Add custom admin message that informs about non-existing challenges in current world.

src/main/java/world/bentobox/challenges/commands/ChallengesCommand.java

@@ -1,7 +1,9 @@
 package world.bentobox.challenges.commands;
 
 import java.util.List;
+import java.util.Optional;
 
+import world.bentobox.bentobox.api.addons.GameModeAddon;
 import world.bentobox.challenges.ChallengesAddon;
 import world.bentobox.bentobox.api.commands.CompositeCommand;
 import world.bentobox.bentobox.api.user.User;
@@ -19,26 +21,64 @@ public class ChallengesCommand extends CompositeCommand
     }
 
 
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public boolean canExecute(User user, String label, List<String> args)
+    {
+        Optional<GameModeAddon> optionalAddon = this.getAddon().getPlugin().getIWM().getAddon(this.getWorld());
+
+        if (!optionalAddon.isPresent())
+        {
+            // Not a GameMode world.
+            user.sendMessage("general.errors.wrong-world");
+            return false;
+        }
+
+        if (!((ChallengesAddon) this.getAddon()).getChallengesManager().hasAnyChallengeData(this.getWorld()))
+        {
+            // Do not open gui if there is no challenges.
+
+            this.getAddon().getLogger().severe("There are no challenges set up in " + this.getWorld() + "!");
+
+            // Show admin better explanation.
+            if (user.isOp() || user.hasPermission(this.getPermissionPrefix() + ".admin.challenges"))
+            {
+                String topLabel = optionalAddon.get().getAdminCommand().orElseGet(this::getParent).getTopLabel();
+                user.sendMessage("challenges.errors.no-challenges-admin", "[label]", topLabel);
+            }
+            else
+            {
+                user.sendMessage("challenges.errors.no-challenges");
+            }
+
+            return false;
+        }
+
+        if (this.getPlugin().getIslands().getIsland(this.getWorld(), user.getUniqueId()) == null)
+        {
+            // Do not open gui if there is no island for this player.
+            user.sendMessage("general.errors.no-island");
+            return false;
+        }
+
+        return true;
+    }
+
+
     @Override
     public boolean execute(User user, String label, List<String> args)
     {
         // Open up the challenges GUI
         if (user.isPlayer())
         {
-            if (this.getPlugin().getIslands().getIsland(this.getWorld(), user.getUniqueId()) != null)
-            {
-                new ChallengesGUI((ChallengesAddon) this.getAddon(),
-                    this.getWorld(),
-                    user,
-                    this.getTopLabel(),
-                    this.getPermissionPrefix()).build();
-                return true;
-            }
-            else
-            {
-                user.sendMessage("general.errors.no-island");
-                return false;
-            }
+            new ChallengesGUI((ChallengesAddon) this.getAddon(),
+                this.getWorld(),
+                user,
+                this.getTopLabel(),
+                this.getPermissionPrefix()).build();
+            return true;
         }
         // Show help
         showHelp(this, user);
@@ -54,5 +94,6 @@ public class ChallengesCommand extends CompositeCommand
         this.setDescription("challenges.commands.user.main.description");
 
         new CompleteChallengeCommand(this.getAddon(), this);
+        this.setOnlyPlayer(true);
     }
 }

src/main/resources/locales/en-US.yml

@@ -353,6 +353,7 @@ challenges:
         defaults-file-exist: '&cdefaults.json already exists. Use overwrite mode to replace it!'
         defaults-file-error: '&cThere was an error while creating defaults.json file! Check console!'
         no-challenges: '&cChallenges are not implemented in current world!'
+        no-challenges-admin: '&cChallenges are not implemented in current world! You should use &5/[label] challenges &cto adding them!'
         missing-level: '&cChallenge Level [level] is not defined in database. It may case some errors!'
 protection:
     flags:

src/main/resources/locales/lv-LV.yml

@@ -351,6 +351,7 @@ challenges:
         defaults-file-exist: '&cdefaults.json jau eksistē. Lieto overwrite, lai to pārrakstītu!'
         defaults-file-error: '&cRadās kļūda veidojot defaults.json failu! Pārbaudi konsoli!'
         no-challenges: '&cŠajā pasaulē nav izveidoti uzdevumi!'
+        no-challenges-admin: '&cŠajā pasaulē nav izveidoti uzdevumi! Izmanot komandu &5/[label] challenges&c, lai tos pievienotu!'
         missing-level: '&cLīmenis [level] nav definēts datubāzē. Tas var radīt problēmas!'
 protection:
     flags: