Make help command use descriptions and usages

src/main/java/wtf/beatrice/hidekobot/commands/base/Alias.java

@@ -0,0 +1,23 @@
+package wtf.beatrice.hidekobot.commands.base;
+
+import wtf.beatrice.hidekobot.objects.commands.MessageCommand;
+
+import java.util.LinkedList;
+
+public class Alias
+{
+    public static String generateNiceAliases(MessageCommand command)
+    {
+        LinkedList<String> aliases = command.getCommandLabels();
+        StringBuilder aliasesStringBuilder = new StringBuilder();
+        for(int i = 0; i < aliases.size(); i++)
+        {
+            aliasesStringBuilder.append("`").append(aliases.get(i)).append("`");
+
+            if(i + 1 != aliases.size())
+                aliasesStringBuilder.append(", "); // separate with comma except on last iteration
+        }
+
+        return aliasesStringBuilder.toString();
+    }
+}

src/main/java/wtf/beatrice/hidekobot/commands/message/AliasCommand.java

@@ -5,6 +5,7 @@ import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.Cache;
+import wtf.beatrice.hidekobot.commands.base.Alias;
 import wtf.beatrice.hidekobot.objects.commands.CommandCategory;
 import wtf.beatrice.hidekobot.objects.commands.MessageCommand;
 
@@ -37,6 +38,18 @@ public class AliasCommand implements MessageCommand
         return CommandCategory.TOOLS;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "See other command aliases.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return "<command>";
+    }
+
     @Override
     public void runCommand(MessageReceivedEvent event, String label, String[] args)
     {
@@ -54,19 +67,11 @@ public class AliasCommand implements MessageCommand
             return;
         }
 
-        LinkedList<String> aliases = command.getCommandLabels();
-        StringBuilder aliasesStringBuilder = new StringBuilder();
-        aliasesStringBuilder.append("Aliases for **").append(aliases.get(0)).append("**: ");
-        for(int i = 0; i < aliases.size(); i++)
-        {
-            aliasesStringBuilder.append("`").append(aliases.get(i)).append("`");
-
-            if(i + 1 != aliases.size())
-                aliasesStringBuilder.append(", "); // separate with comma except on last iteration
-        }
+        String aliases = Alias.generateNiceAliases(command);
+        aliases =  "Aliases for **" + command.getCommandLabels().get(0) + "**: " + aliases;
 
         event.getMessage()
-                .reply(aliasesStringBuilder.toString())
+                .reply(aliases)
                 .queue();
 
     }

src/main/java/wtf/beatrice/hidekobot/commands/message/AvatarCommand.java

@@ -36,6 +36,18 @@ public class AvatarCommand  implements MessageCommand
         return false;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Get someone's avatar, or your own. You can additionally specify a resolution.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return "[mentioned user] [resolution]";
+    }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {
@@ -47,7 +59,7 @@ public class AvatarCommand  implements MessageCommand
     {
         int[] acceptedSizes = Cache.getSupportedAvatarResolutions();
 
-        User user = null;
+        User user;
         int resolution = -1;
 
         // we have no specific order for user and resolution, so let's try parsing any arg as resolution

src/main/java/wtf/beatrice/hidekobot/commands/message/BotInfoCommand.java

@@ -33,6 +33,18 @@ public class BotInfoCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Get general info about the bot.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return null;
+    }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {

src/main/java/wtf/beatrice/hidekobot/commands/message/ClearCommand.java

@@ -5,6 +5,7 @@ import net.dv8tion.jda.api.entities.Message;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
 import net.dv8tion.jda.api.interactions.components.buttons.Button;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.Cache;
 import wtf.beatrice.hidekobot.commands.base.ClearChat;
 import wtf.beatrice.hidekobot.objects.commands.CommandCategory;
@@ -29,12 +30,25 @@ public class ClearCommand implements MessageCommand
     public boolean passRawArgs() {
         return false;
     }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.MODERATION;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Clear the current channel's chat history.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return "[amount]";
+    }
+
     @Override
     public void runCommand(MessageReceivedEvent event, String label, String[] args)
     {

src/main/java/wtf/beatrice/hidekobot/commands/message/CoinFlipCommand.java

@@ -31,6 +31,18 @@ public class CoinFlipCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Flip a coin.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return null;
+    }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {

src/main/java/wtf/beatrice/hidekobot/commands/message/DiceRollCommand.java

@@ -30,6 +30,23 @@ public class DiceRollCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Roll dice. You can roll multiple dice at the same time." +
+                "\nExamples:" +
+                "\n - `d8 10` to roll an 8-sided die 10 times." +
+                "\n - `d12 3 d5 10` to roll a 12-sided die 3 times, and then a 5-sided die 10 times." +
+                "\n - `30` to roll a standard 6-sided die 30 times." +
+                "\n - `d10` to roll a 10-sided die once.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return "[dice size] [rolls]";
+    }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {

src/main/java/wtf/beatrice/hidekobot/commands/message/HelloCommand.java

@@ -3,6 +3,7 @@ package wtf.beatrice.hidekobot.commands.message;
 import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.objects.commands.CommandCategory;
 import wtf.beatrice.hidekobot.objects.commands.MessageCommand;
 
@@ -26,6 +27,18 @@ public class HelloCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Get pinged by the bot.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return null;
+    }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {

src/main/java/wtf/beatrice/hidekobot/commands/message/HelpCommand.java

@@ -7,6 +7,7 @@ import org.apache.commons.text.WordUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.Cache;
+import wtf.beatrice.hidekobot.commands.base.Alias;
 import wtf.beatrice.hidekobot.commands.base.Say;
 import wtf.beatrice.hidekobot.objects.commands.CommandCategory;
 import wtf.beatrice.hidekobot.objects.commands.MessageCommand;
@@ -34,6 +35,18 @@ public class HelpCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Get general help on the bot. Specify a command if you want specific help about that command.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return "[command]";
+    }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {
@@ -91,6 +104,51 @@ public class HelpCommand implements MessageCommand
                 embedBuilder.addField(niceCategoryName, commandsList.toString(), false);
             }
 
+            event.getMessage().replyEmbeds(embedBuilder.build()).queue();
+        } else {
+
+            String commandLabel = args[0].toLowerCase();
+            MessageCommand command = Cache.getMessageCommandListener().getRegisteredCommand(commandLabel);
+            if(command == null)
+            {
+                event.getMessage().reply("Unrecognized command: `" + commandLabel + "`!").queue(); // todo prettier
+                return;
+            }
+
+            commandLabel = command.getCommandLabels().get(0);
+            String usage = "`" + Cache.getBotPrefix() + " " + commandLabel;
+            String internalUsage = command.getUsage();
+            if(internalUsage != null) usage += " " + internalUsage;
+            usage += "`";
+
+            String aliases = Alias.generateNiceAliases(command);
+
+            List<Permission> permissions = command.getPermissions();
+            StringBuilder permissionsStringBuilder = new StringBuilder();
+            if(permissions == null)
+            {
+                permissionsStringBuilder = new StringBuilder("Available to everyone");
+            } else {
+                for(int i = 0; i < permissions.size(); i++)
+                {
+                    Permission permission = permissions.get(i);
+                    permissionsStringBuilder.append("`").append(permission.getName()).append("`");
+
+                    if(i + 1 != permissions.size())
+                        permissionsStringBuilder.append(", "); // separate with comma expect on last iteration
+                }
+            }
+
+            EmbedBuilder embedBuilder = new EmbedBuilder();
+
+            embedBuilder.setColor(Cache.getBotColor());
+            embedBuilder.setTitle(WordUtils.capitalizeFully(commandLabel + " help"));
+
+            embedBuilder.addField("Description", command.getDescription(), false);
+            embedBuilder.addField("Usage", usage, false);
+            embedBuilder.addField("Aliases", aliases, false);
+            embedBuilder.addField("Permissions", permissionsStringBuilder.toString(), false);
+
             event.getMessage().replyEmbeds(embedBuilder.build()).queue();
         }
     }

src/main/java/wtf/beatrice/hidekobot/commands/message/InviteCommand.java

@@ -34,6 +34,18 @@ public class InviteCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Get the bot's invite link.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return null;
+    }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {

src/main/java/wtf/beatrice/hidekobot/commands/message/LoveCalculatorCommand.java

@@ -39,6 +39,18 @@ public class LoveCalculatorCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Calculate how much two people love each other. You can mention two people or just one.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return "<person 1> [person 2]";
+    }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {
@@ -55,7 +67,9 @@ public class LoveCalculatorCommand implements MessageCommand
 
         if(args.length == 0 || mentions.isEmpty())
         {
-            event.getMessage().reply("\uD83D\uDE22 I need to know who to check!").queue();
+            event.getMessage()
+                    .reply("\uD83D\uDE22 I need to know who to check! Please mention them.")
+                    .queue();
             return;
         }
 

src/main/java/wtf/beatrice/hidekobot/commands/message/MagicBallCommand.java

@@ -30,6 +30,18 @@ public class MagicBallCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Ask a question to the Magic Ball.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return "<question>";
+    }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {

src/main/java/wtf/beatrice/hidekobot/commands/message/SayCommand.java

@@ -30,6 +30,18 @@ public class SayCommand implements MessageCommand
         return true;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Make the bot say something for you.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return "<text>";
+    }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {

src/main/java/wtf/beatrice/hidekobot/commands/message/UrbanDictionaryCommand.java

@@ -36,6 +36,18 @@ public class UrbanDictionaryCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
+    @Override
+    public String getDescription() {
+        return "Look something up in the Urban Dictionary.";
+    }
+
+    @Nullable
+    @Override
+    public String getUsage() {
+        return "<query>";
+    }
+
     @NotNull
     @Override
     public CommandCategory getCategory() {

src/main/java/wtf/beatrice/hidekobot/objects/commands/MessageCommand.java

@@ -48,6 +48,23 @@ public interface MessageCommand
     @NotNull
     CommandCategory getCategory();
 
+    /**
+     * Say what this command does.
+     *
+     * @return a String explaining what this command does.
+     */
+    @NotNull
+    String getDescription();
+
+    /**
+     * Say how people should use this command.
+     *
+     * @return a String explaining how to use the command, excluding the bot prefix and command name. Null if no parameter is needed
+     */
+    @Nullable
+    String getUsage();
+
+
     /**
      * Run the command logic by parsing the event and replying accordingly.
      *