/****************************************************************************
 Copyright (c) 2008-2010 Ricardo Quesada
 Copyright (c) 2011-2012 cocos2d-x.org
 Copyright (c) 2013-2014 Chukong Technologies Inc.

 http://www.cocos2d-x.org

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 ****************************************************************************/

/**
 * Canvas of DrawingPrimitive implement version use for WebGlMode
 * @class
 * @extends cc.Class
 */
cc.DrawingPrimitiveWebGL = cc.Class.extend(/** @lends cc.DrawingPrimitiveWebGL# */{
    _renderContext:null,
    _initialized:false,
    _shader: null,
    _colorLocation:-1,
    _colorArray: null,
    _pointSizeLocation:-1,
    _pointSize:-1,
    /**
     * contructor of cc.DrawingPrimitiveWebGL
     * @param ctx rendercontext
     */
    ctor:function (ctx) {
        if (ctx == null)
            ctx = cc._renderContext;

        if (!ctx instanceof  WebGLRenderingContext)
            throw "Can't initialise DrawingPrimitiveWebGL. context need is WebGLRenderingContext";

        this._renderContext = ctx;
        this._colorArray = new Float32Array([1.0, 1.0, 1.0, 1.0]);
    },

    lazy_init:function () {
        var _t = this;
        if (!_t._initialized) {
            //
            // Position and 1 color passed as a uniform (to similate glColor4ub )
            //
            _t._shader = cc.shaderCache.programForKey(cc.SHADER_POSITION_UCOLOR);
            _t._colorLocation = _t._renderContext.getUniformLocation(_t._shader.getProgram(), "u_color");
            _t._pointSizeLocation = _t._renderContext.getUniformLocation(_t._shader.getProgram(), "u_pointSize");

            _t._initialized = true;
        }
    },

    /**
     * initlialize context
     */
    drawInit:function () {
        this._initialized = false;
    },

    /**
     * draws a point given x and y coordinate measured in points
     * @param {cc.Point} point
     */
    drawPoint:function (point) {
        this.lazy_init();

        var glContext = this._renderContext;
        this._shader.use();
        this._shader.setUniformForModelViewAndProjectionMatrixWithMat4();
        cc.glEnableVertexAttribs(cc.VERTEX_ATTRIB_FLAG_POSITION);
        glContext.uniform4fv(this._colorLocation, this._colorArray);
        this._shader.setUniformLocationWith1f(this._pointSizeLocation, this._pointSize);

        var pointBuffer = glContext.createBuffer();
        glContext.bindBuffer(glContext.ARRAY_BUFFER, pointBuffer);
        glContext.bufferData(glContext.ARRAY_BUFFER, new Float32Array([point.x, point.y]), glContext.STATIC_DRAW);
        glContext.vertexAttribPointer(cc.VERTEX_ATTRIB_POSITION, 2, glContext.FLOAT, false, 0, 0);

        glContext.drawArrays(glContext.POINTS, 0, 1);
        glContext.deleteBuffer(pointBuffer);

        cc.incrementGLDraws(1);
    },

    /**
     * draws an array of points.
     * @param {Array} points point of array
     * @param {Number} numberOfPoints
     */
    drawPoints:function (points, numberOfPoints) {
        if (!points || points.length == 0)
            return;

        this.lazy_init();

        var glContext = this._renderContext;
        this._shader.use();
        this._shader.setUniformForModelViewAndProjectionMatrixWithMat4();
        cc.glEnableVertexAttribs(cc.VERTEX_ATTRIB_FLAG_POSITION);
        glContext.uniform4fv(this._colorLocation, this._colorArray);
        this._shader.setUniformLocationWith1f(this._pointSizeLocation, this._pointSize);

        var pointBuffer = glContext.createBuffer();
        glContext.bindBuffer(glContext.ARRAY_BUFFER, pointBuffer);
        glContext.bufferData(glContext.ARRAY_BUFFER, this._pointsToTypeArray(points), glContext.STATIC_DRAW);
        glContext.vertexAttribPointer(cc.VERTEX_ATTRIB_POSITION, 2, glContext.FLOAT, false, 0, 0);

        glContext.drawArrays(glContext.POINTS, 0, points.length);
        glContext.deleteBuffer(pointBuffer);

        cc.incrementGLDraws(1);
    },

    _pointsToTypeArray:function (points) {
        var typeArr = new Float32Array(points.length * 2);
        for (var i = 0; i < points.length; i++) {
            typeArr[i * 2] = points[i].x;
            typeArr[i * 2 + 1] = points[i].y;
        }
        return typeArr;
    },

    /**
     * draws a line given the origin and destination point measured in points
     * @param {cc.Point} origin
     * @param {cc.Point} destination
     */
    drawLine:function (origin, destination) {
        this.lazy_init();

        var glContext = this._renderContext;
        this._shader.use();
        this._shader.setUniformForModelViewAndProjectionMatrixWithMat4();
        cc.glEnableVertexAttribs(cc.VERTEX_ATTRIB_FLAG_POSITION);
        glContext.uniform4fv(this._colorLocation, this._colorArray);

        var pointBuffer = glContext.createBuffer();
        glContext.bindBuffer(glContext.ARRAY_BUFFER, pointBuffer);
        glContext.bufferData(glContext.ARRAY_BUFFER, this._pointsToTypeArray([origin, destination]), glContext.STATIC_DRAW);
        glContext.vertexAttribPointer(cc.VERTEX_ATTRIB_POSITION, 2, glContext.FLOAT, false, 0, 0);

        glContext.drawArrays(glContext.LINES, 0, 2);
        glContext.deleteBuffer(pointBuffer);

        cc.incrementGLDraws(1);
    },

    /**
     * draws a rectangle given the origin and destination point measured in points.
     * @param {cc.Point} origin
     * @param {cc.Point} destination
     */
    drawRect:function (origin, destination) {
        this.drawLine(cc.p(origin.x, origin.y), cc.p(destination.x, origin.y));
        this.drawLine(cc.p(destination.x, origin.y), cc.p(destination.x, destination.y));
        this.drawLine(cc.p(destination.x, destination.y), cc.p(origin.x, destination.y));
        this.drawLine(cc.p(origin.x, destination.y), cc.p(origin.x, origin.y));
    },

    /**
     * draws a solid rectangle given the origin and destination point measured in points.
     * @param {cc.Point} origin
     * @param {cc.Point} destination
     * @param {cc.Color} color
     */
    drawSolidRect:function (origin, destination, color) {
        var vertices = [
            origin,
            cc.p(destination.x, origin.y),
            destination,
            cc.p(origin.x, destination.y)
        ];

        this.drawSolidPoly(vertices, 4, color);
    },

    /**
     * draws a polygon given a pointer to cc.Point coordiantes and the number of vertices measured in points.
     * @param {Array} vertices a pointer to cc.Point coordiantes
     * @param {Number} numOfVertices the number of vertices measured in points
     * @param {Boolean} closePolygon The polygon can be closed or open
     */
    drawPoly:function (vertices, numOfVertices, closePolygon) {
        this.lazy_init();

        var glContext = this._renderContext;
        this._shader.use();
        this._shader.setUniformForModelViewAndProjectionMatrixWithMat4();
        cc.glEnableVertexAttribs(cc.VERTEX_ATTRIB_FLAG_POSITION);
        glContext.uniform4fv(this._colorLocation, this._colorArray);

        var pointBuffer = glContext.createBuffer();
        glContext.bindBuffer(glContext.ARRAY_BUFFER, pointBuffer);
        glContext.bufferData(glContext.ARRAY_BUFFER, this._pointsToTypeArray(vertices), glContext.STATIC_DRAW);
        glContext.vertexAttribPointer(cc.VERTEX_ATTRIB_POSITION, 2, glContext.FLOAT, false, 0, 0);

        if (closePolygon)
            glContext.drawArrays(glContext.LINE_LOOP, 0, vertices.length);
        else
            glContext.drawArrays(glContext.LINE_STRIP, 0, vertices.length);
        glContext.deleteBuffer(pointBuffer);

        cc.incrementGLDraws(1);
    },

    /**
     * draws a solid polygon given a pointer to CGPoint coordiantes, the number of vertices measured in points, and a color.
     * @param {Array} poli
     * @param {Number} numberOfPoints
     * @param {cc.Color} color
     */
    drawSolidPoly:function (poli, numberOfPoints, color) {
        this.lazy_init();
        if (color)
            this.setDrawColor(color.r, color.g, color.b, color.a);

        var glContext = this._renderContext;
        this._shader.use();
        this._shader.setUniformForModelViewAndProjectionMatrixWithMat4();
        cc.glEnableVertexAttribs(cc.VERTEX_ATTRIB_FLAG_POSITION);
        glContext.uniform4fv(this._colorLocation, this._colorArray);

        var pointBuffer = glContext.createBuffer();
        glContext.bindBuffer(glContext.ARRAY_BUFFER, pointBuffer);
        glContext.bufferData(glContext.ARRAY_BUFFER, this._pointsToTypeArray(poli), glContext.STATIC_DRAW);
        glContext.vertexAttribPointer(cc.VERTEX_ATTRIB_POSITION, 2, glContext.FLOAT, false, 0, 0);
        glContext.drawArrays(glContext.TRIANGLE_FAN, 0, poli.length);
        glContext.deleteBuffer(pointBuffer);

        cc.incrementGLDraws(1);
    },

    /**
     * draws a circle given the center, radius and number of segments.
     * @param {cc.Point} center center of circle
     * @param {Number} radius
     * @param {Number} angle angle in radians
     * @param {Number} segments
     * @param {Boolean} drawLineToCenter
     */
    drawCircle:function (center, radius, angle, segments, drawLineToCenter) {
        this.lazy_init();

        var additionalSegment = 1;
        if (drawLineToCenter)
            additionalSegment++;

        var coef = 2.0 * Math.PI / segments;

        var vertices = new Float32Array((segments + 2) * 2);
        if (!vertices)
            return;

        for (var i = 0; i <= segments; i++) {
            var rads = i * coef;
            var j = radius * Math.cos(rads + angle) + center.x;
            var k = radius * Math.sin(rads + angle) + center.y;

            vertices[i * 2] = j;
            vertices[i * 2 + 1] = k;
        }
        vertices[(segments + 1) * 2] = center.x;
        vertices[(segments + 1) * 2 + 1] = center.y;

        var glContext = this._renderContext;
        this._shader.use();
        this._shader.setUniformForModelViewAndProjectionMatrixWithMat4();
        cc.glEnableVertexAttribs(cc.VERTEX_ATTRIB_FLAG_POSITION);
        glContext.uniform4fv(this._colorLocation, this._colorArray);

        var pointBuffer = glContext.createBuffer();
        glContext.bindBuffer(glContext.ARRAY_BUFFER, pointBuffer);
        glContext.bufferData(glContext.ARRAY_BUFFER, vertices, glContext.STATIC_DRAW);
        glContext.vertexAttribPointer(cc.VERTEX_ATTRIB_POSITION, 2, glContext.FLOAT, false, 0, 0);

        glContext.drawArrays(glContext.LINE_STRIP, 0, segments + additionalSegment);
        glContext.deleteBuffer(pointBuffer);

        cc.incrementGLDraws(1);
    },

    /**
     * draws a quad bezier path
     * @param {cc.Point} origin
     * @param {cc.Point} control
     * @param {cc.Point} destination
     * @param {Number} segments
     */
    drawQuadBezier:function (origin, control, destination, segments) {
        this.lazy_init();

        var vertices = new Float32Array((segments + 1) * 2);

        var t = 0.0;
        for (var i = 0; i < segments; i++) {
            vertices[i * 2] = Math.pow(1 - t, 2) * origin.x + 2.0 * (1 - t) * t * control.x + t * t * destination.x;
            vertices[i * 2 + 1] = Math.pow(1 - t, 2) * origin.y + 2.0 * (1 - t) * t * control.y + t * t * destination.y;
            t += 1.0 / segments;
        }
        vertices[segments * 2] = destination.x;
        vertices[segments * 2 + 1] = destination.y;

        var glContext = this._renderContext;
        this._shader.use();
        this._shader.setUniformForModelViewAndProjectionMatrixWithMat4();
        cc.glEnableVertexAttribs(cc.VERTEX_ATTRIB_FLAG_POSITION);
        glContext.uniform4fv(this._colorLocation, this._colorArray);

        var pointBuffer = glContext.createBuffer();
        glContext.bindBuffer(glContext.ARRAY_BUFFER, pointBuffer);
        glContext.bufferData(glContext.ARRAY_BUFFER, vertices, glContext.STATIC_DRAW);
        glContext.vertexAttribPointer(cc.VERTEX_ATTRIB_POSITION, 2, glContext.FLOAT, false, 0, 0);

        glContext.drawArrays(glContext.LINE_STRIP, 0, segments + 1);
        glContext.deleteBuffer(pointBuffer);

        cc.incrementGLDraws(1);
    },

    /**
     * draws a cubic bezier path
     * @param {cc.Point} origin
     * @param {cc.Point} control1
     * @param {cc.Point} control2
     * @param {cc.Point} destination
     * @param {Number} segments
     */
    drawCubicBezier:function (origin, control1, control2, destination, segments) {
        this.lazy_init();

        var vertices = new Float32Array((segments + 1) * 2);

        var t = 0;
        for (var i = 0; i < segments; i++) {
            vertices[i * 2] = Math.pow(1 - t, 3) * origin.x + 3.0 * Math.pow(1 - t, 2) * t * control1.x + 3.0 * (1 - t) * t * t * control2.x + t * t * t * destination.x;
            vertices[i * 2 + 1] = Math.pow(1 - t, 3) * origin.y + 3.0 * Math.pow(1 - t, 2) * t * control1.y + 3.0 * (1 - t) * t * t * control2.y + t * t * t * destination.y;
            t += 1.0 / segments;
        }
        vertices[segments * 2] = destination.x;
        vertices[segments * 2 + 1] = destination.y;

        var glContext = this._renderContext;
        this._shader.use();
        this._shader.setUniformForModelViewAndProjectionMatrixWithMat4();
        cc.glEnableVertexAttribs(cc.VERTEX_ATTRIB_FLAG_POSITION);
        glContext.uniform4fv(this._colorLocation, this._colorArray);

        var pointBuffer = glContext.createBuffer();
        glContext.bindBuffer(glContext.ARRAY_BUFFER, pointBuffer);
        glContext.bufferData(glContext.ARRAY_BUFFER, vertices, glContext.STATIC_DRAW);
        glContext.vertexAttribPointer(cc.VERTEX_ATTRIB_POSITION, 2, glContext.FLOAT, false, 0, 0);
        glContext.drawArrays(glContext.LINE_STRIP, 0, segments + 1);
        glContext.deleteBuffer(pointBuffer);

        cc.incrementGLDraws(1);
    },

    /**
     * draw a catmull rom line
     * @param {Array} points
     * @param {Number} segments
     */
    drawCatmullRom:function (points, segments) {
        this.drawCardinalSpline(points, 0.5, segments);
    },

    /**
     * draw a cardinal spline path
     * @param {Array} config
     * @param {Number} tension
     * @param {Number} segments
     */
    drawCardinalSpline:function (config, tension, segments) {
        this.lazy_init();

        var vertices = new Float32Array((segments + 1) * 2);
        var p, lt, deltaT = 1.0 / config.length;
        for (var i = 0; i < segments + 1; i++) {
            var dt = i / segments;

            // border
            if (dt == 1) {
                p = config.length - 1;
                lt = 1;
            } else {
                p = 0 | (dt / deltaT);
                lt = (dt - deltaT * p) / deltaT;
            }

            var newPos = cc.CardinalSplineAt(
                cc.getControlPointAt(config, p - 1),
                cc.getControlPointAt(config, p),
                cc.getControlPointAt(config, p + 1),
                cc.getControlPointAt(config, p + 2),
                tension, lt);
            // Interpolate

            vertices[i * 2] = newPos.x;
            vertices[i * 2 + 1] = newPos.y;
        }

        var glContext = this._renderContext;
        this._shader.use();
        this._shader.setUniformForModelViewAndProjectionMatrixWithMat4();
        cc.glEnableVertexAttribs(cc.VERTEX_ATTRIB_FLAG_POSITION);
        glContext.uniform4fv(this._colorLocation, this._colorArray);

        var pointBuffer = glContext.createBuffer();
        glContext.bindBuffer(glContext.ARRAY_BUFFER, pointBuffer);
        glContext.bufferData(glContext.ARRAY_BUFFER, vertices, glContext.STATIC_DRAW);
        glContext.vertexAttribPointer(cc.VERTEX_ATTRIB_POSITION, 2, glContext.FLOAT, false, 0, 0);
        glContext.drawArrays(glContext.LINE_STRIP, 0, segments + 1);
        glContext.deleteBuffer(pointBuffer);

        cc.incrementGLDraws(1);
    },

    /**
     * set the drawing color with 4 unsigned bytes
     * @param {Number} r red value (0 to 255)
     * @param {Number} g green value (0 to 255)
     * @param {Number} b blue value (0 to 255)
     * @param {Number} a Alpha value (0 to 255)
     */
    setDrawColor:function (r, g, b, a) {
        this._colorArray[0] = r / 255.0;
        this._colorArray[1] = g / 255.0;
        this._colorArray[2] = b / 255.0;
        this._colorArray[3] = a / 255.0;
    },

    /**
     * set the point size in points. Default 1.
     * @param {Number} pointSize
     */
    setPointSize:function (pointSize) {
        this._pointSize = pointSize * cc.contentScaleFactor();
    },

    /**
     * set the line width. Default 1.
     * @param {Number} width
     */
    setLineWidth:function (width) {
        if(this._renderContext.lineWidth)
            this._renderContext.lineWidth(width);
    }
});