/**
*  
* @module Kiwi
* @submodule Renderers
*
* @namespace Kiwi.Renderers
*/

module Kiwi.Renderers {

	/**
	* Wraps a webGL texture object
	* @class GLTextureWrapper
	* @constructor
	* @param gl {WebGLRenderingContext}
	* @param atlas {Kiwi.Textures.TextureAtlas} The wrapper will default to wrapping atlas.image.
	* @return {Kiwi.Renderers.GLTextureWrapper}
	*/
	export class GLTextureWrapper {

		constructor(gl: WebGLRenderingContext, atlas: Kiwi.Textures.TextureAtlas,upload:boolean = false) {
			this.textureAtlas = atlas;
			this._image = atlas.image;
			this._numBytes = this._image.width * this._image.height * 4;
			this.createTexture(gl);
			if (upload) this.uploadTexture(gl);

		}

		/**
		* The textureAtlas used by the GLTexture
		* @property textureAtlas
		* @type Kiwi.Textures.TextureAtlas
		*/

		public textureAtlas: Kiwi.Textures.TextureAtlas;

		/**
		* The number of bytes in the texture
		* @property numBytes
		* @type Kiwi.Textures.TextureAtlas
		*/

		private _numBytes: number;
		public get numBytes(): number {
			return this._numBytes;
		}

		/**
		* Returns whether the texture has been created
		* @property created
		* @type boolean
		*/
		private _created: boolean = false;
		public get created(): boolean {
			return this._created;
		}

		/**
		* Returns whether the texture has been uploaded to video memory
		* @property uploaded
		* @type boolean
		*/
		private _uploaded: boolean = false;
		public get uploaded(): boolean {
			return this._uploaded;
		}

		/**
		*
		* @property texture
		* @type WebGLTexture
		* @public
		*/
		public texture: WebGLTexture;

		/**
		* The image wrapped by this wrapper.
		* @property _image
		* @type HTMLImageElement
		* @private
		*/
		private _image: HTMLImageElement;

		/**
		* The image wrapped by this wrapper.
		* @property image
		* @type HTMLImageElement
		* @public
		*/
		public get image(): HTMLImageElement {
			return( this._image );
		}
		public set image(image: HTMLImageElement) {
			this._image = image;
			this._numBytes = this._image.width * this._image.height * 4;
			this._uploaded = false;
		}


		/**
		* Creates a webgl texture object
		* @method createTexture
		* @param gl {WebGLRenderingContext}
		* @public
		*/
		public createTexture(gl: WebGLRenderingContext): boolean {
			this.texture = gl.createTexture();
			this._created = true;
			return true;
		}


		/**
		* Uploads a webgl texture object to video memory
		* @method uploadTexture
		* @param gl {WebGLRenderingContext}
		* @public
		*/
		public uploadTexture(gl: WebGLRenderingContext):boolean {
			var success: boolean = false;
			if (!this.created) {
				this.createTexture(gl);
			}

			if (this.uploaded) {
				Kiwi.Log.log("...not uploading:the image is already uploaded.", '#renderer', '#webgl'); 
			} else {
				gl.bindTexture(gl.TEXTURE_2D, this.texture);
				gl.pixelStorei(gl.UNPACK_PREMULTIPLY_ALPHA_WEBGL, 0);
				gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, this._image);
				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);
			
				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);
				gl.bindTexture(gl.TEXTURE_2D, null);
				//check gl error here
				this._uploaded = true;
				success = true;
			}

			return success;
		}

		/**
		* Re-uploads a webgl texture object to video memory
		* @method refreshTexture
		* @param gl {WebGLRenderingContext}
		* @public
		*/
		public refreshTexture(gl: WebGLRenderingContext) {
			this.numBytes = this._image.width * this._image.height * 4;
			gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, this._image);
		}

		/**
		* Deletes a webgl texture
		* @method deleteTexture
		* @param gl {WebGLRenderingContext}
		* @public
		*/
		public deleteTexture(gl: WebGLRenderingContext) :boolean{
			gl.deleteTexture(this.texture);
			this._uploaded = false;
			this._created = false;
			return true;
		}

	}

}