package org.lwjgl.input;

import java.util.ArrayList;

import net.java.games.input.ControllerEnvironment;

import org.lwjgl.LWJGLException;

/**
 * The collection of controllers currently connected.
 * 
 * @author Kevin Glass
 */
public class Controllers {
	/** The controllers available */
	private static ArrayList controllers = new ArrayList();
	/** The number of controllers */
	private static int controllerCount;
	
	/** The current list of events */
	private static ArrayList events = new ArrayList();
	/** The current event */
	private static ControllerEvent event;
	
	/** Whether controllers were created */
	private static boolean created;
	
	/**
	 * Initialise the controllers collection
	 * 
	 * @throws LWJGLException Indicates a failure to initialise the controller library.
	 */
	public static void create() throws LWJGLException {
		if (created)
			return;
		
		try {
			ControllerEnvironment env = ControllerEnvironment.getDefaultEnvironment();
			
			net.java.games.input.Controller[] found = env.getControllers();
			ArrayList lollers = new ArrayList();
			for (int i=0;i<found.length;i++) {
				net.java.games.input.Controller c = found[i];
	
				if ((!c.getType().equals(net.java.games.input.Controller.Type.KEYBOARD)) &&
					(!c.getType().equals(net.java.games.input.Controller.Type.MOUSE))) {
					lollers.add(c);
				}
			}
				
			int length = lollers.size();
			
			for (int i=0;i<length;i++) {
				net.java.games.input.Controller c = (net.java.games.input.Controller) lollers.get(i);
	
				createController(c);
			}
			
			created = true;
		} catch (Throwable e) {
			throw new LWJGLException("Failed to initialise controllers",e);
		}
	}
	
	/**
	 * Utility to create a controller based on its potential sub-controllers
	 * 
	 * @param c The controller to add
	 */
	private static void createController(net.java.games.input.Controller c) {
		net.java.games.input.Controller[] sub = c.getControllers();
		if (sub.length == 0) {
			JInputController controller = new JInputController(controllerCount,c);
			
			controllers.add(controller);
			controllerCount++;
		} else {
			for (int i=0;i<sub.length;i++) {
				createController(sub[i]);
			}
		}
	}
	
	/**
	 * Get a controller from the collection
	 * 
	 * @param index The index of the controller to retrieve
	 * @return The controller requested
	 */
	public static Controller getController(int index) {
		return (Controller) controllers.get(index);
	}
	
	/**
	 * Retrieve a count of the number of controllers
	 * 
	 * @return The number of controllers available
	 */
	public static int getControllerCount() {
		return controllers.size();
	}
	
	/**
	 * Poll the controllers available. This will both update their state
	 * and generate events that must be cleared.
	 */
	public static void poll() {
		for (int i=0;i<controllers.size();i++) {
			getController(i).poll();
		}
	}
	
	/**
	 * Clear any events stored for the controllers in this set
	 */
	public static void clearEvents() {
		events.clear();
	}
	
	/**
	 * Move to the next event that has been stored.
	 * 
	 * @return True if there is still an event to process
	 */
	public static boolean next() {
		if (events.size() == 0) {
			event = null;
			return false;
		}
		
		event = (ControllerEvent) events.remove(0);
		
		return event != null;
	}
	
	/**
	 * @return True if Controllers has been created
	 */
	public static boolean isCreated() {
		return created;
	}	
	
	/**
	 * Destroys any resources used by the controllers
	 */
	public static void destroy() {
// 		FIXME! not currently possible to destroy a controller

//		if (!created)
//			return;
//		created = false;
//
//		// nuke each controller
//		for (int i=0;i<controllers.size();i++) {
//			//
//		}
//		
//		// cleanup
//		event = null;
//		events.clear();
//		controllers.clear();
//		controllerCount = 0;
	}
	
	/**
	 * Get the source of the current event
	 * 
	 * @return The source of the current event
	 */
	public static Controller getEventSource() {
		return event.getSource();
	}
	
	/**
	 * Get the index of the control that caused the current event
	 * 
	 * @return The index of the control that cause the current event
	 */
	public static int getEventControlIndex() {
		return event.getControlIndex();
	}
	
	/**
	 * Check if the current event was caused by a button
	 * 
	 * @return True if the current event was caused by a button
	 */
	public static boolean isEventButton() {
		return event.isButton();
	}

	/**
	 * Check if the current event was caused by a axis
	 * 
	 * @return True if the current event was caused by a axis
	 */
	public static boolean isEventAxis() {
		return event.isAxis();
	}
	
	/**
	 * Check if the current event was caused by movement on the x-axis
	 * 
	 * @return True if the current event was cause by movement on the x-axis
	 */
	public static boolean isEventXAxis() {
		return event.isXAxis();
	}

	/**
	 * Check if the current event was caused by movement on the y-axis
	 * 
	 * @return True if the current event was caused by movement on the y-axis
	 */
	public static boolean isEventYAxis() {
		return event.isYAxis();
	}
	
	/**
	 * Check if the current event was cause by the POV x-axis
	 * 
	 * @return True if the current event was caused by the POV x-axis
	 */
	public static boolean isEventPovX() {
		return event.isPovX();
	}
	
	/**
	 * Check if the current event was cause by the POV x-axis
	 * 
	 * @return True if the current event was caused by the POV x-axis
	 */
	public static boolean isEventPovY() {
		return event.isPovY();
	}
	
	/**
	 * Get the timestamp assigned to the current event
	 * 
	 * @return The timestamp assigned ot the current event
	 */
	public static long getEventNanoseconds() {
		return event.getTimeStamp();
	}
	
	/**
	 * Add an event to the stack of events that have been caused
	 * 
	 * @param event The event to add to the list
	 */
	static void addEvent(ControllerEvent event) {
		if (event != null) {
			events.add(event);
		}
	}
}