Started work on item hovering.

src/main/java/net/minestom/server/chat/ChatHoverEvent.java

@@ -3,6 +3,7 @@ package net.minestom.server.chat;
 import com.google.gson.JsonObject;
 import net.minestom.server.entity.Entity;
 import net.minestom.server.entity.EntityType;
+import net.minestom.server.item.ItemFlag;
 import net.minestom.server.item.ItemStack;
 
 /**
@@ -26,6 +27,22 @@ public class ChatHoverEvent {
         this.isJson = true;
     }
 
+    protected String getAction() {
+        return action;
+    }
+
+    protected String getValue() {
+        return value;
+    }
+
+    protected JsonObject getValueObject() {
+        return valueObject;
+    }
+
+    protected boolean isJson() {
+        return isJson;
+    }
+
     /**
      * Show a {@link ColoredText} when hovered
      *
@@ -53,7 +70,101 @@ public class ChatHoverEvent {
      * @return the chat hover event
      */
     public static ChatHoverEvent showItem(ItemStack itemStack) {
-        return new ChatHoverEvent("show_item", "{id:35,Damage:5,Count:2,tag:{display:{Name:Testing}}}");
+        JsonObject itemJson = new JsonObject();
+        // Basic Item structure
+        itemJson.addProperty("id", itemStack.getMaterial().getName());
+        itemJson.addProperty("Count", itemStack.getAmount());
+
+        JsonObject tagJson = new JsonObject();
+
+        // General tags
+        tagJson.addProperty("Damage", itemStack.getDamage());
+        tagJson.addProperty("Unbreakable", itemStack.isUnbreakable());
+        // TODO: CanDestroy
+        tagJson.addProperty("CustomModelData", itemStack.getCustomModelData());
+
+        // TODO: BlockTags
+
+        // Enchantments
+        // TODO: Enchantments
+        // TODO: StoredEnchantments
+        // TODO: RepairCost
+
+        // TODO: Attribute modifiers
+
+        // Potion Effects
+        // TODO: CustomPotionEffects
+        // TODO: Potion
+        // TODO: CustomPotionColor
+
+        // Crossbows
+        // TODO: ChargedProjectiles
+        // TODO: Charged
+
+        // Display
+        JsonObject displayJson = new JsonObject();
+        // TODO: Color (Leather armour)
+        // This is done as this contains a json text component describing the item's name.
+        // We replace it in the last step, as adding it now would replace it with lenient JSON which MC doesn't want.
+        displayJson.addProperty("Name", "%item_name%");
+        // TODO: Lore
+
+        // HideFlags
+        if (!itemStack.getItemFlags().isEmpty()) {
+            int bitField = itemStack.getItemFlags().stream().mapToInt(ItemFlag::getBitFieldPart).sum();
+            tagJson.addProperty("HideFlags", bitField);
+        }
+
+        // WrittenBooks
+        // TODO: Resolved
+        // TODO: Generation
+        // TODO: Author
+        // TODO: Title
+        // TODO: Pages
+
+        // Book and Quills
+        // TODO: Pages
+
+        // Player Heads
+        // TODO: Alot check https://minecraft.gamepedia.com/Player.dat_format#Item_structure#Player_Heads
+
+        // Fireworks
+        // TODO: Alot check https://minecraft.gamepedia.com/Player.dat_format#Item_structure#Fireworks
+
+        // Armorstands and Spawn Eggs
+        // TODO: EntityTag
+
+        // Buckets of Fish
+        // TODO: BucketVariantTag
+        // TODO: ENtityTag
+
+        // Maps
+        // TODO: Alot check https://minecraft.gamepedia.com/Player.dat_format#Item_structure#Maps
+
+        // Suspcious Stew
+        // TODO: Effects
+
+        // Debug Sticks
+        // TODO: DebugProperty
+
+        // Compasses
+        // TODO: LodestoneTracked
+        // TODO: LodestoneDimension
+        // TODO: LodestonePos
+
+
+        tagJson.add("display", displayJson);
+        itemJson.add("tag", tagJson);
+
+
+        final String item = itemJson.toString()
+                .replaceAll("\"(\\w+)\":", "$1:")
+                // TODO: Since embedded JSON is wrapped using (')s we should be able to use Regex to ignore any keys wrapped by (')s.
+                .replaceAll("\"%item_name%\"", '\'' + itemStack.getDisplayName().getJsonObject().toString() + '\'');
+
+        System.out.println(item);
+        // Use regex to remove the qoutes around the keys (MC wants this).
+        return new ChatHoverEvent("show_item", item);
     }
 
     /**
@@ -73,20 +184,4 @@ public class ChatHoverEvent {
         object.addProperty("type", type);
         return new ChatHoverEvent("show_entity", object);
     }
-
-    protected String getAction() {
-        return action;
-    }
-
-    protected String getValue() {
-        return value;
-    }
-
-    protected JsonObject getValueObject() {
-        return valueObject;
-    }
-
-    protected boolean isJson() {
-        return isJson;
-    }
 }

src/main/java/net/minestom/server/item/ItemFlag.java

@@ -1,10 +1,19 @@
 package net.minestom.server.item;
 
 public enum ItemFlag {
-    HIDE_ENCHANTS,
-    HIDE_ATTRIBUTES,
-    HIDE_UNBREAKABLE,
-    HIDE_DESTROYS,
-    HIDE_PLACED_ON,
-    HIDE_POTION_EFFECTS,
+    HIDE_ENCHANTS(1),
+    HIDE_ATTRIBUTES(2),
+    HIDE_UNBREAKABLE(4),
+    HIDE_DESTROYS(8),
+    HIDE_PLACED_ON(16),
+    HIDE_POTION_EFFECTS(32);
+
+    private final int bitFieldPart;
+    ItemFlag(int bit) {
+        this.bitFieldPart = bit;
+    }
+
+    public int getBitFieldPart() {
+        return bitFieldPart;
+    }
 }

src/main/java/net/minestom/server/listener/ChatMessageListener.java

@@ -1,17 +1,28 @@
 package net.minestom.server.listener;
 
 import net.minestom.server.MinecraftServer;
-import net.minestom.server.chat.*;
+import net.minestom.server.attribute.Attribute;
+import net.minestom.server.attribute.AttributeOperation;
+import net.minestom.server.chat.ChatClickEvent;
+import net.minestom.server.chat.ChatColor;
+import net.minestom.server.chat.ChatHoverEvent;
+import net.minestom.server.chat.ColoredText;
+import net.minestom.server.chat.RichMessage;
 import net.minestom.server.command.CommandManager;
 import net.minestom.server.entity.Player;
 import net.minestom.server.event.player.PlayerChatEvent;
 import net.minestom.server.event.player.PlayerCommandEvent;
+import net.minestom.server.item.ItemStack;
+import net.minestom.server.item.Material;
+import net.minestom.server.item.attribute.AttributeSlot;
+import net.minestom.server.item.attribute.ItemAttribute;
 import net.minestom.server.network.ConnectionManager;
 import net.minestom.server.network.PacketWriterUtils;
 import net.minestom.server.network.packet.client.play.ClientChatMessagePacket;
 import net.minestom.server.network.packet.server.play.ChatMessagePacket;
 
 import java.util.Collection;
+import java.util.UUID;
 import java.util.function.Function;
 
 public class ChatMessageListener {
@@ -75,8 +86,15 @@ public class ChatMessageListener {
 
         final ColoredText usernameText = ColoredText.of(String.format("<%s>", username));
 
+        ItemStack itemStack = new ItemStack(Material.DIAMOND_SWORD, (byte) 1);
+        itemStack.addAttribute(
+                new ItemAttribute(UUID.randomUUID(), Attribute.ATTACK_DAMAGE.getKey(),
+                        Attribute.ATTACK_DAMAGE, AttributeOperation.ADDITION, 16.0, AttributeSlot.MAINHAND)
+        );
+        itemStack.setDisplayName(ColoredText.of(ChatColor.BRIGHT_GREEN + "Weird" + ChatColor.YELLOW + "Fence"));
+
         final RichMessage richMessage = RichMessage.of(usernameText)
-                .setHoverEvent(ChatHoverEvent.showText(ColoredText.of(ChatColor.GRAY + "Its " + username)))
+                .setHoverEvent(ChatHoverEvent.showItem(itemStack))
                 .setClickEvent(ChatClickEvent.suggestCommand("/msg " + username + " "))
                 .append(ColoredText.of(" " + chatEvent.getMessage()));