-import org.bukkit.Material;
-import org.bukkit.World;
-import org.bukkit.conversations.*;
-import org.bukkit.inventory.ItemStack;
-import org.eclipse.jdt.annotation.NonNull;
-
-import world.bentobox.bentobox.BentoBox;
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.ChallengesAddon;
-import world.bentobox.challenges.panel.CommonGUI;
-import world.bentobox.challenges.panel.util.ChallengeTypeGUI;
-import world.bentobox.challenges.panel.util.ConfirmationGUI;
-import world.bentobox.challenges.utils.GuiUtils;
-import world.bentobox.challenges.utils.Utils;
-import world.bentobox.challenges.web.WebManager;
-
-
-/**
- * This class contains Main
- */
-public class AdminGUI extends CommonGUI
-{
-    // ---------------------------------------------------------------------
-    // Section: Variables
-    // ---------------------------------------------------------------------
-
-    /**
-     * This boolean holds if import should overwrite existing challenges.
-     */
-    private boolean overwriteMode;
-
-    /**
-     * This indicate if Reset Challenges must work as reset all.
-     */
-    private boolean resetAllMode;
-
-	/**
-	 * This indicate if wipe button should clear all data, or only challenges.
-	 */
-	private boolean wipeAll;
-
-
-    // ---------------------------------------------------------------------
-    // Section: Enums
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * This enum contains all button variations. Just for cleaner code.
-     */
-    private enum Button
-    {
-        COMPLETE_USER_CHALLENGES,
-        RESET_USER_CHALLENGES,
-        ADD_CHALLENGE,
-        ADD_LEVEL,
-        EDIT_CHALLENGE,
-        EDIT_LEVEL,
-        DELETE_CHALLENGE,
-        DELETE_LEVEL,
-        EDIT_SETTINGS,
-        DEFAULT_IMPORT_CHALLENGES,
-        DEFAULT_EXPORT_CHALLENGES,
-        /**
-         * Allows to remove whole database
-         */
-        COMPLETE_WIPE,
-        /**
-         * Allows to remove only challenges and levels
-         */
-        CHALLENGE_WIPE,
-        /**
-         * Allows to remove only players data
-         */
-        USER_WIPE,
-        /**
-         * Allows to access Web Library
-         */
-        LIBRARY
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Constructor
-    // ---------------------------------------------------------------------
-
-    /**
-     * @param addon Addon where panel operates.
-     * @param world World from which panel was created.
-     * @param user User who created panel.
-     * @param topLabel Command top label which creates panel (f.e. island or ai)
-     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
-     */
-    public AdminGUI(ChallengesAddon addon,
-            World world,
-            User user,
-            String topLabel,
-            String permissionPrefix)
-    {
-        super(addon, world, user, topLabel, permissionPrefix);
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Methods
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * {@inheritDoc}
-     */
-    @Override
-    public void build()
-    {
-        PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(
-                this.user.getTranslation("challenges.gui.title.admin.gui-title"));
-
-        GuiUtils.fillBorder(panelBuilder);
-
-        panelBuilder.item(10, this.createButton(Button.COMPLETE_USER_CHALLENGES));
-        panelBuilder.item(19, this.createButton(Button.RESET_USER_CHALLENGES));
-
-        // Add All Player Data removal.
-        panelBuilder.item(28, this.createButton(Button.USER_WIPE));
-
-        // Add Challenges
-        panelBuilder.item(12, this.createButton(Button.ADD_CHALLENGE));
-        panelBuilder.item(13, this.createButton(Button.ADD_LEVEL));
-
-        // Edit Challenges
-        panelBuilder.item(21, this.createButton(Button.EDIT_CHALLENGE));
-        panelBuilder.item(22, this.createButton(Button.EDIT_LEVEL));
-
-        // Remove Challenges
-        panelBuilder.item(30, this.createButton(Button.DELETE_CHALLENGE));
-        panelBuilder.item(31, this.createButton(Button.DELETE_LEVEL));
-
-
-        // Import Challenges
-        panelBuilder.item(15, this.createButton(Button.DEFAULT_IMPORT_CHALLENGES));
-        panelBuilder.item(24, this.createButton(Button.LIBRARY));
-
-        // Not added as I do not think admins should use it. It still will be able via command.
-        //		panelBuilder.item(33, this.createButton(Button.DEFAULT_EXPORT_CHALLENGES));
-
-        // Edit Addon Settings
-        panelBuilder.item(16, this.createButton(Button.EDIT_SETTINGS));
-
-        // Button that deletes everything from challenges addon
-
-		if (this.wipeAll)
-		{
-			panelBuilder.item(34, this.createButton(Button.COMPLETE_WIPE));
-		}
-		else
-		{
-			panelBuilder.item(34, this.createButton(Button.CHALLENGE_WIPE));
-		}
-
-        panelBuilder.item(44, this.returnButton);
-
-        panelBuilder.build();
-    }
-
-
-    /**
-     * This method is used to create PanelItem for each button type.
-     * @param button Button which must be created.
-     * @return PanelItem with necessary functionality.
-     */
-    private PanelItem createButton(Button button)
-    {
-        ItemStack icon;
-        String name;
-        String description;
-        boolean glow;
-        PanelItem.ClickHandler clickHandler;
-
-        String permissionSuffix;
-
-        switch (button)
-        {
-        case COMPLETE_USER_CHALLENGES:
-            permissionSuffix = COMPLETE;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.complete");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.complete");
-            icon = new ItemStack(Material.WRITTEN_BOOK);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new ListUsersGUI(this.addon,
-                        this.world,
-                        this.user,
-                        ListUsersGUI.Mode.COMPLETE,
-                        this.topLabel,
-                        this.permissionPrefix,
-                        this).build();
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        case RESET_USER_CHALLENGES:
-            permissionSuffix = RESET;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.reset");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.reset");
-            icon = new ItemStack(Material.WRITABLE_BOOK);
-
-            glow = this.resetAllMode;
-
-            clickHandler = (panel, user, clickType, slot) -> {
-                if (clickType.isRightClick())
-                {
-                    this.resetAllMode = !this.resetAllMode;
-                    this.build();
-                }
-                else
-                {
-                    new ListUsersGUI(this.addon,
-                            this.world,
-                            this.user,
-                            this.resetAllMode ? ListUsersGUI.Mode.RESET_ALL : ListUsersGUI.Mode.RESET,
-                                    this.topLabel,
-                                    this.permissionPrefix,
-                                    this).build();
-                }
-
-                return true;
-            };
-
-            break;
-        case ADD_CHALLENGE:
-            permissionSuffix = ADD;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.create-challenge");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.create-challenge");
-            icon = new ItemStack(Material.BOOK);
-            clickHandler = (panel, user, clickType, slot) -> {
-
-                this.getNewUniqueID(challenge ->
-                    {
-                        if (challenge == null)
-                        {
-                            // Build Admin Gui if input is null.
-                            this.build();
-                        }
-                        else
-                        {
-                            String uniqueId = Utils.getGameMode(this.world) + "_" + challenge;
-
-                            ChallengeTypeGUI.open(user,
-                                this.addon.getChallengesSettings().getLoreLineLength(),
-                                (type, requirements) -> new EditChallengeGUI(this.addon,
-                                    this.world,
-                                    this.user,
-                                    this.addon.getChallengesManager().createChallenge(uniqueId, type, requirements),
-                                    this.topLabel,
-                                    this.permissionPrefix,
-                                    this).build());
-                        }
-                    },
-                    input -> {
-                        String uniqueId = Utils.getGameMode(this.world) + "_" + input;
-                        return !this.addon.getChallengesManager().containsChallenge(uniqueId);
-                    },
-                    this.user.getTranslation("challenges.gui.questions.admin.unique-id")
-                );
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        case ADD_LEVEL:
-            permissionSuffix = ADD;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.create-level");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.create-level");
-            icon = new ItemStack(Material.BOOK);
-            clickHandler = (panel, user, clickType, slot) -> {
-
-                this.getNewUniqueID(level ->
-                    {
-                        if (level == null)
-                        {
-                            // Build Admin Gui if input is null.
-                            this.build();
-                        }
-                        else
-                        {
-                            String newName = Utils.getGameMode(this.world) + "_" + level;
-
-                            new EditLevelGUI(this.addon,
-                                this.world,
-                                this.user,
-                                this.addon.getChallengesManager().createLevel(newName, this.world),
-                                this.topLabel,
-                                this.permissionPrefix,
-                                this).build();
-                        }
-                    },
-                    input -> {
-                        String newName = Utils.getGameMode(this.world) + "_" + input;
-                        return !this.addon.getChallengesManager().containsLevel(newName);
-                    },
-                    this.user.getTranslation("challenges.gui.questions.admin.unique-id")
-                );
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        case EDIT_CHALLENGE:
-            permissionSuffix = EDIT;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.edit-challenge");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.edit-challenge");
-            icon = new ItemStack(Material.ANVIL);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new ListChallengesGUI(this.addon,
-                        this.world,
-                        this.user,
-                        ListChallengesGUI.Mode.EDIT,
-                        this.topLabel,
-                        this.permissionPrefix,
-                        this).build();
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        case EDIT_LEVEL:
-        {
-            permissionSuffix = EDIT;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.edit-level");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.edit-level");
-            icon = new ItemStack(Material.ANVIL);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new ListLevelsGUI(this.addon,
-                        this.world,
-                        this.user,
-                        ListLevelsGUI.Mode.EDIT,
-                        this.topLabel,
-                        this.permissionPrefix,
-                        this).build();
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        }
-        case DELETE_CHALLENGE:
-        {
-            permissionSuffix = DELETE;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.delete-challenge");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.delete-challenge");
-            icon = new ItemStack(Material.LAVA_BUCKET);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new ListChallengesGUI(this.addon,
-                        this.world,
-                        this.user,
-                        ListChallengesGUI.Mode.DELETE,
-                        this.topLabel,
-                        this.permissionPrefix,
-                        this).build();
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        }
-        case DELETE_LEVEL:
-        {
-            permissionSuffix = DELETE;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.delete-level");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.delete-level");
-            icon = new ItemStack(Material.LAVA_BUCKET);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new ListLevelsGUI(this.addon,
-                        this.world,
-                        this.user,
-                        ListLevelsGUI.Mode.DELETE,
-                        this.topLabel,
-                        this.permissionPrefix,
-                        this).build();
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        }
-        case DEFAULT_IMPORT_CHALLENGES:
-        {
-            permissionSuffix = DEFAULT;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.default-import");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.default-import");
-            icon = new ItemStack(Material.HOPPER);
-            clickHandler = (panel, user, clickType, slot) -> {
-                // Run import command.
-                this.user.performCommand(this.topLabel + " " + CHALLENGES + " " + DEFAULT + " " + IMPORT);
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        }
-        case DEFAULT_EXPORT_CHALLENGES:
-        {
-            permissionSuffix = DEFAULT;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.default-export");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.default-export");
-            icon = new ItemStack(Material.HOPPER);
-            clickHandler = (panel, user, clickType, slot) -> {
-                if (clickType.isRightClick())
-                {
-                    this.overwriteMode = !this.overwriteMode;
-                    this.build();
-                }
-                else
-                {
-                    // Run import command.
-                    this.user.performCommand(this.topLabel + " " + CHALLENGES + " " + DEFAULT + " " + GENERATE +
-                            (this.overwriteMode ? " overwrite" : ""));
-                }
-                return true;
-            };
-            glow = this.overwriteMode;
-
-            break;
-        }
-        case EDIT_SETTINGS:
-        {
-            permissionSuffix = SETTINGS;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.settings");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.settings");
-            icon = new ItemStack(Material.CRAFTING_TABLE);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new EditSettingsGUI(this.addon,
-                        this.world,
-                        this.user,
-                        this.topLabel,
-                        this.permissionPrefix,
-                        this).build();
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        }
-        case COMPLETE_WIPE:
-        {
-            permissionSuffix = WIPE;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.complete-wipe");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.complete-wipe");
-            icon = new ItemStack(Material.TNT);
-            clickHandler = (panel, user, clickType, slot) -> {
-
-                if (clickType.isRightClick())
-                {
-                	this.wipeAll = false;
-					this.build();
-				}
-                else
-                {
-                    new ConfirmationGUI(this.user, value -> {
-                        if (value)
-                        {
-                            this.addon.getChallengesManager().wipeDatabase(false);
-                            this.user.sendMessage("challenges.messages.admin.complete-wipe");
-                        }
-
-                        this.build();
-                    });
-                }
-
-                return true;
-            };
-            glow = true;
-
-            break;
-        }
-        case CHALLENGE_WIPE:
-        {
-            permissionSuffix = WIPE;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.challenge-wipe");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.challenge-wipe");
-            icon = new ItemStack(Material.TNT);
-            clickHandler = (panel, user, clickType, slot) -> {
-
-                if (clickType.isRightClick())
-                {
-                	this.wipeAll = true;
-                    this.build();
-                }
-                else
-                {
-                    new ConfirmationGUI(this.user, value -> {
-                        if (value)
-                        {
-                            this.addon.getChallengesManager().wipeDatabase(false);
-                            this.user.sendMessage("challenges.messages.admin.challenge-wipe");
-                        }
-
-                        this.build();
-                    });
-                }
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        }
-        case USER_WIPE:
-        {
-            permissionSuffix = WIPE;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.players-wipe");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.players-wipe");
-            icon = new ItemStack(Material.TNT);
-            clickHandler = (panel, user, clickType, slot) -> {
-
-                new ConfirmationGUI(this.user, value -> {
-                    if (value)
-                    {
-                        this.addon.getChallengesManager().wipePlayers();
-                        this.user.sendMessage("challenges.messages.admin.players-wipe");
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        }
-        case LIBRARY:
-        {
-            permissionSuffix = DOWNLOAD;
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.library");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.library");
-
-            if (WebManager.isEnabled())
-            {
-                icon = new ItemStack(Material.COBWEB);
-            }
-            else
-            {
-                description += "|" + this.user.getTranslation("challenges.gui.descriptions.admin.download-disabled");
-                icon = new ItemStack(Material.STRUCTURE_VOID);
-            }
-
-            clickHandler = (panel, user, clickType, slot) -> {
-                if (WebManager.isEnabled())
-                {
-                    ListLibraryGUI.open(this);
-                }
-
-                return true;
-            };
-            glow = false;
-
-            break;
-        }
-        default:
-            // This should never happen.
-            return null;
-        }
-
-        // If user does not have permission to run command, then change icon and clickHandler.
-        final String actionPermission = this.permissionPrefix + ADMIN + "." + CHALLENGES + "." + permissionSuffix;
-
-        if (!this.user.hasPermission(actionPermission))
-        {
-            icon = new ItemStack(Material.BARRIER);
-            clickHandler = (panel, user, clickType, slot) -> {
-                this.user.sendMessage("general.errors.no-permission", "[permission]", actionPermission);
-                return true;
-            };
-        }
-
-        return new PanelItemBuilder().
-                icon(icon).
-                name(name).
-                description(GuiUtils.stringSplit(description, this.addon.getChallengesSettings().getLoreLineLength())).
-                glow(glow).
-                clickHandler(clickHandler).
-                build();
-    }
-    
-
-// ---------------------------------------------------------------------
-// Section: Conversation
-// ---------------------------------------------------------------------
-
-
-    /**
-     * This method will close opened gui and writes inputText in chat. After players answers on
-     * inputText in chat, message will trigger consumer and gui will reopen.
-     * @param consumer Consumer that accepts player output text.
-     * @param question Message that will be displayed in chat when player triggers conversion.
-     */
-    private void getNewUniqueID(Consumer<String> consumer,
-        Function<String, Boolean> stringValidation,
-        @NonNull String question)
-    {
-        final User user = this.user;
-
-        Conversation conversation =
-            new ConversationFactory(BentoBox.getInstance()).withFirstPrompt(
-                new ValidatingPrompt()
-                {
-
-                    /**
-                     * Gets the text to display to the user when
-                     * this prompt is first presented.
-                     *
-                     * @param context Context information about the
-                     * conversation.
-                     * @return The text to display.
-                     */
-                    @Override
-                    public String getPromptText(ConversationContext context)
-                    {
-                        // Close input GUI.
-                        user.closeInventory();
-
-                        // There are no editable message. Just return question.
-                        return question;
-                    }
-
-
-                    /**
-                     * Override this method to check the validity of
-                     * the player's input.
-                     *
-                     * @param context Context information about the
-                     * conversation.
-                     * @param input The player's raw console input.
-                     * @return True or false depending on the
-                     * validity of the input.
-                     */
-                    @Override
-                    protected boolean isInputValid(ConversationContext context, String input)
-                    {
-                        return stringValidation.apply(GuiUtils.sanitizeInput(input));
-                    }
-
-
-                    /**
-                     * Optionally override this method to
-                     * display an additional message if the
-                     * user enters an invalid input.
-                     *
-                     * @param context Context information
-                     * about the conversation.
-                     * @param invalidInput The invalid input
-                     * provided by the user.
-                     * @return A message explaining how to
-                     * correct the input.
-                     */
-                    @Override
-                    protected String getFailedValidationText(ConversationContext context,
-                        String invalidInput)
-                    {
-                        return user.getTranslation("challenges.errors.unique-id", "[id]", GuiUtils.sanitizeInput(invalidInput));
-                    }
-
-
-                    /**
-                     * Override this method to accept and processes
-                     * the validated input from the user. Using the
-                     * input, the next Prompt in the prompt graph
-                     * should be returned.
-                     *
-                     * @param context Context information about the
-                     * conversation.
-                     * @param input The validated input text from
-                     * the user.
-                     * @return The next Prompt in the prompt graph.
-                     */
-                    @Override
-                    protected Prompt acceptValidatedInput(ConversationContext context, String input)
-                    {
-                        // Add answer to consumer.
-                        consumer.accept(GuiUtils.sanitizeInput(input));
-                        // End conversation
-                        return Prompt.END_OF_CONVERSATION;
-                    }
-                }).
-                // On cancel conversation will be closed.
-                withEscapeSequence("cancel").
-                // Use null value in consumer to detect if user has abandoned conversation.
-                addConversationAbandonedListener(abandonedEvent ->
-                {
-                    if (!abandonedEvent.gracefulExit())
-                    {
-                        consumer.accept(null);
-                    }
-                }).
-                withLocalEcho(false).
-                withPrefix(context -> user.getTranslation("challenges.gui.questions.prefix")).
-                buildConversation(user.getPlayer());
-
-        conversation.begin();
-    }
-}

src/main/java/world/bentobox/challenges/panel/admin/AdminPanel.java

@@ -0,0 +1,549 @@
+package world.bentobox.challenges.panel.admin;
+
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Consumer;
+import java.util.function.Function;
+
+import org.bukkit.Material;
+import org.bukkit.World;
+import org.bukkit.inventory.ItemStack;
+
+import world.bentobox.bentobox.api.panels.PanelItem;
+import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
+import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
+import world.bentobox.bentobox.api.user.User;
+import world.bentobox.challenges.ChallengesAddon;
+import world.bentobox.challenges.panel.CommonPanel;
+import world.bentobox.challenges.panel.ConversationUtils;
+import world.bentobox.challenges.panel.util.ChallengeTypeSelector;
+import world.bentobox.challenges.utils.Constants;
+import world.bentobox.challenges.utils.GuiUtils;
+import world.bentobox.challenges.utils.Utils;
+import world.bentobox.challenges.web.WebManager;
+
+
+/**
+ * This class contains Main
+ */
+public class AdminPanel extends CommonPanel
+{
+    // ---------------------------------------------------------------------
+    // Section: Constructor
+    // ---------------------------------------------------------------------
+
+    /**
+     * @param addon Addon where panel operates.
+     * @param world World from which panel was created.
+     * @param user User who created panel.
+     * @param topLabel Command top label which creates panel (f.e. island or ai)
+     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
+     */
+    private AdminPanel(ChallengesAddon addon,
+        World world,
+        User user,
+        String topLabel,
+        String permissionPrefix)
+    {
+        super(addon, user, world, topLabel, permissionPrefix);
+    }
+
+
+    /**
+     * Open the Challenges Admin GUI.
+     *
+     * @param addon the addon
+     * @param world the world
+     * @param user the user
+     * @param topLabel the top label
+     * @param permissionPrefix the permission prefix
+     */
+    public static void open(ChallengesAddon addon,
+        World world,
+        User user,
+        String topLabel,
+        String permissionPrefix)
+    {
+        new AdminPanel(addon, world, user, topLabel, permissionPrefix).build();
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Methods
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected void build()
+    {
+        PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(
+            this.user.getTranslation(Constants.TITLE + "admin-gui"));
+
+        GuiUtils.fillBorder(panelBuilder);
+
+        panelBuilder.item(10, this.createButton(Button.COMPLETE_USER_CHALLENGES));
+        panelBuilder.item(19, this.createButton(Button.RESET_USER_CHALLENGES));
+
+        // Add All Player Data removal.
+        panelBuilder.item(28, this.createButton(Button.USER_WIPE));
+
+        // Add Challenges
+        panelBuilder.item(12, this.createButton(Button.ADD_CHALLENGE));
+        panelBuilder.item(13, this.createButton(Button.ADD_LEVEL));
+
+        // Edit Challenges
+        panelBuilder.item(21, this.createButton(Button.EDIT_CHALLENGE));
+        panelBuilder.item(22, this.createButton(Button.EDIT_LEVEL));
+
+        // Remove Challenges
+        panelBuilder.item(30, this.createButton(Button.DELETE_CHALLENGE));
+        panelBuilder.item(31, this.createButton(Button.DELETE_LEVEL));
+
+        // Import Challenges
+        panelBuilder.item(15, this.createButton(Button.IMPORT_CHALLENGES));
+        panelBuilder.item(24, this.createButton(Button.LIBRARY));
+
+        // Not added as I do not think admins should use it. It still will be able via command.
+        //		panelBuilder.item(33, this.createButton(Button.DEFAULT_EXPORT_CHALLENGES));
+
+        // Edit Addon Settings
+        panelBuilder.item(16, this.createButton(Button.EDIT_SETTINGS));
+
+        // Button that deletes everything from challenges addon
+
+		if (this.wipeAll)
+		{
+			panelBuilder.item(34, this.createButton(Button.COMPLETE_WIPE));
+		}
+		else
+		{
+			panelBuilder.item(34, this.createButton(Button.CHALLENGE_WIPE));
+		}
+
+        panelBuilder.item(44, this.returnButton);
+
+        panelBuilder.build();
+    }
+
+
+    /**
+     * This method is used to create PanelItem for each button type.
+     * @param button Button which must be created.
+     * @return PanelItem with necessary functionality.
+     */
+    private PanelItem createButton(Button button)
+    {
+        final String name = this.user.getTranslation(Constants.BUTTON + button.name().toLowerCase() + ".name");
+        List<String> description = new ArrayList<>(3);
+        description.add(this.user.getTranslation(Constants.BUTTON + button.name().toLowerCase() + ".description"));
+
+        ItemStack icon;
+        boolean glow;
+        PanelItem.ClickHandler clickHandler;
+
+
+        switch (button)
+        {
+            case COMPLETE_USER_CHALLENGES -> {
+                icon = new ItemStack(Material.WRITTEN_BOOK);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    ListUsersPanel.open(this, ListUsersPanel.Mode.COMPLETE);
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-open"));
+            }
+            case RESET_USER_CHALLENGES -> {
+                icon = new ItemStack(Material.WRITABLE_BOOK);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    if (clickType.isRightClick())
+                    {
+                        this.resetAllMode = !this.resetAllMode;
+                        this.build();
+                    }
+                    else
+                    {
+                        ListUsersPanel.open(this,
+                            this.resetAllMode ? ListUsersPanel.Mode.RESET_ALL : ListUsersPanel.Mode.RESET);
+                    }
+
+                    return true;
+                };
+                glow = this.resetAllMode;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "left-click-to-open"));
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "right-click-to-reset-all"));
+            }
+            case ADD_CHALLENGE -> {
+                icon = new ItemStack(Material.BOOK);
+                clickHandler = (panel, user, clickType, slot) -> {
+
+                    String gameModePrefix = Utils.getGameMode(this.world).toLowerCase() + "_";
+
+                    // This consumer process new bundle creating with a name and id from given
+                    // consumer value..
+                    Consumer<String> challengeIdConsumer = value -> {
+                        if (value != null)
+                        {
+                            ChallengeTypeSelector.open(this.user,
+                                (type, requirements) -> EditChallengePanel.open(this,
+                                    this.addon.getChallengesManager().createChallenge(
+                                        gameModePrefix + Utils.sanitizeInput(value),
+                                        value,
+                                        type,
+                                        requirements)));
+                        }
+                        else
+                        {
+                            // Operation is canceled. Open this panel again.
+                            this.build();
+                        }
+                    };
+
+                    // This function checks if generator with a given ID already exist.
+                    Function<String, Boolean> validationFunction = uniqueId ->
+                        !this.addon.getChallengesManager().containsChallenge(gameModePrefix + Utils.sanitizeInput(uniqueId));
+
+                    // Call a conversation API to get input string.
+                    ConversationUtils.createIDStringInput(challengeIdConsumer,
+                        validationFunction,
+                        this.user,
+                        this.user.getTranslation(Constants.CONVERSATIONS + "write-name"),
+                        this.user.getTranslation(Constants.CONVERSATIONS + "new-object-created",
+                            Constants.WORLD, this.world.getName()),
+                        Constants.CONVERSATIONS + "object-already-exists");
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-create"));
+            }
+            case ADD_LEVEL -> {
+                icon = new ItemStack(Material.BOOK);
+                clickHandler = (panel, user, clickType, slot) -> {
+
+                    String gameModePrefix = Utils.getGameMode(this.world).toLowerCase() + "_";
+
+                    // This consumer process new bundle creating with a name and id from given
+                    // consumer value..
+                    Consumer<String> levelIdConsumer = value -> {
+                        if (value != null)
+                        {
+                            EditLevelPanel.open(this,
+                                this.addon.getChallengesManager().createLevel(
+                                    gameModePrefix + Utils.sanitizeInput(value),
+                                    value,
+                                    world));
+                        }
+                        else
+                        {
+                            // Operation is canceled. Open this panel again.
+                            this.build();
+                        }
+                    };
+
+                    // This function checks if generator with a given ID already exist.
+                    Function<String, Boolean> validationFunction = uniqueId ->
+                        !this.addon.getChallengesManager().containsLevel(gameModePrefix + Utils.sanitizeInput(uniqueId));
+
+                    // Call a conversation API to get input string.
+                    ConversationUtils.createIDStringInput(levelIdConsumer,
+                        validationFunction,
+                        this.user,
+                        this.user.getTranslation(Constants.CONVERSATIONS + "write-name"),
+                        this.user.getTranslation(Constants.CONVERSATIONS + "new-object-created",
+                            Constants.GAMEMODE, Utils.getGameMode(this.world)),
+                        Constants.CONVERSATIONS + "object-already-exists");
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-create"));
+            }
+            case EDIT_CHALLENGE -> {
+                icon = new ItemStack(Material.ANVIL);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    ListChallengesPanel.open(this, ListChallengesPanel.Mode.EDIT);
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-open"));
+            }
+            case EDIT_LEVEL -> {
+                icon = new ItemStack(Material.ANVIL);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    ListLevelsPanel.open(this, ListLevelsPanel.Mode.EDIT);
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-open"));
+            }
+            case DELETE_CHALLENGE -> {
+                icon = new ItemStack(Material.LAVA_BUCKET);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    ListChallengesPanel.open(this, ListChallengesPanel.Mode.DELETE);
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-open"));
+            }
+            case DELETE_LEVEL -> {
+                icon = new ItemStack(Material.LAVA_BUCKET);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    ListLevelsPanel.open(this, ListLevelsPanel.Mode.DELETE);
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-open"));
+            }
+            case EDIT_SETTINGS -> {
+                icon = new ItemStack(Material.CRAFTING_TABLE);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    EditSettingsPanel.open(this);
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-open"));
+            }
+            case IMPORT_CHALLENGES -> {
+                icon = new ItemStack(Material.HOPPER);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    // TODO: Importing GUI.
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-open"));
+            }
+            case EXPORT_CHALLENGES -> {
+                icon = new ItemStack(Material.HOPPER);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    // TODO: Exporting GUI.
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-export"));
+            }
+            case LIBRARY -> {
+                if (WebManager.isEnabled())
+                {
+                    icon = new ItemStack(Material.COBWEB);
+                }
+                else
+                {
+                    icon = new ItemStack(Material.STRUCTURE_VOID);
+                }
+
+                clickHandler = (panel, user, clickType, slot) -> {
+                    if (WebManager.isEnabled())
+                    {
+                        ListLibraryPanel.open(this);
+                    }
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-open"));
+            }
+            case COMPLETE_WIPE -> {
+                icon = new ItemStack(Material.TNT);
+                clickHandler = (panel, user, clickType, slot) -> {
+
+                    if (clickType.isRightClick())
+                    {
+                        this.wipeAll = false;
+                        this.build();
+                    }
+                    else
+                    {
+                        Consumer<Boolean> consumer = value -> {
+                            if (value)
+                            {
+                                this.addon.getChallengesManager().wipeDatabase(this.wipeAll);
+                            }
+
+                            this.build();
+                        };
+
+                        // Create conversation that gets user acceptance to delete generator data.
+                        ConversationUtils.createConfirmation(
+                            consumer,
+                            this.user,
+                            this.user.getTranslation(Constants.CONVERSATIONS + "confirm-all-data-deletion",
+                                Constants.GAMEMODE, Utils.getGameMode(this.world)),
+                            this.user.getTranslation(Constants.CONVERSATIONS + "all-data-removed",
+                                Constants.GAMEMODE, Utils.getGameMode(this.world)));
+                    }
+
+                    return true;
+                };
+                glow = true;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "left-click-to-wipe"));
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "right-click-to-switch"));
+            }
+            case CHALLENGE_WIPE -> {
+                icon = new ItemStack(Material.TNT);
+                clickHandler = (panel, user, clickType, slot) -> {
+
+                    if (clickType.isRightClick())
+                    {
+                        this.wipeAll = true;
+                        this.build();
+                    }
+                    else
+                    {
+                        Consumer<Boolean> consumer = value -> {
+                            if (value)
+                            {
+                                this.addon.getChallengesManager().wipeDatabase(this.wipeAll);
+                            }
+
+                            this.build();
+                        };
+
+                        // Create conversation that gets user acceptance to delete generator data.
+                        ConversationUtils.createConfirmation(
+                            consumer,
+                            this.user,
+                            this.user.getTranslation(Constants.CONVERSATIONS + "confirm-challenge-data-deletion",
+                                Constants.GAMEMODE, Utils.getGameMode(this.world)),
+                            this.user.getTranslation(Constants.CONVERSATIONS + "challenge-data-removed",
+                                Constants.GAMEMODE, Utils.getGameMode(this.world)));
+                    }
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "left-click-to-wipe"));
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "right-click-to-switch"));
+            }
+            case USER_WIPE -> {
+                icon = new ItemStack(Material.TNT);
+                clickHandler = (panel, user, clickType, slot) -> {
+
+                    Consumer<Boolean> consumer = value -> {
+                        if (value)
+                        {
+                            this.addon.getChallengesManager().wipePlayers();
+                        }
+
+                        this.build();
+                    };
+
+                    // Create conversation that gets user acceptance to delete generator data.
+                    ConversationUtils.createConfirmation(
+                        consumer,
+                        this.user,
+                        this.user.getTranslation(Constants.CONVERSATIONS + "confirm-user-data-deletion",
+                            Constants.GAMEMODE, Utils.getGameMode(this.world)),
+                        this.user.getTranslation(Constants.CONVERSATIONS + "user-data-removed",
+                            Constants.GAMEMODE, Utils.getGameMode(this.world)));
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslationOrNothing(Constants.TIPS + "click-to-wipe"));
+            }
+            default -> {
+                icon = new ItemStack(Material.PAPER);
+                clickHandler = null;
+                glow = false;
+            }
+        }
+
+        return new PanelItemBuilder().
+            icon(icon).
+            name(name).
+            description(description).
+            glow(glow).
+            clickHandler(clickHandler).
+            build();
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Enums
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * This enum contains all button variations. Just for cleaner code.
+     */
+    private enum Button
+    {
+        COMPLETE_USER_CHALLENGES,
+        RESET_USER_CHALLENGES,
+        ADD_CHALLENGE,
+        ADD_LEVEL,
+        EDIT_CHALLENGE,
+        EDIT_LEVEL,
+        DELETE_CHALLENGE,
+        DELETE_LEVEL,
+        EDIT_SETTINGS,
+        IMPORT_CHALLENGES,
+        EXPORT_CHALLENGES,
+        /**
+         * Allows to remove whole database
+         */
+        COMPLETE_WIPE,
+        /**
+         * Allows to remove only challenges and levels
+         */
+        CHALLENGE_WIPE,
+        /**
+         * Allows to remove only players data
+         */
+        USER_WIPE,
+        /**
+         * Allows to access Web Library
+         */
+        LIBRARY
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Variables
+    // ---------------------------------------------------------------------
+
+    /**
+     * This indicate if Reset Challenges must work as reset all.
+     */
+    private boolean resetAllMode;
+
+    /**
+     * This indicate if wipe button should clear all data, or only challenges.
+     */
+    private boolean wipeAll;
+}

src/main/java/world/bentobox/challenges/panel/admin/EditLevelGUI.java

@@ -1,764 +0,0 @@
-package world.bentobox.challenges.panel.admin;
-
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.stream.Collectors;
-
-import org.bukkit.ChatColor;
-import org.bukkit.Material;
-import org.bukkit.World;
-import org.bukkit.inventory.ItemStack;
-
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.ChallengesAddon;
-import world.bentobox.challenges.managers.ChallengesManager;
-import world.bentobox.challenges.database.object.Challenge;
-import world.bentobox.challenges.database.object.ChallengeLevel;
-import world.bentobox.challenges.panel.CommonGUI;
-import world.bentobox.challenges.panel.util.ItemSwitchGUI;
-import world.bentobox.challenges.panel.util.NumberGUI;
-import world.bentobox.challenges.panel.util.SelectBlocksGUI;
-import world.bentobox.challenges.panel.util.SelectChallengeGUI;
-import world.bentobox.challenges.panel.util.StringListGUI;
-import world.bentobox.challenges.utils.GuiUtils;
-import world.bentobox.challenges.utils.Utils;
-
-
-/**
- * This class contains all necessary elements to create Levels Edit GUI.
- */
-public class EditLevelGUI extends CommonGUI
-{
-    // ---------------------------------------------------------------------
-    // Section: Constructors
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * @param addon Addon where panel operates.
-     * @param world World from which panel was created.
-     * @param user User who created panel.
-     * @param topLabel Command top label which creates panel (f.e. island or ai)
-     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
-     * @param challengeLevel ChallengeLevel that must be edited.
-     */
-    public EditLevelGUI(ChallengesAddon addon,
-            World world,
-            User user,
-            ChallengeLevel challengeLevel,
-            String topLabel,
-            String permissionPrefix)
-    {
-        this(addon, world, user, challengeLevel, topLabel, permissionPrefix, null);
-    }
-
-
-    /**
-     * @param addon Addon where panel operates.
-     * @param world World from which panel was created.
-     * @param user User who created panel.
-     * @param topLabel Command top label which creates panel (f.e. island or ai)
-     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
-     * @param challengeLevel ChallengeLevel that must be edited.
-     */
-    public EditLevelGUI(ChallengesAddon addon,
-            World world,
-            User user,
-            ChallengeLevel challengeLevel,
-            String topLabel,
-            String permissionPrefix,
-            CommonGUI parentGUI)
-    {
-        super(addon, world, user, topLabel, permissionPrefix, parentGUI);
-        this.challengeLevel = challengeLevel;
-        this.currentMenuType = MenuType.PROPERTIES;
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Methods
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * This method builds all necessary elements in GUI panel.
-     */
-    @Override
-    public void build()
-    {
-        PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(
-                this.user.getTranslation("challenges.gui.title.admin.edit-level-title"));
-
-        GuiUtils.fillBorder(panelBuilder);
-
-        panelBuilder.item(2, this.createMenuButton(MenuType.PROPERTIES));
-        panelBuilder.item(4, this.createMenuButton(MenuType.REWARDS));
-        panelBuilder.item(6, this.createMenuButton(MenuType.CHALLENGES));
-
-        if (this.currentMenuType.equals(MenuType.PROPERTIES))
-        {
-            this.buildMainPropertiesPanel(panelBuilder);
-        }
-        else if (this.currentMenuType.equals(MenuType.CHALLENGES))
-        {
-            this.buildChallengesPanel(panelBuilder);
-        }
-        else if (this.currentMenuType.equals(MenuType.REWARDS))
-        {
-            this.buildRewardsPanel(panelBuilder);
-        }
-
-        panelBuilder.item(44, this.returnButton);
-
-        // Save challenge level every time this gui is build.
-        // It will ensure that changes are stored in database.
-        this.addon.getChallengesManager().saveLevel(this.challengeLevel);
-
-        panelBuilder.build();
-    }
-
-
-    /**
-     * This class populate LevelsEditGUI with main level settings.
-     * @param panelBuilder PanelBuilder where icons must be added.
-     */
-    private void buildMainPropertiesPanel(PanelBuilder panelBuilder)
-    {
-        panelBuilder.item(10, this.createButton(Button.NAME));
-
-        panelBuilder.item(19, this.createButton(Button.ICON));
-        panelBuilder.item(28, this.createButton(Button.CLOSED_ICON));
-        panelBuilder.item(22, this.createButton(Button.UNLOCK_MESSAGE));
-        panelBuilder.item(25, this.createButton(Button.ORDER));
-
-        panelBuilder.item(31, this.createButton(Button.WAIVER_AMOUNT));
-    }
-
-
-    /**
-     * This class populate LevelsEditGUI with level rewards.
-     * @param panelBuilder PanelBuilder where icons must be added.
-     */
-    private void buildRewardsPanel(PanelBuilder panelBuilder)
-    {
-        panelBuilder.item(12, this.createButton(Button.REWARD_DESCRIPTION));
-        panelBuilder.item(21, this.createButton(Button.REWARD_COMMANDS));
-
-        panelBuilder.item(13, this.createButton(Button.REWARD_ITEM));
-        panelBuilder.item(22, this.createButton(Button.REWARD_EXPERIENCE));
-        panelBuilder.item(31, this.createButton(Button.REWARD_MONEY));
-    }
-
-
-    /**
-     * This class populate LevelsEditGUI with level challenges.
-     * @param panelBuilder PanelBuilder where icons must be added.
-     */
-    private void buildChallengesPanel(PanelBuilder panelBuilder)
-    {
-        List<Challenge> challengeList = this.addon.getChallengesManager().getLevelChallenges(this.challengeLevel);
-
-        final int MAX_ELEMENTS = 21;
-
-        if (this.pageIndex < 0)
-        {
-            this.pageIndex = challengeList.size() / MAX_ELEMENTS;
-        }
-        else if (this.pageIndex > (challengeList.size() / MAX_ELEMENTS))
-        {
-            this.pageIndex = 0;
-        }
-
-        int challengeIndex = MAX_ELEMENTS * this.pageIndex;
-
-        // I want first row to be only for navigation and return button.
-        int index = 10;
-
-        while (challengeIndex < ((this.pageIndex + 1) * MAX_ELEMENTS) &&
-                challengeIndex < challengeList.size() &&
-                index < 36)
-        {
-            if (!panelBuilder.slotOccupied(index))
-            {
-                panelBuilder.item(index, this.createChallengeIcon(challengeList.get(challengeIndex++)));
-            }
-
-            index++;
-        }
-
-        // Navigation buttons only if necessary
-        if (challengeList.size() > MAX_ELEMENTS)
-        {
-            panelBuilder.item(18, this.getButton(CommonButtons.PREVIOUS));
-            panelBuilder.item(26, this.getButton(CommonButtons.NEXT));
-        }
-
-        panelBuilder.item(39, this.createButton(Button.ADD_CHALLENGE));
-        panelBuilder.item(41, this.createButton(Button.REMOVE_CHALLENGE));
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Other methods
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * This method creates top menu buttons, that allows to switch "tabs".
-     * @param menuType Menu Type which button must be constructed.
-     * @return PanelItem that represents given menu type.
-     */
-    private PanelItem createMenuButton(MenuType menuType)
-    {
-        ItemStack icon;
-        String name;
-        String description;
-        boolean glow;
-        PanelItem.ClickHandler clickHandler;
-
-        switch (menuType)
-        {
-        case PROPERTIES:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.properties");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.properties");
-            icon = new ItemStack(Material.CRAFTING_TABLE);
-            clickHandler = (panel, user, clickType, slot) -> {
-                this.currentMenuType = MenuType.PROPERTIES;
-                this.build();
-
-                return true;
-            };
-            glow = this.currentMenuType.equals(MenuType.PROPERTIES);
-            break;
-        }
-        case CHALLENGES:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.challenges");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.challenges");
-            icon = new ItemStack(Material.RAIL);
-            clickHandler = (panel, user, clickType, slot) -> {
-                this.currentMenuType = MenuType.CHALLENGES;
-                this.build();
-
-                return true;
-            };
-            glow = this.currentMenuType.equals(MenuType.CHALLENGES);
-            break;
-        }
-        case REWARDS:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.rewards");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.rewards");
-            icon = new ItemStack(Material.DROPPER);
-            clickHandler = (panel, user, clickType, slot) -> {
-                this.currentMenuType = MenuType.REWARDS;
-                this.build();
-
-                return true;
-            };
-            glow = this.currentMenuType.equals(MenuType.REWARDS);
-            break;
-        }
-        default:
-            return null;
-        }
-
-        return new PanelItemBuilder().
-                icon(icon).
-                name(name).
-                description(GuiUtils.stringSplit(description, this.addon.getChallengesSettings().getLoreLineLength())).
-                glow(glow).
-                clickHandler(clickHandler).
-                build();
-    }
-
-
-    /**
-     * This method creates given challenge icon. On click it should open Edit Challenge GUI.
-     * @param challenge Challenge which icon must be created.
-     * @return PanelItem that represents given challenge.
-     */
-    private PanelItem createChallengeIcon(Challenge challenge)
-    {
-        return new PanelItemBuilder().
-                name(ChatColor.translateAlternateColorCodes('&', challenge.getFriendlyName())).
-                description(GuiUtils.stringSplit(
-                        challenge.getDescription(),
-                        this.addon.getChallengesSettings().getLoreLineLength())).
-                icon(challenge.getIcon()).
-                clickHandler((panel, user1, clickType, slot) -> {
-                    // Open challenges edit screen.
-                    new EditChallengeGUI(this.addon,
-                            this.world,
-                            this.user,
-                            challenge,
-                            this.topLabel,
-                            this.permissionPrefix,
-                            this).build();
-                    return true;
-                }).
-                glow(!challenge.isDeployed()).
-                build();
-
-    }
-
-
-    /**
-     * This method creates buttons for default main menu.
-     * @param button Button which panel item must be created.
-     * @return PanelItem that represents given button.
-     */
-    private PanelItem createButton(Button button)
-    {
-        ItemStack icon;
-        String name;
-        List<String> description;
-        boolean glow;
-        PanelItem.ClickHandler clickHandler;
-
-        final int lineLength = this.addon.getChallengesSettings().getLoreLineLength();
-
-        switch (button)
-        {
-        case NAME:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.name");
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.name-level"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]", this.challengeLevel.getFriendlyName()));
-            icon = new ItemStack(Material.DROPPER);
-            clickHandler = (panel, user, clickType, slot) -> {
-
-                this.getFriendlyName(reply ->
-                    {
-                        if (reply != null)
-                        {
-                            this.challengeLevel.setFriendlyName(reply);
-                        }
-                        this.build();
-                    },
-                    this.user.getTranslation("challenges.gui.questions.admin.level-name"),
-                    this.challengeLevel.getFriendlyName()
-                );
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case ICON:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.icon");
-            description = Collections.singletonList(this.user.getTranslation(
-                    "challenges.gui.descriptions.admin.icon-level"));
-            icon = this.challengeLevel.getIcon();
-            clickHandler = (panel, user, clickType, slot) -> {
-
-                new SelectBlocksGUI(this.user, true, (status, materials) -> {
-                    if (status)
-                    {
-                        materials.forEach(material ->
-                            this.challengeLevel.setIcon(new ItemStack(material)));
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case CLOSED_ICON:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.locked-icon");
-            description = Collections.singletonList(this.user.getTranslation(
-                    "challenges.gui.descriptions.admin.locked-icon"));
-
-            boolean isNull = this.challengeLevel.getLockedIcon() == null;
-
-            if (isNull)
-            {
-                icon = new ItemStack(Material.BARRIER);
-            }
-            else
-            {
-                icon = this.challengeLevel.getLockedIcon().clone();
-            }
-
-            clickHandler = (panel, user, clickType, slot) -> {
-                new SelectBlocksGUI(this.user, true, (status, materials) -> {
-                    if (status)
-                    {
-                        materials.forEach(material ->
-                            this.challengeLevel.setLockedIcon(new ItemStack(material)));
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case UNLOCK_MESSAGE:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.description");
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.description"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]", "|" + this.challengeLevel.getUnlockMessage()));
-            icon = new ItemStack(Material.WRITABLE_BOOK);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new StringListGUI(this.user, this.challengeLevel.getUnlockMessage(), lineLength, (status, value) -> {
-                    if (status)
-                    {
-                    	String singleLineMessage = value.stream().
-							map(s -> s + "|").
-							collect(Collectors.joining());
-
-                    	if (singleLineMessage.endsWith("|"))
-						{
-							singleLineMessage = singleLineMessage.substring(0, singleLineMessage.length() - 1);
-						}
-
-						this.challengeLevel.setUnlockMessage(singleLineMessage);
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case ORDER:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.order");
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.order"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]", Integer.toString(this.challengeLevel.getOrder())));
-            icon = new ItemStack(Material.DROPPER);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new NumberGUI(this.user, this.challengeLevel.getOrder(), -1, 54, lineLength, (status, value) -> {
-                    if (status)
-                    {
-                        this.challengeLevel.setOrder(value);
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case WAIVER_AMOUNT:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.waiver-amount");
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.waiver-amount"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]", Integer.toString(this.challengeLevel.getWaiverAmount())));
-
-            icon = new ItemStack(Material.REDSTONE_TORCH);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new NumberGUI(this.user, this.challengeLevel.getWaiverAmount(), 0, lineLength, (status, value) -> {
-                    if (status)
-                    {
-                        this.challengeLevel.setWaiverAmount(value);
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-
-        case REWARD_DESCRIPTION:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.reward-text");
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.reward-text-level"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]", "|" + this.challengeLevel.getRewardText()));
-            icon = new ItemStack(Material.WRITTEN_BOOK);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new StringListGUI(this.user, this.challengeLevel.getRewardText(), lineLength, (status, value) -> {
-                    if (status)
-                    {
-						String singleLineMessage = value.stream().
-							map(s -> s + "|").
-							collect(Collectors.joining());
-
-						if (singleLineMessage.endsWith("|"))
-						{
-							singleLineMessage = singleLineMessage.substring(0, singleLineMessage.length() - 1);
-						}
-
-						this.challengeLevel.setRewardText(singleLineMessage);
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case REWARD_ITEM:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.reward-items");
-
-            description = new ArrayList<>(this.challengeLevel.getRewardItems().size() + 1);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.reward-items"));
-
-            Utils.groupEqualItems(this.challengeLevel.getRewardItems()).forEach(itemStack ->
-            description.addAll(this.generateItemStackDescription(itemStack)));
-
-            icon = new ItemStack(Material.CHEST);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new ItemSwitchGUI(this.user, this.challengeLevel.getRewardItems(), lineLength, (status, value) -> {
-                    if (status)
-                    {
-                        this.challengeLevel.setRewardItems(value);
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case REWARD_EXPERIENCE:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.reward-experience");
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.reward-experience"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]", Integer.toString(this.challengeLevel.getRewardExperience())));
-            icon = new ItemStack(Material.EXPERIENCE_BOTTLE);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new NumberGUI(this.user, this.challengeLevel.getRewardExperience(), 0, lineLength, (status, value) -> {
-                    if (status)
-                    {
-                        this.challengeLevel.setRewardExperience(value);
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case REWARD_MONEY:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.reward-money");
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.reward-money"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]", Integer.toString(this.challengeLevel.getRewardMoney())));
-
-            icon = new ItemStack(this.addon.isEconomyProvided() ? Material.GOLD_INGOT : Material.BARRIER);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new NumberGUI(this.user, this.challengeLevel.getRewardMoney(), 0, lineLength, (status, value) -> {
-                    if (status)
-                    {
-                        this.challengeLevel.setRewardMoney(value);
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-
-            glow = false;
-            break;
-        }
-        case REWARD_COMMANDS:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.reward-commands");
-            description = new ArrayList<>(this.challengeLevel.getRewardCommands().size() + 1);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.reward-commands"));
-
-            for (String command : this.challengeLevel.getRewardCommands())
-            {
-                description.add(this.user.getTranslation("challenges.gui.descriptions.command",
-                        "[command]", command));
-            }
-
-            icon = new ItemStack(Material.COMMAND_BLOCK);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new StringListGUI(this.user, this.challengeLevel.getRewardCommands(), lineLength, (status, value) -> {
-                    if (status)
-                    {
-                        this.challengeLevel.setRewardCommands(value);
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-
-        case ADD_CHALLENGE:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.add-challenge");
-            description = Collections.singletonList(this.user.getTranslation("challenges.gui.descriptions.admin.add-challenge"));
-            icon = new ItemStack(Material.WATER_BUCKET);
-            clickHandler = (panel, user, clickType, slot) -> {
-                ChallengesManager manager = this.addon.getChallengesManager();
-
-                // Get all challenge that is not in current level.
-                List<Challenge> challengeList = manager.getAllChallenges(this.world);
-                challengeList.removeAll(manager.getLevelChallenges(this.challengeLevel));
-
-                // Generate descriptions for these challenges
-                Map<Challenge, List<String>> challengeDescriptionMap = challengeList.stream().
-                        collect(Collectors.toMap(challenge -> challenge,
-                                challenge -> this.generateChallengeDescription(challenge, this.user.getPlayer()),
-                                (a, b) -> b,
-                                () -> new LinkedHashMap<>(challengeList.size())));
-
-                // Open select gui
-                new SelectChallengeGUI(this.user, challengeDescriptionMap, lineLength, (status, valueSet) -> {
-                    if (status)
-                    {
-                        valueSet.forEach(challenge -> manager.addChallengeToLevel(challenge, this.challengeLevel));
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case REMOVE_CHALLENGE:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.remove-challenge");
-            description = Collections.singletonList(this.user.getTranslation("challenges.gui.descriptions.admin.remove-challenge"));
-            icon = new ItemStack(Material.LAVA_BUCKET);
-            clickHandler = (panel, user, clickType, slot) -> {
-                ChallengesManager manager = this.addon.getChallengesManager();
-
-                // Get all challenge that is in current level.
-                List<Challenge> challengeList = manager.getLevelChallenges(this.challengeLevel);
-
-                // Generate descriptions for these challenges
-                Map<Challenge, List<String>> challengeDescriptionMap = challengeList.stream().
-                        collect(Collectors.toMap(challenge -> challenge,
-                                challenge -> this.generateChallengeDescription(challenge, this.user.getPlayer()),
-                                (a, b) -> b,
-                                () -> new LinkedHashMap<>(challengeList.size())));
-
-                // Open select gui
-                new SelectChallengeGUI(this.user, challengeDescriptionMap, lineLength, (status, valueSet) -> {
-                    if (status)
-                    {
-                        valueSet.forEach(challenge -> manager.removeChallengeFromLevel(challenge, this.challengeLevel));
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        default:
-            return null;
-        }
-
-
-
-        return new PanelItemBuilder().
-                icon(icon).
-                name(name).
-                description(GuiUtils.stringSplit(description, lineLength)).
-                glow(glow).
-                clickHandler(clickHandler).
-                build();
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Enums
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * Represents different buttons that could be in menus.
-     */
-    private enum Button
-    {
-        NAME,
-        ICON,
-        CLOSED_ICON,
-        UNLOCK_MESSAGE,
-        ORDER,
-        WAIVER_AMOUNT,
-
-        REWARD_DESCRIPTION,
-        REWARD_ITEM,
-        REWARD_EXPERIENCE,
-        REWARD_MONEY,
-        REWARD_COMMANDS,
-
-        ADD_CHALLENGE,
-        REMOVE_CHALLENGE
-    }
-
-
-    /**
-     * Represents different types of menus
-     */
-    private enum MenuType
-    {
-        PROPERTIES,
-        CHALLENGES,
-        REWARDS
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Variables
-    // ---------------------------------------------------------------------
-
-    /**
-     * This variable holds current challenge level that is in editing GUI.
-     */
-    private ChallengeLevel challengeLevel;
-
-    /**
-     * Variable holds current active menu.
-     */
-    private MenuType currentMenuType;
-}

src/main/java/world/bentobox/challenges/panel/admin/EditLevelPanel.java

@@ -0,0 +1,876 @@
+package world.bentobox.challenges.panel.admin;
+
+
+import java.util.*;
+import java.util.function.Consumer;
+import java.util.stream.Collectors;
+
+import org.bukkit.Material;
+import org.bukkit.World;
+import org.bukkit.event.inventory.InventoryClickEvent;
+import org.bukkit.event.inventory.InventoryCloseEvent;
+import org.bukkit.inventory.ItemStack;
+
+import world.bentobox.bentobox.api.panels.PanelItem;
+import world.bentobox.bentobox.api.panels.PanelListener;
+import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
+import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
+import world.bentobox.bentobox.api.user.User;
+import world.bentobox.bentobox.util.Util;
+import world.bentobox.challenges.ChallengesAddon;
+import world.bentobox.challenges.managers.ChallengesManager;
+import world.bentobox.challenges.database.object.Challenge;
+import world.bentobox.challenges.database.object.ChallengeLevel;
+import world.bentobox.challenges.panel.CommonPagedPanel;
+import world.bentobox.challenges.panel.CommonPanel;
+import world.bentobox.challenges.panel.ConversationUtils;
+import world.bentobox.challenges.panel.util.ItemSelector;
+import world.bentobox.challenges.panel.util.ChallengeSelector;
+import world.bentobox.challenges.utils.Constants;
+import world.bentobox.challenges.utils.GuiUtils;
+import world.bentobox.challenges.utils.Utils;
+
+
+/**
+ * This class contains all necessary elements to create Levels Edit GUI.
+ */
+public class EditLevelPanel extends CommonPagedPanel
+{
+    // ---------------------------------------------------------------------
+    // Section: Constructors
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * @param addon Addon where panel operates.
+     * @param world World from which panel was created.
+     * @param user User who created panel.
+     * @param topLabel Command top label which creates panel (f.e. island or ai)
+     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
+     * @param challengeLevel ChallengeLevel that must be edited.
+     */
+    private EditLevelPanel(ChallengesAddon addon,
+        User user,
+        World world,
+        String topLabel,
+        String permissionPrefix,
+        ChallengeLevel challengeLevel)
+    {
+        super(addon, user, world, topLabel, permissionPrefix);
+        this.challengeLevel = challengeLevel;
+        this.currentMenuType = MenuType.PROPERTIES;
+    }
+
+
+    /**
+     * @param challengeLevel ChallengeLevel that must be edited.
+     */
+    private EditLevelPanel(CommonPanel parentGUI, ChallengeLevel challengeLevel)
+    {
+        super(parentGUI);
+        this.challengeLevel = challengeLevel;
+        this.currentMenuType = MenuType.PROPERTIES;
+    }
+
+
+    /**
+     * Open the Challenges Level Edit GUI.
+     *
+     * @param addon the addon
+     * @param world the world
+     * @param user the user
+     * @param topLabel the top label
+     * @param permissionPrefix the permission prefix
+     * @param level - level that needs editing
+     */
+    public static void open(ChallengesAddon addon,
+        User user,
+        World world,
+        String topLabel,
+        String permissionPrefix,
+        ChallengeLevel level)
+    {
+        new EditLevelPanel(addon, user, world, topLabel, permissionPrefix, level).build();
+    }
+
+
+    /**
+     * Open the Challenges Level Edit GUI.
+     *
+     * @param panel - Parent Panel
+     * @param level - level that needs editing
+     */
+    public static void open(CommonPanel panel,  ChallengeLevel level)
+    {
+        new EditLevelPanel(panel, level).build();
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Methods
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * This method builds all necessary elements in GUI panel.
+     */
+    @Override
+    protected void build()
+    {
+        PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(
+            this.user.getTranslation(Constants.TITLE + "edit-level",
+                "[level]", this.challengeLevel.getFriendlyName()));
+
+        GuiUtils.fillBorder(panelBuilder);
+
+        panelBuilder.item(2, this.createMenuButton(MenuType.PROPERTIES));
+        panelBuilder.item(4, this.createMenuButton(MenuType.REWARDS));
+        panelBuilder.item(6, this.createMenuButton(MenuType.CHALLENGES));
+
+        if (this.currentMenuType.equals(MenuType.PROPERTIES))
+        {
+            this.buildMainPropertiesPanel(panelBuilder);
+        }
+        else if (this.currentMenuType.equals(MenuType.CHALLENGES))
+        {
+            this.buildChallengesPanel(panelBuilder);
+        }
+        else if (this.currentMenuType.equals(MenuType.REWARDS))
+        {
+            this.buildRewardsPanel(panelBuilder);
+        }
+
+        panelBuilder.item(44, this.returnButton);
+
+        // Save challenge level every time this gui is build.
+        // It will ensure that changes are stored in database.
+        this.addon.getChallengesManager().saveLevel(this.challengeLevel);
+
+        panelBuilder.build();
+    }
+
+
+    /**
+     * This class populate LevelsEditGUI with main level settings.
+     * @param panelBuilder PanelBuilder where icons must be added.
+     */
+    private void buildMainPropertiesPanel(PanelBuilder panelBuilder)
+    {
+        panelBuilder.listener(new IconChanger());
+
+        panelBuilder.item(10, this.createButton(Button.NAME));
+
+        panelBuilder.item(19, this.createButton(Button.ICON));
+        panelBuilder.item(28, this.createButton(Button.LOCKED_ICON));
+        panelBuilder.item(22, this.createButton(Button.DESCRIPTION));
+        panelBuilder.item(25, this.createButton(Button.ORDER));
+
+        panelBuilder.item(31, this.createButton(Button.WAIVER_AMOUNT));
+    }
+
+
+    /**
+     * This class populate LevelsEditGUI with level rewards.
+     * @param panelBuilder PanelBuilder where icons must be added.
+     */
+    private void buildRewardsPanel(PanelBuilder panelBuilder)
+    {
+        panelBuilder.item(12, this.createButton(Button.REWARD_TEXT));
+        panelBuilder.item(21, this.createButton(Button.REWARD_COMMANDS));
+
+        panelBuilder.item(13, this.createButton(Button.REWARD_ITEMS));
+        panelBuilder.item(22, this.createButton(Button.REWARD_EXPERIENCE));
+        panelBuilder.item(31, this.createButton(Button.REWARD_MONEY));
+    }
+
+
+    /**
+     * This class populate LevelsEditGUI with level challenges.
+     * @param panelBuilder PanelBuilder where icons must be added.
+     */
+    private void buildChallengesPanel(PanelBuilder panelBuilder)
+    {
+        List<Challenge> challengeList = this.addon.getChallengesManager().getLevelChallenges(this.challengeLevel);
+
+        this.populateElements(panelBuilder,
+            challengeList,
+            o -> this.createChallengeIcon((Challenge) o));
+
+        panelBuilder.item(39, this.createButton(Button.ADD_CHALLENGES));
+        panelBuilder.item(41, this.createButton(Button.REMOVE_CHALLENGES));
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Other methods
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * This method creates top menu buttons, that allows to switch "tabs".
+     * @param menuType Menu Type which button must be constructed.
+     * @return PanelItem that represents given menu type.
+     */
+    private PanelItem createMenuButton(MenuType menuType)
+    {
+        final String reference = Constants.BUTTON + menuType.name().toLowerCase() + ".";
+
+        final String name = this.user.getTranslation(reference + "name");
+        final List<String> description = new ArrayList<>(3);
+        description.add(this.user.getTranslation(reference + "description"));
+        description.add("");
+        description.add(this.user.getTranslation(Constants.TIPS + "click-to-select"));
+
+        ItemStack icon;
+        boolean glow;
+        PanelItem.ClickHandler clickHandler;
+
+        switch (menuType)
+        {
+            case PROPERTIES -> {
+                icon = new ItemStack(Material.CRAFTING_TABLE);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    this.currentMenuType = MenuType.PROPERTIES;
+                    this.build();
+
+                    return true;
+                };
+                glow = this.currentMenuType.equals(MenuType.PROPERTIES);
+            }
+            case CHALLENGES -> {
+                icon = new ItemStack(Material.RAIL);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    this.currentMenuType = MenuType.CHALLENGES;
+                    this.build();
+
+                    return true;
+                };
+                glow = this.currentMenuType.equals(MenuType.CHALLENGES);
+            }
+            case REWARDS -> {
+                icon = new ItemStack(Material.DROPPER);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    this.currentMenuType = MenuType.REWARDS;
+                    this.build();
+
+                    return true;
+                };
+                glow = this.currentMenuType.equals(MenuType.REWARDS);
+            }
+            default -> {
+                icon = new ItemStack(Material.PAPER);
+                clickHandler = null;
+                glow = false;
+            }
+        }
+
+        return new PanelItemBuilder().
+            icon(icon).
+            name(name).
+            description(description).
+            glow(glow).
+            clickHandler(clickHandler).
+            build();
+    }
+
+
+    /**
+     * This method creates given challenge icon. On click it should open Edit Challenge GUI.
+     * @param challenge Challenge which icon must be created.
+     * @return PanelItem that represents given challenge.
+     */
+    private PanelItem createChallengeIcon(Challenge challenge)
+    {
+        return new PanelItemBuilder().
+            name(Util.translateColorCodes(challenge.getFriendlyName())).
+            description(this.generateChallengeDescription(challenge, null)).
+            description("").
+            description(this.user.getTranslation(Constants.TIPS + "click-to-edit")).
+            icon(challenge.getIcon()).
+            clickHandler((panel, user, clickType, slot) -> {
+                // Open challenges edit screen.
+                EditChallengePanel.open(this, challenge);
+                return true;
+            }).
+            glow(!challenge.isDeployed()).
+            build();
+    }
+
+
+    /**
+     * This method creates buttons for default main menu.
+     * @param button Button which panel item must be created.
+     * @return PanelItem that represents given button.
+     */
+    private PanelItem createButton(Button button)
+    {
+        final String reference = Constants.BUTTON + button.name().toLowerCase() + ".";
+
+        final String name = this.user.getTranslation(reference + "name");
+        final List<String> description = new ArrayList<>(3);
+        description.add(this.user.getTranslation(reference + "description"));
+
+        ItemStack icon;
+        boolean glow;
+        PanelItem.ClickHandler clickHandler;
+
+        switch (button)
+        {
+            case REWARD_TEXT -> {
+                icon = new ItemStack(Material.WRITTEN_BOOK);
+
+                description.add(this.user.getTranslation(reference + "value"));
+                description.add(this.challengeLevel.getRewardText());
+
+                clickHandler = (panel, user, clickType, i) ->
+                {
+                    // Create consumer that process description change
+                    Consumer<List<String>> consumer = value ->
+                    {
+                        if (value != null)
+                        {
+                            this.challengeLevel.setRewardText(String.join("\n", value));
+                        }
+
+                        this.build();
+                    };
+
+                    if (!this.challengeLevel.getRewardText().isEmpty() && clickType.isShiftClick())
+                    {
+                        // Reset to the empty value
+                        consumer.accept(Collections.emptyList());
+                    }
+                    else
+                    {
+                        // start conversation
+                        ConversationUtils.createStringListInput(consumer,
+                            user,
+                            user.getTranslation(Constants.CONVERSATIONS + "write-reward-text"),
+                            user.getTranslation(Constants.CONVERSATIONS + "reward-text-changed"));
+                    }
+
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+
+                if (!this.challengeLevel.getRewardText().isEmpty())
+                {
+                    description.add(this.user.getTranslation(Constants.TIPS + "shift-click-to-reset"));
+                }
+            }
+            case REWARD_ITEMS -> {
+
+                if (this.challengeLevel.getRewardItems().isEmpty())
+                {
+                    description.add(this.user.getTranslation(reference + "none"));
+                }
+                else
+                {
+                    description.add(this.user.getTranslation(reference + "title"));
+
+                    Utils.groupEqualItems(this.challengeLevel.getRewardItems()).stream().
+                        sorted(Comparator.comparing(ItemStack::getType)).
+                        forEach(itemStack ->
+                            description.add(this.user.getTranslationOrNothing(reference + "list",
+                                "[item]", Utils.prettifyObject(itemStack, this.user))));
+                }
+
+                icon = new ItemStack(Material.CHEST);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    ItemSelector.open(this.user,
+                        this.challengeLevel.getRewardItems(),
+                        (status, value) -> {
+                            if (status)
+                            {
+                                this.challengeLevel.setRewardItems(value);
+                            }
+
+                            this.build();
+                        });
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+            }
+            case REWARD_EXPERIENCE -> {
+                description.add(this.user.getTranslation(reference + "value",
+                    Constants.NUMBER, String.valueOf(this.challengeLevel.getRewardExperience())));
+                icon = new ItemStack(Material.EXPERIENCE_BOTTLE);
+                clickHandler = (panel, user, clickType, i) -> {
+                    Consumer<Number> numberConsumer = number -> {
+                        if (number != null)
+                        {
+                            this.challengeLevel.setRewardExperience(number.intValue());
+                        }
+
+                        // reopen panel
+                        this.build();
+                    };
+                    ConversationUtils.createNumericInput(numberConsumer,
+                        this.user,
+                        this.user.getTranslation(Constants.CONVERSATIONS + "input-number"),
+                        0,
+                        Integer.MAX_VALUE);
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+            }
+            case REWARD_MONEY -> {
+                description.add(this.user.getTranslation(reference + "value",
+                    Constants.NUMBER, String.valueOf(this.challengeLevel.getRewardMoney())));
+                icon = new ItemStack(this.addon.isEconomyProvided() ? Material.GOLD_INGOT : Material.BARRIER);
+                clickHandler = (panel, user, clickType, i) -> {
+                    Consumer<Number> numberConsumer = number -> {
+                        if (number != null)
+                        {
+                            this.challengeLevel.setRewardMoney(number.doubleValue());
+                        }
+
+                        // reopen panel
+                        this.build();
+                    };
+                    ConversationUtils.createNumericInput(numberConsumer,
+                        this.user,
+                        this.user.getTranslation(Constants.CONVERSATIONS + "input-number"),
+                        0,
+                        Double.MAX_VALUE);
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+            }
+            case REWARD_COMMANDS -> {
+                icon = new ItemStack(Material.COMMAND_BLOCK);
+
+                description.add(this.user.getTranslation(reference + "value"));
+                description.addAll(this.challengeLevel.getRewardCommands());
+
+                clickHandler = (panel, user, clickType, i) ->
+                {
+                    // Create consumer that process description change
+                    Consumer<List<String>> consumer = value ->
+                    {
+                        if (value != null)
+                        {
+                            this.challengeLevel.setRewardCommands(value);
+                        }
+
+                        this.build();
+                    };
+
+                    if (!this.challengeLevel.getRewardCommands().isEmpty() && clickType.isShiftClick())
+                    {
+                        // Reset to the empty value
+                        consumer.accept(Collections.emptyList());
+                    }
+                    else
+                    {
+                        // start conversation
+                        ConversationUtils.createStringListInput(consumer,
+                            user,
+                            user.getTranslation(Constants.CONVERSATIONS + "write-reward-commands"),
+                            user.getTranslation(Constants.CONVERSATIONS + "reward-commands-changed"));
+                    }
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+
+                if (!this.challengeLevel.getRewardCommands().isEmpty())
+                {
+                    description.add(this.user.getTranslation(Constants.TIPS + "shift-click-to-reset"));
+                }
+            }
+            case NAME -> {
+                description.add(this.user.getTranslation(reference + "value",
+                    "[name]", this.challengeLevel.getFriendlyName()));
+
+                icon = new ItemStack(Material.NAME_TAG);
+
+                clickHandler = (panel, user, clickType, i) ->
+                {
+                    // Create consumer that process description change
+                    Consumer<String> consumer = value ->
+                    {
+                        if (value != null)
+                        {
+                            this.challengeLevel.setFriendlyName(value);
+                        }
+
+                        this.build();
+                    };
+
+                    // start conversation
+                    ConversationUtils.createStringInput(consumer,
+                        user,
+                        user.getTranslation(Constants.CONVERSATIONS + "write-name"),
+                        user.getTranslation(Constants.CONVERSATIONS + "name-changed"));
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+            }
+            case DESCRIPTION -> {
+                icon = new ItemStack(Material.WRITTEN_BOOK);
+
+                description.add(this.user.getTranslation(reference + "value"));
+                description.add(this.challengeLevel.getUnlockMessage());
+
+                clickHandler = (panel, user, clickType, i) ->
+                {
+                    // Create consumer that process description change
+                    Consumer<List<String>> consumer = value ->
+                    {
+                        if (value != null)
+                        {
+                            this.challengeLevel.setUnlockMessage(String.join("\n", value));
+                        }
+
+                        this.build();
+                    };
+
+                    if (!this.challengeLevel.getUnlockMessage().isEmpty() && clickType.isShiftClick())
+                    {
+                        // Reset to the empty value
+                        consumer.accept(Collections.emptyList());
+                    }
+                    else
+                    {
+                        // start conversation
+                        ConversationUtils.createStringListInput(consumer,
+                            user,
+                            user.getTranslation(Constants.CONVERSATIONS + "write-description"),
+                            user.getTranslation(Constants.CONVERSATIONS + "description-changed"));
+                    }
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+
+                if (!this.challengeLevel.getUnlockMessage().isEmpty())
+                {
+                    description.add(this.user.getTranslation(Constants.TIPS + "shift-click-to-reset"));
+                }
+            }
+            case ICON, LOCKED_ICON -> {
+                icon = button == Button.LOCKED_ICON ?
+                    this.challengeLevel.getLockedIcon() :
+                    this.challengeLevel.getIcon();
+
+                clickHandler = (panel, user, clickType, i) ->
+                {
+                    this.selectedButton = button;
+                    this.build();
+                    return true;
+                };
+
+                if (this.selectedButton != button)
+                {
+                    description.add("");
+                    description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+                }
+                else
+                {
+                    description.add("");
+                    description.add(this.user.getTranslation(Constants.TIPS + "click-on-item"));
+                }
+
+                glow = this.selectedButton == button;
+            }
+            case ORDER -> {
+                description.add(this.user.getTranslation(reference + "value",
+                    Constants.NUMBER, String.valueOf(this.challengeLevel.getOrder())));
+
+                icon = new ItemStack(Material.HOPPER, Math.max(1, this.challengeLevel.getOrder()));
+                clickHandler = (panel, user, clickType, i) -> {
+                    Consumer<Number> numberConsumer = number -> {
+                        if (number != null)
+                        {
+                            this.challengeLevel.setOrder(number.intValue());
+                        }
+
+                        // reopen panel
+                        this.build();
+                    };
+
+                    ConversationUtils.createNumericInput(numberConsumer,
+                        this.user,
+                        this.user.getTranslation(Constants.CONVERSATIONS + "input-number"),
+                        0,
+                        2000);
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+            }
+            case WAIVER_AMOUNT -> {
+                description.add(this.user.getTranslation(reference + "value",
+                    Constants.NUMBER, String.valueOf(this.challengeLevel.getWaiverAmount())));
+
+                icon = new ItemStack(Material.HOPPER, Math.max(1, this.challengeLevel.getWaiverAmount()));
+                clickHandler = (panel, user, clickType, i) -> {
+                    Consumer<Number> numberConsumer = number -> {
+                        if (number != null)
+                        {
+                            this.challengeLevel.setWaiverAmount(number.intValue());
+                        }
+
+                        // reopen panel
+                        this.build();
+                    };
+
+                    ConversationUtils.createNumericInput(numberConsumer,
+                        this.user,
+                        this.user.getTranslation(Constants.CONVERSATIONS + "input-number"),
+                        0,
+                        2000);
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+            }
+            case ADD_CHALLENGES -> {
+                icon = new ItemStack(Material.WATER_BUCKET);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    ChallengesManager manager = this.addon.getChallengesManager();
+
+                    // Get all challenge that is not in current level.
+                    List<Challenge> challengeList = manager.getAllChallenges(this.world);
+                    challengeList.removeAll(manager.getLevelChallenges(this.challengeLevel));
+
+                    // Generate descriptions for these challenges
+                    Map<Challenge, List<String>> challengeDescriptionMap = challengeList.stream().
+                        collect(Collectors.toMap(challenge -> challenge,
+                            challenge -> this.generateChallengeDescription(challenge, null),
+                            (a, b) -> b,
+                            () -> new LinkedHashMap<>(challengeList.size())));
+
+                    // Open select gui
+                    ChallengeSelector.open(this.user,
+                        Material.BLUE_STAINED_GLASS_PANE,
+                        challengeDescriptionMap,
+                        (status, valueSet) -> {
+                            if (status)
+                            {
+                                valueSet.forEach(challenge ->
+                                    manager.addChallengeToLevel(challenge, this.challengeLevel));
+                            }
+
+                        this.build();
+                    });
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-add"));
+            }
+            case REMOVE_CHALLENGES -> {
+                icon = new ItemStack(Material.LAVA_BUCKET);
+                clickHandler = (panel, user, clickType, slot) -> {
+                    ChallengesManager manager = this.addon.getChallengesManager();
+
+                    // Get all challenge that is in current level.
+                    List<Challenge> challengeList = manager.getLevelChallenges(this.challengeLevel);
+
+                    // Generate descriptions for these challenges
+                    Map<Challenge, List<String>> challengeDescriptionMap = challengeList.stream().
+                        collect(Collectors.toMap(challenge -> challenge,
+                            challenge -> this.generateChallengeDescription(challenge, null),
+                            (a, b) -> b,
+                            () -> new LinkedHashMap<>(challengeList.size())));
+
+                    // Open select gui
+                    ChallengeSelector.open(this.user,
+                        Material.RED_STAINED_GLASS_PANE,
+                        challengeDescriptionMap,
+                        (status, valueSet) -> {
+                            if (status)
+                            {
+                                valueSet.forEach(challenge ->
+                                    manager.removeChallengeFromLevel(challenge, this.challengeLevel));
+                            }
+
+                        this.build();
+                    });
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-remove"));
+            }
+            default -> {
+                icon = new ItemStack(Material.PAPER);
+                clickHandler = null;
+                glow = false;
+            }
+        }
+
+        return new PanelItemBuilder().
+            icon(icon).
+            name(name).
+            description(description).
+            glow(glow).
+            clickHandler(clickHandler).
+            build();
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Classes
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * This class allows changing icon for Generator Tier
+     */
+    private class IconChanger implements PanelListener
+    {
+        /**
+         * Process inventory click. If generator icon is selected and user clicks on item in his inventory, then change
+         * icon to the item from inventory.
+         *
+         * @param user the user
+         * @param event the event
+         */
+        @Override
+        public void onInventoryClick(User user, InventoryClickEvent event)
+        {
+            // Handle icon changing
+            if (EditLevelPanel.this.selectedButton != null &&
+                event.getCurrentItem() != null &&
+                !event.getCurrentItem().getType().equals(Material.AIR) &&
+                event.getRawSlot() > 44)
+            {
+                // set material and amount only. Other data should be removed.
+
+                if (EditLevelPanel.this.selectedButton == Button.ICON)
+                {
+                    EditLevelPanel.this.challengeLevel.setIcon(event.getCurrentItem().clone());
+                    // Deselect icon
+                    EditLevelPanel.this.selectedButton = null;
+                    // Rebuild icon
+                    EditLevelPanel.this.build();
+                }
+                else if (EditLevelPanel.this.selectedButton == Button.LOCKED_ICON)
+                {
+                    EditLevelPanel.this.challengeLevel.setLockedIcon(event.getCurrentItem().clone());
+                    // Deselect icon
+                    EditLevelPanel.this.selectedButton = null;
+                    // Rebuild icon
+                    EditLevelPanel.this.build();
+                }
+            }
+        }
+
+
+        /**
+         * On inventory close.
+         *
+         * @param event the event
+         */
+        @Override
+        public void onInventoryClose(InventoryCloseEvent event)
+        {
+            // Do nothing
+        }
+
+
+        /**
+         * Setup current listener.
+         */
+        @Override
+        public void setup()
+        {
+            // Do nothing
+        }
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Enums
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * Represents different buttons that could be in menus.
+     */
+    private enum Button
+    {
+        NAME,
+        ICON,
+        LOCKED_ICON,
+        DESCRIPTION,
+        ORDER,
+        WAIVER_AMOUNT,
+
+        REWARD_TEXT,
+        REWARD_ITEMS,
+        REWARD_EXPERIENCE,
+        REWARD_MONEY,
+        REWARD_COMMANDS,
+
+        ADD_CHALLENGES,
+        REMOVE_CHALLENGES
+    }
+
+
+    /**
+     * Represents different types of menus
+     */
+    private enum MenuType
+    {
+        PROPERTIES,
+        CHALLENGES,
+        REWARDS
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Variables
+    // ---------------------------------------------------------------------
+
+    /**
+     * This variable holds current challenge level that is in editing GUI.
+     */
+    private final ChallengeLevel challengeLevel;
+
+    /**
+     * Variable holds current active menu.
+     */
+    private MenuType currentMenuType;
+
+    private Button selectedButton;
+}

src/main/java/world/bentobox/challenges/panel/admin/EditLoreGUI.java

@@ -1,638 +0,0 @@
-package world.bentobox.challenges.panel.admin;
-
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-import java.util.function.BiConsumer;
-import java.util.function.Consumer;
-import java.util.stream.Collectors;
-
-import org.bukkit.Material;
-import org.bukkit.event.inventory.InventoryClickEvent;
-import org.bukkit.event.inventory.InventoryCloseEvent;
-import org.bukkit.inventory.ItemStack;
-import org.eclipse.jdt.annotation.Nullable;
-
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.PanelListener;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.config.SettingsUtils.ChallengeLore;
-import world.bentobox.challenges.config.SettingsUtils.LevelLore;
-import world.bentobox.challenges.panel.CommonGUI;
-import world.bentobox.challenges.utils.GuiUtils;
-
-
-/**
- * This class allows to change Input ItemStacks to different ItemStacks.
- */
-public class EditLoreGUI extends CommonGUI
-{
-    public EditLoreGUI(CommonGUI parent, LoreType loreType)
-    {
-        super(parent);
-
-        this.lore = loreType;
-        this.activeValues = new ArrayList<>();
-
-        switch (this.lore)
-        {
-        case CHALLENGES:
-
-            for (ChallengeLore lore : this.addon.getChallengesSettings().getChallengeLoreMessage())
-            {
-                this.activeValues.add(lore.name());
-            }
-
-            break;
-        case LEVELS:
-
-            for (LevelLore lore : this.addon.getChallengesSettings().getLevelLoreMessage())
-            {
-                this.activeValues.add(lore.name());
-            }
-
-            break;
-        }
-    }
-
-
-    /**
-     * This is static call method for easier GUI opening.
-     * @param parent Parent GUI.
-     * @param loreType loreType that will be edited.
-     */
-    public static void open(CommonGUI parent, LoreType loreType)
-    {
-        new EditLoreGUI(parent, loreType).build();
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Methods
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * This method builds panel that allows to change given number value.
-     */
-    @Override
-    public void build()
-    {
-        PanelBuilder panelBuilder = new PanelBuilder().
-                name(this.user.getTranslation("challenges.gui.title.admin.lore-edit")).
-                user(this.user).
-                listener(new CustomPanelListener());
-
-        GuiUtils.fillBorder(panelBuilder, 5, Material.MAGENTA_STAINED_GLASS_PANE);
-
-        // Define all active buttons
-        panelBuilder.item(1, this.getButton(Button.SAVE));
-
-        panelBuilder.item(3, this.getButton(Button.ADD));
-        panelBuilder.item(4, this.getButton(Button.REMOVE));
-
-        // TODO: Need 2 View Buttons
-        // One for closes / One for opened.
-        //		panelBuilder.item(6, this.getButton(Button.VIEW));
-
-        panelBuilder.item(44, this.returnButton);
-
-        // necessary as I have a border around this GUI
-        int currentIndex = 10;
-
-        // Only 21 elements will be displayed. On porpoise!
-        for (int i = 0; i < this.activeValues.size() || i > 21; i++)
-        {
-            panelBuilder.item(currentIndex++, this.getLoreButton(this.activeValues.get(i)));
-
-            // Border element
-            if (currentIndex % 9 == 8)
-            {
-                currentIndex += 2;
-            }
-
-            // Just in case. Should never occur.
-            if (currentIndex % 9 == 0)
-            {
-                currentIndex++;
-            }
-        }
-
-        panelBuilder.build();
-    }
-
-
-    /**
-     * This method create button that does some functionality in current gui.
-     * @param button Button functionality.
-     * @return PanelItem.
-     */
-    private PanelItem getButton(Button button)
-    {
-        ItemStack icon;
-        String name;
-        List<String> description;
-        PanelItem.ClickHandler clickHandler;
-
-        switch (button)
-        {
-        case SAVE:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.save");
-            description = Collections.emptyList();
-            icon = new ItemStack(Material.COMMAND_BLOCK);
-            clickHandler = (panel, user, clickType, slot) -> {
-
-                switch (this.lore)
-                {
-                case CHALLENGES:
-                {
-                    List<ChallengeLore> lore = this.activeValues.stream().
-                            map(ChallengeLore::valueOf).
-                            collect(Collectors.toCollection(() -> new ArrayList<>(this.activeValues.size())));
-
-                    this.addon.getChallengesSettings().setChallengeLoreMessage(lore);
-
-                    break;
-                }
-                case LEVELS:
-                {
-                    List<LevelLore> lore = this.activeValues.stream().
-                            map(LevelLore::valueOf).
-                            collect(Collectors.toCollection(() -> new ArrayList<>(this.activeValues.size())));
-
-                    this.addon.getChallengesSettings().setLevelLoreMessage(lore);
-
-                    break;
-                }
-                }
-
-                // Save and return to parent gui.
-                this.parentGUI.build();
-
-                return true;
-            };
-            break;
-        }
-        case ADD:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.add");
-            description = Collections.emptyList();
-            icon = new ItemStack(Material.GREEN_STAINED_GLASS_PANE);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new AddLoreElementGUI(element -> {
-                    this.activeValues.add(element);
-                    this.build();
-                });
-
-                return true;
-            };
-
-            break;
-        }
-        case REMOVE:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.remove-selected");
-            description = Collections.emptyList();
-            icon = new ItemStack(Material.RED_STAINED_GLASS_PANE);
-            clickHandler = (panel, user, clickType, slot) -> {
-                new RemoveLoreElementGUI((element, index) -> {
-                    if (this.activeValues.get(index).equals(element))
-                    {
-                        this.activeValues.remove(element);
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-
-            break;
-        }
-        case VIEW:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.view");
-            description = Collections.emptyList();
-            icon = new ItemStack(Material.YELLOW_STAINED_GLASS_PANE);
-            clickHandler = (panel, user, clickType, slot) -> {
-                return true;
-            };
-
-            break;
-        }
-        default:
-            return null;
-        }
-
-        return new PanelItemBuilder().
-                icon(icon).
-                name(name).
-                description(GuiUtils.stringSplit(description, this.addon.getChallengesSettings().getLoreLineLength())).
-                glow(false).
-                clickHandler(clickHandler).
-                build();
-    }
-
-
-    /**
-     * This method creates button for lore element.
-     * @param loreElement String that represents current lore element.
-     * @return PanelItem.
-     */
-    @Nullable
-    private PanelItem getLoreButton(String loreElement)
-    {
-        switch (this.lore)
-        {
-        case CHALLENGES:
-            return this.getChallengeLoreButton(loreElement);
-        case LEVELS:
-            return this.getLevelLoreButton(loreElement);
-        default:
-            // this should never happen!
-            return null;
-        }
-    }
-
-
-    /**
-     * This method creates button for challenge lore element.
-     * @param loreElement String that represents current challenge lore element.
-     * @return PanelItem.
-     */
-    private PanelItem getChallengeLoreButton(String loreElement)
-    {
-        Material icon;
-        String name = loreElement;
-        List<String> description = new ArrayList<>();
-        description.add(this.user.getTranslation(REFERENCE_DESCRIPTION + "lore." + loreElement.toLowerCase()));
-
-        PanelItem.ClickHandler clickHandler = (panel, user1, clickType, slot) -> true;
-
-        switch (ChallengeLore.valueOf(loreElement))
-        {
-        case LEVEL:
-        {
-            icon = Material.DIRT;
-            break;
-        }
-        case STATUS:
-        {
-            icon = Material.LEVER;
-            break;
-        }
-        case COUNT:
-        {
-            icon = Material.REPEATER;
-            break;
-        }
-        case DESCRIPTION:
-        {
-            icon = Material.WRITTEN_BOOK;
-            break;
-        }
-        case WARNINGS:
-        {
-            icon = Material.LAVA_BUCKET;
-            break;
-        }
-        case ENVIRONMENT:
-        {
-            icon = Material.GLASS;
-            break;
-        }
-        case REQUIREMENTS:
-        {
-            icon = Material.HOPPER;
-            break;
-        }
-        case REWARD_TEXT:
-        {
-            icon = Material.PAPER;
-            break;
-        }
-        case REWARD_OTHER:
-        {
-            icon = Material.CHEST;
-            break;
-        }
-        case REWARD_ITEMS:
-        {
-            icon = Material.TRAPPED_CHEST;
-            break;
-        }
-        case REWARD_COMMANDS:
-        {
-            icon = Material.COMMAND_BLOCK;
-            break;
-        }
-        default:
-        {
-            icon = Material.BARRIER;
-            break;
-        }
-        }
-
-        return new PanelItemBuilder().
-                name(name).
-                icon(icon).
-                description(GuiUtils.stringSplit(description, this.addon.getChallengesSettings().getLoreLineLength())).
-                clickHandler(clickHandler).
-                glow(false).
-                build();
-    }
-
-
-    /**
-     * This method creates button for challenge level lore element.
-     * @param loreElement String that represents current challenge level lore element.
-     * @return PanelItem.
-     */
-    private PanelItem getLevelLoreButton(String loreElement)
-    {
-        Material icon;
-        String name = loreElement;
-        List<String> description = new ArrayList<>();
-        description.add(this.user.getTranslation(REFERENCE_DESCRIPTION + "lore." + loreElement.toLowerCase()));
-
-        PanelItem.ClickHandler clickHandler = (panel, user1, clickType, slot) -> true;
-
-        switch (LevelLore.valueOf(loreElement))
-        {
-        case LEVEL_STATUS:
-        {
-            icon = Material.DIRT;
-            break;
-        }
-        case CHALLENGE_COUNT:
-        {
-            icon = Material.REPEATER;
-            break;
-        }
-        case UNLOCK_MESSAGE:
-        {
-            icon = Material.WRITTEN_BOOK;
-            break;
-        }
-        case WAIVER_AMOUNT:
-        {
-            icon = Material.COMPARATOR;
-            break;
-        }
-        case LEVEL_REWARD_TEXT:
-        {
-            icon = Material.PAPER;
-            break;
-        }
-        case LEVEL_REWARD_OTHER:
-        {
-            icon = Material.CHEST;
-            break;
-        }
-        case LEVEL_REWARD_ITEMS:
-        {
-            icon = Material.TRAPPED_CHEST;
-            break;
-        }
-        case LEVEL_REWARD_COMMANDS:
-        {
-            icon = Material.COMMAND_BLOCK;
-            break;
-        }
-        default:
-        {
-            icon = Material.BARRIER;
-            break;
-        }
-        }
-
-        return new PanelItemBuilder().
-                name(name).
-                icon(icon).
-                description(GuiUtils.stringSplit(description, this.addon.getChallengesSettings().getLoreLineLength())).
-                clickHandler(clickHandler).
-                glow(false).
-                build();
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Select GUI
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * This class opens new GUI that add an element from all available lore values.
-     */
-    private class AddLoreElementGUI
-    {
-        private AddLoreElementGUI(Consumer<String> selectedElement)
-        {
-            PanelBuilder panelBuilder = new PanelBuilder().
-                    name(EditLoreGUI.this.user.getTranslation("challenges.gui.title.admin.lore-add")).
-                    user(EditLoreGUI.this.user);
-
-            GuiUtils.fillBorder(panelBuilder, 5, Material.MAGENTA_STAINED_GLASS_PANE);
-
-            int currentIndex = 10;
-
-            List<String> values = new ArrayList<>();
-
-            // Populate list with all elements.
-            switch (EditLoreGUI.this.lore)
-            {
-            case CHALLENGES:
-                for (ChallengeLore value : ChallengeLore.values())
-                {
-                    values.add(value.name());
-                }
-                break;
-            case LEVELS:
-                for (LevelLore value : LevelLore.values())
-                {
-                    values.add(value.name());
-                }
-                break;
-            }
-
-            for (String value : values)
-            {
-                PanelItem item = EditLoreGUI.this.getLoreButton(value);
-                if (item != null) {
-                    item.setClickHandler((panel, user1, clickType, slot) -> {
-                        selectedElement.accept(value);
-                        return true;
-                    });
-
-                    panelBuilder.item(currentIndex++, item);
-
-
-                    // Border element
-                    if (currentIndex % 9 == 8)
-                    {
-                        currentIndex += 2;
-                    }
-
-                    // Just in case. Should never occur.
-                    if (currentIndex % 9 == 0)
-                    {
-                        currentIndex++;
-                    }
-
-                    // Just in case. Should never occur.
-                    if (currentIndex > 35)
-                    {
-                        break;
-                    }
-                }
-            }
-
-            panelBuilder.build();
-        }
-    }
-
-
-    /**
-     * This class opens new GUI that remove an element from all available lore values.
-     */
-    private class RemoveLoreElementGUI
-    {
-        private RemoveLoreElementGUI(BiConsumer<String, Integer> selectedElement)
-        {
-            PanelBuilder panelBuilder = new PanelBuilder().
-                    name(EditLoreGUI.this.user.getTranslation("challenges.gui.title.admin.lore-remove")).
-                    user(EditLoreGUI.this.user);
-
-            GuiUtils.fillBorder(panelBuilder, 5, Material.MAGENTA_STAINED_GLASS_PANE);
-
-            int currentIndex = 10;
-
-            List<String> values = EditLoreGUI.this.activeValues;
-
-            for (int i = 0; i < values.size(); i++)
-            {
-                final int counter = i;
-
-                String value = values.get(counter);
-                PanelItem item = EditLoreGUI.this.getLoreButton(value);
-                if (item != null) {
-                    item.setClickHandler((panel, user1, clickType, slot) -> {
-                        selectedElement.accept(value, counter);
-                        return true;
-                    });
-
-                    panelBuilder.item(currentIndex++, item);
-
-                    // Border element
-                    if (currentIndex % 9 == 8)
-                    {
-                        currentIndex += 2;
-                    }
-
-                    // Just in case. Should never occur.
-                    if (currentIndex % 9 == 0)
-                    {
-                        currentIndex++;
-                    }
-
-                    // Just in case. Should never occur.
-                    if (currentIndex > 35)
-                    {
-                        break;
-                    }
-                }
-            }
-
-            panelBuilder.build();
-        }
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Private classes
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * This CustomPanelListener allows to move items in current panel.
-     */
-    private class CustomPanelListener implements PanelListener
-    {
-        @Override
-        public void setup()
-        {
-        }
-
-
-        @Override
-        public void onInventoryClose(InventoryCloseEvent inventoryCloseEvent)
-        {
-        }
-
-
-        @Override
-        public void onInventoryClick(User user, InventoryClickEvent event)
-        {
-            // First row of elements should be ignored, as it contains buttons and blocked slots.
-            event.setCancelled(event.getRawSlot() < 9 ||
-                    event.getRawSlot() < 35 ||
-                    event.getRawSlot() % 9 == 0 ||
-                    event.getRawSlot() % 9 == 8);
-        }
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Enums
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * This enum holds all button values in current gui.
-     */
-    private enum Button
-    {
-        SAVE,
-        ADD,
-        REMOVE,
-        VIEW,
-        RETURN
-    }
-
-
-    /**
-     * This enum holds which Lore is edited with current GUI.
-     */
-    public enum LoreType
-    {
-        CHALLENGES,
-        LEVELS,
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Variables
-    // ---------------------------------------------------------------------
-
-    /**
-     * Lore that will be edited with current GUI.
-     */
-    private final LoreType lore;
-
-    /**
-     * List of lore elements that are currently enabled.
-     */
-    private List<String> activeValues;
-
-
-    // ---------------------------------------------------------------------
-    // Section: Constants
-    // ---------------------------------------------------------------------
-
-
-    private final static String REFERENCE_DESCRIPTION = "challenges.gui.descriptions.admin.";
-}

src/main/java/world/bentobox/challenges/panel/admin/EditSettingsGUI.java

@@ -1,606 +0,0 @@
-package world.bentobox.challenges.panel.admin;
-
-
-import java.util.ArrayList;
-import java.util.List;
-
-import org.bukkit.Material;
-import org.bukkit.World;
-import org.bukkit.inventory.ItemStack;
-
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.ChallengesAddon;
-import world.bentobox.challenges.config.Settings;
-import world.bentobox.challenges.config.SettingsUtils.GuiMode;
-import world.bentobox.challenges.config.SettingsUtils.VisibilityMode;
-import world.bentobox.challenges.panel.CommonGUI;
-import world.bentobox.challenges.panel.util.NumberGUI;
-import world.bentobox.challenges.panel.util.SelectBlocksGUI;
-import world.bentobox.challenges.utils.GuiUtils;
-import world.bentobox.challenges.utils.Utils;
-
-
-/**
- * This Class creates GUI that allows to change Challenges Addon Settings via in-game
- * menu.
- */
-public class EditSettingsGUI extends CommonGUI
-{
-    // ---------------------------------------------------------------------
-    // Section: Constructors
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * @param addon Addon where panel operates.
-     * @param world World from which panel was created.
-     * @param user User who created panel.
-     * @param topLabel Command top label which creates panel (f.e. island or ai)
-     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
-     */
-    public EditSettingsGUI(ChallengesAddon addon,
-            World world,
-            User user,
-            String topLabel,
-            String permissionPrefix)
-    {
-        this(addon, world, user, topLabel, permissionPrefix, null);
-    }
-
-
-    /**
-     * @param addon Addon where panel operates.
-     * @param world World from which panel was created.
-     * @param user User who created panel.
-     * @param topLabel Command top label which creates panel (f.e. island or ai)
-     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
-     */
-    public EditSettingsGUI(ChallengesAddon addon,
-            World world,
-            User user,
-            String topLabel,
-            String permissionPrefix,
-            CommonGUI parentGUI)
-    {
-        super(addon, world, user, topLabel, permissionPrefix, parentGUI);
-        this.settings = this.addon.getChallengesSettings();
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Methods
-    // ---------------------------------------------------------------------
-
-
-    @Override
-    public void build()
-    {
-        PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(
-                this.user.getTranslation("challenges.gui.title.admin.settings-title"));
-
-        GuiUtils.fillBorder(panelBuilder);
-
-        panelBuilder.item(10, this.getSettingsButton(Button.ENABLE_TITLE));
-
-        if (this.settings.isShowCompletionTitle())
-        {
-            panelBuilder.item(19, this.getSettingsButton(Button.TITLE_SHOWTIME));
-        }
-
-        panelBuilder.item(28, this.getSettingsButton(Button.BROADCAST));
-
-        panelBuilder.item(11, this.getSettingsButton(Button.GLOW_COMPLETED));
-        panelBuilder.item(20, this.getSettingsButton(Button.REMOVE_COMPLETED));
-        panelBuilder.item(29, this.getSettingsButton(Button.VISIBILITY_MODE));
-
-        panelBuilder.item(21, this.getSettingsButton(Button.LOCKED_LEVEL_ICON));
-        panelBuilder.item(30, this.getSettingsButton(Button.FREE_AT_TOP));
-
-        panelBuilder.item(22, this.getSettingsButton(Button.GAMEMODE_GUI));
-
-        if (this.settings.isUseCommonGUI())
-        {
-            // This should be active only when single gui is enabled.
-            panelBuilder.item(31, this.getSettingsButton(Button.GAMEMODE_GUI_VIEW_MODE));
-        }
-
-        panelBuilder.item(14, this.getSettingsButton(Button.LORE_LENGTH));
-        panelBuilder.item(23, this.getSettingsButton(Button.CHALLENGE_LORE));
-        panelBuilder.item(32, this.getSettingsButton(Button.LEVEL_LORE));
-
-        panelBuilder.item(24, this.getSettingsButton(Button.HISTORY));
-
-        if (this.settings.isStoreHistory())
-        {
-            panelBuilder.item(33, this.getSettingsButton(Button.PURGE_HISTORY));
-        }
-
-        panelBuilder.item(25, this.getSettingsButton(Button.RESET_CHALLENGES));
-        panelBuilder.item(34, this.getSettingsButton(Button.STORE_MODE));
-
-        // Return Button
-        panelBuilder.item(44, this.returnButton);
-
-        // Save Settings every time this GUI is created. It will avoid issues with
-        // Overwritten setting after server stop.
-        this.addon.saveSettings();
-
-        panelBuilder.build();
-    }
-
-
-    private PanelItem getSettingsButton(Button button)
-    {
-        ItemStack icon;
-        String name;
-        List<String> description;
-        boolean glow;
-        PanelItem.ClickHandler clickHandler;
-
-        switch (button)
-        {
-        case RESET_CHALLENGES:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.reset-on-new"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]",
-                    this.settings.isResetChallenges() ?
-                            this.user.getTranslation("challenges.gui.descriptions.enabled") :
-                                this.user.getTranslation("challenges.gui.descriptions.disabled")));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.reset-on-new");
-            icon = new ItemStack(Material.LAVA_BUCKET);
-
-            clickHandler = (panel, user1, clickType, i) -> {
-                this.settings.setResetChallenges(
-                        !this.settings.isResetChallenges());
-
-                panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
-                return true;
-            };
-
-            glow = this.settings.isResetChallenges();
-            break;
-        }
-        case BROADCAST:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.broadcast"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]",
-                    this.settings.isBroadcastMessages() ?
-                            this.user.getTranslation("challenges.gui.descriptions.enabled") :
-                                this.user.getTranslation("challenges.gui.descriptions.disabled")));
-
-            description = new ArrayList<>(2);
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.broadcast");
-            icon = new ItemStack(Material.JUKEBOX);
-            clickHandler = (panel, user1, clickType, i) -> {
-                this.settings.setBroadcastMessages(
-                        !this.settings.isBroadcastMessages());
-                panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
-                return true;
-            };
-            glow = this.settings.isBroadcastMessages();
-
-            break;
-        }
-        case REMOVE_COMPLETED:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.remove-completed"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]",
-                    this.settings.isRemoveCompleteOneTimeChallenges() ?
-                            this.user.getTranslation("challenges.gui.descriptions.enabled") :
-                                this.user.getTranslation("challenges.gui.descriptions.disabled")));
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.remove-completed");
-            icon = new ItemStack(Material.MAGMA_BLOCK);
-            clickHandler = (panel, user1, clickType, i) -> {
-                this.settings.setRemoveCompleteOneTimeChallenges(
-                        !this.settings.isRemoveCompleteOneTimeChallenges());
-                panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
-                return true;
-            };
-            glow = this.settings.isRemoveCompleteOneTimeChallenges();
-
-            break;
-        }
-        case LORE_LENGTH:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.line-length"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]", Integer.toString(this.settings.getLoreLineLength())));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.line-length");
-            icon = new ItemStack(Material.ANVIL);
-            clickHandler = (panel, user1, clickType, i) -> {
-                new NumberGUI(this.user,
-                        this.settings.getLoreLineLength(),
-                        0,
-                        this.settings.getLoreLineLength(),
-                        (status, value) -> {
-                            if (status)
-                            {
-                                this.settings.setLoreLineLength(value);
-                            }
-
-                            panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
-                        });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case LEVEL_LORE:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.level-lore"));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.level-lore");
-            icon = new ItemStack(Material.MAP);
-            clickHandler = (panel, user1, clickType, i) -> {
-
-                EditLoreGUI.open(this, EditLoreGUI.LoreType.LEVELS);
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case CHALLENGE_LORE:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.challenge-lore"));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.challenge-lore");
-            icon = new ItemStack(Material.PAPER);
-            clickHandler = (panel, user1, clickType, i) -> {
-
-                EditLoreGUI.open(this, EditLoreGUI.LoreType.CHALLENGES);
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case FREE_AT_TOP:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.free-at-top"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]",
-                    this.settings.isAddCompletedGlow() ?
-                            this.user.getTranslation("challenges.gui.descriptions.enabled") :
-                                this.user.getTranslation("challenges.gui.descriptions.disabled")));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.free-at-top");
-            icon = new ItemStack(Material.FILLED_MAP);
-            clickHandler = (panel, user1, clickType, i) -> {
-                this.settings.setFreeChallengesFirst(!this.settings.isFreeChallengesFirst());
-                panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
-                return true;
-            };
-            glow = this.settings.isFreeChallengesFirst();
-            break;
-        }
-        case GLOW_COMPLETED:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.glow"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]",
-                    this.settings.isAddCompletedGlow() ?
-                            this.user.getTranslation("challenges.gui.descriptions.enabled") :
-                                this.user.getTranslation("challenges.gui.descriptions.disabled")));
-
-
-            name = this.user.getTranslation("challenges.gui.buttons.admin.glow");
-            icon = new ItemStack(Material.GLOWSTONE);
-            clickHandler = (panel, user1, clickType, i) -> {
-                this.settings.setAddCompletedGlow(!this.settings.isAddCompletedGlow());
-                panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
-                return true;
-            };
-            glow = this.settings.isAddCompletedGlow();
-            break;
-        }
-        case GAMEMODE_GUI_VIEW_MODE:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.gui-view-mode"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]",
-                    this.settings.getUserGuiMode().equals(GuiMode.GAMEMODE_LIST) ?
-                            this.user.getTranslation("challenges.gui.descriptions.enabled") :
-                                this.user.getTranslation("challenges.gui.descriptions.disabled")));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.gui-view-mode");
-            icon = new ItemStack(Material.STONE_BUTTON);
-            clickHandler = (panel, user1, clickType, i) -> {
-
-                if (this.settings.getUserGuiMode().equals(GuiMode.GAMEMODE_LIST))
-                {
-                    this.settings.setUserGuiMode(GuiMode.CURRENT_WORLD);
-                }
-                else
-                {
-                    this.settings.setUserGuiMode(GuiMode.GAMEMODE_LIST);
-                }
-
-                panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
-                return true;
-            };
-            glow = this.settings.getUserGuiMode().equals(GuiMode.GAMEMODE_LIST);
-            break;
-        }
-        case GAMEMODE_GUI:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.gui-mode"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]",
-                    this.settings.isUseCommonGUI() ?
-                            this.user.getTranslation("challenges.gui.descriptions.enabled") :
-                                this.user.getTranslation("challenges.gui.descriptions.disabled")));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.gui-mode");
-            icon = new ItemStack(Material.BLACK_STAINED_GLASS_PANE);
-            clickHandler = (panel, user1, clickType, i) -> {
-                this.settings.setUseCommonGUI(!this.settings.isUseCommonGUI());
-                // We cannot use single item changing as this option enabling/disabling will change other
-                // option visibility.
-                this.build();
-                return true;
-            };
-            glow = this.settings.isUseCommonGUI();
-            break;
-        }
-        case HISTORY:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.history-store"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]",
-                    this.settings.isStoreHistory() ?
-                            this.user.getTranslation("challenges.gui.descriptions.enabled") :
-                                this.user.getTranslation("challenges.gui.descriptions.disabled")));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.history-store");
-            icon = new ItemStack(Material.WRITTEN_BOOK);
-            clickHandler = (panel, user1, clickType, i) -> {
-                this.settings.setStoreHistory(!this.settings.isStoreHistory());
-
-                // Need to rebuild all as new buttons will show up.
-                this.build();
-                return true;
-            };
-            glow = this.settings.isStoreHistory();
-            break;
-        }
-        case PURGE_HISTORY:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.history-lifespan"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]", Integer.toString(this.settings.getLifeSpan())));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.history-lifespan");
-            icon = new ItemStack(Material.FLINT_AND_STEEL);
-            clickHandler = (panel, user1, clickType, i) -> {
-                new NumberGUI(this.user,
-                        this.settings.getLifeSpan(),
-                        0,
-                        this.settings.getLoreLineLength(),
-                        (status, value) -> {
-                            if (status)
-                            {
-                                this.settings.setLifeSpan(value);
-                            }
-
-                            panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
-                        });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case STORE_MODE:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.island-store"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]",
-                    this.settings.isStoreAsIslandData() ?
-                            this.user.getTranslation("challenges.gui.descriptions.enabled") :
-                                this.user.getTranslation("challenges.gui.descriptions.disabled")));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.island-store");
-            icon = new ItemStack(Material.GRASS_BLOCK);
-            clickHandler = (panel, user1, clickType, i) -> {
-                this.settings.setStoreAsIslandData(!this.settings.isStoreAsIslandData());
-                // TODO: Data Migration must be added here.
-                panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
-                return true;
-            };
-            glow = this.settings.isStoreAsIslandData();
-            break;
-        }
-        case LOCKED_LEVEL_ICON:
-        {
-            description = new ArrayList<>(1);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.default-locked-icon"));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.default-locked-icon");
-            icon = this.settings.getLockedLevelIcon();
-            clickHandler = (panel, user, clickType, slot) -> {
-
-                new SelectBlocksGUI(this.user, true, (status, materials) -> {
-                    if (status)
-                    {
-                        materials.forEach(material ->
-                        this.settings.setLockedLevelIcon(new ItemStack(material)));
-                    }
-
-                    this.build();
-                });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case ENABLE_TITLE:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.title-enable"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]",
-                    this.settings.isShowCompletionTitle() ?
-                            this.user.getTranslation("challenges.gui.descriptions.enabled") :
-                                this.user.getTranslation("challenges.gui.descriptions.disabled")));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.title-enable");
-            icon = new ItemStack(Material.OAK_SIGN);
-            clickHandler = (panel, user1, clickType, i) -> {
-                this.settings.setShowCompletionTitle(!this.settings.isShowCompletionTitle());
-
-                // Need to rebuild all as new buttons will show up.
-                this.build();
-                return true;
-            };
-            glow = this.settings.isShowCompletionTitle();
-            break;
-        }
-        case TITLE_SHOWTIME:
-        {
-            description = new ArrayList<>(2);
-            description.add(this.user.getTranslation("challenges.gui.descriptions.admin.title-showtime"));
-            description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]", Integer.toString(this.settings.getTitleShowtime())));
-            name = this.user.getTranslation("challenges.gui.buttons.admin.title-showtime");
-            icon = new ItemStack(Material.CLOCK);
-            clickHandler = (panel, user1, clickType, i) -> {
-                new NumberGUI(this.user,
-                        this.settings.getTitleShowtime(),
-                        0,
-                        this.settings.getLoreLineLength(),
-                        (status, value) -> {
-                            if (status)
-                            {
-                                this.settings.setTitleShowtime(value);
-                            }
-
-                            panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
-                        });
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case VISIBILITY_MODE:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.visibility-mode");
-
-            List<String> values = new ArrayList<>(5);
-            values.add(this.user.getTranslation("challenges.gui.descriptions.admin.visibility-mode"));
-
-            values.add((this.settings.getVisibilityMode().equals(VisibilityMode.VISIBLE) ? "&2" : "&c") +
-                    this.user.getTranslation("challenges.gui.descriptions.visibility.visible"));
-            values.add((this.settings.getVisibilityMode().equals(VisibilityMode.HIDDEN) ? "&2" : "&c") +
-                    this.user.getTranslation("challenges.gui.descriptions.visibility.hidden"));
-            values.add((this.settings.getVisibilityMode().equals(VisibilityMode.TOGGLEABLE) ? "&2" : "&c") +
-                    this.user.getTranslation("challenges.gui.descriptions.visibility.toggleable"));
-
-            values.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-                    "[value]",this.settings.getVisibilityMode().name()));
-
-            description = values;
-
-            if (this.settings.getVisibilityMode().equals(VisibilityMode.VISIBLE))
-            {
-                icon = new ItemStack(Material.OAK_PLANKS);
-            }
-            else if (this.settings.getVisibilityMode().equals(VisibilityMode.HIDDEN))
-            {
-                icon = new ItemStack(Material.OAK_SLAB);
-            }
-            else
-            {
-                icon = new ItemStack(Material.OAK_BUTTON);
-            }
-
-            clickHandler = (panel, user, clickType, slot) -> {
-                if (clickType.isRightClick())
-                {
-                    this.settings.setVisibilityMode(
-                            Utils.getPreviousValue(VisibilityMode.values(),
-                                    this.settings.getVisibilityMode()));
-                }
-                else
-                {
-                    this.settings.setVisibilityMode(
-                            Utils.getNextValue(VisibilityMode.values(),
-                                    this.settings.getVisibilityMode()));
-                }
-
-                // Rebuild just this icon
-                panel.getInventory().setItem(slot,
-                        this.getSettingsButton(button).getItem());
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        default:
-            return new PanelItemBuilder().build();
-        }
-
-        return new PanelItemBuilder().
-                icon(icon).
-                name(name).
-                description(GuiUtils.stringSplit(description, this.settings.getLoreLineLength())).
-                glow(glow).
-                clickHandler(clickHandler).
-                build();
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Variables
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * This enum holds all settings buttons that must have been displayed in this panel.
-     */
-    private enum Button
-    {
-        RESET_CHALLENGES,
-        BROADCAST,
-        REMOVE_COMPLETED,
-        LORE_LENGTH,
-        LEVEL_LORE,
-        CHALLENGE_LORE,
-        FREE_AT_TOP,
-        GAMEMODE_GUI_VIEW_MODE,
-        GAMEMODE_GUI,
-        HISTORY,
-        PURGE_HISTORY,
-        STORE_MODE,
-        GLOW_COMPLETED,
-        LOCKED_LEVEL_ICON,
-        ENABLE_TITLE,
-        TITLE_SHOWTIME,
-
-        /**
-         * This allows to switch between different challenges visibility modes.
-         */
-        VISIBILITY_MODE
-    }
-
-
-    /**
-     * This allows faster access to challenges settings object.
-     */
-    private Settings settings;
-}

src/main/java/world/bentobox/challenges/panel/admin/EditSettingsPanel.java

@@ -0,0 +1,576 @@
+package world.bentobox.challenges.panel.admin;
+
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Consumer;
+
+import org.bukkit.Material;
+import org.bukkit.World;
+import org.bukkit.event.inventory.InventoryClickEvent;
+import org.bukkit.event.inventory.InventoryCloseEvent;
+import org.bukkit.inventory.ItemStack;
+
+import world.bentobox.bentobox.api.panels.PanelItem;
+import world.bentobox.bentobox.api.panels.PanelListener;
+import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
+import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
+import world.bentobox.bentobox.api.user.User;
+import world.bentobox.challenges.ChallengesAddon;
+import world.bentobox.challenges.config.Settings;
+import world.bentobox.challenges.config.SettingsUtils.GuiMode;
+import world.bentobox.challenges.config.SettingsUtils.VisibilityMode;
+import world.bentobox.challenges.panel.CommonPanel;
+import world.bentobox.challenges.panel.ConversationUtils;
+import world.bentobox.challenges.utils.Constants;
+import world.bentobox.challenges.utils.GuiUtils;
+import world.bentobox.challenges.utils.Utils;
+
+
+/**
+ * This Class creates GUI that allows to change Challenges Addon Settings via in-game
+ * menu.
+ */
+public class EditSettingsPanel extends CommonPanel
+{
+    // ---------------------------------------------------------------------
+    // Section: Constructors
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * @param addon Addon where panel operates.
+     * @param world World from which panel was created.
+     * @param user User who created panel.
+     * @param topLabel Command top label which creates panel (f.e. island or ai)
+     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
+     */
+    private EditSettingsPanel(ChallengesAddon addon,
+        User user,
+        World world,
+        String topLabel,
+        String permissionPrefix)
+    {
+        super(addon, user, world, topLabel, permissionPrefix);
+        this.settings = this.addon.getChallengesSettings();
+    }
+
+
+    /**
+     * @param parentGUI Parent GUI.
+     */
+    private EditSettingsPanel(CommonPanel parentGUI)
+    {
+        super(parentGUI);
+        this.settings = this.addon.getChallengesSettings();
+    }
+
+
+    /**
+     * Open the Challenges Admin GUI.
+     *
+     * @param addon the addon
+     * @param world the world
+     * @param user the user
+     * @param topLabel the top label
+     * @param permissionPrefix the permission prefix
+     */
+    public static void open(ChallengesAddon addon,
+        World world,
+        User user,
+        String topLabel,
+        String permissionPrefix)
+    {
+        new EditSettingsPanel(addon, user, world, topLabel, permissionPrefix).build();
+    }
+
+
+    /**
+     * Open the Challenges Admin GUI.
+     */
+    public static void open(CommonPanel parentGUI)
+    {
+        new EditSettingsPanel(parentGUI).build();
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Methods
+    // ---------------------------------------------------------------------
+
+
+    @Override
+    protected void build()
+    {
+        PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(
+            this.user.getTranslation(Constants.TITLE + "settings"));
+
+        GuiUtils.fillBorder(panelBuilder);
+
+        panelBuilder.item(10, this.getSettingsButton(Button.SHOW_TITLE));
+
+        if (this.settings.isShowCompletionTitle())
+        {
+            panelBuilder.item(19, this.getSettingsButton(Button.TITLE_SHOWTIME));
+        }
+
+        panelBuilder.item(28, this.getSettingsButton(Button.BROADCAST));
+
+        panelBuilder.item(11, this.getSettingsButton(Button.GLOW_COMPLETED));
+        panelBuilder.item(20, this.getSettingsButton(Button.REMOVE_COMPLETED));
+        panelBuilder.item(29, this.getSettingsButton(Button.VISIBILITY_MODE));
+
+        panelBuilder.item(21, this.getSettingsButton(Button.LOCKED_LEVEL_ICON));
+
+        panelBuilder.item(22, this.getSettingsButton(Button.GAMEMODE_GUI));
+
+        if (this.settings.isUseCommonGUI())
+        {
+            // This should be active only when single gui is enabled.
+            panelBuilder.item(31, this.getSettingsButton(Button.ACTIVE_WORLD_LIST));
+        }
+
+        panelBuilder.item(24, this.getSettingsButton(Button.STORE_HISTORY));
+
+        if (this.settings.isStoreHistory())
+        {
+            panelBuilder.item(33, this.getSettingsButton(Button.PURGE_HISTORY));
+        }
+
+        panelBuilder.item(25, this.getSettingsButton(Button.RESET_ON_NEW));
+        panelBuilder.item(34, this.getSettingsButton(Button.DATA_PER_ISLAND));
+
+        // Return Button
+        panelBuilder.item(44, this.returnButton);
+        panelBuilder.listener(new IconChanger());
+        panelBuilder.build();
+    }
+
+
+    private PanelItem getSettingsButton(Button button)
+    {
+        final String reference = Constants.BUTTON + button.name().toLowerCase() + ".";
+
+        final String name = this.user.getTranslation(reference + "name");
+        final List<String> description = new ArrayList<>(3);
+        description.add(this.user.getTranslation(reference + "description"));
+
+        ItemStack icon;
+        boolean glow;
+        PanelItem.ClickHandler clickHandler;
+
+        switch (button)
+        {
+            case RESET_ON_NEW -> {
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.isResetChallenges() ? "enabled" : "disabled")));
+
+                icon = new ItemStack(Material.LAVA_BUCKET);
+                clickHandler = (panel, user1, clickType, i) -> {
+                    this.settings.setResetChallenges(!this.settings.isResetChallenges());
+                    panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
+                    this.addon.saveSettings();
+                    return true;
+                };
+                glow = this.settings.isResetChallenges();
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-toggle"));
+            }
+            case BROADCAST -> {
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.isBroadcastMessages() ? "enabled" : "disabled")));
+
+                icon = new ItemStack(Material.JUKEBOX);
+                clickHandler = (panel, user1, clickType, i) -> {
+                    this.settings.setBroadcastMessages(!this.settings.isBroadcastMessages());
+                    panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
+                    this.addon.saveSettings();
+                    return true;
+                };
+                glow = this.settings.isBroadcastMessages();
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-toggle"));
+            }
+            case REMOVE_COMPLETED -> {
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.isRemoveCompleteOneTimeChallenges() ? "enabled" : "disabled")));
+
+                icon = new ItemStack(Material.MAGMA_BLOCK);
+                clickHandler = (panel, user1, clickType, i) -> {
+                    this.settings.setRemoveCompleteOneTimeChallenges(!this.settings.isRemoveCompleteOneTimeChallenges());
+                    panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
+                    this.addon.saveSettings();
+                    return true;
+                };
+                glow = this.settings.isRemoveCompleteOneTimeChallenges();
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-toggle"));
+            }
+            case ACTIVE_WORLD_LIST -> {
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.getUserGuiMode().equals(GuiMode.GAMEMODE_LIST) ?
+                        "disabled" : "enabled")));
+
+                icon = new ItemStack(Material.STONE_BUTTON);
+                clickHandler = (panel, user1, clickType, i) -> {
+                    if (this.settings.getUserGuiMode().equals(GuiMode.GAMEMODE_LIST))
+                    {
+                        this.settings.setUserGuiMode(GuiMode.CURRENT_WORLD);
+                    }
+                    else
+                    {
+                        this.settings.setUserGuiMode(GuiMode.GAMEMODE_LIST);
+                    }
+
+                    this.addon.saveSettings();
+                    panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
+                    return true;
+                };
+                glow = this.settings.getUserGuiMode().equals(GuiMode.GAMEMODE_LIST);
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+            }
+            case GAMEMODE_GUI -> {
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.isUseCommonGUI() ? "enabled" : "disabled")));
+
+                icon = new ItemStack(Material.BLACK_STAINED_GLASS_PANE);
+                clickHandler = (panel, user1, clickType, i) -> {
+                    this.settings.setUseCommonGUI(!this.settings.isUseCommonGUI());
+                    // Need to rebuild more icons
+                    this.build();
+                    this.addon.saveSettings();
+                    return true;
+                };
+                glow = this.settings.isUseCommonGUI();
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-toggle"));
+            }
+            case STORE_HISTORY -> {
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.isStoreHistory() ? "enabled" : "disabled")));
+
+                icon = new ItemStack(Material.WRITTEN_BOOK);
+                clickHandler = (panel, user1, clickType, i) -> {
+                    this.settings.setStoreHistory(!this.settings.isStoreHistory());
+                    panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
+                    this.addon.saveSettings();
+                    return true;
+                };
+                glow = this.settings.isStoreHistory();
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-toggle"));
+            }
+            case PURGE_HISTORY -> {
+                description.add(this.user.getTranslation(reference + "value",
+                    Constants.NUMBER, String.valueOf(this.settings.getLifeSpan())));
+
+                icon = new ItemStack(Material.FLINT_AND_STEEL, Math.max(1, this.settings.getLifeSpan()));
+                clickHandler = (panel, user, clickType, i) -> {
+                    Consumer<Number> numberConsumer = number -> {
+                        if (number != null)
+                        {
+                            this.settings.setLifeSpan(number.intValue());
+                            this.addon.saveSettings();
+                        }
+
+                        // reopen panel
+                        this.build();
+                    };
+
+                    ConversationUtils.createNumericInput(numberConsumer,
+                        this.user,
+                        this.user.getTranslation(Constants.CONVERSATIONS + "input-number"),
+                        0,
+                        2000);
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+            }
+            case DATA_PER_ISLAND -> {
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.isStoreAsIslandData() ? "enabled" : "disabled")));
+
+                icon = new ItemStack(Material.GRASS_BLOCK);
+                clickHandler = (panel, user1, clickType, i) -> {
+                    this.settings.setStoreAsIslandData(!this.settings.isStoreAsIslandData());
+                    // TODO: Migration
+                    panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
+                    this.addon.saveSettings();
+                    return true;
+                };
+                glow = this.settings.isStoreAsIslandData();
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-toggle"));
+            }
+            case GLOW_COMPLETED -> {
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.isAddCompletedGlow() ? "enabled" : "disabled")));
+
+                icon = new ItemStack(Material.GLOWSTONE);
+                clickHandler = (panel, user1, clickType, i) -> {
+                    this.settings.setAddCompletedGlow(!this.settings.isAddCompletedGlow());
+                    panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
+                    this.addon.saveSettings();
+                    return true;
+                };
+                glow = this.settings.isAddCompletedGlow();
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-toggle"));
+            }
+            case LOCKED_LEVEL_ICON -> {
+                icon = this.settings.getLockedLevelIcon();
+
+                clickHandler = (panel, user, clickType, i) ->
+                {
+                    if (this.selectedButton != null)
+                    {
+                        this.selectedButton = null;
+                    }
+                    else
+                    {
+                        this.selectedButton = button;
+                    }
+
+                    panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
+                    return true;
+                };
+
+                if (this.selectedButton != button)
+                {
+                    description.add("");
+                    description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+                }
+                else
+                {
+                    description.add("");
+                    description.add(this.user.getTranslation(Constants.TIPS + "click-on-item"));
+                }
+
+                glow = this.selectedButton == button;
+            }
+            case SHOW_TITLE -> {
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.isShowCompletionTitle() ? "enabled" : "disabled")));
+
+                icon = new ItemStack(Material.OAK_SIGN);
+                clickHandler = (panel, user1, clickType, i) -> {
+                    this.settings.setShowCompletionTitle(!this.settings.isShowCompletionTitle());
+                    panel.getInventory().setItem(i, this.getSettingsButton(button).getItem());
+                    this.addon.saveSettings();
+                    return true;
+                };
+                glow = this.settings.isShowCompletionTitle();
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-toggle"));
+            }
+            case TITLE_SHOWTIME -> {
+                description.add(this.user.getTranslation(reference + "value",
+                    Constants.NUMBER, String.valueOf(this.settings.getTitleShowtime())));
+
+                icon = new ItemStack(Material.CLOCK, Math.max(1, this.settings.getTitleShowtime()));
+                clickHandler = (panel, user, clickType, i) -> {
+                    Consumer<Number> numberConsumer = number -> {
+                        if (number != null)
+                        {
+                            this.settings.setTitleShowtime(number.intValue());
+                            this.addon.saveSettings();
+                        }
+
+                        // reopen panel
+                        this.build();
+                    };
+
+                    ConversationUtils.createNumericInput(numberConsumer,
+                        this.user,
+                        this.user.getTranslation(Constants.CONVERSATIONS + "input-number"),
+                        0,
+                        2000);
+
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "click-to-change"));
+            }
+            case VISIBILITY_MODE -> {
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.getVisibilityMode().equals(VisibilityMode.VISIBLE) ? "enabled" : "disabled")) +
+                    this.user.getTranslation(reference + "visible"));
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.getVisibilityMode().equals(VisibilityMode.HIDDEN) ? "enabled" : "disabled")) +
+                    this.user.getTranslation(reference + "hidden"));
+                description.add(this.user.getTranslation(reference +
+                    (this.settings.getVisibilityMode().equals(VisibilityMode.TOGGLEABLE) ? "enabled" : "disabled")) +
+                    this.user.getTranslation(reference + "toggleable"));
+
+                if (this.settings.getVisibilityMode().equals(VisibilityMode.VISIBLE))
+                {
+                    icon = new ItemStack(Material.OAK_PLANKS);
+                }
+                else if (this.settings.getVisibilityMode().equals(VisibilityMode.HIDDEN))
+                {
+                    icon = new ItemStack(Material.OAK_SLAB);
+                }
+                else
+                {
+                    icon = new ItemStack(Material.OAK_BUTTON);
+                }
+
+                clickHandler = (panel, user, clickType, slot) -> {
+                    if (clickType.isRightClick())
+                    {
+                        this.settings.setVisibilityMode(Utils.getPreviousValue(VisibilityMode.values(),
+                            this.settings.getVisibilityMode()));
+                    }
+                    else
+                    {
+                        this.settings.setVisibilityMode(Utils.getNextValue(VisibilityMode.values(),
+                            this.settings.getVisibilityMode()));
+                    }
+
+                    // Rebuild just this icon
+                    panel.getInventory().setItem(slot, this.getSettingsButton(button).getItem());
+                    this.addon.saveSettings();
+                    return true;
+                };
+                glow = false;
+
+                description.add("");
+                description.add(this.user.getTranslation(Constants.TIPS + "left-click-to-cycle"));
+                description.add(this.user.getTranslation(Constants.TIPS + "right-click-to-cycle"));
+            }
+            default -> {
+                icon = new ItemStack(Material.PAPER);
+                clickHandler = null;
+                glow = false;
+            }
+        }
+
+        return new PanelItemBuilder().
+            icon(icon).
+            name(name).
+            description(description).
+            glow(glow).
+            clickHandler(clickHandler).
+            build();
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Classes
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * This class allows changing icon for Generator Tier
+     */
+    private class IconChanger implements PanelListener
+    {
+        /**
+         * Process inventory click. If generator icon is selected and user clicks on item in his inventory, then change
+         * icon to the item from inventory.
+         *
+         * @param user the user
+         * @param event the event
+         */
+        @Override
+        public void onInventoryClick(User user, InventoryClickEvent event)
+        {
+            // Handle icon changing
+            if (EditSettingsPanel.this.selectedButton != null &&
+                event.getCurrentItem() != null &&
+                !event.getCurrentItem().getType().equals(Material.AIR) &&
+                event.getRawSlot() > 44)
+            {
+                // set material and amount only. Other data should be removed.
+
+                if (EditSettingsPanel.this.selectedButton == Button.LOCKED_LEVEL_ICON)
+                {
+                    EditSettingsPanel.this.settings.setLockedLevelIcon(event.getCurrentItem().clone());
+                    EditSettingsPanel.this.addon.saveSettings();
+
+                    // Deselect icon
+                    EditSettingsPanel.this.selectedButton = null;
+                    EditSettingsPanel.this.build();
+                }
+            }
+        }
+
+
+        /**
+         * On inventory close.
+         *
+         * @param event the event
+         */
+        @Override
+        public void onInventoryClose(InventoryCloseEvent event)
+        {
+            // Do nothing
+        }
+
+
+        /**
+         * Setup current listener.
+         */
+        @Override
+        public void setup()
+        {
+            // Do nothing
+        }
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Variables
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * This enum holds all settings buttons that must have been displayed in this panel.
+     */
+    private enum Button
+    {
+        RESET_ON_NEW,
+        BROADCAST,
+        REMOVE_COMPLETED,
+        ACTIVE_WORLD_LIST,
+        GAMEMODE_GUI,
+        STORE_HISTORY,
+        PURGE_HISTORY,
+        DATA_PER_ISLAND,
+        GLOW_COMPLETED,
+        LOCKED_LEVEL_ICON,
+        SHOW_TITLE,
+        TITLE_SHOWTIME,
+        /**
+         * This allows to switch between different challenges visibility modes.
+         */
+        VISIBILITY_MODE
+    }
+
+
+    /**
+     * This allows faster access to challenges settings object.
+     */
+    private final Settings settings;
+
+    /**
+     * Allows changing locked level icon.
+     */
+    private Button selectedButton;
+}

src/main/java/world/bentobox/challenges/panel/admin/ListChallengesPanel.java

@@ -1,9 +1,8 @@
 package world.bentobox.challenges.panel.admin;
 
 
-import java.util.List;
+import java.util.function.Consumer;
 
-import org.bukkit.ChatColor;
 import org.bukkit.Material;
 import org.bukkit.World;
 
@@ -11,18 +10,22 @@ import world.bentobox.bentobox.api.panels.PanelItem;
 import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
 import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
 import world.bentobox.bentobox.api.user.User;
+import world.bentobox.bentobox.util.Util;
 import world.bentobox.challenges.ChallengesAddon;
 import world.bentobox.challenges.database.object.Challenge;
-import world.bentobox.challenges.panel.CommonGUI;
-import world.bentobox.challenges.panel.util.ConfirmationGUI;
+import world.bentobox.challenges.panel.CommonPagedPanel;
+import world.bentobox.challenges.panel.CommonPanel;
+import world.bentobox.challenges.panel.ConversationUtils;
+import world.bentobox.challenges.utils.Constants;
 import world.bentobox.challenges.utils.GuiUtils;
+import world.bentobox.challenges.utils.Utils;
 
 
 /**
  * This class contains all necessary elements to create GUI that lists all challenges.
  * It allows to edit them or remove, depending on given input mode.
  */
-public class ListChallengesGUI extends CommonGUI
+public class ListChallengesPanel extends CommonPagedPanel
 {
     // ---------------------------------------------------------------------
     // Section: Constructor
@@ -37,38 +40,57 @@ public class ListChallengesGUI extends CommonGUI
      * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
      * @param mode - mode that indicate what should do icon clicking.
      */
-    public ListChallengesGUI(ChallengesAddon addon,
+    private ListChallengesPanel(ChallengesAddon addon,
             World world,
             User user,
             Mode mode,
             String topLabel,
             String permissionPrefix)
     {
-        this(addon, world, user, mode, topLabel, permissionPrefix, null);
+        super(addon, user, world, topLabel, permissionPrefix);
+        this.currentMode = mode;
     }
 
 
     /**
-     * @param addon Addon where panel operates.
-     * @param world World from which panel was created.
-     * @param user User who created panel.
-     * @param topLabel Command top label which creates panel (f.e. island or ai)
-     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
      * @param mode - mode that indicate what should do icon clicking.
      */
-    public ListChallengesGUI(ChallengesAddon addon,
-            World world,
-            User user,
-            Mode mode,
-            String topLabel,
-            String permissionPrefix,
-            CommonGUI parentGUI)
+    private ListChallengesPanel(CommonPanel parentGUI, Mode mode)
     {
-        super(addon, world, user, topLabel, permissionPrefix, parentGUI);
+        super(parentGUI);
         this.currentMode = mode;
     }
 
 
+    /**
+     * Open the Challenges Admin GUI.
+     *
+     * @param addon the addon
+     * @param world the world
+     * @param user the user
+     * @param topLabel the top label
+     * @param permissionPrefix the permission prefix
+     */
+    public static void open(ChallengesAddon addon,
+        World world,
+        User user,
+        String topLabel,
+        String permissionPrefix,
+        Mode mode)
+    {
+        new ListChallengesPanel(addon, world, user, mode, topLabel, permissionPrefix).build();
+    }
+
+
+    /**
+     * Open the Challenges Admin GUI.
+     */
+    public static void open(CommonPanel parentGUI, Mode mode)
+    {
+        new ListChallengesPanel(parentGUI, mode).build();
+    }
+
+
     // ---------------------------------------------------------------------
     // Section: Methods
     // ---------------------------------------------------------------------
@@ -78,10 +100,10 @@ public class ListChallengesGUI extends CommonGUI
      * {@inheritDoc}
      */
     @Override
-    public void build()
+    protected void build()
     {
         PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(
-                this.user.getTranslation("challenges.gui.title.admin.choose-challenge-title"));
+            this.user.getTranslation(Constants.TITLE + "choose-challenge"));
 
         if (this.currentMode.equals(Mode.DELETE))
         {
@@ -92,42 +114,9 @@ public class ListChallengesGUI extends CommonGUI
             GuiUtils.fillBorder(panelBuilder);
         }
 
-        List<Challenge> challengeList = this.addon.getChallengesManager().getAllChallenges(this.world);
-
-        final int MAX_ELEMENTS = 21;
-
-        if (this.pageIndex < 0)
-        {
-            this.pageIndex = challengeList.size() / MAX_ELEMENTS;
-        }
-        else if (this.pageIndex > (challengeList.size() / MAX_ELEMENTS))
-        {
-            this.pageIndex = 0;
-        }
-
-        int challengeIndex = MAX_ELEMENTS * this.pageIndex;
-
-        // I want first row to be only for navigation and return button.
-        int index = 10;
-
-        while (challengeIndex < ((this.pageIndex + 1) * MAX_ELEMENTS) &&
-                challengeIndex < challengeList.size() &&
-                index < 36)
-        {
-            if (!panelBuilder.slotOccupied(index))
-            {
-                panelBuilder.item(index, this.createChallengeIcon(challengeList.get(challengeIndex++)));
-            }
-
-            index++;
-        }
-
-        // Navigation buttons only if necessary
-        if (challengeList.size() > MAX_ELEMENTS)
-        {
-            panelBuilder.item(18, this.getButton(CommonButtons.PREVIOUS));
-            panelBuilder.item(26, this.getButton(CommonButtons.NEXT));
-        }
+        this.populateElements(panelBuilder,
+            this.addon.getChallengesManager().getAllChallenges(this.world),
+            o -> this.createChallengeIcon((Challenge) o));
 
         panelBuilder.item(44, this.returnButton);
 
@@ -143,36 +132,46 @@ public class ListChallengesGUI extends CommonGUI
     private PanelItem createChallengeIcon(Challenge challenge)
     {
         PanelItemBuilder itemBuilder = new PanelItemBuilder().
-                name(ChatColor.translateAlternateColorCodes('&', challenge.getFriendlyName())).
-                description(GuiUtils.stringSplit(this.generateChallengeDescription(challenge, this.user.getPlayer()),
-                        this.addon.getChallengesSettings().getLoreLineLength())).
-                icon(challenge.getIcon()).
-                glow(challenge.isDeployed());
+            name(Util.translateColorCodes(challenge.getFriendlyName())).
+            description(this.generateChallengeDescription(challenge, null)).
+            icon(challenge.getIcon()).
+            glow(!challenge.isDeployed());
 
         if (this.currentMode.equals(Mode.EDIT))
         {
+            itemBuilder.description("");
+            itemBuilder.description(this.user.getTranslation(Constants.TIPS + "click-to-edit"));
+
             itemBuilder.clickHandler((panel, user1, clickType, i) -> {
-                new EditChallengeGUI(this.addon,
-                        this.world,
-                        this.user,
-                        challenge,
-                        this.topLabel,
-                        this.permissionPrefix,
-                        this).build();
+                EditChallengePanel.open(this, challenge);
                 return true;
             });
         }
         else if (this.currentMode.equals(Mode.DELETE))
         {
+            itemBuilder.description("");
+            itemBuilder.description(this.user.getTranslation(Constants.TIPS + "click-to-remove"));
+
             itemBuilder.clickHandler((panel, user1, clickType, i) -> {
-                new ConfirmationGUI(this.user, value -> {
+                Consumer<Boolean> consumer = value -> {
                     if (value)
                     {
                         this.addon.getChallengesManager().deleteChallenge(challenge);
                     }
 
                     this.build();
-                });
+                };
+
+                // Create conversation that gets user acceptance to delete generator data.
+                ConversationUtils.createConfirmation(
+                    consumer,
+                    this.user,
+                    this.user.getTranslation(Constants.CONVERSATIONS + "confirm-challenge-deletion",
+                        Constants.GAMEMODE, Utils.getGameMode(this.world),
+                        Constants.CHALLENGE, challenge.getFriendlyName()),
+                    this.user.getTranslation(Constants.CONVERSATIONS + "challenge-removed",
+                        Constants.GAMEMODE, Utils.getGameMode(this.world),
+                        Constants.CHALLENGE, challenge.getFriendlyName()));
                 return true;
             });
         }
@@ -203,5 +202,5 @@ public class ListChallengesGUI extends CommonGUI
     /**
      * Current mode in which icons will act.
      */
-    private Mode currentMode;
+    private final Mode currentMode;
 }

src/main/java/world/bentobox/challenges/panel/admin/ListLevelsPanel.java

@@ -1,28 +1,31 @@
 package world.bentobox.challenges.panel.admin;
 
 
-import java.util.List;
-
-import org.bukkit.ChatColor;
 import org.bukkit.Material;
 import org.bukkit.World;
 
+import java.util.function.Consumer;
+
 import world.bentobox.bentobox.api.panels.PanelItem;
 import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
 import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
 import world.bentobox.bentobox.api.user.User;
+import world.bentobox.bentobox.util.Util;
 import world.bentobox.challenges.ChallengesAddon;
 import world.bentobox.challenges.database.object.ChallengeLevel;
-import world.bentobox.challenges.panel.CommonGUI;
-import world.bentobox.challenges.panel.util.ConfirmationGUI;
+import world.bentobox.challenges.panel.CommonPagedPanel;
+import world.bentobox.challenges.panel.CommonPanel;
+import world.bentobox.challenges.panel.ConversationUtils;
+import world.bentobox.challenges.utils.Constants;
 import world.bentobox.challenges.utils.GuiUtils;
+import world.bentobox.challenges.utils.Utils;
 
 
 /**
  * This class creates GUI that lists all Levels. Clicking on Level icon will be processed
  * by input mode.
  */
-public class ListLevelsGUI extends CommonGUI
+public class ListLevelsPanel extends CommonPagedPanel
 {
     // ---------------------------------------------------------------------
     // Section: Constructor
@@ -37,38 +40,57 @@ public class ListLevelsGUI extends CommonGUI
      * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
      * @param mode - mode that indicate what should do icon clicking.
      */
-    public ListLevelsGUI(ChallengesAddon addon,
+    private ListLevelsPanel(ChallengesAddon addon,
             World world,
             User user,
             Mode mode,
             String topLabel,
             String permissionPrefix)
     {
-        this(addon, world, user, mode, topLabel, permissionPrefix, null);
+        super(addon, user, world, topLabel, permissionPrefix);
+        this.currentMode = mode;
     }
 
 
     /**
-     * @param addon Addon where panel operates.
-     * @param world World from which panel was created.
-     * @param user User who created panel.
-     * @param topLabel Command top label which creates panel (f.e. island or ai)
-     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
      * @param mode - mode that indicate what should do icon clicking.
      */
-    public ListLevelsGUI(ChallengesAddon addon,
-            World world,
-            User user,
-            Mode mode,
-            String topLabel,
-            String permissionPrefix,
-            CommonGUI parentGUI)
+    private ListLevelsPanel(CommonPanel parentGUI, Mode mode)
     {
-        super(addon, world, user, topLabel, permissionPrefix, parentGUI);
+        super(parentGUI);
         this.currentMode = mode;
     }
 
 
+    /**
+     * Open the Challenges Admin GUI.
+     *
+     * @param addon the addon
+     * @param world the world
+     * @param user the user
+     * @param topLabel the top label
+     * @param permissionPrefix the permission prefix
+     */
+    public static void open(ChallengesAddon addon,
+        World world,
+        User user,
+        String topLabel,
+        String permissionPrefix,
+        Mode mode)
+    {
+        new ListLevelsPanel(addon, world, user, mode, topLabel, permissionPrefix).build();
+    }
+
+
+    /**
+     * Open the Challenges Admin GUI.
+     */
+    public static void open(CommonPanel parentGUI, Mode mode)
+    {
+        new ListLevelsPanel(parentGUI, mode).build();
+    }
+
+
     // ---------------------------------------------------------------------
     // Section: Methods
     // ---------------------------------------------------------------------
@@ -78,10 +100,10 @@ public class ListLevelsGUI extends CommonGUI
      * {@inheritDoc}
      */
     @Override
-    public void build()
+    protected void build()
     {
         PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(
-                this.user.getTranslation("challenges.gui.title.admin.choose-level-title"));
+            this.user.getTranslation(Constants.TITLE + "choose-level"));
 
         if (this.currentMode.equals(Mode.DELETE))
         {
@@ -92,42 +114,9 @@ public class ListLevelsGUI extends CommonGUI
             GuiUtils.fillBorder(panelBuilder);
         }
 
-        List<ChallengeLevel> levelList = this.addon.getChallengesManager().getLevels(this.world);
-
-        final int MAX_ELEMENTS = 21;
-
-        if (this.pageIndex < 0)
-        {
-            this.pageIndex = levelList.size() / MAX_ELEMENTS;
-        }
-        else if (this.pageIndex > (levelList.size() / MAX_ELEMENTS))
-        {
-            this.pageIndex = 0;
-        }
-
-        int levelIndex = MAX_ELEMENTS * this.pageIndex;
-
-        // I want first row to be only for navigation and return button.
-        int index = 10;
-
-        while (levelIndex < ((this.pageIndex + 1) * MAX_ELEMENTS) &&
-                levelIndex < levelList.size() &&
-                index < 36)
-        {
-            if (!panelBuilder.slotOccupied(index))
-            {
-                panelBuilder.item(index, this.createLevelIcon(levelList.get(levelIndex++)));
-            }
-
-            index++;
-        }
-
-        // Navigation buttons only if necessary
-        if (levelList.size() > MAX_ELEMENTS)
-        {
-            panelBuilder.item(18, this.getButton(CommonButtons.PREVIOUS));
-            panelBuilder.item(26, this.getButton(CommonButtons.NEXT));
-        }
+        this.populateElements(panelBuilder,
+            this.addon.getChallengesManager().getLevels(this.world),
+            o -> this.createLevelIcon((ChallengeLevel) o));
 
         panelBuilder.item(44, this.returnButton);
 
@@ -143,38 +132,45 @@ public class ListLevelsGUI extends CommonGUI
     private PanelItem createLevelIcon(ChallengeLevel challengeLevel)
     {
         PanelItemBuilder itemBuilder = new PanelItemBuilder().
-                name(ChatColor.translateAlternateColorCodes('&', challengeLevel.getFriendlyName())).
-                description(GuiUtils.stringSplit(
-                        this.generateLevelDescription(challengeLevel, this.user.getPlayer()),
-                        this.addon.getChallengesSettings().getLoreLineLength())).
-                icon(challengeLevel.getIcon()).
-                glow(false);
+            name(Util.translateColorCodes(challengeLevel.getFriendlyName())).
+            description(this.generateLevelDescription(challengeLevel)).
+            icon(challengeLevel.getIcon());
 
         if (this.currentMode.equals(Mode.EDIT))
         {
+            itemBuilder.description("");
+            itemBuilder.description(this.user.getTranslation(Constants.TIPS + "click-to-edit"));
+
             itemBuilder.clickHandler((panel, user1, clickType, i) -> {
-                new EditLevelGUI(this.addon,
-                        this.world,
-                        this.user,
-                        challengeLevel,
-                        this.topLabel,
-                        this.permissionPrefix,
-                        this).build();
+                EditLevelPanel.open(this, challengeLevel);
                 return true;
             });
         }
         else if (this.currentMode.equals(Mode.DELETE))
         {
+            itemBuilder.description("");
+            itemBuilder.description(this.user.getTranslation(Constants.TIPS + "click-to-remove"));
+
             itemBuilder.clickHandler((panel, user1, clickType, i) -> {
-                new ConfirmationGUI(this.user, value -> {
+                Consumer<Boolean> consumer = value -> {
                     if (value)
                     {
-                        this.addon.getChallengesManager().
-                        deleteChallengeLevel(challengeLevel);
+                        this.addon.getChallengesManager().deleteChallengeLevel(challengeLevel);
                     }
 
                     this.build();
-                });
+                };
+
+                // Create conversation that gets user acceptance to delete generator data.
+                ConversationUtils.createConfirmation(
+                    consumer,
+                    this.user,
+                    this.user.getTranslation(Constants.CONVERSATIONS + "confirm-level-deletion",
+                        Constants.GAMEMODE, Utils.getGameMode(this.world),
+                        Constants.LEVEL, challengeLevel.getFriendlyName()),
+                    this.user.getTranslation(Constants.CONVERSATIONS + "level-removed",
+                        Constants.GAMEMODE, Utils.getGameMode(this.world),
+                        Constants.LEVEL, challengeLevel.getFriendlyName()));
                 return true;
             });
         }
@@ -202,8 +198,9 @@ public class ListLevelsGUI extends CommonGUI
     // Section: Variables
     // ---------------------------------------------------------------------
 
+
     /**
      * Current mode in which icons will act.
      */
-    private Mode currentMode;
+    private final Mode currentMode;
 }

src/main/java/world/bentobox/challenges/panel/admin/ListLibraryPanel.java

@@ -7,15 +7,21 @@ import java.util.List;
 import org.bukkit.ChatColor;
 import org.bukkit.Material;
 import org.bukkit.World;
+import org.bukkit.event.inventory.InventoryClickEvent;
+import org.bukkit.event.inventory.InventoryCloseEvent;
 import org.bukkit.scheduler.BukkitTask;
 
 import world.bentobox.bentobox.api.panels.PanelItem;
+import world.bentobox.bentobox.api.panels.PanelListener;
 import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
 import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
 import world.bentobox.bentobox.api.user.User;
 import world.bentobox.challenges.ChallengesAddon;
-import world.bentobox.challenges.panel.CommonGUI;
+import world.bentobox.challenges.panel.CommonPagedPanel;
+import world.bentobox.challenges.panel.CommonPanel;
+import world.bentobox.challenges.utils.Constants;
 import world.bentobox.challenges.utils.GuiUtils;
+import world.bentobox.challenges.utils.Utils;
 import world.bentobox.challenges.web.object.LibraryEntry;
 
 
@@ -23,7 +29,7 @@ import world.bentobox.challenges.web.object.LibraryEntry;
  * This class contains all necessary elements to create GUI that lists all challenges.
  * It allows to edit them or remove, depending on given input mode.
  */
-public class ListLibraryGUI extends CommonGUI
+public class ListLibraryPanel extends CommonPagedPanel
 {
     // ---------------------------------------------------------------------
     // Section: Constructor
@@ -32,7 +38,7 @@ public class ListLibraryGUI extends CommonGUI
     /**
      * @param parentGUI ParentGUI object.
      */
-    public ListLibraryGUI(CommonGUI parentGUI)
+    private ListLibraryPanel(CommonPanel parentGUI)
     {
         super(parentGUI);
     }
@@ -45,23 +51,43 @@ public class ListLibraryGUI extends CommonGUI
      * @param topLabel Command top label which creates panel (f.e. island or ai)
      * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
      */
-    public ListLibraryGUI(ChallengesAddon addon,
+    private ListLibraryPanel(ChallengesAddon addon,
             World world,
             User user,
             String topLabel,
             String permissionPrefix)
     {
-        super(addon, world, user, topLabel, permissionPrefix, null);
+        super(addon, user, world, topLabel, permissionPrefix);
     }
 
 
+    /**
+     * Open the Challenges Admin GUI.
+     *
+     * @param addon the addon
+     * @param world the world
+     * @param user the user
+     * @param topLabel the top label
+     * @param permissionPrefix the permission prefix
+     */
+    public static void open(ChallengesAddon addon,
+        World world,
+        User user,
+        String topLabel,
+        String permissionPrefix)
+    {
+        new ListLibraryPanel(addon, world, user, topLabel, permissionPrefix).build();
+    }
+
+
+
     /**
      * This static method allows to easier open Library GUI.
      * @param parentGui ParentGUI object.
      */
-    public static void open(CommonGUI parentGui)
+    public static void open(CommonPanel parentGui)
     {
-        new ListLibraryGUI(parentGui).build();
+        new ListLibraryPanel(parentGui).build();
     }
 
 
@@ -74,52 +100,21 @@ public class ListLibraryGUI extends CommonGUI
      * {@inheritDoc}
      */
     @Override
-    public void build()
+    protected void build()
     {
         PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(
-            this.user.getTranslation("challenges.gui.title.admin.library-title"));
+            this.user.getTranslation(Constants.TITLE + "library"));
 
         GuiUtils.fillBorder(panelBuilder);
 
-        List<LibraryEntry> libraryEntries = this.addon.getWebManager().getLibraryEntries();
-
-        final int MAX_ELEMENTS = 21;
-
-        if (this.pageIndex < 0)
-        {
-            this.pageIndex = libraryEntries.size() / MAX_ELEMENTS;
-        }
-        else if (this.pageIndex > (libraryEntries.size() / MAX_ELEMENTS))
-        {
-            this.pageIndex = 0;
-        }
-
-        int entryIndex = MAX_ELEMENTS * this.pageIndex;
-
-        // I want first row to be only for navigation and return button.
-        int index = 10;
-
-        while (entryIndex < ((this.pageIndex + 1) * MAX_ELEMENTS) &&
-                entryIndex < libraryEntries.size() &&
-                index < 36)
-        {
-            if (!panelBuilder.slotOccupied(index))
-            {
-                panelBuilder.item(index, this.createEntryIcon(libraryEntries.get(entryIndex++)));
-            }
-
-            index++;
-        }
-
-        // Navigation buttons only if necessary
-        if (libraryEntries.size() > MAX_ELEMENTS)
-        {
-            panelBuilder.item(18, this.getButton(CommonButtons.PREVIOUS));
-            panelBuilder.item(26, this.getButton(CommonButtons.NEXT));
-        }
+        this.populateElements(panelBuilder,
+            this.addon.getWebManager().getLibraryEntries(),
+            o -> this.createEntryIcon((LibraryEntry) o));
 
         panelBuilder.item(4, this.createDownloadNow());
-        panelBuilder.item(44, this.createReturnButton());
+        panelBuilder.item(44, this.returnButton);
+
+        panelBuilder.listener(new DownloadCanceller());
 
         panelBuilder.build();
     }
@@ -131,17 +126,20 @@ public class ListLibraryGUI extends CommonGUI
      */
     private PanelItem createDownloadNow()
     {
-        List<String> description = new ArrayList<>(2);
-        description.add(this.user.getTranslation("challenges.gui.descriptions.admin.download"));
-        description.add(this.user.getTranslation("challenges.gui.descriptions.current-value",
-            "[value]",
-            this.clearCache ?
-                this.user.getTranslation("challenges.gui.descriptions.enabled") :
-                this.user.getTranslation("challenges.gui.descriptions.disabled")));
+        final String reference = Constants.BUTTON + "download.";
+
+        final List<String> description = new ArrayList<>(3);
+        description.add(this.user.getTranslation(reference + "description"));
+        description.add(this.user.getTranslation(reference +
+            (this.clearCache ? "enabled" : "disabled")));
+
+        description.add("");
+        description.add(this.user.getTranslation(Constants.TIPS + "left-click-to-download"));
+        description.add(this.user.getTranslation(Constants.TIPS + "right-click-to-toggle"));
 
         PanelItemBuilder itemBuilder = new PanelItemBuilder().
-            name(this.user.getTranslation("challenges.gui.buttons.admin.download")).
-            description(GuiUtils.stringSplit(description, this.addon.getChallengesSettings().getLoreLineLength())).
+            name(this.user.getTranslation(reference + "name")).
+            description(description).
             icon(Material.HOPPER).
             glow(this.clearCache);
 
@@ -176,33 +174,6 @@ public class ListLibraryGUI extends CommonGUI
     }
 
 
-    /**
-     * This creates return button, that allows to exist or return to parent gui,
-     * @return PanelItem for return button.
-     */
-    private PanelItem createReturnButton()
-    {
-        return new PanelItemBuilder().
-            name(this.user.getTranslation("challenges.gui.buttons.return")).
-            icon(Material.OAK_DOOR).
-            clickHandler((panel, user1, clickType, i) -> {
-                if (this.updateTask != null)
-                {
-                    this.updateTask.cancel();
-                }
-
-                if (this.parentGUI == null)
-                {
-                    this.user.closeInventory();
-                    return true;
-                }
-
-                this.parentGUI.build();
-                return true;
-            }).build();
-    }
-
-
     /**
      * This method creates button for given library entry.
      * @param libraryEntry LibraryEntry which button must be created.
@@ -211,10 +182,12 @@ public class ListLibraryGUI extends CommonGUI
     private PanelItem createEntryIcon(LibraryEntry libraryEntry)
     {
         PanelItemBuilder itemBuilder = new PanelItemBuilder().
-                name(ChatColor.translateAlternateColorCodes('&', libraryEntry.getName())).
-                description(this.generateEntryDescription(libraryEntry)).
-                icon(libraryEntry.getIcon()).
-                glow(false);
+            name(ChatColor.translateAlternateColorCodes('&', libraryEntry.getName())).
+            description(this.generateEntryDescription(libraryEntry)).
+            description("").
+            description(this.user.getTranslation(Constants.TIPS + "click-to-install")).
+            icon(libraryEntry.getIcon()).
+            glow(false);
 
         itemBuilder.clickHandler((panel, user1, clickType, i) -> {
 
@@ -222,7 +195,8 @@ public class ListLibraryGUI extends CommonGUI
             {
                 this.blockedForDownland = true;
 
-                this.user.sendMessage("challenges.messages.admin.start-downloading");
+                Utils.sendMessage(this.user,
+                    this.user.getTranslation(Constants.CONVERSATIONS + "start-downloading"));
 
                 // Run download task after 5 ticks.
                 this.addon.getPlugin().getServer().getScheduler().
@@ -231,24 +205,7 @@ public class ListLibraryGUI extends CommonGUI
                         () -> this.addon.getWebManager().requestEntryGitHubData(this.user, this.world, libraryEntry),
                         5L);
 
-                if (this.parentGUI != null)
-                {
-                    if (this.updateTask != null)
-                    {
-                        this.updateTask.cancel();
-                    }
-
-                    this.parentGUI.build();
-                }
-                else
-                {
-                    if (this.updateTask != null)
-                    {
-                        this.updateTask.cancel();
-                    }
-
-                    this.user.closeInventory();
-                }
+                this.build();
             }
 
             return true;
@@ -265,25 +222,66 @@ public class ListLibraryGUI extends CommonGUI
      */
     private List<String> generateEntryDescription(LibraryEntry entry)
     {
+        final String reference = Constants.DESCRIPTIONS + "library.";
+
         List<String> description = new ArrayList<>();
 
-        description.add(this.user.getTranslation(REFERENCE_DESCRIPTION + "library-author",
-            "[author]",
-            entry.getAuthor()));
+        description.add(this.user.getTranslation(reference + "author",
+            "[author]", entry.getAuthor()));
         description.add(entry.getDescription());
 
-        description.add(this.user.getTranslation(REFERENCE_DESCRIPTION + "library-gamemode",
-            "[gamemode]",
-            entry.getForGameMode()));
-        description.add(this.user.getTranslation(REFERENCE_DESCRIPTION + "library-lang",
-            "[lang]",
-            entry.getLanguage()));
-        description.add(this.user.getTranslation(REFERENCE_DESCRIPTION + "library-version",
-            "[version]",
-            entry.getVersion()));
+        description.add(this.user.getTranslation(reference + "gamemode",
+            "[gamemode]", entry.getForGameMode()));
+        description.add(this.user.getTranslation(reference + "lang",
+            "[lang]", entry.getLanguage()));
+        description.add(this.user.getTranslation(reference + "version",
+            "[version]", entry.getVersion()));
 
-        return GuiUtils.stringSplit(description,
-            this.addon.getChallengesSettings().getLoreLineLength());
+        return description;
+    }
+
+
+    /**
+     * This class allows changing icon for Generator Tier
+     */
+    private class DownloadCanceller implements PanelListener
+    {
+        /**
+         * On inventory click.
+         *
+         * @param user the user
+         * @param event the event
+         */
+        @Override
+        public void onInventoryClick(User user, InventoryClickEvent event)
+        {
+            // do nothing
+        }
+
+
+        /**
+         * On inventory close.
+         *
+         * @param event the event
+         */
+        @Override
+        public void onInventoryClose(InventoryCloseEvent event)
+        {
+            if (ListLibraryPanel.this.updateTask != null)
+            {
+                ListLibraryPanel.this.updateTask.cancel();
+            }
+        }
+
+
+        /**
+         * Setup current listener.
+         */
+        @Override
+        public void setup()
+        {
+            // Do nothing
+        }
     }
 
 
@@ -305,9 +303,4 @@ public class ListLibraryGUI extends CommonGUI
      * This variable will protect against spam-click.
      */
     private boolean blockedForDownland;
-
-    /**
-     * Reference string to description.
-     */
-    private static final String REFERENCE_DESCRIPTION = "challenges.gui.descriptions.admin.";
 }

src/main/java/world/bentobox/challenges/panel/admin/ListUsersGUI.java

@@ -1,334 +0,0 @@
-package world.bentobox.challenges.panel.admin;
-
-
-import java.util.ArrayList;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.stream.Collectors;
-
-import org.bukkit.Bukkit;
-import org.bukkit.Material;
-import org.bukkit.World;
-import org.bukkit.entity.Player;
-
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.bentobox.database.objects.Players;
-import world.bentobox.challenges.ChallengesAddon;
-import world.bentobox.challenges.managers.ChallengesManager;
-import world.bentobox.challenges.database.object.Challenge;
-import world.bentobox.challenges.panel.CommonGUI;
-import world.bentobox.challenges.panel.util.ConfirmationGUI;
-import world.bentobox.challenges.panel.util.SelectChallengeGUI;
-import world.bentobox.challenges.utils.GuiUtils;
-
-
-/**
- * This class contains methods that allows to select specific user.
- */
-public class ListUsersGUI extends CommonGUI
-{
-    // ---------------------------------------------------------------------
-    // Section: Variables
-    // ---------------------------------------------------------------------
-
-    /**
-     * List with players that should be in GUI.
-     */
-    private List<Player> onlineUsers;
-
-    /**
-     * Current operation mode.
-     */
-    private Mode operationMode;
-
-    /**
-     * Current index of view mode
-     */
-    private int modeIndex = 2;
-
-    /**
-     * This allows to switch which users should be in the list.
-     */
-    private enum ViewMode
-    {
-        ONLINE,
-        WITH_ISLAND,
-        IN_WORLD
-    }
-
-    /**
-     * This allows to decide what User Icon should do.
-     */
-    public enum Mode
-    {
-        COMPLETE,
-        RESET,
-        RESET_ALL
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Constructors
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * @param addon Addon where panel operates.
-     * @param world World from which panel was created.
-     * @param user User who created panel.
-     * @param topLabel Command top label which creates panel (f.e. island or ai)
-     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
-     * @param operationMode Indicate what should happen on player icon click.
-     */
-    public ListUsersGUI(ChallengesAddon addon,
-            World world,
-            User user,
-            Mode operationMode,
-            String topLabel,
-            String permissionPrefix)
-    {
-        this(addon, world, user, operationMode, topLabel, permissionPrefix, null);
-    }
-
-
-    /**
-     * @param addon Addon where panel operates.
-     * @param world World from which panel was created.
-     * @param user User who created panel.
-     * @param topLabel Command top label which creates panel (f.e. island or ai)
-     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
-     * @param operationMode Indicate what should happen on player icon click.
-     */
-    public ListUsersGUI(ChallengesAddon addon,
-            World world,
-            User user,
-            Mode operationMode,
-            String topLabel,
-            String permissionPrefix,
-            CommonGUI parentPanel)
-    {
-        super(addon, world, user, topLabel, permissionPrefix, parentPanel);
-        this.onlineUsers = this.collectUsers(ViewMode.IN_WORLD);
-        this.operationMode = operationMode;
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Methods
-    // ---------------------------------------------------------------------
-
-
-    @Override
-    public void build()
-    {
-        PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(
-                this.user.getTranslation("challenges.gui.title.admin.choose-user-title"));
-
-        GuiUtils.fillBorder(panelBuilder);
-
-        final int MAX_ELEMENTS = 21;
-
-        if (this.pageIndex < 0)
-        {
-            this.pageIndex = this.onlineUsers.size() / MAX_ELEMENTS;
-        }
-        else if (this.pageIndex > (this.onlineUsers.size() / MAX_ELEMENTS))
-        {
-            this.pageIndex = 0;
-        }
-
-        int playerIndex = MAX_ELEMENTS * this.pageIndex;
-
-        // I want first row to be only for navigation and return button.
-        int index = 10;
-
-        while (playerIndex < ((this.pageIndex + 1) * MAX_ELEMENTS) &&
-                playerIndex < this.onlineUsers.size() &&
-                index < 36)
-        {
-            if (!panelBuilder.slotOccupied(index))
-            {
-                panelBuilder.item(index, this.createPlayerIcon(this.onlineUsers.get(playerIndex++)));
-            }
-
-            index++;
-        }
-
-        // Add button that allows to toggle different player lists.
-        panelBuilder.item( 4, this.createToggleButton());
-
-        // Navigation buttons only if necessary
-        if (this.onlineUsers.size() > MAX_ELEMENTS)
-        {
-            panelBuilder.item(18, this.getButton(CommonButtons.PREVIOUS));
-            panelBuilder.item(26, this.getButton(CommonButtons.NEXT));
-        }
-
-        panelBuilder.item(44, this.returnButton);
-
-
-        panelBuilder.build();
-    }
-
-
-    /**
-     * This method creates button for given user. If user has island it will add valid click handler.
-     * @param player Player which button must be created.
-     * @return Player button.
-     */
-    private PanelItem createPlayerIcon(Player player)
-    {
-        int lineLength = this.addon.getChallengesSettings().getLoreLineLength();
-
-        if (this.addon.getIslands().getIsland(this.world, player.getUniqueId()) != null)
-        {
-            return new PanelItemBuilder().name(player.getName()).icon(player.getName()).clickHandler(
-                    (panel, user1, clickType, slot) -> {
-                        ChallengesManager manager = this.addon.getChallengesManager();
-                        Map<Challenge, List<String>> challengeDescriptionMap;
-
-                        switch (this.operationMode)
-                        {
-                        case COMPLETE:
-                            challengeDescriptionMap = new LinkedHashMap<>();
-
-                            for (Challenge challenge : manager.getAllChallenges(this.world))
-                            {
-                                if (!manager.isChallengeComplete(player.getUniqueId(), this.world, challenge))
-                                {
-                                    challengeDescriptionMap.put(challenge, this.generateChallengeDescription(challenge, player));
-                                }
-                            }
-
-                            new SelectChallengeGUI(this.user, challengeDescriptionMap, lineLength, (status, valueSet) -> {
-                                if (status)
-                                {
-                                    valueSet.forEach(challenge -> manager.setChallengeComplete(player.getUniqueId(), this.world, challenge, this.user.getUniqueId()));
-                                }
-
-                                this.build();
-                            });
-                            break;
-                        case RESET:
-                            challengeDescriptionMap = new LinkedHashMap<>();
-
-                            for (Challenge challenge : manager.getAllChallenges(this.world))
-                            {
-                                if (manager.isChallengeComplete(player.getUniqueId(), this.world, challenge))
-                                {
-                                    challengeDescriptionMap.put(challenge, this.generateChallengeDescription(challenge, player));
-                                }
-                            }
-
-                            new SelectChallengeGUI(this.user, challengeDescriptionMap, lineLength, (status, valueSet) -> {
-                                if (status)
-                                {
-                                    valueSet.forEach(challenge -> manager.resetChallenge(player.getUniqueId(), this.world, challenge, this.user.getUniqueId()));
-                                }
-
-                                this.build();
-                            });
-                            break;
-                        case RESET_ALL:
-                            new ConfirmationGUI(this.user, status -> {
-                                if (status)
-                                {
-                                    manager.resetAllChallenges(player.getUniqueId(), this.world, this.user.getUniqueId());
-                                }
-
-                                this.build();
-                            });
-                            break;
-                        }
-
-                        return true;
-                    }).build();
-        }
-        else
-        {
-            return new PanelItemBuilder().
-                    name(player.getName()).
-                    icon(Material.BARRIER).
-                    description(GuiUtils.stringSplit(this.user.getTranslation("general.errors.player-has-no-island"), lineLength)).
-                    clickHandler((panel, user1, clickType, slot) -> false).
-                    build();
-        }
-    }
-
-
-    /**
-     * This method collects users based on view mode.
-     * @param mode Given view mode.
-     * @return List with players in necessary view mode.
-     */
-    private List<Player> collectUsers(ViewMode mode)
-    {
-        if (mode.equals(ViewMode.ONLINE))
-        {
-            return new ArrayList<>(Bukkit.getOnlinePlayers());
-        }
-        else if (mode.equals(ViewMode.WITH_ISLAND))
-        {
-            return this.addon.getPlayers().getPlayers().stream().
-                    filter(player -> this.addon.getIslands().getIsland(this.world, player.getPlayerUUID()) != null).
-                    map(Players::getPlayer).
-                    collect(Collectors.toList());
-        }
-        else
-        {
-            return  new ArrayList<>(this.world.getPlayers());
-        }
-    }
-
-
-    /**
-     * This method creates Player List view Mode toggle button.
-     * @return Button that toggles through player view mode.
-     */
-    private PanelItem createToggleButton()
-    {
-        List<String> description = new ArrayList<>(ViewMode.values().length + 1);
-        description.add(this.user.getTranslation("challenges.gui.descriptions.admin.toggle-user-list"));
-        description.add((ViewMode.ONLINE == ViewMode.values()[this.modeIndex] ? "&2" : "&c") +
-                this.user.getTranslation("challenges.gui.descriptions.admin.mode-online"));
-        description.add((ViewMode.WITH_ISLAND == ViewMode.values()[this.modeIndex] ? "&2" : "&c") +
-                this.user.getTranslation("challenges.gui.descriptions.admin.mode-in-world"));
-        description.add((ViewMode.IN_WORLD == ViewMode.values()[this.modeIndex] ? "&2" : "&c") +
-                this.user.getTranslation("challenges.gui.descriptions.admin.mode-with-island"));
-
-        return new PanelItemBuilder().
-                name(this.user.getTranslation("challenges.gui.buttons.admin.toggle-user-list")).
-                description(GuiUtils.stringSplit(description, this.addon.getChallengesSettings().getLoreLineLength())).
-                icon(Material.STONE_BUTTON).
-                clickHandler(
-                        (panel, user1, clickType, slot) -> {
-                            if (clickType.isRightClick())
-                            {
-                                this.modeIndex--;
-
-                                if (this.modeIndex < 0)
-                                {
-                                    this.modeIndex = ViewMode.values().length - 1;
-                                }
-                            }
-                            else
-                            {
-                                this.modeIndex++;
-
-                                if (this.modeIndex >= ViewMode.values().length)
-                                {
-                                    this.modeIndex = 0;
-                                }
-                            }
-
-                            this.onlineUsers = this.collectUsers(ViewMode.values()[this.modeIndex]);
-                            this.pageIndex = 0;
-                            this.build();
-                            return true;
-                        }).build();
-    }
-}

src/main/java/world/bentobox/challenges/panel/admin/ListUsersPanel.java

@@ -0,0 +1,376 @@
+package world.bentobox.challenges.panel.admin;
+
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+import org.bukkit.Bukkit;
+import org.bukkit.Material;
+import org.bukkit.World;
+import org.bukkit.entity.Player;
+
+import world.bentobox.bentobox.api.panels.PanelItem;
+import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
+import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
+import world.bentobox.bentobox.api.user.User;
+import world.bentobox.bentobox.database.objects.Island;
+import world.bentobox.bentobox.database.objects.Players;
+import world.bentobox.challenges.ChallengesAddon;
+import world.bentobox.challenges.database.object.Challenge;
+import world.bentobox.challenges.panel.CommonPagedPanel;
+import world.bentobox.challenges.panel.CommonPanel;
+import world.bentobox.challenges.panel.util.ChallengeSelector;
+import world.bentobox.challenges.utils.Constants;
+import world.bentobox.challenges.utils.GuiUtils;
+import world.bentobox.challenges.utils.Utils;
+
+
+/**
+ * This class contains methods that allows to select specific user.
+ */
+public class ListUsersPanel extends CommonPagedPanel
+{
+    // ---------------------------------------------------------------------
+    // Section: Constructors
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * @param addon Addon where panel operates.
+     * @param world World from which panel was created.
+     * @param user User who created panel.
+     * @param topLabel Command top label which creates panel (f.e. island or ai)
+     * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
+     * @param operationMode Indicate what should happen on player icon click.
+     */
+    private ListUsersPanel(ChallengesAddon addon,
+        User user,
+        World world,
+        String topLabel,
+        String permissionPrefix,
+        Mode operationMode)
+    {
+        super(addon, user, world, topLabel, permissionPrefix);
+        this.onlineUsers = this.collectUsers(ViewMode.IN_WORLD);
+        this.operationMode = operationMode;
+    }
+
+
+    /**
+     * @param operationMode Indicate what should happen on player icon click.
+     */
+    private ListUsersPanel(CommonPanel panel, Mode operationMode)
+    {
+        super(panel);
+        this.onlineUsers = this.collectUsers(ViewMode.IN_WORLD);
+        this.operationMode = operationMode;
+    }
+
+
+    /**
+     * Open the Challenges Admin GUI.
+     *
+     * @param addon the addon
+     * @param world the world
+     * @param user the user
+     * @param topLabel the top label
+     * @param permissionPrefix the permission prefix
+     */
+    public static void open(ChallengesAddon addon,
+        World world,
+        User user,
+        String topLabel,
+        String permissionPrefix,
+        Mode mode)
+    {
+        new ListUsersPanel(addon, user, world, topLabel, permissionPrefix, mode).build();
+    }
+
+
+    /**
+     * Open the Challenges Admin GUI.
+     */
+    public static void open(CommonPanel parentGUI, Mode mode)
+    {
+        new ListUsersPanel(parentGUI, mode).build();
+    }
+
+
+    // ---------------------------------------------------------------------
+    // Section: Methods
+    // ---------------------------------------------------------------------
+
+
+    @Override
+    protected void build()
+    {
+        PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(
+            this.user.getTranslation(Constants.TITLE + "choose-player"));
+
+        GuiUtils.fillBorder(panelBuilder);
+
+        this.populateElements(panelBuilder,
+            this.onlineUsers,
+            o -> this.createPlayerIcon((Player) o));
+
+        // Add button that allows to toggle different player lists.
+        panelBuilder.item( 4, this.createToggleButton());
+        panelBuilder.item(44, this.returnButton);
+
+        panelBuilder.build();
+    }
+
+
+    /**
+     * This method creates button for given user. If user has island it will add valid click handler.
+     * @param player Player which button must be created.
+     * @return Player button.
+     */
+    private PanelItem createPlayerIcon(Player player)
+    {
+        final String reference = Constants.BUTTON + "player.";
+
+        Island island = this.addon.getIslands().getIsland(this.world, player.getUniqueId());
+
+        if (island == null)
+        {
+            return new PanelItemBuilder().
+                name(this.user.getTranslation(reference + "name", "[name]", player.getName())).
+                icon(Material.BARRIER).
+                description(this.user.getTranslation(reference + "no-island")).
+                build();
+        }
+
+        List<String> description = new ArrayList<>(4);
+        description.add(this.user.getTranslation(reference + "description",
+            "[owner]", this.addon.getPlayers().getName(island.getOwner())));
+
+        // Is owner in his own island member set? I assume yes. Need testing.
+        if (island.getMemberSet().size() > 1)
+        {
+            description.add(this.user.getTranslation(reference + "members"));
+            island.getMemberSet().forEach(member -> {
+                if (member != island.getOwner())
+                {
+                    description.add(this.user.getTranslation(reference + "member",
+                        "[name]", this.addon.getPlayers().getName(member)));
+                }
+            });
+        }
+
+        description.add("");
+
+        if (this.operationMode == Mode.RESET_ALL && this.selectedPlayer != null)
+        {
+            description.add(this.user.getTranslation(Constants.TIPS + "click-to-reset-all"));
+        }
+        else
+        {
+            description.add(this.user.getTranslation(Constants.TIPS + "click-to-choose"));
+        }
+
+        return new PanelItemBuilder().
+            name(this.user.getTranslation(reference + "name", "[name]", player.getName())).
+            icon(player.getName()).
+            description(description).
+            glow(this.operationMode == Mode.RESET_ALL && this.selectedPlayer == player).
+            clickHandler((panel, user1, clickType, i) -> {
+                switch (this.operationMode)
+                {
+                    case COMPLETE -> {
+                        // Get all challenge that is in current level.
+                        List<Challenge> challengeList = this.manager.getAllChallenges(this.world);
+
+                        // Generate descriptions for these challenges
+                        Map<Challenge, List<String>> challengeDescriptionMap = challengeList.stream().
+                            filter(challenge -> !this.manager.isChallengeComplete(player.getUniqueId(), this.world, challenge)).
+                            collect(Collectors.toMap(challenge -> challenge,
+                                challenge -> this.generateChallengeDescription(challenge, User.getInstance(player)),
+                                (a, b) -> b,
+                                () -> new LinkedHashMap<>(challengeList.size())));
+
+                        // Open select gui
+                        ChallengeSelector.open(this.user,
+                            Material.LIME_STAINED_GLASS_PANE,
+                            challengeDescriptionMap,
+                            (status, valueSet) -> {
+                                if (status)
+                                {
+                                    valueSet.forEach(challenge ->
+                                        manager.setChallengeComplete(player.getUniqueId(),
+                                            this.world,
+                                            challenge,
+                                            this.user.getUniqueId()));
+                                }
+
+                            this.build();
+                        });
+                    }
+                    case RESET -> {
+                        // Get all challenge that is in current level.
+                        List<Challenge> challengeList = this.manager.getAllChallenges(this.world);
+
+                        // Generate descriptions for these challenges
+                        Map<Challenge, List<String>> challengeDescriptionMap = challengeList.stream().
+                            filter(challenge -> this.manager.isChallengeComplete(player.getUniqueId(), this.world, challenge)).
+                            collect(Collectors.toMap(challenge -> challenge,
+                                challenge -> this.generateChallengeDescription(challenge, User.getInstance(player)),
+                                (a, b) -> b,
+                                () -> new LinkedHashMap<>(challengeList.size())));
+
+                        // Open select gui
+                        ChallengeSelector.open(this.user,
+                            Material.ORANGE_STAINED_GLASS_PANE,
+                            challengeDescriptionMap,
+                            (status, valueSet) -> {
+                                if (status)
+                                {
+                                    valueSet.forEach(challenge ->
+                                        this.manager.resetChallenge(player.getUniqueId(),
+                                            this.world,
+                                            challenge,
+                                            this.user.getUniqueId()));
+                                }
+
+                            this.build();
+                        });
+                    }
+                    case RESET_ALL -> {
+                        if (this.selectedPlayer == null)
+                        {
+                            this.selectedPlayer = player;
+                        }
+                        else
+                        {
+                            this.manager.resetAllChallenges(player.getUniqueId(), this.world, this.user.getUniqueId());
+                            this.selectedPlayer = null;
+                        }
+
+                        this.build();
+                    }
+                }
+
+                return true;
+            }).
+            build();
+    }
+
+
+    /**
+     * This method collects users based on view mode.
+     * @param mode Given view mode.
+     * @return List with players in necessary view mode.
+     */
+    private List<Player> collectUsers(ViewMode mode)
+    {
+        return switch (mode) {
+            case ONLINE -> new ArrayList<>(Bukkit.getOnlinePlayers());
+            case WITH_ISLAND -> this.addon.getPlayers().getPlayers().stream().
+                filter(player -> this.addon.getIslands().getIsland(this.world, player.getPlayerUUID()) != null).
+                map(Players::getPlayer).
+                collect(Collectors.toList());
+            default -> new ArrayList<>(this.world.getPlayers());
+        };
+    }
+
+
+    /**
+     * This method creates Player List view Mode toggle button.
+     * @return Button that toggles through player view mode.
+     */
+    private PanelItem createToggleButton()
+    {
+        final String reference = Constants.BUTTON + "player_list.";
+
+        List<String> description = new ArrayList<>(5);
+
+        description.add(this.user.getTranslation(reference + "description"));
+        description.add(this.user.getTranslation(reference +
+            (ViewMode.ONLINE == this.mode ? "enabled" : "disabled")) +
+            this.user.getTranslation(reference + "online"));
+        description.add(this.user.getTranslation(reference +
+            (ViewMode.WITH_ISLAND == this.mode ? "enabled" : "disabled")) +
+            this.user.getTranslation(reference + "with_island"));
+        description.add(this.user.getTranslation(reference +
+            (ViewMode.IN_WORLD == this.mode ? "enabled" : "disabled")) +
+            this.user.getTranslation(reference + "in_world"));
+
+        description.add("");
+        description.add(this.user.getTranslation(Constants.TIPS + "left-click-to-cycle"));
+        description.add(this.user.getTranslation(Constants.TIPS + "right-click-to-cycle"));
+
+        return new PanelItemBuilder().
+            name(this.user.getTranslation(reference + "name")).
+            icon(Material.STONE_BUTTON).
+            description(description).
+            clickHandler((panel, user1, clickType, slot) -> {
+                if (clickType.isRightClick())
+                {
+                    this.mode = Utils.getPreviousValue(ViewMode.values(), this.mode);
+                    this.onlineUsers = this.collectUsers(this.mode);
+                }
+                else
+                {
+                    this.mode = Utils.getNextValue(ViewMode.values(), this.mode);
+                    this.onlineUsers = this.collectUsers(this.mode);
+                }
+
+                this.build();
+                return true;
+            }).build();
+    }
+
+
+// ---------------------------------------------------------------------
+// Section: Enums
+// ---------------------------------------------------------------------
+
+
+    /**
+     * This allows to switch which users should be in the list.
+     */
+    private enum ViewMode
+    {
+        ONLINE,
+        WITH_ISLAND,
+        IN_WORLD
+    }
+
+    /**
+     * This allows to decide what User Icon should do.
+     */
+    public enum Mode
+    {
+        COMPLETE,
+        RESET,
+        RESET_ALL
+    }
+
+
+// ---------------------------------------------------------------------
+// Section: Variables
+// ---------------------------------------------------------------------
+
+    /**
+     * List with players that should be in GUI.
+     */
+    private List<Player> onlineUsers;
+
+    /**
+     * Current operation mode.
+     */
+    private final Mode operationMode;
+
+    /**
+     * Current index of view mode
+     */
+    private ViewMode mode = ViewMode.ONLINE;
+
+    /**
+     * Stores clicked player.
+     */
+    private Player selectedPlayer;
+}

src/main/java/world/bentobox/challenges/panel/admin/ManageBlocksGUI.java

@@ -1,241 +0,0 @@
-package world.bentobox.challenges.panel.admin;
-
-
-import java.util.ArrayList;
-import java.util.Comparator;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-
-import org.apache.commons.lang.WordUtils;
-import org.bukkit.Material;
-import org.bukkit.World;
-
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.ChallengesAddon;
-import world.bentobox.challenges.panel.CommonGUI;
-import world.bentobox.challenges.panel.util.NumberGUI;
-import world.bentobox.challenges.panel.util.SelectBlocksGUI;
-import world.bentobox.challenges.utils.GuiUtils;
-
-
-/**
- * This class allows to edit material that are in required material map.
- */
-public class ManageBlocksGUI extends CommonGUI
-{
-	public ManageBlocksGUI(ChallengesAddon addon,
-		World world,
-		User user,
-		Map<Material, Integer> materialMap,
-		String topLabel,
-		String permissionPrefix,
-		CommonGUI parentGUI)
-	{
-		super(addon, world, user, topLabel, permissionPrefix, parentGUI);
-		this.materialMap = materialMap;
-
-		this.materialList = new ArrayList<>(this.materialMap.keySet());
-
-		// Sort materials by their ordinal value.
-		this.materialList.sort(Comparator.comparing(Enum::ordinal));
-
-		this.selectedMaterials = new HashSet<>();
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Methods
-// ---------------------------------------------------------------------
-
-
-	/**
-	 * This method builds all necessary elements in GUI panel.
-	 */
-	@Override
-	public void build()
-	{
-		PanelBuilder panelBuilder = new PanelBuilder().user(this.user).
-			name(this.user.getTranslation("challenges.gui.title.admin.manage-blocks"));
-
-		// Create nice border.
-		GuiUtils.fillBorder(panelBuilder);
-
-		panelBuilder.item(3, this.createButton(Button.ADD));
-		panelBuilder.item(5, this.createButton(Button.REMOVE));
-
-		final int MAX_ELEMENTS = 21;
-
-		if (this.pageIndex < 0)
-		{
-			this.pageIndex = this.materialList.size() / MAX_ELEMENTS;
-		}
-		else if (this.pageIndex > (this.materialList.size() / MAX_ELEMENTS))
-		{
-			this.pageIndex = 0;
-		}
-
-		int entitiesIndex = MAX_ELEMENTS * this.pageIndex;
-
-		// I want first row to be only for navigation and return button.
-		int index = 10;
-
-		while (entitiesIndex < ((this.pageIndex + 1) * MAX_ELEMENTS) &&
-			entitiesIndex < this.materialList.size() &&
-			index < 36)
-		{
-			if (!panelBuilder.slotOccupied(index))
-			{
-				panelBuilder.item(index, this.createElementButton(this.materialList.get(entitiesIndex++)));
-			}
-
-			index++;
-		}
-
-		// Navigation buttons only if necessary
-		if (this.materialList.size() > MAX_ELEMENTS)
-		{
-			panelBuilder.item(18, this.getButton(CommonButtons.PREVIOUS));
-			panelBuilder.item(26, this.getButton(CommonButtons.NEXT));
-		}
-
-		// Add return button.
-		panelBuilder.item(44, this.returnButton);
-
-		panelBuilder.build();
-	}
-
-
-	/**
-	 * This method creates PanelItem button of requested type.
-	 * @param button Button which must be created.
-	 * @return new PanelItem with requested functionality.
-	 */
-	private PanelItem createButton(Button button)
-	{
-		int lineLength = this.addon.getChallengesSettings().getLoreLineLength();
-		PanelItemBuilder builder = new PanelItemBuilder();
-
-		switch (button)
-		{
-			case ADD:
-				builder.name(this.user.getTranslation("challenges.gui.buttons.admin.add"));
-				builder.icon(Material.BUCKET);
-				builder.clickHandler((panel, user1, clickType, slot) -> {
-
-					new SelectBlocksGUI(this.user, false, new HashSet<>(this.materialList), (status, materials) -> {
-						if (status)
-						{
-							materials.forEach(material -> {
-								this.materialMap.put(material, 1);
-								this.materialList.add(material);
-							});
-						}
-
-						this.build();
-					});
-					return true;
-				});
-				break;
-			case REMOVE:
-				builder.name(this.user.getTranslation("challenges.gui.buttons.admin.remove-selected"));
-				builder.description(GuiUtils.stringSplit(this.user.getTranslation("challenges.gui.descriptions.admin.remove-selected"), lineLength));
-				builder.icon(Material.LAVA_BUCKET);
-				builder.clickHandler((panel, user1, clickType, slot) -> {
-					this.materialMap.keySet().removeAll(this.selectedMaterials);
-					this.materialList.removeAll(this.selectedMaterials);
-					this.build();
-					return true;
-				});
-				break;
-		}
-
-		return builder.build();
-	}
-
-
-	/**
-	 * This method creates button for given material.
-	 * @param material material which button must be created.
-	 * @return new Button for material.
-	 */
-	private PanelItem createElementButton(Material material)
-	{
-		return new PanelItemBuilder().
-			name(WordUtils.capitalize(material.name().toLowerCase().replace("_", " "))).
-			icon(GuiUtils.getMaterialItem(material, this.materialMap.get(material))).
-			description(this.selectedMaterials.contains(material) ?
-				this.user.getTranslation("challenges.gui.descriptions.admin.selected") : "").
-			clickHandler((panel, user1, clickType, slot) -> {
-				// On right click change which entities are selected for deletion.
-				if (clickType.isRightClick())
-				{
-					if (!this.selectedMaterials.add(material))
-					{
-						// Remove material if it is already selected
-						this.selectedMaterials.remove(material);
-					}
-
-					this.build();
-				}
-				else
-				{
-					new NumberGUI(this.user,
-						this.materialMap.get(material),
-						1,
-						this.addon.getChallengesSettings().getLoreLineLength(),
-						(status, value) -> {
-							if (status)
-							{
-								// Update value only when something changes.
-								this.materialMap.put(material, value);
-							}
-
-							this.build();
-						});
-				}
-				return true;
-			}).
-			glow(this.selectedMaterials.contains(material)).
-			build();
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Enums
-// ---------------------------------------------------------------------
-
-
-	/**
-	 * Functional buttons in current GUI.
-	 */
-	private enum Button
-	{
-		ADD,
-		REMOVE
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Variables
-// ---------------------------------------------------------------------
-
-	/**
-	 * Contains selected materials.
-	 */
-	private Set<Material> selectedMaterials;
-
-	/**
-	 * List of materials to avoid order issues.
-	 */
-	private List<Material> materialList;
-
-	/**
-	 * List of required materials.
-	 */
-	private Map<Material, Integer> materialMap;
-}

src/main/java/world/bentobox/challenges/panel/admin/ManageBlocksPanel.java

@@ -0,0 +1,282 @@
+package world.bentobox.challenges.panel.admin;
+
+
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.function.Consumer;
+
+import org.bukkit.Material;
+import org.bukkit.inventory.ItemStack;
+
+import world.bentobox.bentobox.api.panels.PanelItem;
+import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
+import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
+import world.bentobox.challenges.panel.CommonPagedPanel;
+import world.bentobox.challenges.panel.CommonPanel;
+import world.bentobox.challenges.panel.ConversationUtils;
+import world.bentobox.challenges.panel.util.MultiBlockSelector;
+import world.bentobox.challenges.utils.Constants;
+import world.bentobox.challenges.utils.GuiUtils;
+import world.bentobox.challenges.utils.Utils;
+
+
+/**
+ * This class allows to edit material that are in required material map.
+ */
+public class ManageBlocksPanel extends CommonPagedPanel
+{
+	private ManageBlocksPanel(CommonPanel parentGUI, Map<Material, Integer> materialMap)
+	{
+		super(parentGUI);
+		this.materialMap = materialMap;
+		this.materialList = new ArrayList<>(this.materialMap.keySet());
+
+		// Sort materials by their ordinal value.
+		this.materialList.sort(Comparator.comparing(Enum::ordinal));
+
+		this.selectedMaterials = new HashSet<>();
+	}
+
+
+	/**
+	 * Open the Challenges Admin GUI.
+	 */
+	public static void open(CommonPanel parentGUI, Map<Material, Integer> materialMap)
+	{
+		new ManageBlocksPanel(parentGUI, materialMap).build();
+	}
+
+
+// ---------------------------------------------------------------------
+// Section: Methods
+// ---------------------------------------------------------------------
+
+
+	/**
+	 * This method builds all necessary elements in GUI panel.
+	 */
+	@Override
+	public void build()
+	{
+		PanelBuilder panelBuilder = new PanelBuilder().user(this.user).
+			name(this.user.getTranslation(Constants.TITLE + "manage-blocks"));
+
+		// Create nice border.
+		GuiUtils.fillBorder(panelBuilder);
+
+		panelBuilder.item(3, this.createButton(Button.ADD_BLOCK));
+		panelBuilder.item(5, this.createButton(Button.REMOVE_BLOCK));
+
+		this.populateElements(panelBuilder,
+			this.materialList,
+			o -> this.createElementButton((Material) o));
+
+		// Add return button.
+		panelBuilder.item(44, this.returnButton);
+
+		panelBuilder.build();
+	}
+
+
+	/**
+	 * This method creates PanelItem button of requested type.
+	 * @param button Button which must be created.
+	 * @return new PanelItem with requested functionality.
+	 */
+	private PanelItem createButton(Button button)
+	{
+		final String reference = Constants.BUTTON + button.name().toLowerCase() + ".";
+
+		final String name = this.user.getTranslation(reference + "name");
+		final List<String> description = new ArrayList<>(3);
+		description.add(this.user.getTranslation(reference + "description"));
+
+		ItemStack icon;
+		PanelItem.ClickHandler clickHandler;
+		boolean glow;
+
+		switch (button)
+		{
+			case ADD_BLOCK -> {
+				icon = new ItemStack(Material.BUCKET);
+				clickHandler = (panel, user1, clickType, slot) ->
+				{
+					MultiBlockSelector.open(this.user,
+						MultiBlockSelector.Mode.BLOCKS,
+						new HashSet<>(this.materialList),
+						(status, materials) ->
+						{
+							if (status)
+							{
+								materials.forEach(material ->
+								{
+									this.materialMap.put(material, 1);
+									this.materialList.add(material);
+								});
+							}
+
+							this.build();
+						});
+					return true;
+				};
+				glow = false;
+
+				description.add("");
+				description.add(this.user.getTranslation(Constants.TIPS + "click-to-add"));
+			}
+			case REMOVE_BLOCK -> {
+
+				if (!this.selectedMaterials.isEmpty())
+				{
+					description.add(this.user.getTranslation(reference + "title"));
+					this.selectedMaterials.forEach(material -> {
+						description.add(this.user.getTranslation(reference + "material",
+							"[material]", Utils.prettifyObject(material, this.user)));
+					});
+				}
+
+				icon = new ItemStack(Material.LAVA_BUCKET);
+
+				clickHandler = (panel, user1, clickType, slot) ->
+				{
+					if (!this.selectedMaterials.isEmpty())
+					{
+						this.materialMap.keySet().removeAll(this.selectedMaterials);
+						this.materialList.removeAll(this.selectedMaterials);
+						this.selectedMaterials.clear();
+						this.build();
+					}
+
+					return true;
+				};
+
+				glow = !this.selectedMaterials.isEmpty();
+
+				description.add("");
+				description.add(this.user.getTranslation(Constants.TIPS + "click-to-remove"));
+			}
+			default -> {
+				icon = new ItemStack(Material.PAPER);
+				clickHandler = null;
+				glow = false;
+			}
+		}
+
+		return new PanelItemBuilder().
+			icon(icon).
+			name(name).
+			description(description).
+			clickHandler(clickHandler).
+			glow(glow).
+			build();
+	}
+
+
+	/**
+	 * This method creates button for given material.
+	 * @param material material which button must be created.
+	 * @return new Button for material.
+	 */
+	private PanelItem createElementButton(Material material)
+	{
+		final String reference = Constants.BUTTON + "material.";
+
+		List<String> description = new ArrayList<>();
+
+		if (this.selectedMaterials.contains(material))
+		{
+			description.add(this.user.getTranslation(reference + "selected"));
+		}
+
+		description.add("");
+		description.add(this.user.getTranslation(Constants.TIPS + "left-click-to-choose"));
+
+		if (this.selectedMaterials.contains(material))
+		{
+			description.add(this.user.getTranslation(Constants.TIPS + "right-click-to-deselect"));
+		}
+		else
+		{
+			description.add(this.user.getTranslation(Constants.TIPS + "right-click-to-select"));
+		}
+
+		return new PanelItemBuilder().
+			name(this.user.getTranslation(reference + "name", "[material]",
+				Utils.prettifyObject(material, this.user))).
+			icon(GuiUtils.getMaterialItem(material, this.materialMap.get(material))).
+			description(description).
+			clickHandler((panel, user1, clickType, slot) -> {
+				// On right click change which entities are selected for deletion.
+				if (clickType.isRightClick())
+				{
+					if (!this.selectedMaterials.add(material))
+					{
+						// Remove material if it is already selected
+						this.selectedMaterials.remove(material);
+					}
+
+					this.build();
+				}
+				else
+				{
+					Consumer<Number> numberConsumer = number -> {
+						if (number != null)
+						{
+							this.materialMap.put(material, number.intValue());
+						}
+
+						// reopen panel
+						this.build();
+					};
+
+					ConversationUtils.createNumericInput(numberConsumer,
+						this.user,
+						this.user.getTranslation(Constants.CONVERSATIONS + "input-number"),
+						1,
+						Integer.MAX_VALUE);
+				}
+				return true;
+			}).
+			glow(this.selectedMaterials.contains(material)).
+			build();
+	}
+
+
+// ---------------------------------------------------------------------
+// Section: Enums
+// ---------------------------------------------------------------------
+
+
+	/**
+	 * Functional buttons in current GUI.
+	 */
+	private enum Button
+	{
+		ADD_BLOCK,
+		REMOVE_BLOCK
+	}
+
+
+// ---------------------------------------------------------------------
+// Section: Variables
+// ---------------------------------------------------------------------
+
+	/**
+	 * Contains selected materials.
+	 */
+	private final Set<Material> selectedMaterials;
+
+	/**
+	 * List of materials to avoid order issues.
+	 */
+	private final List<Material> materialList;
+
+	/**
+	 * List of required materials.
+	 */
+	private final Map<Material, Integer> materialMap;
+}

src/main/java/world/bentobox/challenges/panel/admin/ManageEntitiesGUI.java

@@ -1,258 +0,0 @@
-package world.bentobox.challenges.panel.admin;
-
-
-import java.util.ArrayList;
-import java.util.Comparator;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-
-import org.apache.commons.lang.WordUtils;
-import org.bukkit.Material;
-import org.bukkit.World;
-import org.bukkit.entity.EntityType;
-
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.ChallengesAddon;
-import world.bentobox.challenges.panel.CommonGUI;
-import world.bentobox.challenges.panel.util.NumberGUI;
-import world.bentobox.challenges.panel.util.SelectEntityGUI;
-import world.bentobox.challenges.utils.GuiUtils;
-
-
-/**
- * This class allows to edit entities that are in required entities map.
- */
-public class ManageEntitiesGUI extends CommonGUI
-{
-	public ManageEntitiesGUI(ChallengesAddon addon,
-		World world,
-		User user,
-		Map<EntityType, Integer> requiredEntities,
-		String topLabel,
-		String permissionPrefix,
-		CommonGUI parentGUI)
-	{
-		super(addon, world, user, topLabel, permissionPrefix, parentGUI);
-		this.requiredEntities = requiredEntities;
-
-		this.entityList = new ArrayList<>(this.requiredEntities.keySet());
-		this.entityList.sort(Comparator.comparing(Enum::name));
-
-		this.selectedEntities = new HashSet<>(EntityType.values().length);
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Methods
-// ---------------------------------------------------------------------
-
-
-	/**
-	 * This method builds all necessary elements in GUI panel.
-	 */
-	@Override
-	public void build()
-	{
-		PanelBuilder panelBuilder = new PanelBuilder().user(this.user).
-			name(this.user.getTranslation("challenges.gui.title.admin.manage-entities"));
-
-		// create border
-		GuiUtils.fillBorder(panelBuilder);
-
-		panelBuilder.item(3, this.createButton(Button.ADD));
-		panelBuilder.item(5, this.createButton(Button.REMOVE));
-		panelBuilder.item(8, this.createButton(Button.SWITCH));
-
-		final int MAX_ELEMENTS = 21;
-
-		if (this.pageIndex < 0)
-		{
-			this.pageIndex = this.entityList.size() / MAX_ELEMENTS;
-		}
-		else if (this.pageIndex > (this.entityList.size() / MAX_ELEMENTS))
-		{
-			this.pageIndex = 0;
-		}
-
-		int entitiesIndex = MAX_ELEMENTS * this.pageIndex;
-
-		// I want first row to be only for navigation and return button.
-		int index = 10;
-
-		while (entitiesIndex < ((this.pageIndex + 1) * MAX_ELEMENTS) &&
-			entitiesIndex < this.entityList.size() &&
-			index < 26)
-		{
-			if (!panelBuilder.slotOccupied(index))
-			{
-				panelBuilder.item(index, this.createEntityButton(this.entityList.get(entitiesIndex++)));
-			}
-
-			index++;
-		}
-
-		// Navigation buttons only if necessary
-		if (this.entityList.size() > MAX_ELEMENTS)
-		{
-			panelBuilder.item(18, this.getButton(CommonButtons.PREVIOUS));
-			panelBuilder.item(26, this.getButton(CommonButtons.NEXT));
-		}
-
-		// Add return button.
-		panelBuilder.item(44, this.returnButton);
-
-		panelBuilder.build();
-	}
-
-
-	/**
-	 * This method creates PanelItem button of requested type.
-	 * @param button Button which must be created.
-	 * @return new PanelItem with requested functionality.
-	 */
-	private PanelItem createButton(Button button)
-	{
-		int lineLength = this.addon.getChallengesSettings().getLoreLineLength();
-		PanelItemBuilder builder = new PanelItemBuilder();
-
-		switch (button)
-		{
-			case ADD:
-				builder.name(this.user.getTranslation("challenges.gui.buttons.admin.add"));
-				builder.icon(Material.BUCKET);
-				builder.clickHandler((panel, user1, clickType, slot) -> {
-					new SelectEntityGUI(this.user, this.requiredEntities.keySet(), this.asEggs, (status, entities) -> {
-						if (status)
-						{
-							entities.forEach(entity -> {
-								this.requiredEntities.put(entity, 1);
-								this.entityList.add(entity);
-							});
-						}
-
-						this.build();
-					});
-					return true;
-				});
-				break;
-			case REMOVE:
-				builder.name(this.user.getTranslation("challenges.gui.buttons.admin.remove-selected"));
-				builder.description(GuiUtils.stringSplit(this.user.getTranslation("challenges.gui.descriptions.admin.remove-selected"), lineLength));
-				builder.icon(Material.LAVA_BUCKET);
-				builder.clickHandler((panel, user1, clickType, slot) -> {
-					this.requiredEntities.keySet().removeAll(this.selectedEntities);
-					this.entityList.removeAll(this.selectedEntities);
-					this.build();
-					return true;
-				});
-				break;
-			case SWITCH:
-				builder.name(this.user.getTranslation("challenges.gui.buttons.admin.show-eggs"));
-				builder.description(GuiUtils.stringSplit(this.user.getTranslation("challenges.gui.descriptions.admin.show-eggs"), lineLength));
-				builder.icon(this.asEggs ? Material.EGG : Material.PLAYER_HEAD);
-				builder.clickHandler((panel, user1, clickType, slot) -> {
-					this.asEggs = !this.asEggs;
-					this.build();
-					return true;
-				});
-				break;
-		}
-
-		return builder.build();
-	}
-
-
-	/**
-	 * This method creates button for given entity.
-	 * @param entity Entity which button must be created.
-	 * @return new Button for entity.
-	 */
-	private PanelItem createEntityButton(EntityType entity)
-	{
-		return new PanelItemBuilder().
-			name(WordUtils.capitalize(entity.name().toLowerCase().replace("_", " "))).
-			description(this.selectedEntities.contains(entity) ?
-				this.user.getTranslation("challenges.gui.descriptions.admin.selected") : "").
-			icon(this.asEggs ?
-				GuiUtils.getEntityEgg(entity, this.requiredEntities.get(entity)) :
-				GuiUtils.getEntityHead(entity, this.requiredEntities.get(entity))).
-			clickHandler((panel, user1, clickType, slot) -> {
-				// On right click change which entities are selected for deletion.
-				if (clickType.isRightClick())
-				{
-					if (!this.selectedEntities.add(entity))
-					{
-						// Remove entity if it is already selected
-						this.selectedEntities.remove(entity);
-					}
-
-					this.build();
-				}
-				else
-				{
-					new NumberGUI(this.user,
-						this.requiredEntities.get(entity),
-						1,
-						this.addon.getChallengesSettings().getLoreLineLength(),
-						(status, value) -> {
-							if (status)
-							{
-								// Update value only when something changes.
-								this.requiredEntities.put(entity, value);
-							}
-
-							this.build();
-						});
-				}
-				return true;
-			}).
-			glow(this.selectedEntities.contains(entity)).
-			build();
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Enums
-// ---------------------------------------------------------------------
-
-
-	/**
-	 * Functional buttons in current GUI.
-	 */
-	private enum Button
-	{
-		ADD,
-		REMOVE,
-		SWITCH
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Variables
-// ---------------------------------------------------------------------
-
-	/**
-	 * List with entities to avoid list irregularities.
-	 */
-	private List<EntityType> entityList;
-
-	/**
-	 * Set with entities that are selected.
-	 */
-	private Set<EntityType> selectedEntities;
-
-	/**
-	 * Map that contains all entities and their cound.
-	 */
-	private Map<EntityType, Integer> requiredEntities;
-
-	/**
-	 * Boolean indicate if entities should be displayed as eggs or mob heads.
-	 */
-	private boolean asEggs;
-}

src/main/java/world/bentobox/challenges/panel/admin/ManageEntitiesPanel.java

@@ -0,0 +1,302 @@
+package world.bentobox.challenges.panel.admin;
+
+
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.function.Consumer;
+
+import org.bukkit.Material;
+import org.bukkit.entity.EntityType;
+import org.bukkit.inventory.ItemStack;
+
+import world.bentobox.bentobox.api.panels.PanelItem;
+import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
+import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
+import world.bentobox.challenges.panel.CommonPagedPanel;
+import world.bentobox.challenges.panel.CommonPanel;
+import world.bentobox.challenges.panel.ConversationUtils;
+import world.bentobox.challenges.panel.util.MultiEntitySelector;
+import world.bentobox.challenges.utils.Constants;
+import world.bentobox.challenges.utils.GuiUtils;
+import world.bentobox.challenges.utils.Utils;
+
+
+/**
+ * This class allows to edit entities that are in required entities map.
+ */
+public class ManageEntitiesPanel extends CommonPagedPanel
+{
+	private ManageEntitiesPanel(CommonPanel parentGUI, Map<EntityType, Integer> requiredEntities)
+	{
+		super(parentGUI);
+		this.requiredEntities = requiredEntities;
+
+		this.entityList = new ArrayList<>(this.requiredEntities.keySet());
+		this.entityList.sort(Comparator.comparing(Enum::name));
+
+		this.selectedEntities = new HashSet<>(EntityType.values().length);
+	}
+
+
+	/**
+	 * Open the Challenges Admin GUI.
+	 */
+	public static void open(CommonPanel parentGUI, Map<EntityType, Integer> requiredEntities)
+	{
+		new ManageEntitiesPanel(parentGUI, requiredEntities).build();
+	}
+
+
+// ---------------------------------------------------------------------
+// Section: Methods
+// ---------------------------------------------------------------------
+
+
+	/**
+	 * This method builds all necessary elements in GUI panel.
+	 */
+	@Override
+	public void build()
+	{
+		PanelBuilder panelBuilder = new PanelBuilder().user(this.user).
+			name(this.user.getTranslation(Constants.TITLE + "manage-entities"));
+
+		// create border
+		GuiUtils.fillBorder(panelBuilder);
+
+		panelBuilder.item(3, this.createButton(Button.ADD_ENTITY));
+		panelBuilder.item(5, this.createButton(Button.REMOVE_ENTITY));
+		panelBuilder.item(8, this.createButton(Button.SWITCH_ENTITY));
+
+		this.populateElements(panelBuilder,
+			this.entityList,
+			o -> this.createEntityButton((EntityType) o));
+
+		// Add return button.
+		panelBuilder.item(44, this.returnButton);
+
+		panelBuilder.build();
+	}
+
+
+	/**
+	 * This method creates PanelItem button of requested type.
+	 * @param button Button which must be created.
+	 * @return new PanelItem with requested functionality.
+	 */
+	private PanelItem createButton(Button button)
+	{
+		final String reference = Constants.BUTTON + button.name().toLowerCase() + ".";
+
+		final String name = this.user.getTranslation(reference + "name");
+		final List<String> description = new ArrayList<>(3);
+		description.add(this.user.getTranslation(reference + "description"));
+
+		ItemStack icon;
+		PanelItem.ClickHandler clickHandler;
+		boolean glow;
+
+		switch (button)
+		{
+			case ADD_ENTITY -> {
+				icon = new ItemStack(Material.BUCKET);
+				clickHandler = (panel, user1, clickType, slot) -> {
+					MultiEntitySelector.open(this.user,
+						this.asEggs,
+						MultiEntitySelector.Mode.ALIVE,
+						this.requiredEntities.keySet(),
+						(status, entities) -> {
+							if (status)
+							{
+								entities.forEach(entity -> {
+									this.requiredEntities.put(entity, 1);
+									this.entityList.add(entity);
+								});
+							}
+
+							this.build();
+						});
+					return true;
+				};
+				glow = false;
+
+				description.add("");
+				description.add(this.user.getTranslation(Constants.TIPS + "click-to-add"));
+			}
+			case REMOVE_ENTITY -> {
+
+				if (!this.selectedEntities.isEmpty())
+				{
+					description.add(this.user.getTranslation(reference + "title"));
+					this.selectedEntities.forEach(entity -> {
+						description.add(this.user.getTranslation(reference + "entity",
+							"[entity]", Utils.prettifyObject(entity, this.user)));
+					});
+				}
+
+				icon = new ItemStack(Material.LAVA_BUCKET);
+
+				clickHandler = (panel, user1, clickType, slot) ->
+				{
+					if (!this.selectedEntities.isEmpty())
+					{
+						this.requiredEntities.keySet().removeAll(this.selectedEntities);
+						this.entityList.removeAll(this.selectedEntities);
+						this.selectedEntities.clear();
+						this.build();
+					}
+
+					return true;
+				};
+
+				glow = !this.entityList.isEmpty();
+
+				description.add("");
+				description.add(this.user.getTranslation(Constants.TIPS + "click-to-remove"));
+			}
+			case SWITCH_ENTITY -> {
+				icon = new ItemStack(this.asEggs ? Material.EGG : Material.PLAYER_HEAD);
+
+				clickHandler = (panel, user1, clickType, slot) -> {
+					this.asEggs = !this.asEggs;
+					this.build();
+					return true;
+				};
+				glow = false;
+
+				description.add("");
+				description.add(this.user.getTranslation(Constants.TIPS + "click-to-toggle"));
+			}
+			default -> {
+				icon = new ItemStack(Material.PAPER);
+				clickHandler = null;
+				glow = false;
+			}
+		}
+
+		return new PanelItemBuilder().
+			icon(icon).
+			name(name).
+			description(description).
+			clickHandler(clickHandler).
+			glow(glow).
+			build();
+	}
+
+
+	/**
+	 * This method creates button for given entity.
+	 * @param entity Entity which button must be created.
+	 * @return new Button for entity.
+	 */
+	private PanelItem createEntityButton(EntityType entity)
+	{
+		final String reference = Constants.BUTTON + "entity.";
+
+		List<String> description = new ArrayList<>();
+
+		if (this.selectedEntities.contains(entity))
+		{
+			description.add(this.user.getTranslation(reference + "selected"));
+		}
+
+		description.add("");
+		description.add(this.user.getTranslation(Constants.TIPS + "left-click-to-choose"));
+
+		if (this.selectedEntities.contains(entity))
+		{
+			description.add(this.user.getTranslation(Constants.TIPS + "right-click-to-deselect"));
+		}
+		else
+		{
+			description.add(this.user.getTranslation(Constants.TIPS + "right-click-to-select"));
+		}
+
+		return new PanelItemBuilder().
+			name(this.user.getTranslation(reference + "name", "[entity]",
+				Utils.prettifyObject(entity, this.user))).
+			icon(this.asEggs ?
+				GuiUtils.getEntityEgg(entity, this.requiredEntities.get(entity)) :
+				GuiUtils.getEntityHead(entity, this.requiredEntities.get(entity))).
+			description(description).
+			clickHandler((panel, user1, clickType, slot) -> {
+				// On right click change which entities are selected for deletion.
+				if (clickType.isRightClick())
+				{
+					if (!this.selectedEntities.add(entity))
+					{
+						// Remove entity if it is already selected
+						this.selectedEntities.remove(entity);
+					}
+
+					this.build();
+				}
+				else
+				{
+					Consumer<Number> numberConsumer = number -> {
+						if (number != null)
+						{
+							this.requiredEntities.put(entity, number.intValue());
+						}
+
+						// reopen panel
+						this.build();
+					};
+
+					ConversationUtils.createNumericInput(numberConsumer,
+						this.user,
+						this.user.getTranslation(Constants.CONVERSATIONS + "input-number"),
+						1,
+						Integer.MAX_VALUE);
+				}
+				return true;
+			}).
+			glow(this.selectedEntities.contains(entity)).
+			build();
+	}
+
+
+// ---------------------------------------------------------------------
+// Section: Enums
+// ---------------------------------------------------------------------
+
+
+	/**
+	 * Functional buttons in current GUI.
+	 */
+	private enum Button
+	{
+		ADD_ENTITY,
+		REMOVE_ENTITY,
+		SWITCH_ENTITY
+	}
+
+
+// ---------------------------------------------------------------------
+// Section: Variables
+// ---------------------------------------------------------------------
+
+	/**
+	 * List with entities to avoid list irregularities.
+	 */
+	private final List<EntityType> entityList;
+
+	/**
+	 * Set with entities that are selected.
+	 */
+	private final Set<EntityType> selectedEntities;
+
+	/**
+	 * Map that contains all entities and their cound.
+	 */
+	private final Map<EntityType, Integer> requiredEntities;
+
+	/**
+	 * Boolean indicate if entities should be displayed as eggs or mob heads.
+	 */
+	private boolean asEggs;
+}

src/main/java/world/bentobox/challenges/panel/user/ChallengesGUI.java

@@ -1,528 +0,0 @@
-package world.bentobox.challenges.panel.user;
-
-
-import java.util.List;
-
-import org.bukkit.ChatColor;
-import org.bukkit.Material;
-import org.bukkit.World;
-import org.bukkit.inventory.ItemStack;
-
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.ChallengesAddon;
-import world.bentobox.challenges.managers.ChallengesManager;
-import world.bentobox.challenges.config.SettingsUtils.VisibilityMode;
-import world.bentobox.challenges.database.object.Challenge;
-import world.bentobox.challenges.panel.CommonGUI;
-import world.bentobox.challenges.tasks.TryToComplete;
-import world.bentobox.challenges.utils.GuiUtils;
-import world.bentobox.challenges.utils.LevelStatus;
-
-
-/**
- * This is UserGUI class. It contains everything necessary for user to use it.
- */
-public class ChallengesGUI extends CommonGUI
-{
-// ---------------------------------------------------------------------
-// Section: Constructors
-// ---------------------------------------------------------------------
-
-	/**
-	 * Default constructor that inits panels with minimal requirements, without parent panel.
-	 *
-	 * @param addon Addon where panel operates.
-	 * @param world World from which panel was created.
-	 * @param user User who created panel.
-	 * @param topLabel Command top label which creates panel (f.e. island or ai)
-	 * @param permissionPrefix Command permission prefix (f.e. bskyblock.)
-	 */
-	public ChallengesGUI(ChallengesAddon addon,
-		World world,
-		User user,
-		String topLabel,
-		String permissionPrefix)
-	{
-		super(addon, world, user, topLabel, permissionPrefix);
-		this.challengesManager = this.addon.getChallengesManager();
-
-		this.levelStatusList = this.challengesManager.getAllChallengeLevelStatus(this.user, this.world);
-
-		for (LevelStatus levelStatus : this.levelStatusList)
-		{
-			if (levelStatus.isUnlocked())
-			{
-				this.lastSelectedLevel = levelStatus;
-			}
-			else
-			{
-				break;
-			}
-		}
-
-		this.containsChallenges = this.challengesManager.hasAnyChallengeData(this.world);
-	}
-
-// ---------------------------------------------------------------------
-// Section: Methods
-// ---------------------------------------------------------------------
-
-
-	/**
-	 * This method builds all necessary elements in GUI panel.
-	 */
-	@Override
-	public void build()
-	{
-		// Do not open gui if there is no challenges.
-		if (!this.containsChallenges)
-		{
-			this.addon.logError("There are no challenges set up!");
-			this.user.sendMessage("challenges.errors.no-challenges");
-			return;
-		}
-
-		PanelBuilder panelBuilder = new PanelBuilder().user(this.user).
-			name(this.user.getTranslation("challenges.gui.title.challenges"));
-
-		// TODO: get last completed level.
-
-		int nextItemIndex = 0;
-
-		if (this.addon.getChallengesSettings().isFreeChallengesFirst())
-		{
-			this.addFreeChallenges(panelBuilder, nextItemIndex);
-
-			// Start new row for challenges.
-			if (panelBuilder.nextSlot() % 9 != 0)
-			{
-				nextItemIndex = panelBuilder.nextSlot() - panelBuilder.nextSlot() % 9 + 9;
-			}
-			else
-			{
-				nextItemIndex = panelBuilder.nextSlot();
-			}
-		}
-
-		this.addChallenges(panelBuilder, nextItemIndex);
-
-		// Start new row for levels.
-		// Start new row for challenges.
-		if (panelBuilder.nextSlot() % 9 != 0)
-		{
-			nextItemIndex = panelBuilder.nextSlot() - panelBuilder.nextSlot() % 9 + 9;
-		}
-		else
-		{
-			nextItemIndex = panelBuilder.nextSlot();
-		}
-
-		this.addChallengeLevels(panelBuilder, nextItemIndex);
-
-		if (!this.addon.getChallengesSettings().isFreeChallengesFirst())
-		{
-			// Start new row for free challenges.
-			if (panelBuilder.nextSlot() % 9 != 0)
-			{
-				nextItemIndex = panelBuilder.nextSlot() - panelBuilder.nextSlot() % 9 + 9;
-			}
-			else
-			{
-				nextItemIndex = panelBuilder.nextSlot();
-			}
-
-			this.addFreeChallenges(panelBuilder, nextItemIndex);
-		}
-
-		panelBuilder.build();
-	}
-
-
-	/**
-	 * This method adds free challenges to panelBuilder.
-	 * @param panelBuilder where free challenges must be added.
-	 * @param firstItemIndex index of first element.
-	 */
-	private void addFreeChallenges(PanelBuilder panelBuilder, int firstItemIndex)
-	{
-		List<Challenge> freeChallenges = this.challengesManager.getFreeChallenges(this.world);
-
-		if (this.addon.getChallengesSettings().isRemoveCompleteOneTimeChallenges())
-		{
-			freeChallenges.removeIf(challenge -> !challenge.isRepeatable() &&
-				this.challengesManager.isChallengeComplete(this.user, this.world, challenge));
-		}
-
-		// Remove all undeployed challenges if VisibilityMode is set to Hidden.
-		if (this.addon.getChallengesSettings().getVisibilityMode().equals(VisibilityMode.HIDDEN))
-		{
-			freeChallenges.removeIf(challenge -> !challenge.isDeployed());
-		}
-
-		final int freeChallengesCount = freeChallenges.size();
-
-		if (freeChallengesCount > 18)
-		{
-			int index = firstItemIndex;
-
-			if (this.freeChallengeIndex > 0)
-			{
-				panelBuilder.item(index++, new PanelItemBuilder().
-					icon(Material.OAK_SIGN).
-					name(this.user.getTranslation("challenges.gui.buttons.previous")).
-					clickHandler((panel, user1, clickType, slot) -> {
-						this.freeChallengeIndex--;
-						this.build();
-						return true;
-					}).build());
-			}
-
-			int currentIndex = this.freeChallengeIndex;
-
-			while (panelBuilder.nextSlot() != firstItemIndex + 18 && currentIndex < freeChallengesCount)
-			{
-				panelBuilder.item(index++, this.getChallengeButton(freeChallenges.get(currentIndex++)));
-			}
-
-			// Check if one challenge is left
-			if (currentIndex + 1 == freeChallengesCount)
-			{
-				panelBuilder.item(index, this.getChallengeButton(freeChallenges.get(currentIndex)));
-			}
-			else if (currentIndex < freeChallengesCount)
-			{
-				panelBuilder.item(index, new PanelItemBuilder().
-					icon(Material.OAK_SIGN).
-					name(this.user.getTranslation("challenges.gui.buttons.next")).
-					clickHandler((panel, user1, clickType, slot) -> {
-						this.freeChallengeIndex++;
-						this.build();
-						return true;
-					}).build());
-			}
-		}
-		else
-		{
-			for (Challenge challenge : freeChallenges)
-			{
-				// there are no limitations. Just bunch insert.
-				panelBuilder.item(firstItemIndex++, this.getChallengeButton(challenge));
-			}
-		}
-	}
-
-
-	/**
-	 * This method adds last selected level challenges to panelBuilder.
-	 * @param panelBuilder where last selected level challenges must be added.
-	 * @param firstItemIndex index of first element.
-	 */
-	private void addChallenges(PanelBuilder panelBuilder, int firstItemIndex)
-	{
-		if (this.lastSelectedLevel != null)
-		{
-			List<Challenge> challenges = this.challengesManager.getLevelChallenges(this.lastSelectedLevel.getLevel());
-
-			if (this.addon.getChallengesSettings().isRemoveCompleteOneTimeChallenges())
-			{
-				challenges.removeIf(challenge -> !challenge.isRepeatable() &&
-					this.challengesManager.isChallengeComplete(this.user, this.world, challenge));
-			}
-
-			// Remove all undeployed challenges if VisibilityMode is set to Hidden.
-			if (this.addon.getChallengesSettings().getVisibilityMode().equals(VisibilityMode.HIDDEN))
-			{
-				challenges.removeIf(challenge -> !challenge.isDeployed());
-			}
-
-			final int challengesCount = challenges.size();
-
-			if (challengesCount > 18)
-			{
-				int index = firstItemIndex;
-
-				if (this.pageIndex > 0)
-				{
-					panelBuilder.item(index++, new PanelItemBuilder().
-						icon(Material.OAK_SIGN).
-						name(this.user.getTranslation("challenges.gui.buttons.previous")).
-						clickHandler((panel, user1, clickType, slot) -> {
-							this.pageIndex--;
-							this.build();
-							return true;
-						}).build());
-				}
-
-				int currentIndex = this.pageIndex;
-
-				while (panelBuilder.nextSlot() != firstItemIndex + 18 && currentIndex < challengesCount)
-				{
-					panelBuilder.item(index++, this.getChallengeButton(challenges.get(currentIndex++)));
-				}
-
-				// Check if one challenge is left
-				if (currentIndex + 1 == challengesCount)
-				{
-					panelBuilder.item(index, this.getChallengeButton(challenges.get(currentIndex)));
-				}
-				else if (currentIndex < challengesCount)
-				{
-					panelBuilder.item(index, new PanelItemBuilder().
-						icon(Material.OAK_SIGN).
-						name(this.user.getTranslation("challenges.gui.buttons.next")).
-						clickHandler((panel, user1, clickType, slot) -> {
-							this.pageIndex++;
-							this.build();
-							return true;
-						}).build());
-				}
-			}
-			else
-			{
-				for (Challenge challenge : challenges)
-				{
-					// there are no limitations. Just bunch insert.
-					panelBuilder.item(firstItemIndex++, this.getChallengeButton(challenge));
-				}
-			}
-		}
-	}
-
-
-	/**
-	 * This method adds challenge levels to panelBuilder.
-	 * @param panelBuilder where challenge levels must be added.
-	 * @param firstItemIndex index of first element.
-	 */
-	private void addChallengeLevels(PanelBuilder panelBuilder, int firstItemIndex)
-	{
-		final int levelCounts = this.levelStatusList.size();
-
-		if (levelCounts > 9)
-		{
-			int index = firstItemIndex;
-
-			if (this.levelIndex > 0)
-			{
-				panelBuilder.item(index++, new PanelItemBuilder().
-					icon(Material.OAK_SIGN).
-					name(this.user.getTranslation("challenges.gui.buttons.previous")).
-					clickHandler((panel, user1, clickType, slot) -> {
-						this.levelIndex--;
-						this.build();
-						return true;
-					}).build());
-			}
-
-			int currentIndex = this.levelIndex;
-
-			while (panelBuilder.nextSlot() != firstItemIndex + 9 && currentIndex < levelCounts)
-			{
-				panelBuilder.item(index++, this.getLevelButton(this.levelStatusList.get(currentIndex++)));
-			}
-
-			// Check if one challenge is left
-			if (currentIndex + 1 == levelCounts)
-			{
-				panelBuilder.item(index, this.getLevelButton(this.levelStatusList.get(currentIndex)));
-			}
-			else if (currentIndex < levelCounts)
-			{
-				panelBuilder.item(index, new PanelItemBuilder().
-					icon(Material.OAK_SIGN).
-					name(this.user.getTranslation("challenges.gui.buttons.next")).
-					clickHandler((panel, user1, clickType, slot) -> {
-						this.levelIndex++;
-						this.build();
-						return true;
-					}).build());
-			}
-		}
-		else
-		{
-			for (LevelStatus level : this.levelStatusList)
-			{
-				// there are no limitations. Just bunch insert.
-				panelBuilder.item(firstItemIndex++, this.getLevelButton(level));
-			}
-		}
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Icon building
-// ---------------------------------------------------------------------
-
-
-	/**
-	 * This method creates given challenges icon that on press tries to complete it.
-	 * @param challenge which icon must be constructed.
-	 * @return PanelItem icon for challenge.
-	 */
-	private PanelItem getChallengeButton(Challenge challenge)
-	{
-		return new PanelItemBuilder().
-			icon(challenge.getIcon()).
-			name(challenge.getFriendlyName().isEmpty() ?
-				challenge.getUniqueId() :
-				ChatColor.translateAlternateColorCodes('&', challenge.getFriendlyName())).
-			description(GuiUtils.stringSplit(this.generateChallengeDescription(challenge, this.user.getPlayer()),
-				this.addon.getChallengesSettings().getLoreLineLength())).
-			clickHandler((panel, user1, clickType, slot) -> {
-
-				// Add ability to input how many repeats player should do.
-				// Do not open if challenge is not repeatable.
-
-				if (clickType.isRightClick() &&
-					challenge.isRepeatable() &&
-					this.user.hasPermission(this.permissionPrefix + "challenges.multiple"))
-				{
-					new MultipleGUI(this.user,
-						this.addon.getChallengesSettings().getLoreLineLength(),
-						value -> {
-							TryToComplete.complete(this.addon,
-								this.user,
-								challenge,
-								this.world,
-								this.topLabel,
-								this.permissionPrefix,
-								value);
-
-							this.build();
-						});
-				}
-				else
-				{
-					if (TryToComplete.complete(this.addon,
-						this.user,
-						challenge,
-						this.world,
-						this.topLabel,
-						this.permissionPrefix))
-					{
-						panel.getInventory().setItem(slot, this.getChallengeButton(challenge).getItem());
-					}
-				}
-
-				return true;
-			}).
-			glow(this.addon.getChallengesSettings().isAddCompletedGlow() &&
-				this.challengesManager.isChallengeComplete(this.user, this.world, challenge)).
-			build();
-	}
-
-
-	/**
-	 * This method creates button for given level.
-	 * @param level which button must be created.
-	 * @return Button for given level.
-	 */
-	private PanelItem getLevelButton(LevelStatus level)
-	{
-		// Create a nice name for the level
-		String name = level.getLevel().getFriendlyName().isEmpty() ?
-			level.getLevel().getUniqueId() :
-			level.getLevel().getFriendlyName();
-
-		ItemStack icon;
-		List<String> description;
-		PanelItem.ClickHandler clickHandler;
-		boolean glow;
-
-		if (level == this.lastSelectedLevel)
-		{
-			icon = level.getLevel().getIcon();
-			description = GuiUtils.stringSplit(
-				this.generateLevelDescription(level.getLevel(), user.getPlayer()),
-				this.addon.getChallengesSettings().getLoreLineLength());
-			clickHandler = null;
-			glow = true;
-		}
-		else if (level.isUnlocked())
-		{
-			icon = level.getLevel().getIcon();
-			description = GuiUtils.stringSplit(
-				this.generateLevelDescription(level.getLevel(), user.getPlayer()),
-				this.addon.getChallengesSettings().getLoreLineLength());
-			clickHandler = (panel, user1, clickType, slot) -> {
-				this.lastSelectedLevel = level;
-
-				// Reset page index for challenges.
-				this.pageIndex = 0;
-
-				this.build();
-				return true;
-			};
-			glow = this.addon.getChallengesSettings().isAddCompletedGlow() &&
-				this.challengesManager.isLevelCompleted(this.user, this.world, level.getLevel());
-		}
-		else
-		{
-			if (level.getLevel().getLockedIcon() != null)
-			{
-				// Clone will prevent issues with description storing.
-				// It can be done only here as it can be null.
-				icon = level.getLevel().getLockedIcon().clone();
-			}
-			else
-			{
-				icon = this.addon.getChallengesSettings().getLockedLevelIcon();
-			}
-
-			description = GuiUtils.stringSplit(
-				this.user.getTranslation("challenges.gui.descriptions.level-locked",
-					"[count]", Integer.toString(level.getNumberOfChallengesStillToDo()),
-					"[level]", level.getPreviousLevel().getFriendlyName()),
-				this.addon.getChallengesSettings().getLoreLineLength());
-
-			clickHandler = null;
-			glow = false;
-		}
-
-		return new PanelItemBuilder().
-			icon(icon).
-			name(ChatColor.translateAlternateColorCodes('&', name)).
-			description(description).
-			glow(glow).
-			clickHandler(clickHandler).
-			build();
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Variables
-// ---------------------------------------------------------------------
-
-	/**
-	 * This will be used if free challenges are more then 18.
-	 */
-	private int freeChallengeIndex = 0;
-
-	/**
-	 * This will be used if levels are more then 9.
-	 */
-	private int levelIndex;
-
-	/**
-	 * This list contains all information about level completion in current world.
-	 */
-	private List<LevelStatus> levelStatusList;
-
-	/**
-	 * This indicate last selected level.
-	 */
-	private LevelStatus lastSelectedLevel;
-
-	/**
-	 * Challenge Manager object.
-	 */
-	private ChallengesManager challengesManager;
-
-	/**
-	 * This boolean indicates if in the world there exist challenges for displaying in GUI.
-	 */
-	private final boolean containsChallenges;
-}

src/main/java/world/bentobox/challenges/panel/user/MultipleGUI.java

@@ -1,215 +0,0 @@
-
-package world.bentobox.challenges.panel.user;
-
-import java.util.function.Consumer;
-
-import org.bukkit.Material;
-import org.bukkit.inventory.ItemStack;
-
-import world.bentobox.bentobox.api.panels.Panel;
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.utils.GuiUtils;
-
-
-/**
- * This GUI will pop out when user uses right click on challenge. It is meant to choose
- * how many times player will complete challenges.
- */
-public class MultipleGUI
-{
-	/**
-	 * Default constructor.
-	 * @param user User who opens gui.
-	 * @param lineLength Length of lore message.
-	 * @param action Action that will be performed on value clicking.
-	 */
-	public MultipleGUI(User user, int lineLength, Consumer<Integer> action)
-	{
-		this.user = user;
-		this.lineLength = lineLength;
-		this.action = action;
-
-		this.build();
-	}
-
-	/**
-	 * This method builds panel that allows to change given number value.
-	 */
-	private void build()
-	{
-		PanelBuilder panelBuilder = new PanelBuilder().
-			user(this.user).
-			type(Panel.Type.HOPPER).
-			name(this.user.getTranslation("challenges.gui.title.multiple-complete"));
-
-		panelBuilder.item(2, this.getButton(Button.VALUE));
-
-		// Reduce
-		panelBuilder.item(0, this.getButton(Button.REDUCE_LOT));
-		panelBuilder.item(1, this.getButton(Button.REDUCE));
-
-		// Increase
-		panelBuilder.item(3, this.getButton(Button.INCREASE));
-		panelBuilder.item(4, this.getButton(Button.INCREASE_LOT));
-
-		panelBuilder.build();
-	}
-
-
-	/**
-	 * This method creates PanelItem with required functionality.
-	 * @param button Functionality requirement.
-	 * @return PanelItem with functionality.
-	 */
-	private PanelItem getButton(Button button)
-	{
-		ItemStack icon;
-		String name;
-		String description;
-		PanelItem.ClickHandler clickHandler;
-		boolean glow;
-
-		switch (button)
-		{
-			case VALUE:
-			{
-				name = this.user.getTranslation("challenges.gui.buttons.value");
-				description = this.user.getTranslation("challenges.gui.descriptions.current-value", "[value]", Integer.toString(this.value));
-				icon = new ItemStack(Material.GREEN_STAINED_GLASS_PANE);
-				clickHandler = (panel, user, clickType, slot) -> {
-					this.action.accept(this.value);
-					return true;
-				};
-				glow = false;
-				break;
-			}
-			case INCREASE:
-			{
-				name = this.user.getTranslation("challenges.gui.buttons.increase");
-				description = this.user.getTranslation("challenges.gui.descriptions.increase-by", "[value]", "1");
-				icon = new ItemStack(Material.BLUE_STAINED_GLASS_PANE);
-				clickHandler = (panel, user, clickType, slot) -> {
-					this.value++;
-					// Necessary just to update second item
-					panel.getInventory().setItem(2, this.getButton(Button.VALUE).getItem());
-					return true;
-				};
-				glow = false;
-				break;
-			}
-			case INCREASE_LOT:
-			{
-				name = this.user.getTranslation("challenges.gui.buttons.increase");
-				description = this.user.getTranslation("challenges.gui.descriptions.increase-by", "[value]", "5");
-				icon = new ItemStack(Material.MAGENTA_STAINED_GLASS_PANE);
-				clickHandler = (panel, user, clickType, slot) -> {
-					this.value += 5;
-					// Necessary just to update second item
-					panel.getInventory().setItem(2, this.getButton(Button.VALUE).getItem());
-					return true;
-				};
-				glow = false;
-				break;
-			}
-			case REDUCE:
-			{
-				name = this.user.getTranslation("challenges.gui.buttons.reduce");
-				description = this.user.getTranslation("challenges.gui.descriptions.reduce-by", "[value]", "1");
-				icon = new ItemStack(Material.ORANGE_STAINED_GLASS_PANE);
-				clickHandler = (panel, user, clickType, slot) -> {
-					this.value--;
-
-					if (this.value < 1)
-					{
-						this.value = 1;
-					}
-
-					// Necessary just to update second item
-					panel.getInventory().setItem(2, this.getButton(Button.VALUE).getItem());
-
-					return true;
-				};
-				glow = false;
-				break;
-			}
-			case REDUCE_LOT:
-			{
-				name = this.user.getTranslation("challenges.gui.buttons.reduce");
-				description = this.user.getTranslation("challenges.gui.descriptions.reduce-by", "[value]", "5");
-				icon = new ItemStack(Material.RED_STAINED_GLASS_PANE);
-				clickHandler = (panel, user, clickType, slot) -> {
-					this.value -= 5;
-
-					if (this.value < 1)
-					{
-						this.value = 1;
-					}
-
-					// Necessary just to update second item
-					panel.getInventory().setItem(2, this.getButton(Button.VALUE).getItem());
-
-					return true;
-				};
-				glow = false;
-				break;
-			}
-			default:
-				return null;
-		}
-
-		return new PanelItemBuilder().
-			icon(icon).
-			name(name).
-			description(GuiUtils.stringSplit(description, this.lineLength)).
-			glow(glow).
-			clickHandler(clickHandler).
-			build();
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Enums
-// ---------------------------------------------------------------------
-
-
-	/**
-	 * This enum allows to easier define available buttons.
-	 */
-	enum Button
-	{
-		VALUE,
-		REDUCE,
-		REDUCE_LOT,
-		INCREASE,
-		INCREASE_LOT
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Instance variables
-// ---------------------------------------------------------------------
-
-
-	/**
-	 * This variable allows to access to user object.
-	 */
-	private User user;
-
-	/**
-	 * This variable holds action that will be performed on accept.
-	 */
-	private Consumer<Integer> action;
-
-	/**
-	 * This variable holds a number of characters in single line for lore message.
-	 */
-	private int lineLength;
-
-	/**
-	 * This integer holds current value of completion count.
-	 */
-	private int value = 1;
-}

src/main/java/world/bentobox/challenges/panel/util/ConfirmationGUI.java

@@ -1,114 +0,0 @@
-package world.bentobox.challenges.panel.util;
-
-
-import java.util.function.Consumer;
-
-import org.bukkit.Material;
-
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.utils.GuiUtils;
-
-
-/**
- * This GUI is used to confirm that user wants to run command, that should be created from
- * command string list.
- */
-public class ConfirmationGUI
-{
-	/**
-	 * This constructor inits and opens ConfirmationGUI.
-	 *
-	 * @param user Gui Caller.
-	 */
-	public ConfirmationGUI(User user, Consumer<Boolean> consumer)
-	{
-		this.user = user;
-		this.consumer = consumer;
-
-		this.build();
-	}
-
-
-	/**
-	 * This method builds confirmation panel with 2 buttons.
-	 */
-	public void build()
-	{
-		PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(this.user.getTranslation("challenges.gui.title.admin.confirm-title"));
-
-		GuiUtils.fillBorder(panelBuilder, Material.BLUE_STAINED_GLASS_PANE);
-
-		// Accept buttons
-		panelBuilder.item(10, this.getButton(true));
-		panelBuilder.item(11, this.getButton(true));
-		panelBuilder.item(12, this.getButton(true));
-
-		panelBuilder.item(19, this.getButton(true));
-		panelBuilder.item(20, this.getButton(true));
-		panelBuilder.item(21, this.getButton(true));
-
-		panelBuilder.item(28, this.getButton(true));
-		panelBuilder.item(29, this.getButton(true));
-		panelBuilder.item(30, this.getButton(true));
-
-		// Cancel Buttons
-		panelBuilder.item(14, this.getButton(false));
-		panelBuilder.item(15, this.getButton(false));
-		panelBuilder.item(16, this.getButton(false));
-
-		panelBuilder.item(23, this.getButton(false));
-		panelBuilder.item(24, this.getButton(false));
-		panelBuilder.item(25, this.getButton(false));
-
-		panelBuilder.item(32, this.getButton(false));
-		panelBuilder.item(33, this.getButton(false));
-		panelBuilder.item(34, this.getButton(false));
-
-		panelBuilder.item(44,
-			new PanelItemBuilder().
-				icon(Material.OAK_DOOR).
-				name(this.user.getTranslation("challenges.gui.buttons.return")).
-				clickHandler( (panel, user1, clickType, slot) -> {
-					this.consumer.accept(false);
-					return true;
-				}).build());
-
-		panelBuilder.build();
-	}
-
-
-	/**
-	 * This method creates button with requested value.
-	 * @param returnValue requested value
-	 * @return PanelItem button.
-	 */
-	private PanelItem getButton(boolean returnValue)
-	{
-		return new PanelItemBuilder().
-			name(this.user.getTranslation("challenges.gui.buttons.admin." + (returnValue ? "accept" : "cancel"))).
-			icon(returnValue ? Material.GREEN_STAINED_GLASS_PANE : Material.RED_STAINED_GLASS_PANE).
-			clickHandler((panel, user1, clickType, i) -> {
-				this.consumer.accept(returnValue);
-				return true;
-			}).
-			build();
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Variables
-// ---------------------------------------------------------------------
-
-	/**
-	 * User who wants to run command.
-	 */
-	private User user;
-
-	/**
-	 * Stores current Consumer
-	 */
-	private Consumer<Boolean> consumer;
-}

src/main/java/world/bentobox/challenges/panel/util/NumberGUI.java

@@ -1,559 +0,0 @@
-package world.bentobox.challenges.panel.util;
-
-
-import java.util.function.BiConsumer;
-import java.util.function.Consumer;
-
-import org.bukkit.Material;
-import org.bukkit.conversations.Conversation;
-import org.bukkit.conversations.ConversationContext;
-import org.bukkit.conversations.ConversationFactory;
-import org.bukkit.conversations.NumericPrompt;
-import org.bukkit.conversations.Prompt;
-import org.bukkit.inventory.ItemStack;
-import org.eclipse.jdt.annotation.NonNull;
-
-import world.bentobox.bentobox.BentoBox;
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.utils.GuiUtils;
-
-
-/**
- * This gui allows to change current number and returns it to previous GUI
- */
-public class NumberGUI
-{
-    public NumberGUI(User user, int value, int lineLength, BiConsumer<Boolean, Integer> consumer)
-    {
-        this(user, value, Integer.MIN_VALUE, Integer.MAX_VALUE, lineLength, consumer);
-    }
-
-
-    public NumberGUI(User user, int value, int minValue, int lineLength, BiConsumer<Boolean, Integer> consumer)
-    {
-        this(user, value, minValue, Integer.MAX_VALUE, lineLength, consumer);
-    }
-
-
-    public NumberGUI(User user, int value, int minValue, int maxValue, int lineLength, BiConsumer<Boolean, Integer> consumer)
-    {
-        this.user = user;
-        this.value = value;
-        this.consumer = consumer;
-
-        this.minValue = minValue;
-        this.maxValue = maxValue;
-
-        this.currentOperation = Button.SET;
-
-        this.lineLength = lineLength;
-
-        this.build();
-    }
-
-
-    /**
-     * This method builds panel that allows to change given number value.
-     */
-    private void build()
-    {
-        PanelBuilder panelBuilder = new PanelBuilder().user(this.user).name(this.user.getTranslation("challenges.gui.title.admin.manage-numbers"));
-
-        GuiUtils.fillBorder(panelBuilder);
-
-        // Others
-        panelBuilder.item(1, this.getButton(Button.SAVE));
-
-        panelBuilder.item(19, this.getButton(Button.VALUE));
-        panelBuilder.item(44, this.getButton(Button.CANCEL));
-
-        panelBuilder.item(2, this.getButton(Button.INPUT));
-
-        // operations
-        panelBuilder.item(3, this.getButton(Button.SET));
-        panelBuilder.item(4, this.getButton(Button.INCREASE));
-        panelBuilder.item(5, this.getButton(Button.REDUCE));
-        panelBuilder.item(6, this.getButton(Button.MULTIPLY));
-
-        // Numbers
-        panelBuilder.item(11, this.createNumberButton(1));
-        panelBuilder.item(12, this.createNumberButton(10));
-        panelBuilder.item(13, this.createNumberButton(100));
-        panelBuilder.item(14, this.createNumberButton(1000));
-        panelBuilder.item(15, this.createNumberButton(10000));
-
-        panelBuilder.item(20, this.createNumberButton(2));
-        panelBuilder.item(21, this.createNumberButton(20));
-        panelBuilder.item(22, this.createNumberButton(200));
-        panelBuilder.item(23, this.createNumberButton(2000));
-        panelBuilder.item(24, this.createNumberButton(20000));
-
-        panelBuilder.item(29, this.createNumberButton(5));
-        panelBuilder.item(30, this.createNumberButton(50));
-        panelBuilder.item(31, this.createNumberButton(500));
-        panelBuilder.item(32, this.createNumberButton(5000));
-        panelBuilder.item(33, this.createNumberButton(50000));
-
-        panelBuilder.build();
-    }
-
-
-    /**
-     * This method creates PanelItem with required functionality.
-     * @param button Functionality requirement.
-     * @return PanelItem with functionality.
-     */
-    private PanelItem getButton(Button button)
-    {
-        ItemStack icon;
-        String name;
-        String description;
-        PanelItem.ClickHandler clickHandler;
-        boolean glow;
-
-        switch (button)
-        {
-        case SAVE:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.save");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.save");
-            icon = new ItemStack(Material.COMMAND_BLOCK);
-            clickHandler = (panel, user, clickType, slot) -> {
-                this.consumer.accept(true, this.value);
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case CANCEL:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.cancel");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.cancel");
-            icon = new ItemStack(Material.OAK_DOOR);
-            clickHandler = (panel, user, clickType, slot) -> {
-                this.consumer.accept(false, this.value);
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case INPUT:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.input");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.input");
-            icon = new ItemStack(Material.ANVIL);
-            clickHandler = (panel, user, clickType, slot) -> {
-
-                this.getNumberInput(number -> {
-                    if (number != null)
-                    {
-                        // Null value is passed if user write cancel.
-                        this.value = number.intValue();
-                    }
-
-                    this.build();
-                },
-                        this.user.getTranslation("challenges.gui.questions.admin.number"));
-
-                return true;
-            };
-            glow = false;
-            break;
-        }
-        case VALUE:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.value");
-            description = this.user.getTranslation("challenges.gui.descriptions.current-value", "[value]", Integer.toString(this.value));
-            icon = new ItemStack(Material.PAPER);
-            clickHandler = (panel, user, clickType, slot) -> true;
-            glow = false;
-            break;
-        }
-        case SET:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.set");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.set");
-            icon = new ItemStack(Material.WHITE_STAINED_GLASS_PANE);
-            clickHandler = (panel, user, clickType, slot) -> {
-                this.currentOperation = Button.SET;
-                this.build();
-                return true;
-            };
-            glow = this.currentOperation.equals(Button.SET);
-            break;
-        }
-        case INCREASE:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.increase");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.increase");
-            icon = new ItemStack(Material.GREEN_STAINED_GLASS_PANE);
-            clickHandler = (panel, user, clickType, slot) -> {
-                this.currentOperation = Button.INCREASE;
-                this.build();
-                return true;
-            };
-            glow = this.currentOperation.equals(Button.INCREASE);
-            break;
-        }
-        case REDUCE:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.reduce");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.reduce");
-            icon = new ItemStack(Material.RED_STAINED_GLASS_PANE);
-            clickHandler = (panel, user, clickType, slot) -> {
-                this.currentOperation = Button.REDUCE;
-                this.build();
-                return true;
-            };
-            glow = this.currentOperation.equals(Button.REDUCE);
-            break;
-        }
-        case MULTIPLY:
-        {
-            name = this.user.getTranslation("challenges.gui.buttons.admin.multiply");
-            description = this.user.getTranslation("challenges.gui.descriptions.admin.multiply");
-            icon = new ItemStack(Material.BLUE_STAINED_GLASS_PANE);
-            clickHandler = (panel, user, clickType, slot) -> {
-                this.currentOperation = Button.MULTIPLY;
-                this.build();
-                return true;
-            };
-            glow = this.currentOperation.equals(Button.MULTIPLY);
-            break;
-        }
-        default:
-            return null;
-        }
-
-        return new PanelItemBuilder().
-                icon(icon).
-                name(name).
-                description(GuiUtils.stringSplit(description, this.lineLength)).
-                glow(glow).
-                clickHandler(clickHandler).
-                build();
-    }
-
-
-    /**
-     * This method creates Number Button based on input number.
-     * @param number Number which button must be created.
-     * @return PanelItem that represents number button.
-     */
-    private PanelItem createNumberButton(int number)
-    {
-        PanelItemBuilder itemBuilder = new PanelItemBuilder();
-
-        switch (this.currentOperation)
-        {
-        case SET:
-        {
-            itemBuilder.name(this.user.getTranslation("challenges.gui.buttons.admin.number","[number]", Integer.toString(number)));
-            itemBuilder.icon(Material.WHITE_STAINED_GLASS_PANE);
-            itemBuilder.clickHandler((panel, user1, clickType, i) -> {
-                this.value = number;
-
-                if (this.value > this.maxValue)
-                {
-                    this.user.sendMessage("challenges.errors.not-valid-integer",
-                            "[value]", Integer.toString(this.value),
-                            "[min]", Integer.toString(this.minValue),
-                            "[max]", Integer.toString(this.maxValue));
-
-                    this.value = this.maxValue;
-                }
-
-                if (this.value < this.minValue)
-                {
-                    this.user.sendMessage("challenges.errors.not-valid-integer",
-                            "[value]", Integer.toString(this.value),
-                            "[min]", Integer.toString(this.minValue),
-                            "[max]", Integer.toString(this.maxValue));
-
-                    this.value = this.minValue;
-                }
-
-                this.build();
-                return true;
-            });
-
-            break;
-        }
-        case INCREASE:
-        {
-            itemBuilder.name(this.user.getTranslation("challenges.gui.buttons.admin.number","[number]", Integer.toString(number)));
-            itemBuilder.icon(Material.GREEN_STAINED_GLASS_PANE);
-            itemBuilder.clickHandler((panel, user1, clickType, i) -> {
-                this.value += number;
-
-                if (this.value > this.maxValue)
-                {
-                    this.user.sendMessage("challenges.errors.not-valid-integer",
-                            "[value]", Integer.toString(this.value),
-                            "[min]", Integer.toString(this.minValue),
-                            "[max]", Integer.toString(this.maxValue));
-
-                    this.value = this.maxValue;
-                }
-
-                this.build();
-                return true;
-            });
-
-            break;
-        }
-        case REDUCE:
-        {
-            itemBuilder.name(this.user.getTranslation("challenges.gui.buttons.admin.number","[number]", Integer.toString(number)));
-            itemBuilder.icon(Material.RED_STAINED_GLASS_PANE);
-            itemBuilder.clickHandler((panel, user1, clickType, i) -> {
-                this.value -= number;
-
-                if (this.value < this.minValue)
-                {
-                    this.user.sendMessage("challenges.errors.not-valid-integer",
-                            "[value]", Integer.toString(this.value),
-                            "[min]", Integer.toString(this.minValue),
-                            "[max]", Integer.toString(this.maxValue));
-
-                    this.value = this.minValue;
-                }
-
-                this.build();
-                return true;
-            });
-
-            break;
-        }
-        case MULTIPLY:
-        {
-            itemBuilder.name(this.user.getTranslation("challenges.gui.buttons.admin.number","[number]", Integer.toString(number)));
-            itemBuilder.icon(Material.BLUE_STAINED_GLASS_PANE);
-            itemBuilder.clickHandler((panel, user1, clickType, i) -> {
-                this.value *= number;
-
-                if (this.value > this.maxValue)
-                {
-                    this.user.sendMessage("challenges.errors.not-valid-integer",
-                            "[value]", Integer.toString(this.value),
-                            "[min]", Integer.toString(this.minValue),
-                            "[max]", Integer.toString(this.maxValue));
-
-                    this.value = this.maxValue;
-                }
-
-                this.build();
-                return true;
-            });
-
-            break;
-        }
-        default:
-            break;
-        }
-
-        return itemBuilder.build();
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Conversation
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * This method will close opened gui and writes inputText in chat. After players answers on
-     * inputText in chat, message will trigger consumer and gui will reopen.
-     * @param consumer Consumer that accepts player output text.
-     * @param question Message that will be displayed in chat when player triggers conversion.
-     */
-    private void getNumberInput(Consumer<Number> consumer, @NonNull String question)
-    {
-        final User user = this.user;
-
-        Conversation conversation =
-            new ConversationFactory(BentoBox.getInstance()).withFirstPrompt(
-                new NumericPrompt()
-                {
-                    /**
-                     * Override this method to perform some action with
-                     * the user's integer response.
-                     *
-                     * @param context Context information about the
-                     * conversation.
-                     * @param input The user's response as a {@link
-                     * Number}.
-                     * @return The next {@link Prompt} in the prompt
-                     * graph.
-                     */
-                    @Override
-                    protected Prompt acceptValidatedInput(ConversationContext context, Number input)
-                    {
-                        // Add answer to consumer.
-                        consumer.accept(input);
-                        // Reopen GUI
-                        NumberGUI.this.build();
-                        // End conversation
-                        return Prompt.END_OF_CONVERSATION;
-                    }
-
-
-                    /**
-                     * Override this method to do further validation on
-                     * the numeric player input after the input has been
-                     * determined to actually be a number.
-                     *
-                     * @param context Context information about the
-                     * conversation.
-                     * @param input The number the player provided.
-                     * @return The validity of the player's input.
-                     */
-                    @Override
-                    protected boolean isNumberValid(ConversationContext context, Number input)
-                    {
-                        return input.intValue() >= NumberGUI.this.minValue &&
-                            input.intValue() <= NumberGUI.this.maxValue;
-                    }
-
-
-                    /**
-                     * Optionally override this method to display an
-                     * additional message if the user enters an invalid
-                     * number.
-                     *
-                     * @param context Context information about the
-                     * conversation.
-                     * @param invalidInput The invalid input provided by
-                     * the user.
-                     * @return A message explaining how to correct the
-                     * input.
-                     */
-                    @Override
-                    protected String getInputNotNumericText(ConversationContext context,
-                        String invalidInput)
-                    {
-                        return NumberGUI.this.user
-                            .getTranslation("challenges.errors.not-a-integer", "[value]", invalidInput);
-                    }
-
-
-                    /**
-                     * Optionally override this method to display an
-                     * additional message if the user enters an invalid
-                     * numeric input.
-                     *
-                     * @param context Context information about the
-                     * conversation.
-                     * @param invalidInput The invalid input provided by
-                     * the user.
-                     * @return A message explaining how to correct the
-                     * input.
-                     */
-                    @Override
-                    protected String getFailedValidationText(ConversationContext context,
-                        Number invalidInput)
-                    {
-                        return NumberGUI.this.user.getTranslation("challenges.errors.not-valid-integer",
-                            "[value]", invalidInput.toString(),
-                            "[min]", Integer.toString(NumberGUI.this.minValue),
-                            "[max]", Integer.toString(NumberGUI.this.maxValue));
-                    }
-
-
-                    /**
-                     * @see Prompt#getPromptText(ConversationContext)
-                     */
-                    @Override
-                    public String getPromptText(ConversationContext conversationContext)
-                    {
-                        // Close input GUI.
-                        user.closeInventory();
-
-                        // There are no editable message. Just return question.
-                        return question;
-                    }
-                }).
-                withLocalEcho(false).
-                // On cancel conversation will be closed.
-                withEscapeSequence("cancel").
-                // Use null value in consumer to detect if user has abandoned conversation.
-                addConversationAbandonedListener(abandonedEvent ->
-                {
-                    if (!abandonedEvent.gracefulExit())
-                    {
-                        consumer.accept(null);
-                    }
-                }).
-                withPrefix(context ->
-                    NumberGUI.this.user.getTranslation("challenges.gui.questions.prefix")).
-                buildConversation(user.getPlayer());
-
-        conversation.begin();
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Enums
-    // ---------------------------------------------------------------------
-
-
-    /**
-     * This enum contains all button types.
-     */
-    private enum Button
-    {
-        SAVE,
-        CANCEL,
-        INPUT,
-
-        VALUE,
-
-        SET,
-        INCREASE,
-        REDUCE,
-        MULTIPLY
-    }
-
-
-    // ---------------------------------------------------------------------
-    // Section: Variables
-    // ---------------------------------------------------------------------
-
-    /**
-     * This variable stores current GUI consumer.
-     */
-    private BiConsumer<Boolean, Integer> consumer;
-
-    /**
-     * User who runs GUI.
-     */
-    private User user;
-
-    /**
-     * Current value.
-     */
-    private int value;
-
-    /**
-     * Minimal value that is allowed to set.
-     */
-    private int minValue;
-
-    /**
-     * Maximal value that is allowed to set.
-     */
-    private int maxValue;
-
-    /**
-     * This variable holds which operation now is processed.
-     */
-    private Button currentOperation;
-
-    /**
-     * This variable stores how large line can be, before warp it.
-     */
-    private int lineLength;
-}

src/main/java/world/bentobox/challenges/panel/util/StringListGUI.java

@@ -1,366 +0,0 @@
-package world.bentobox.challenges.panel.util;
-
-
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
-import java.util.function.BiConsumer;
-import java.util.function.Consumer;
-
-import org.bukkit.Material;
-import org.bukkit.conversations.Conversation;
-import org.bukkit.conversations.ConversationContext;
-import org.bukkit.conversations.ConversationFactory;
-import org.bukkit.conversations.Prompt;
-import org.bukkit.conversations.StringPrompt;
-import org.bukkit.inventory.ItemStack;
-import org.eclipse.jdt.annotation.NonNull;
-import org.eclipse.jdt.annotation.Nullable;
-
-import net.md_5.bungee.api.chat.ClickEvent;
-import net.md_5.bungee.api.chat.TextComponent;
-import world.bentobox.bentobox.BentoBox;
-import world.bentobox.bentobox.api.panels.PanelItem;
-import world.bentobox.bentobox.api.panels.builders.PanelBuilder;
-import world.bentobox.bentobox.api.panels.builders.PanelItemBuilder;
-import world.bentobox.bentobox.api.user.User;
-import world.bentobox.challenges.utils.GuiUtils;
-
-
-/**
- * This GUI allows to edit List of strings. AnvilGUI has limited text space, so splitting
- * text in multiple rows allows to edit each row separately.
- */
-public class StringListGUI
-{
-	public StringListGUI(User user, String value, int lineLength, BiConsumer<Boolean, List<String>> consumer)
-	{
-		this(user, Collections.singleton(value), lineLength, consumer);
-	}
-
-
-	public StringListGUI(User user, Collection<String> value, int lineLength, BiConsumer<Boolean, List<String>> consumer)
-	{
-		this(user, new ArrayList<>(value), lineLength, consumer);
-	}
-
-
-	public StringListGUI(User user, List<String> value, int lineLength, BiConsumer<Boolean, List<String>> consumer)
-	{
-		this.consumer = consumer;
-		this.user = user;
-		this.value = value;
-		this.lineLength = lineLength;
-
-		if (this.value.size() > 21)
-		{
-			// TODO: throw error that so large list cannot be edited.
-			this.consumer.accept(false, this.value);
-		}
-		else
-		{
-			this.build();
-		}
-	}
-
-
-	/**
-	 * This method builds panel that allows to change given string value.
-	 */
-	private void build()
-	{
-		PanelBuilder panelBuilder = new PanelBuilder().user(this.user).
-			name(this.user.getTranslation("challenges.gui.title.admin.edit-text-fields"));
-
-		GuiUtils.fillBorder(panelBuilder, Material.BLACK_STAINED_GLASS_PANE);
-
-		panelBuilder.item(1, this.getButton(Button.SAVE));
-		panelBuilder.item(2, this.getButton(Button.VALUE));
-
-		panelBuilder.item(4, this.getButton(Button.ADD));
-		panelBuilder.item(5, this.getButton(Button.REMOVE));
-		panelBuilder.item(6, this.getButton(Button.CLEAR));
-
-		panelBuilder.item(44, this.getButton(Button.CANCEL));
-
-		int slot = 10;
-
-		for (int stringIndex = 0; stringIndex < this.value.size() && slot < 36; stringIndex++)
-		{
-			if (!panelBuilder.slotOccupied(slot))
-			{
-				panelBuilder.item(slot,
-					this.createStringElement(this.value.get(stringIndex), stringIndex));
-			}
-
-			slot++;
-		}
-
-		panelBuilder.build();
-	}
-
-
-	/**
-	 * This method create button that does some functionality in current gui.
-	 * @param button Button functionality.
-	 * @return PanelItem.
-	 */
-	private PanelItem getButton(Button button)
-	{
-		ItemStack icon;
-		String name;
-		List<String> description;
-		PanelItem.ClickHandler clickHandler;
-
-		switch (button)
-		{
-			case SAVE:
-			{
-				name = this.user.getTranslation("challenges.gui.buttons.admin.save");
-				description = Collections.singletonList(this.user.getTranslation("challenges.gui.descriptions.admin.save"));
-				icon = new ItemStack(Material.GREEN_STAINED_GLASS_PANE);
-				clickHandler = (panel, user, clickType, slot) -> {
-					this.consumer.accept(true, this.value);
-
-					return true;
-				};
-				break;
-			}
-			case CANCEL:
-			{
-				name = this.user.getTranslation("challenges.gui.buttons.admin.cancel");
-				description = Collections.singletonList(this.user.getTranslation("challenges.gui.descriptions.admin.cancel"));
-				icon = new ItemStack(Material.OAK_DOOR);
-				clickHandler = (panel, user, clickType, slot) -> {
-					this.consumer.accept(false, this.value);
-
-					return true;
-				};
-				break;
-			}
-			case VALUE:
-			{
-				name = this.user.getTranslation("challenges.gui.buttons.admin.value");
-				description = new ArrayList<>();
-				description.add(this.user.getTranslation("challenges.gui.descriptions.current-value", "[value]", ""));
-				description.addAll(this.value);
-				icon = new ItemStack(Material.PAPER);
-				clickHandler = (panel, user, clickType, slot) -> true;
-				break;
-			}
-			case ADD:
-			{
-				name = this.user.getTranslation("challenges.gui.buttons.admin.add");
-				description = Collections.emptyList();
-				icon = new ItemStack(Material.WHITE_STAINED_GLASS_PANE);
-				clickHandler = (panel, user, clickType, slot) -> {
-
-					this.getStringInput(value -> {
-							if (value != null)
-							{
-								this.value.add(value);
-							}
-
-							// Reopen GUI.
-							this.build();
-						},
-						this.user.getTranslation("challenges.gui.descriptions.admin.add-text-line"));
-
-					return true;
-				};
-				break;
-			}
-			case CLEAR:
-			{
-				name = this.user.getTranslation("challenges.gui.buttons.admin.clear");
-				description = Collections.emptyList();
-				icon = new ItemStack(Material.RED_STAINED_GLASS_PANE);
-				clickHandler = (panel, user, clickType, slot) -> {
-					this.value.clear();
-					this.build();
-					return true;
-				};
-				break;
-			}
-			case REMOVE:
-			{
-				name = this.user.getTranslation("challenges.gui.buttons.admin.remove-empty");
-				description = Collections.emptyList();
-				icon = new ItemStack(Material.BLUE_STAINED_GLASS_PANE);
-				clickHandler = (panel, user, clickType, slot) -> {
-					this.value.removeIf(String::isEmpty);
-
-					this.build();
-					return true;
-				};
-				break;
-			}
-			default:
-				return null;
-		}
-
-		return new PanelItemBuilder().
-			icon(icon).
-			name(name).
-			description(GuiUtils.stringSplit(description, this.lineLength)).
-			glow(false).
-			clickHandler(clickHandler).
-			build();
-	}
-
-
-	/**
-	 * This method creates paper icon that represents single line from list.
-	 * @param element Paper Icon name
-	 * @return PanelItem.
-	 */
-	private PanelItem createStringElement(String element, int stringIndex)
-	{
-		return new PanelItemBuilder().
-			name(element).
-			icon(Material.PAPER).
-			clickHandler((panel, user1, clickType, i) -> {
-
-				this.getStringInput(
-					value -> {
-						if (value != null)
-						{
-							this.value.set(stringIndex, value);
-						}
-
-						// Reopen GUI
-						this.build();
-					},
-					this.user.getTranslation("challenges.gui.descriptions.admin.edit-text-line"),
-					element);
-
-				return true;
-			}).build();
-	}
-
-
-	/**
-	 * This method will close opened gui and writes inputText in chat. After players answers on inputText in
-	 * chat, message will trigger consumer and gui will reopen.
-	 * @param consumer Consumer that accepts player output text.
-	 * @param question Message that will be displayed in chat when player triggers conversion.
-	 */
-	private void getStringInput(Consumer<String> consumer, @NonNull String question)
-	{
-		this.getStringInput(consumer, question, null);
-	}
-
-
-	/**
-	 * This method will close opened gui and writes inputText in chat. After players answers on inputText in
-	 * chat, message will trigger consumer and gui will reopen.
-	 * @param consumer Consumer that accepts player output text.
-	 * @param question Message that will be displayed in chat when player triggers conversion.
-	 * @param message Message that will be set in player text field when clicked on question.
-	 */
-	private void getStringInput(Consumer<String> consumer, @NonNull String question, @Nullable String message)
-	{
-		final User user = this.user;
-
-		Conversation conversation =
-			new ConversationFactory(BentoBox.getInstance()).withFirstPrompt(
-				new StringPrompt()
-				{
-					/**
-					 * @see Prompt#getPromptText(ConversationContext)
-					 */
-					@Override
-					public String getPromptText(ConversationContext conversationContext)
-					{
-						// Close input GUI.
-						user.closeInventory();
-
-						if (message != null)
-						{
-							// Create Edit Text message.
-							TextComponent component = new TextComponent(user.getTranslation("challenges.gui.descriptions.admin.click-to-edit"));
-							component.setClickEvent(new ClickEvent(ClickEvent.Action.SUGGEST_COMMAND, message));
-							// Send question and message to player.
-							user.getPlayer().spigot().sendMessage(component);
-						}
-
-						// There are no editable message. Just return question.
-						return question;
-					}
-
-
-					/**
-					 * @see Prompt#acceptInput(ConversationContext, String)
-					 */
-					@Override
-					public Prompt acceptInput(ConversationContext conversationContext, String answer)
-					{
-						// Add answer to consumer.
-						consumer.accept(answer);
-						// End conversation
-						return Prompt.END_OF_CONVERSATION;
-					}
-				}).
-				// On cancel conversation will be closed.
-				withEscapeSequence("cancel").
-				// Use null value in consumer to detect if user has abandoned conversation.
-				addConversationAbandonedListener(abandonedEvent ->
-				{
-					if (!abandonedEvent.gracefulExit())
-					{
-						consumer.accept(null);
-					}
-				}).
-				withLocalEcho(false).
-				withPrefix(context -> user.getTranslation("challenges.gui.questions.prefix")).
-				buildConversation(user.getPlayer());
-
-		conversation.begin();
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Enums
-// ---------------------------------------------------------------------
-
-
-	/**
-	 * This enum holds all button values in current gui.
-	 */
-	private enum Button
-	{
-		VALUE,
-		ADD,
-		REMOVE,
-		CANCEL,
-		CLEAR,
-		SAVE
-	}
-
-
-// ---------------------------------------------------------------------
-// Section: Variables
-// ---------------------------------------------------------------------
-
-
-	/**
-	 * This variable stores consumer.
-	 */
-	private BiConsumer<Boolean, List<String>> consumer;
-
-	/**
-	 * User who runs GUI.
-	 */
-	private User user;
-
-	/**
-	 * Current value.
-	 */
-	private List<String> value;
-
-	/**
-	 * This variable stores how large line can be, before warp it.
-	 */
-	private int lineLength;
-}

src/main/java/world/bentobox/challenges/utils/Constants.java

@@ -0,0 +1,291 @@
+//
+// Created by BONNe
+// Copyright - 2020
+//
+
+
+package world.bentobox.challenges.utils;
+
+
+/**
+ * This class contains String constants used in messages and guis.
+ */
+public class Constants
+{
+    /**
+     * Reference string to ADDON_NAME in translations.
+     */
+    public static final String ADDON_NAME = "challenges.";
+
+// ---------------------------------------------------------------------
+// Section: Commands
+// ---------------------------------------------------------------------
+
+
+    /**
+     * Reference string to Commands in translations.
+     */
+    public static final String COMMANDS = ADDON_NAME + "commands.";
+
+    /**
+     * Reference string to Admin in translations.
+     */
+    public static final String ADMIN_COMMANDS = COMMANDS + "admin.";
+
+    /**
+     * Reference string to Player in translations.
+     */
+    public static final String PLAYER_COMMANDS = COMMANDS + "player.";
+
+// ---------------------------------------------------------------------
+// Section: GUI
+// ---------------------------------------------------------------------
+
+    /**
+     * Reference string to GUI in translations.
+     */
+    public static final String GUI = ADDON_NAME + "gui.";
+
+    /**
+     * Reference string to TITLE in translations.
+     */
+    public static final String TITLE = GUI + "titles.";
+
+    /**
+     * Reference string to BUTTON in translations.
+     */
+    public static final String BUTTON = GUI + "buttons.";
+
+    /**
+     * Reference string to Biome group Buttons in translations.
+     */
+    public static final String BIOME_GROUP_BUTTON = BUTTON + "biome-groups.";
+
+    /**
+     * Reference string to generator type Buttons in translations.
+     */
+    public static final String GENERATOR_TYPE_BUTTON = BUTTON + "generator-types.";
+
+    /**
+     * Reference string to TIPS in translations.
+     */
+    public static final String TIPS = GUI + "tips.";
+
+    /**
+     * Reference string to DESCRIPTION in translations.
+     */
+    public static final String DESCRIPTIONS = GUI + "descriptions.";
+
+    /**
+     * Reference string to Messages in translations.
+     */
+    public static final String MESSAGES = ADDON_NAME + "messages.";
+
+    /**
+     * Reference string to Errors in translations.
+     */
+    public static final String ERRORS = ADDON_NAME + "errors.";
+
+    /**
+     * Reference string to Questions in translations.
+     */
+    public static final String CONVERSATIONS = ADDON_NAME + "conversations.";
+
+// ---------------------------------------------------------------------
+// Section: Other
+// ---------------------------------------------------------------------
+
+    /**
+     * Reference string to Biomes in translations.
+     */
+    public static final String BIOMES = ADDON_NAME + "biomes.";
+
+    /**
+     * Reference string to materials in translations.
+     */
+    public static final String MATERIALS = ADDON_NAME + "materials.";
+
+    /**
+     * Reference string to entities in translations.
+     */
+    public static final String ENTITIES = ADDON_NAME + "entities.";
+
+    /**
+     * Reference string to Types in translations.
+     */
+    public static final String TYPES = ADDON_NAME + "types.";
+
+// ---------------------------------------------------------------------
+// Section: Parameters
+// ---------------------------------------------------------------------
+
+    /**
+     * Reference string to generator parameter in translations.
+     */
+    public static final String GENERATOR = "[generator]";
+
+    /**
+     * Reference string to bundle parameter in translations.
+     */
+    public static final String BUNDLE = "[bundle]";
+
+    /**
+     * Reference string to gamemode parameter in translations.
+     */
+    public static final String GAMEMODE = "[gamemode]";
+
+    /**
+     * Reference string to world parameter in translations.
+     */
+    public static final String WORLD = "[world]";
+
+    /**
+     * Reference string to value parameter in translations.
+     */
+    public static final String VALUE = "[value]";
+
+    /**
+     * Reference string to block parameter in translations.
+     */
+    public static final String BLOCK = "[material]";
+
+    /**
+     * Reference string to file parameter in translations.
+     */
+    public static final String FILE = "[file]";
+
+    /**
+     * Reference string to id parameter in translations.
+     */
+    public static final String ID = "[id]";
+
+    /**
+     * Reference string to min parameter in translations.
+     */
+    public static final String MIN = "[min]";
+
+    /**
+     * Reference string to max parameter in translations.
+     */
+    public static final String MAX = "[max]";
+
+    /**
+     * Reference to an author parameter in translation.
+     */
+    public static final String AUTHOR = "[author]";
+
+    /**
+     * Reference to an lang parameter in translation.
+     */
+    public static final String LANG = "[lang]";
+
+    /**
+     * Reference to an version parameter in translation.
+     */
+    public static final String VERSION = "[version]";
+
+    /**
+     * Reference to an generators parameter in translation.
+     */
+    public static final String GENERATORS = "[generators]";
+
+    /**
+     * Reference to an bundles parameter in translation.
+     */
+    public static final String BUNDLES = "[bundles]";
+
+    /**
+     * Reference to number formant in 0.X
+     */
+    public static final String TENS = "[#.#]";
+
+    /**
+     * Reference to number formant in 0.0X
+     */
+    public static final String HUNDREDS = "[#.##]";
+
+    /**
+     * Reference to number formant in 0.00X
+     */
+    public static final String THOUSANDS = "[#.###]";
+
+    /**
+     * Reference to number formant in 0.000X
+     */
+    public static final String TEN_THOUSANDS = "[#.####]";
+
+    /**
+     * Reference to number formant in 0.0000X
+     */
+    public static final String HUNDRED_THOUSANDS = "[#.#####]";
+
+    /**
+     * Reference to island in translations.
+     */
+    public static final String ISLAND = "[island]";
+
+    /**
+     * Reference string to number parameter in translations.
+     */
+    public static final String NUMBER = "[number]";
+
+    /**
+     * Reference string to type parameter in translations.
+     */
+    public static final String TYPE = "[type]";
+
+    /**
+     * Reference string to permission parameter in translations.
+     */
+    public static final String PERMISSION = "[permission]";
+
+    /**
+     * Reference string to biome parameter in translations.
+     */
+    public static final String BIOME = "[biome]";
+
+    /**
+     * Reference string to player parameter in translations.
+     */
+    public static final String PLAYER = "[player]";
+
+    /**
+     * Reference string to owner parameter in translations.
+     */
+    public static final String OWNER = "[owner]";
+
+    /**
+     * Reference string to members parameter in translations.
+     */
+    public static final String MEMBERS = "[members]";
+
+    /**
+     * Reference string to name parameter in translations.
+     */
+    public static final String NAME = "[name]";
+
+    /**
+     * Reference string to description parameter in translations.
+     */
+    public static final String DESCRIPTION = "[description]";
+
+    public static final String CHALLENGE = "[challenge]";
+
+    public static final String REQUIREMENTS = "[requirements]";
+
+    public static final String REWARDS = "[rewards]";
+
+    public static final String STATUS = "[status]";
+
+    public static final String LEVEL = "[level]";
+
+    public static final String ENVIRONMENT = "[environment]";
+
+    public static final String TYPE_REQUIREMENT = "[type-requirement]";
+
+    public static final String PERMISSIONS = "[permissions]";
+
+    public static final String MATERIAL = "[material]";
+
+    public static final String ENTITY = "[entity]";
+}

src/main/java/world/bentobox/challenges/utils/GuiUtils.java

@@ -3,8 +3,6 @@ package world.bentobox.challenges.utils;
 
 import java.util.*;
 
-import org.apache.commons.lang.WordUtils;
-import org.bukkit.ChatColor;
 import org.bukkit.Material;
 import org.bukkit.entity.EntityType;
 import org.bukkit.inventory.ItemStack;
@@ -366,74 +364,9 @@ public class GuiUtils
 		private static BorderBlock getPanelBorder(Material material)
 		{
 			ItemStack itemStack = new ItemStack(material);
-			itemStack.getItemMeta().setDisplayName(" ");
+			itemStack.getItemMeta().setDisplayName("&r&8");
 
 			return new BorderBlock(itemStack);
 		}
 	}
-
-
-	/**
-	 * Simple splitter
-	 *
-	 * @param string - string to be split
-	 * @param warpLength - whn warp should be affected.
-	 * @return list of split strings
-	 */
-	public static List<String> stringSplit(String string, int warpLength)
-	{
-		// Remove all ending lines from string.
-		string = string.replaceAll("([\\r\\n])", "\\|");
-		string = ChatColor.translateAlternateColorCodes('&', string);
-		// Check length of lines
-		List<String> result = new ArrayList<>();
-
-		Arrays.stream(string.split("\\|")).
-			map(line -> Arrays.asList(WordUtils.wrap(line, warpLength).split(System.getProperty("line.separator")))).
-			forEach(result::addAll);
-
-		// Fix colors, as splitting my lost that information.
-
-		for (int i = 0, resultSize = result.size(); i < resultSize; i++)
-		{
-			if (i > 0)
-			{
-				String lastColor = ChatColor.getLastColors(result.get(i - 1));
-				result.set(i, lastColor + result.get(i));
-			}
-		}
-
-		return result;
-	}
-
-
-	/**
-	 * Simple splitter for all strings in list.
-	 * @param stringList - list of string to be split
-	 * @param warpLength - whn warp should be affected.
-	 * @return list of split strings
-	 */
-	public static List<String> stringSplit(List<String> stringList, int warpLength)
-	{
-		if (stringList.isEmpty())
-		{
-			return stringList;
-		}
-
-		List<String> newList = new ArrayList<>(stringList.size());
-		stringList.stream().map(string -> GuiUtils.stringSplit(string, warpLength)).forEach(newList::addAll);
-		return newList;
-	}
-
-
-	/**
-	 * Sanitizes the provided input.
-	 * It replaces spaces and hyphens with underscores and lower cases the input.
-	 * @param input input to sanitize
-	 * @return sanitized input
-	 */
-	public static String sanitizeInput(String input)
-	{
-		return input.toLowerCase(Locale.ENGLISH).replace(" ", "_").replace("-", "_");
-	}
 }

src/main/java/world/bentobox/challenges/utils/Utils.java

@@ -3,12 +3,19 @@ package world.bentobox.challenges.utils;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Locale;
 
+import org.bukkit.ChatColor;
 import org.bukkit.Material;
+import org.bukkit.Statistic;
 import org.bukkit.World;
+import org.bukkit.entity.EntityType;
 import org.bukkit.inventory.ItemStack;
+import org.eclipse.jdt.annotation.Nullable;
 
 import world.bentobox.bentobox.BentoBox;
+import world.bentobox.bentobox.api.user.User;
+import world.bentobox.bentobox.util.Util;
 
 
 /**
@@ -152,4 +159,103 @@ public class Utils
 
 		return currentValue;
 	}
+
+
+	/**
+	 * Sanitizes the provided input. It replaces spaces and hyphens with underscores and lower cases the input.
+	 * This code also removes all color codes from the input.
+	 * @param input input to sanitize
+	 * @return sanitized input
+	 */
+	public static String sanitizeInput(String input)
+	{
+		return ChatColor.stripColor(
+			Util.translateColorCodes(input.toLowerCase(Locale.ENGLISH).
+				replace(" ", "_").
+				replace("-", "_")));
+	}
+
+
+	/**
+	 * Send given message to user and add prefix to the start of the message.
+	 *
+	 * @param user User who need to receive message.
+	 * @param message String of message that must be send.
+	 */
+	public static void sendMessage(User user, String message)
+	{
+		user.sendMessage(user.getTranslation(Constants.CONVERSATIONS + "prefix") + message);
+	}
+
+
+
+	public static String prettifyObject(World.Environment object, User user)
+	{
+		return Util.prettifyText(object.name());
+	}
+
+	public static String prettifyObject(@Nullable Material object, User user)
+	{
+		if (object == null)
+		{
+			return "";
+		}
+
+		return Util.prettifyText(object.name());
+	}
+
+
+	public static String prettifyObject(@Nullable EntityType object, User user)
+	{
+		if (object == null)
+		{
+			return "";
+		}
+
+		return Util.prettifyText(object.name());
+	}
+
+
+	public static String prettifyObject(@Nullable ItemStack object, User user)
+	{
+		if (object == null)
+		{
+			return "";
+		}
+
+		return Util.prettifyText(object.getType().name());
+	}
+
+
+	public static String prettifyObject(@Nullable Statistic object, User user)
+	{
+		if (object == null)
+		{
+			return "";
+		}
+
+		return Util.prettifyText(object.name());
+	}
+
+
+	public static String prettifyDescription(@Nullable Statistic object, User user)
+	{
+		if (object == null)
+		{
+			return "";
+		}
+
+		return Util.prettifyText(object.name());
+	}
+
+
+	public static String prettifyDescription(World.Environment object, User user)
+	{
+		if (object == null)
+		{
+			return "";
+		}
+
+		return Util.prettifyText(object.name());
+	}
 }