/**
 * @author Mat Groves http://matgroves.com/ @Doormat23
 */

/**
 * A RenderTexture is a special texture that allows any pixi displayObject to be rendered to it. 
 * @class RenderTexture
 * @extends Texture
 * @constructor
 * @param width {Number}
 * @param height {Number}
 */
PIXI.RenderTexture = function(width, height)
{
	PIXI.EventTarget.call( this );
	
	this.width = width || 100;
	this.height = height || 100;

	this.indetityMatrix = PIXI.mat3.create();
	
	this.frame = new PIXI.Rectangle(0, 0, this.width, this.height);	
	
	if(PIXI.gl)
	{
		this.initWebGL();
	}
	else
	{
		this.initCanvas();
	}
}

PIXI.RenderTexture.constructor = PIXI.RenderTexture;
PIXI.RenderTexture.prototype = Object.create( PIXI.Texture.prototype );

PIXI.RenderTexture.prototype.initWebGL = function()
{
	var gl = PIXI.gl;
	this.glFramebuffer = gl.createFramebuffer();
	
   	gl.bindFramebuffer(gl.FRAMEBUFFER, this.glFramebuffer );

    this.glFramebuffer.width = this.width;
    this.glFramebuffer.height = this.height;	
  
	this.baseTexture = new PIXI.BaseTexture();

	this.baseTexture.width = this.width;
	this.baseTexture.height = this.height;

    this.baseTexture._glTexture = gl.createTexture();
    gl.bindTexture(gl.TEXTURE_2D, this.baseTexture._glTexture);
	 	
	gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA,  this.width,  this.height, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);
	
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
	
	this.baseTexture.isRender = true;
	
	gl.bindFramebuffer(gl.FRAMEBUFFER, this.glFramebuffer );
	gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, this.baseTexture._glTexture, 0);
	
	// create a projection matrix..
	this.projection = new PIXI.Point(this.width/2 , this.height/2);
	
	this.projectionMatrix =  PIXI.mat4.create();
	
	this.projectionMatrix[5] = 2/this.height// * 0.5;
	this.projectionMatrix[13] = -1;
	
	this.projectionMatrix[0] = 2/this.width;
	this.projectionMatrix[12] = -1;

	// set the correct render function..
	this.render = this.renderWebGL;
}

PIXI.RenderTexture.prototype.initCanvas = function()
{
	this.renderer = new PIXI.CanvasRenderer(this.width, this.height, null, 0);
	
	this.baseTexture = new PIXI.BaseTexture(this.renderer.view);
	this.frame = new PIXI.Rectangle(0, 0, this.width, this.height);
	
	this.render = this.renderCanvas;
}

/**
 * This function will draw the display object to the texture.
 * @method render
 * @param displayObject {DisplayObject}
 * @param clear {Boolean} If true the texture will be cleared before the displayObject is drawn
 */
PIXI.RenderTexture.prototype.renderWebGL = function(displayObject, clear)
{
	var gl = PIXI.gl;
	
	// enable the alpha color mask..
	gl.colorMask(true, true, true, true); 
	
	gl.viewport(0, 0, this.width, this.height);	
	
	gl.bindFramebuffer(gl.FRAMEBUFFER, this.glFramebuffer );
	
	if(clear)
	{
		gl.clearColor(0,0,0, 0);     
		gl.clear(gl.COLOR_BUFFER_BIT);
	}
	
	// THIS WILL MESS WITH HIT TESTING!
	var children = displayObject.children;
	
	//TODO -? create a new one??? dont think so!
	displayObject.worldTransform = PIXI.mat3.create();//sthis.indetityMatrix;
	// modify to flip...
	displayObject.worldTransform[4] = -1;
	displayObject.worldTransform[5] = this.projection.y * 2;
	
	for(var i=0,j=children.length; i<j; i++)
	{
		children[i].updateTransform();	
	}
	
	var renderGroup = displayObject.__renderGroup;

	if(renderGroup)
	{
		if(displayObject == renderGroup.root)
		{
			renderGroup.render(this.projection);
		}
		else
		{
			renderGroup.renderSpecific(displayObject, this.projection);
		}
	}
	else
	{
		if(!this.renderGroup)this.renderGroup = new PIXI.WebGLRenderGroup(gl);
		this.renderGroup.setRenderable(displayObject);
		this.renderGroup.render(this.projection);
	}
	
}

PIXI.RenderTexture.prototype.renderCanvas = function(displayObject, clear)
{
	var children = displayObject.children;
	
	displayObject.worldTransform = PIXI.mat3.create();
	
	for(var i=0,j=children.length; i<j; i++)
	{
		children[i].updateTransform();	
	}

	if(clear)this.renderer.context.clearRect(0,0, this.width, this.height);
    this.renderer.renderDisplayObject(displayObject);
    
    PIXI.texturesToUpdate.push(this.baseTexture);
}