Discord chat commands parser + dispatcher

src/main/java/net/pingex/discordbot/Command.java

@@ -0,0 +1,21 @@
+package net.pingex.discordbot;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Marks a Command as callable from the Discord chat.
+ * @version 0.1-dev
+ * @author Raphael "Pingex" NAAS
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.METHOD)
+public @interface Command
+{
+	/**
+	 * Minimum number of arguments expected
+	 */
+	int minArgs() default 0;
+}

src/main/java/net/pingex/discordbot/CommandDispatcher.java

@@ -0,0 +1,105 @@
+package net.pingex.discordbot;
+
+import sx.blah.discord.api.EventSubscriber;
+import sx.blah.discord.handle.impl.events.MessageReceivedEvent;
+import sx.blah.discord.util.DiscordException;
+import sx.blah.discord.util.HTTP429Exception;
+import sx.blah.discord.util.MissingPermissionsException;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.logging.Logger;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * This class parses and dispatch Discord commands
+ * @version 0.1-dev
+ * @author Raphael "Pingex" NAAS
+ */
+public class CommandDispatcher
+{
+	private Logger logger;
+
+	/**
+	 * Contains all available commands, built using `rebuildCommandList()`
+	 */
+	private HashMap<String, InvokableMethod> commandList;
+
+	/**
+	 * Basic Constructor, automatically rebuilds command list from the modules registry
+	 */
+	public CommandDispatcher()
+	{
+		logger = Logger.getLogger(this.getClass().getName());
+		rebuildCommandList();
+	}
+
+	/**
+	 * Fired when receiving a message
+	 * @param event Event from Discord API
+	 */
+	@EventSubscriber
+	public void onMessageReceivedEvent(MessageReceivedEvent event)
+	{
+		Matcher m = Pattern.compile("^!(\\w+):(\\w+)(?: (.*))?$").matcher(event.getMessage().getContent()); // TODO: Custom command prefix
+		if(!m.matches()) return; // We don't need to go further if it's not even a command
+
+		String module = m.group(1);
+		String command = m.group(2);
+		String fullCommand = module + ":" + command;
+		String[] args = (m.group(3) != null) ? m.group(3).split(" ") : null;
+
+		logger.info("Command invoked (" + event.getMessage().getAuthor().getName() + "): " + fullCommand);
+
+		try
+		{
+			if(commandList.containsKey(fullCommand))
+			{
+				String answer = (String) commandList.get(fullCommand).invoke(new Object[]{args}); // Bricolage
+				if(answer != null) event.getMessage().reply(answer);
+			}
+			else
+				event.getMessage().reply("Unknown command");
+		} catch (MissingPermissionsException | HTTP429Exception | DiscordException e)
+		{
+			logger.warning("Couldn't reply to command: " + e.getMessage());
+		} catch (IllegalArgumentException | IllegalAccessException | InvocationTargetException e)
+		{
+			logger.severe("Couldn't call target method: " + e.getMessage());
+		}
+	}
+
+	/**
+	 * Rebuilds command list using the module registry.
+	 * - It looks for methods with @Command annotation inside class with @Controllable annotation
+	 * - Check his prototype (should be `method(String[]):String`)
+	 * - Add usable methods in his local registry, using InvokableMethod
+	 * @see InvokableMethod
+	 * @see ModulesRegistry
+	 */
+	public void rebuildCommandList()
+	{
+		logger.info("Rebuilding command list...");
+
+		ArrayList<AbstractModule> registry = ModulesRegistry.getRegistry();
+		commandList = new HashMap<>();
+
+		for(AbstractModule i : registry)
+			if(i.getClass().isAnnotationPresent(Controllable.class))
+				for(Method j : i.getClass().getDeclaredMethods())
+					if(j.isAnnotationPresent(Command.class))
+					{
+						String id = i.getClass().getAnnotation(Controllable.class).name() + ":" + j.getName();
+						logger.info("Found " + id);
+
+						if(j.getParameterCount() == 1 && j.getParameterTypes()[0] == String[].class && j.getReturnType() == String.class)
+							commandList.put(id, new InvokableMethod(j, i));
+						else
+							logger.warning(id + ": incorrect function prototype, thus won't be added to the command list.");
+					}
+
+		logger.info("... Done");
+	}
+}

src/main/java/net/pingex/discordbot/Controllable.java

@@ -0,0 +1,21 @@
+package net.pingex.discordbot;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Marks a module as Controllable, ie which contains commands callable from the Discord chat.
+ * @version 0.1-dev
+ * @author Raphael "Pingex" NAAS
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.TYPE)
+public @interface Controllable
+{
+	/**
+	 * Name of the module, ie the `module` part in `!module:command`
+	 */
+	String name();
+}

src/main/java/net/pingex/discordbot/DiscordBot.java

@@ -36,6 +36,7 @@ public class DiscordBot
 				LOGGER.info("Logged in as \"" + event.getClient().getOurUser().getName() + "#" + event.getClient().getOurUser().getDiscriminator() + "\" (#" + event.getClient().getOurUser().getID() + ")"));
 
 		enableModules();
+		this.client.getDispatcher().registerListener(new CommandDispatcher());
 	}
 
 	private void enableModules()

src/main/java/net/pingex/discordbot/IControllable.java

@@ -1,24 +0,0 @@
-package net.pingex.discordbot;
-
-import java.util.Hashtable;
-
-/**
- * Implemented by modules which can be controlled using Discord Commands
- * @version 0.1-dev
- * @author Raphael "Pingex" NAAS
- */
-public interface IControllable
-{
-	/**
-	 * A list of prefixes the module uses to identify itself.
-	 * @return List of prefixes
-	 */
-	String[] getPrefixes();
-
-	/**
-	 * Get a list of shortened commands.
-	 * Example: command !module:myCommand can be shortened as !myc, !mc, or !myco, so the table would be like "myCommand" => ["myc", "mc", "myco"]
-	 * @return Hastable containing all shortened commands. Key is the real command, Value is a list of eligible short commands.
-	 */
-	Hashtable<String, String[]> getShorthands();
-}

src/main/java/net/pingex/discordbot/InvokableMethod.java

@@ -0,0 +1,26 @@
+package net.pingex.discordbot;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+
+/**
+ * Helper class which defines a pair of Method/Object used for direct invoking.
+ * @version 0.1-dev
+ * @author Raphael "Pingex" NAAS
+ */
+public class InvokableMethod
+{
+	public Method method;
+	public Object object;
+
+	public InvokableMethod(Method m, Object o)
+	{
+		method = m;
+		object = o;
+	}
+
+	public Object invoke(Object... args) throws InvocationTargetException, IllegalAccessException, IllegalArgumentException
+	{
+		return method.invoke(object, args);
+	}
+}

src/main/java/net/pingex/discordbot/ModulesRegistry.java

@@ -20,4 +20,14 @@ public class ModulesRegistry
 	{
 		datastore.add(toRegister);
 	}
+
+	/**
+	 * Returns of the whole registry
+	 * @return A clone of the whole registry, to avoid damaging the original registry
+	 */
+	@SuppressWarnings("unchecked")
+	public static ArrayList<AbstractModule> getRegistry()
+	{
+		return (ArrayList<AbstractModule>) datastore.clone();
+	}
 }