/**
 * Loader for CTM encoded models generated by OpenCTM tools:
 *	http://openctm.sourceforge.net/
 *
 * Uses js-openctm library by Juan Mellado
 *	http://code.google.com/p/js-openctm/
 *
 * @author alteredq / http://alteredqualia.com/
 */

THREE.CTMLoader = function ( ) {

};

THREE.CTMLoader.prototype = new THREE.CTMLoader();
THREE.CTMLoader.prototype.constructor = THREE.CTMLoader;


// Load CTMLoader compressed models
//  - parameters
//		- url (required)
//		- callback (required)

THREE.CTMLoader.prototype.load = function( url, callback, useWorker ) {

	var xhr = new XMLHttpRequest(),
		callbackProgress = null;

	var length = 0;

	xhr.onreadystatechange = function() {

		if ( xhr.readyState == 4 ) {

			if ( xhr.status == 200 || xhr.status == 0 ) {

				var binaryData = xhr.responseText;

				var s = Date.now();

				if ( useWorker ) {

					var worker = new Worker( "js/ctm/CTMWorker.js" );

					worker.onmessage = function( event ) {

						var ctmFile = event.data;
						THREE.CTMLoader.prototype.createModel( ctmFile, callback );

						var e = Date.now();
						console.log( "CTM data parse time [worker]: " + (e-s) + " ms" );

					};

					worker.postMessage( binaryData );

				} else {

					var ctmFile = new CTM.File( new CTM.Stream( binaryData ) );
					THREE.CTMLoader.prototype.createModel( ctmFile, callback );

					var e = Date.now();
					console.log( "CTM data parse time [inline]: " + (e-s) + " ms" );

				}

			} else {

				console.error( "Couldn't load [" + url + "] [" + xhr.status + "]" );

			}

		} else if ( xhr.readyState == 3 ) {

			if ( callbackProgress ) {

				if ( length == 0 ) {

					length = xhr.getResponseHeader( "Content-Length" );

				}

				callbackProgress( { total: length, loaded: xhr.responseText.length } );

			}

		} else if ( xhr.readyState == 2 ) {

			length = xhr.getResponseHeader( "Content-Length" );

		}

	}

	xhr.overrideMimeType( "text/plain; charset=x-user-defined" );
	xhr.open( "GET", url, true );
	xhr.send( null );

};


THREE.CTMLoader.prototype.createModel = function ( file, callback ) {

	var Model = function ( texture_path ) {

		var scope = this;

		scope.materials = [];

		THREE.Geometry.call( this );

		var normals = [],
			uvs = [],
			colors = [];

		init_vertices( file.body.vertices );

		if ( file.body.normals !== undefined )
			init_normals( file.body.normals );

		if ( file.body.uvMaps !== undefined && file.body.uvMaps.length > 0 )
			init_uvs( file.body.uvMaps[ 0 ].uv );

		if ( file.body.attrMaps !== undefined && file.body.attrMaps.length > 0 && file.body.attrMaps[ 0 ].name === "Color" )
			init_colors( file.body.attrMaps[ 0 ].attr );

		var hasNormals = normals.length > 0 ? true : false,
			hasUvs = uvs.length > 0 ? true : false,
			hasColors = colors.length > 0 ? true : false;

		init_faces( file.body.indices );

		this.computeCentroids();
		this.computeFaceNormals();
		//this.computeTangents();

		function init_vertices( buffer ) {

			var x, y, z, i, il = buffer.length;

			for( i = 0; i < il; i += 3 ) {

				x = buffer[ i ];
				y = buffer[ i + 1 ];
				z = buffer[ i + 2 ];

				vertex( scope, x, y, z );

			}

		};

		function init_normals( buffer ) {

			var x, y, z, i, il = buffer.length;

			for( i = 0; i < il; i += 3 ) {

				x = buffer[ i ];
				y = buffer[ i + 1 ];
				z = buffer[ i + 2 ];

				normals.push( x, y, z );

			}

		};

		function init_colors( buffer ) {

			var r, g, b, a, i, il = buffer.length;

			for( i = 0; i < il; i += 4 ) {

				r = buffer[ i ];
				g = buffer[ i + 1 ];
				b = buffer[ i + 2 ];
				a = buffer[ i + 3 ];

				var color = new THREE.Color();
				color.setRGB( r, g, b );

				colors.push( color );

			}

		};


		function init_uvs( buffer ) {

			var u, v, i, il = buffer.length;

			for( i = 0; i < il; i += 2 ) {

				u = buffer[ i ];
				v = buffer[ i + 1 ];

				uvs.push( u, 1 - v );

			}

		};

		function init_faces( buffer ) {

			var a, b, c,
				u1, v1, u2, v2, u3, v3,
				m, face,
				i, il = buffer.length;

			m = 0; // all faces defaulting to material 0

			for( i = 0; i < il; i += 3 ) {

				a = buffer[ i ];
				b = buffer[ i + 1 ];
				c = buffer[ i + 2 ];

				if ( hasNormals )
					face = f3n( scope, normals, a, b, c, m, a, b, c );
				else
					face = f3( scope, a, b, c, m );

				if ( hasColors ) {

					face.vertexColors[ 0 ] = colors[ a ];
					face.vertexColors[ 1 ] = colors[ b ];
					face.vertexColors[ 2 ] = colors[ c ];

				}

				if ( hasUvs ) {

					u1 = uvs[ a * 2 ];
					v1 = uvs[ a * 2 + 1 ];

					u2 = uvs[ b * 2 ];
					v2 = uvs[ b * 2 + 1 ];

					u3 = uvs[ c * 2 ];
					v3 = uvs[ c * 2 + 1 ];

					uv3( scope.faceVertexUvs[ 0 ], u1, v1, u2, v2, u3, v3 );

				}

			}

		}

	};

	function vertex ( scope, x, y, z ) {

		scope.vertices.push( new THREE.Vertex( new THREE.Vector3( x, y, z ) ) );

	};

	function f3 ( scope, a, b, c, mi ) {

		var face = new THREE.Face3( a, b, c, null, null, mi );

		scope.faces.push( face );

		return face;

	};

	function f3n ( scope, normals, a, b, c, mi, na, nb, nc ) {

		var nax = normals[ na * 3     ],
			nay = normals[ na * 3 + 1 ],
			naz = normals[ na * 3 + 2 ],

			nbx = normals[ nb * 3     ],
			nby = normals[ nb * 3 + 1 ],
			nbz = normals[ nb * 3 + 2 ],

			ncx = normals[ nc * 3     ],
			ncy = normals[ nc * 3 + 1 ],
			ncz = normals[ nc * 3 + 2 ];

		var na = new THREE.Vector3( nax, nay, naz ),
			nb = new THREE.Vector3( nbx, nby, nbz ),
			nc = new THREE.Vector3( ncx, ncy, ncz );

		var face = new THREE.Face3( a, b, c, [ na, nb, nc ], null, mi );

		scope.faces.push( face );

		return face;

	};

	function uv3 ( where, u1, v1, u2, v2, u3, v3 ) {

		var uv = [];
		uv.push( new THREE.UV( u1, v1 ) );
		uv.push( new THREE.UV( u2, v2 ) );
		uv.push( new THREE.UV( u3, v3 ) );
		where.push( uv );

	};

	Model.prototype = new THREE.Geometry();
	Model.prototype.constructor = Model;

	callback( new Model() );

};