package org.flixel.system
{
	import org.flixel.FlxObject;
	import org.flixel.FlxTilemap;
	
	/**
	 * A simple helper object for <code>FlxTilemap</code> that helps expand collision opportunities and control.
	 * You can use <code>FlxTilemap.setTileProperties()</code> to alter the collision properties and
	 * callback functions and filters for this object to do things like one-way tiles or whatever.
	 * 
	 * @author	Adam Atomic
	 */
	public class FlxTile extends FlxObject
	{
		/**
		 * This function is called whenever an object hits a tile of this type.
		 * This function should take the form <code>myFunction(Tile:FlxTile,Object:FlxObject):void</code>.
		 * Defaults to null, set through <code>FlxTilemap.setTileProperties()</code>.
		 */
		public var callback:Function;
		/**
		 * Each tile can store its own filter class for their callback functions.
		 * That is, the callback will only be triggered if an object with a class
		 * type matching the filter touched it.
		 * Defaults to null, set through <code>FlxTilemap.setTileProperties()</code>.
		 */
		public var filter:Class;
		/**
		 * A reference to the tilemap this tile object belongs to.
		 */
		public var tilemap:FlxTilemap;
		/**
		 * The index of this tile type in the core map data.
		 * For example, if your map only has 16 kinds of tiles in it,
		 * this number is usually between 0 and 15.
		 */
		public var index:uint;
		/**
		 * The current map index of this tile object at this moment.
		 * You can think of tile objects as moving around the tilemap helping with collisions.
		 * This value is only reliable and useful if used from the callback function.
		 */
		public var mapIndex:uint;
		
		/**
		 * Instantiate this new tile object.  This is usually called from <code>FlxTilemap.loadMap()</code>.
		 * 
		 * @param Tilemap			A reference to the tilemap object creating the tile.
		 * @param Index				The actual core map data index for this tile type.
		 * @param Width				The width of the tile.
		 * @param Height			The height of the tile.
		 * @param Visible			Whether the tile is visible or not.
		 * @param AllowCollisions	The collision flags for the object.  By default this value is ANY or NONE depending on the parameters sent to loadMap().
		 */
		public function FlxTile(Tilemap:FlxTilemap, Index:uint, Width:Number, Height:Number, Visible:Boolean, AllowCollisions:uint)
		{
			super(0, 0, Width, Height);
			immovable = true;
			moves = false;
			callback = null;
			filter = null;
			
			tilemap = Tilemap;
			index = Index;
			visible = Visible;
			allowCollisions = AllowCollisions;
			
			mapIndex = 0;
		}
		
		/**
		 * Clean up memory.
		 */
		override public function destroy():void
		{
			callback = null;
			tilemap = null;
			super.destroy();
		}
	}
}
