Added command system structure.

src/main/java/ca/recrown/islandsurvivalcraft/IslandSurvivalCraft.java

@@ -1,30 +1,38 @@
 package ca.recrown.islandsurvivalcraft;
 
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandSender;
+import org.bukkit.event.HandlerList;
 import org.bukkit.event.Listener;
 import org.bukkit.generator.ChunkGenerator;
 import org.bukkit.plugin.PluginManager;
 import org.bukkit.plugin.java.JavaPlugin;
 
+import ca.recrown.islandsurvivalcraft.interaction.commands.CommandProcessor;
 import ca.recrown.islandsurvivalcraft.world.WorldInfoManager;
 import ca.recrown.islandsurvivalcraft.world.generation.GeneratorModes;
 
 public class IslandSurvivalCraft extends JavaPlugin implements Listener {
     private PluginManager pluginManager;
-    private WorldInfoManager worldInfos;
+    private WorldInfoManager worldInfoManager;
+    private CommandProcessor commandProcessor;
 
     public IslandSurvivalCraft() {
-        worldInfos = new WorldInfoManager();
+        worldInfoManager = new WorldInfoManager();
     }
     
     @Override
     public void onEnable() {
         pluginManager = getServer().getPluginManager();
-        pluginManager.registerEvents(worldInfos, this);
+        pluginManager.registerEvents(worldInfoManager, this);
+        commandProcessor = new CommandProcessor(this);
         super.onEnable();
     }
 
     @Override
     public void onDisable() {
+        HandlerList.unregisterAll(worldInfoManager);
+        commandProcessor = null;
         super.onDisable();
     }
 
@@ -36,7 +44,18 @@ public class IslandSurvivalCraft extends JavaPlugin implements Listener {
         } catch (NullPointerException | IllegalArgumentException e) {
             gID = GeneratorModes.UNIQUE;
         }
-        return worldInfos.getChunkGenerator(getServer().getWorld(worldName), gID);
+        return worldInfoManager.getChunkGenerator(getServer().getWorld(worldName), gID);
     }
 
+    /**
+     * @return the world information manager.
+     */
+    public WorldInfoManager getWorldInfoManager() {
+        return worldInfoManager;
+    }
+
+    @Override
+    public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
+        return commandProcessor.onCommand(sender, command, label, args);
+    }
 }

src/main/java/ca/recrown/islandsurvivalcraft/interaction/commands/CommandProcessor.java

@@ -0,0 +1,45 @@
+package ca.recrown.islandsurvivalcraft.interaction.commands;
+
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.concurrent.CompletableFuture;
+
+import org.bukkit.ChatColor;
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandExecutor;
+import org.bukkit.command.CommandSender;
+import org.bukkit.entity.Player;
+
+import ca.recrown.islandsurvivalcraft.IslandSurvivalCraft;
+
+public class CommandProcessor implements CommandExecutor {
+    private IslandSurvivalCraft islandSurvivalCraft;
+    private HashSet<Commands> initializedCommands = new HashSet<>();
+
+    public CommandProcessor(IslandSurvivalCraft islandSurvivalCraft) {
+        this.islandSurvivalCraft = islandSurvivalCraft;
+    }
+
+    @Override
+    public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
+        if (args.length < 1 || args[0].isEmpty()) return false;
+        Commands currentCommand = null;
+        try {
+            currentCommand = Commands.valueOf(args[0].toUpperCase());
+        } catch (IllegalArgumentException e) {
+            sender.sendMessage(ChatColor.LIGHT_PURPLE + "This command was not understood. Refer to \"/IslandSurvivalCraft help\" for more info.");
+        }
+        if (initializedCommands.add(currentCommand)) currentCommand.initialize(islandSurvivalCraft);
+        String[] commandArguments = Arrays.copyOfRange(args, 1, args.length);
+        CompletableFuture<String> results = currentCommand.invoke(sender, commandArguments);
+        results.thenAccept(s -> {
+            if (sender instanceof Player) {
+                Player player = (Player) sender;
+                if (!player.isOnline()) return;
+            }
+            sender.sendMessage(s != null ? s : "");
+        });
+
+        return true;
+    }
+}

src/main/java/ca/recrown/islandsurvivalcraft/interaction/commands/Commands.java

@@ -0,0 +1,52 @@
+package ca.recrown.islandsurvivalcraft.interaction.commands;
+
+import ca.recrown.islandsurvivalcraft.interaction.commands.runnables.HighlightIslandCommand;
+
+import java.util.concurrent.CompletableFuture;
+
+import org.bukkit.command.CommandSender;
+
+import ca.recrown.islandsurvivalcraft.IslandSurvivalCraft;
+import ca.recrown.islandsurvivalcraft.interaction.commands.runnables.CommandRunnable;
+import ca.recrown.islandsurvivalcraft.interaction.commands.runnables.HelpCommand;
+
+public enum Commands implements CommandRunnable {
+    HIGHLIGHT(new HighlightIslandCommand()),
+    HELP(new HelpCommand()),
+    ;
+
+    private final CommandRunnable commandRunnable;
+    private boolean initialized = false;
+
+    private Commands(CommandRunnable runnable) {
+        this.commandRunnable = runnable;
+    }
+
+    @Override
+    public String toString() {
+        return name().toLowerCase();
+    }
+
+    @Override
+    public CompletableFuture<String> invoke(CommandSender sender, String[] args) {
+        return commandRunnable.invoke(sender, args);
+    }
+
+    @Override
+    public void initialize(IslandSurvivalCraft islandSurvivalCraft) {
+        if (initialized) throw new IllegalStateException("Command already initialized.");
+        initialized = true;
+        commandRunnable.initialize(islandSurvivalCraft);
+    }
+
+    @Override
+    public String getDescription() {
+        return commandRunnable.getDescription();
+    }
+
+    @Override
+    public String getDetailedDescription() {
+        return commandRunnable.getDetailedDescription();
+    }
+
+}

src/main/java/ca/recrown/islandsurvivalcraft/interaction/commands/runnables/CommandRunnable.java

@@ -0,0 +1,34 @@
+package ca.recrown.islandsurvivalcraft.interaction.commands.runnables;
+
+import java.util.concurrent.CompletableFuture;
+
+import org.bukkit.command.CommandSender;
+
+import ca.recrown.islandsurvivalcraft.IslandSurvivalCraft;
+
+public interface CommandRunnable {
+    /**
+     * @return a string that gives users an idea of what this command does. Should be short and not include details on arguments.
+     */
+    public String getDescription();
+
+    /**
+     * @return A more detailed description. Doesn't need to contain information already present in normal description as will print with that one. This string should describe proper usage arguments required.
+     */
+    public String getDetailedDescription();
+
+    /**
+     * Invokes this particular command.
+     * Should check for correct arguments.
+     * @param sender The sender of this command.
+     * @param args The arguments given for this command. May be length of 0, in which case there were no arguments.
+     * @return The completable future for the command. The completable future should ultimately return a message in the form of the string letting the user know the the completed execution, or a failure message.
+     */
+    public CompletableFuture<String> invoke(CommandSender sender, String[] args);
+
+    /**
+     * Initializes the command. Is run the first time this command is run.
+     * @param islandSurvivalCraft
+     */
+    public void initialize(IslandSurvivalCraft islandSurvivalCraft);
+}

src/main/java/ca/recrown/islandsurvivalcraft/interaction/commands/runnables/HelpCommand.java

@@ -0,0 +1,61 @@
+package ca.recrown.islandsurvivalcraft.interaction.commands.runnables;
+
+import java.util.concurrent.CompletableFuture;
+
+import org.bukkit.ChatColor;
+import org.bukkit.command.CommandSender;
+
+import ca.recrown.islandsurvivalcraft.IslandSurvivalCraft;
+import ca.recrown.islandsurvivalcraft.interaction.commands.Commands;
+
+public class HelpCommand implements CommandRunnable {
+    private String helpMessage;
+    @Override
+    public String getDescription() {
+        return "Displays these help messages.";
+    }
+
+    @Override
+    public CompletableFuture<String> invoke(CommandSender sender, String[] args) {
+        CompletableFuture<String> completableFuture = new CompletableFuture<>();
+        if (args == null || args.length == 0) {
+            completableFuture.complete(helpMessage);
+        } else {
+            Commands command = null;
+            try {
+                command = Commands.valueOf(args[0].toUpperCase());
+            } catch (IllegalArgumentException e) {
+                completableFuture.complete(ChatColor.LIGHT_PURPLE + String.format("The request %s does not exist. Please type \"/IslandSurvivalCraft help\" for more info.", args[0]));
+                return completableFuture;
+            }
+            StringBuilder sb = new StringBuilder();
+            sb.append(ChatColor.YELLOW + args[0]);
+            sb.append(": " + ChatColor.GRAY);
+            sb.append(command.getDescription());
+            sb.append("\n" + ChatColor.WHITE);
+            sb.append(command.getDetailedDescription());
+            completableFuture.complete(sb.toString().trim());
+        }
+        return completableFuture;
+    }
+
+    @Override
+    public void initialize(IslandSurvivalCraft islandSurvivalCraft) {
+        StringBuilder stringBuilder = new StringBuilder();
+        Commands[] commands = Commands.values();
+        stringBuilder.append(ChatColor.YELLOW + "Commands:\n");
+        for (int i = 0; i < commands.length; i++) {
+            stringBuilder.append(ChatColor.GREEN + commands[i].toString());
+            stringBuilder.append(": " + ChatColor.WHITE);
+            stringBuilder.append(commands[i].getDescription());
+            stringBuilder.append("\n");
+        }
+        helpMessage = stringBuilder.toString().trim();
+    }
+
+    @Override
+    public String getDetailedDescription() {
+        return " \"islandsurvivalcraft help [command]\". Where [command] is a listed command, can optionally be added to get a detailed look at the command. Help is a command that lists all the other potential commands that may be run. Can also look at the detailed commands. But you knew this since your using help with help...";
+    }
+    
+}

src/main/java/ca/recrown/islandsurvivalcraft/interaction/commands/runnables/HighlightIslandCommand.java

@@ -0,0 +1,97 @@
+package ca.recrown.islandsurvivalcraft.interaction.commands.runnables;
+
+import java.util.HashSet;
+import java.util.LinkedList;
+import java.util.concurrent.CompletableFuture;
+
+import org.bukkit.Bukkit;
+import org.bukkit.Location;
+import org.bukkit.Particle;
+import org.bukkit.World;
+import org.bukkit.command.CommandSender;
+import org.bukkit.entity.Player;
+
+import ca.recrown.islandsurvivalcraft.IslandSurvivalCraft;
+import ca.recrown.islandsurvivalcraft.world.WorldInfo;
+
+public class HighlightIslandCommand implements CommandRunnable {
+    private final int CHECK_RADIUS = 3;
+    private final int PARTICLE_AMOUNT = 2;
+    private final Particle PARTICLE_TYPE = Particle.FIREWORKS_SPARK;
+    private final double OFFSET_X = 0.0d, OFFSET_Y = 0.0d, OFFSET_Z = 0.0d;
+
+    HashSet<Player> playersHighlighting = new HashSet<>();
+    LinkedList<Player> waitingList = new LinkedList<>();
+
+    @Override
+    public String getDescription() {
+        return "Displays particle effects at edge of islands.";
+    }
+
+    @Override
+    public CompletableFuture<String> invoke(CommandSender sender, String[] args) {
+        CompletableFuture<String> completableFuture = new CompletableFuture<>();
+        if (!(sender instanceof Player)) {
+            completableFuture.complete("This command can only be run as a player!");
+            return completableFuture;
+        }
+        Player player = (Player) sender;
+        if (args[0].isEmpty()) {
+            completableFuture.complete("Arguments required. Please refer to \"/IslandSurvivalCraft help\" for more info.");
+            return completableFuture;
+        }
+        if (args[0].toLowerCase().equals("start")) {
+            if (playersHighlighting.add(player)) {
+                waitingList.add(player);
+                completableFuture.complete("You are now highlighting islands.");
+            } else {
+                completableFuture.complete("You are already highlighting islands.");
+            }
+        } else if (args[0].toLowerCase().equals("stop")) {
+            if (playersHighlighting.remove(player)) {
+                completableFuture.complete("You are no longer highlighting islands.");
+            } else {
+                completableFuture.complete("You weren't highlighting islands.");
+            }
+        } else {
+            completableFuture.complete(String.format("Argument \"%d\" was not understood. Please refer to \"/IslandSurvivalCraft help\" for more info.", args[0]));
+        }
+        return completableFuture;
+    }
+
+    @Override
+    public void initialize(IslandSurvivalCraft islandsurvivalcraft) {
+        Bukkit.getScheduler().scheduleSyncRepeatingTask(islandsurvivalcraft, new Runnable() {
+            @Override
+            public void run() {
+                Player player = waitingList.poll();
+                if (player == null || !player.isOnline() || !playersHighlighting.contains(player)) {
+                    playersHighlighting.remove(player);
+                    return;
+                }
+                World world = player.getWorld();
+                WorldInfo worldInfo = islandsurvivalcraft.getWorldInfoManager().retrieve(world);
+                Location playerLocation = player.getLocation();
+                int playerX = playerLocation.getBlockX(), playerY = playerLocation.getBlockY(), playerZ = playerLocation.getBlockZ();
+                for (int x = 1; x < CHECK_RADIUS; x++) {
+                    for (int z = 1; z < CHECK_RADIUS; z++) {
+                        if (worldInfo.getIslandMap().isIsland(playerX + x, playerZ + z)) {
+                            world.spawnParticle(PARTICLE_TYPE, x + playerX, playerY, z + playerZ, PARTICLE_AMOUNT, OFFSET_X, OFFSET_Y, OFFSET_Z);
+                        }
+                        if (worldInfo.getIslandMap().isIsland(playerX - x, playerZ - z)) {
+                            world.spawnParticle(PARTICLE_TYPE, playerX - x, playerY, playerZ - z, PARTICLE_AMOUNT, OFFSET_X, OFFSET_Y, OFFSET_Z);
+                        }
+                    }
+                }
+                waitingList.add(player);
+            }
+        }, 0, 5);
+
+    }
+
+    @Override
+    public String getDetailedDescription() {
+        return "A helpful debugging command to analyze what the plugin considers an island by displaying particle effects around the player that is a part of the island. The <start | stop> argument is required to dicate whether or not to start the highlighting or stop it.";
+    }
+    
+}

src/main/resources/plugin.yml

@@ -6,4 +6,14 @@ description: Adds the gamemode IslandSurvivalCraft.
 depend: []
 load: startup
 api-version: 1.15
-commands:
+commands:
+  IslandSurvivalCraft:
+    aliases: [isc]
+    description: The administration command for Island Survival Craft.
+    usage: Type "/IslandSurvivalCraft help" (or any of its aliases) for a list of commands.
+    permission: islandsurvivalcraft.admin
+    permission-message: This command isn't needed for normal gameplay, and therefore, by default, only operators have access to it.
+permissions:
+  islandsurvivalcraft.admin:
+    description: Gives ability to configure and test Island Survival Craft features in game.
+    default: op