(function() {
    'use strict';
    /**
     * Sprite constructor
     * @constructor
     * @memberof Konva
     * @augments Konva.Shape
     * @param {Object} config
     * @param {String} config.animation animation key
     * @param {Object} config.animations animation map
     * @param {Integer} [config.frameIndex] animation frame index
     * @param {Image} config.image image object
     * @@shapeParams
     * @@nodeParams
     * @example
     * var imageObj = new Image();
     * imageObj.onload = function() {
     *   var sprite = new Konva.Sprite({
     *     x: 200,
     *     y: 100,
     *     image: imageObj,
     *     animation: 'standing',
     *     animations: {
     *       standing: [
     *         // x, y, width, height (6 frames)
     *         0, 0, 49, 109,
     *         52, 0, 49, 109,
     *         105, 0, 49, 109,
     *         158, 0, 49, 109,
     *         210, 0, 49, 109,
     *         262, 0, 49, 109
     *       ],
     *       kicking: [
     *         // x, y, width, height (6 frames)
     *         0, 109, 45, 98,
     *         45, 109, 45, 98,
     *         95, 109, 63, 98,
     *         156, 109, 70, 98,
     *         229, 109, 60, 98,
     *         287, 109, 41, 98
     *       ]
     *     },
     *     frameRate: 7,
     *     frameIndex: 0
     *   });
     * };
     * imageObj.src = '/path/to/image.jpg'
     */
    Konva.Sprite = function(config) {
        this.___init(config);
    };

    Konva.Sprite.prototype = {
        ___init: function(config) {
            // call super constructor
            Konva.Shape.call(this, config);
            this.className = 'Sprite';

            this._updated = true;
            var that = this;
            this.anim = new Konva.Animation(function() {
                // if we don't need to redraw layer we should return false
                var updated = that._updated;
                that._updated = false;
                return updated;
            });
            this.on('animationChange.konva', function() {
                // reset index when animation changes
                this.frameIndex(0);
            });
            this.on('frameIndexChange.konva', function() {
                this._updated = true;
            });
            // smooth change for frameRate
            this.on('frameRateChange.konva', function() {
                if (!this.anim.isRunning()) {
                    return;
                }
                clearInterval(this.interval);
                this._setInterval();
            });

            this.sceneFunc(this._sceneFunc);
            this.hitFunc(this._hitFunc);
        },
        _sceneFunc: function(context) {
            var anim = this.getAnimation(),
                index = this.frameIndex(),
                ix4 = index * 4,
                set = this.getAnimations()[anim],
                offsets = this.frameOffsets(),
                x = set[ix4 + 0],
                y = set[ix4 + 1],
                width = set[ix4 + 2],
                height = set[ix4 + 3],
                image = this.getImage();

            if (this.hasFill() || this.hasStroke()) {
                context.beginPath();
                context.rect(0, 0, width, height);
                context.closePath();
                context.fillStrokeShape(this);
            }

            if(image) {
                if (offsets) {
                    var offset = offsets[anim],
                    ix2 = index * 2;
                    context.drawImage(image, x, y, width, height, offset[ix2 + 0], offset[ix2 + 1], width, height);
                } else {
                    context.drawImage(image, x, y, width, height, 0, 0, width, height);
                }
            }
        },
        _hitFunc: function(context) {
            var anim = this.getAnimation(),
                index = this.frameIndex(),
                ix4 = index * 4,
                set = this.getAnimations()[anim],
                offsets = this.frameOffsets(),
                width = set[ix4 + 2],
                height = set[ix4 + 3];

            context.beginPath();
            if (offsets) {
                var offset = offsets[anim];
                var ix2 = index * 2;
                context.rect(offset[ix2 + 0], offset[ix2 + 1], width, height);
            } else {
                context.rect(0, 0, width, height);
            }
            context.closePath();
            context.fillShape(this);
        },
        _useBufferCanvas: function() {
            return (this.hasShadow() || this.getAbsoluteOpacity() !== 1) && this.hasStroke();
        },
        _setInterval: function() {
            var that = this;
            this.interval = setInterval(function() {
                that._updateIndex();
            }, 1000 / this.getFrameRate());
        },
        /**
         * start sprite animation
         * @method
         * @memberof Konva.Sprite.prototype
         */
        start: function() {
            var layer = this.getLayer();

            /*
             * animation object has no executable function because
             *  the updates are done with a fixed FPS with the setInterval
             *  below.  The anim object only needs the layer reference for
             *  redraw
             */
            this.anim.setLayers(layer);
            this._setInterval();
            this.anim.start();
        },
        /**
         * stop sprite animation
         * @method
         * @memberof Konva.Sprite.prototype
         */
        stop: function() {
            this.anim.stop();
            clearInterval(this.interval);
        },
        /**
         * determine if animation of sprite is running or not.  returns true or false
         * @method
         * @memberof Konva.Animation.prototype
         * @returns {Boolean}
         */
        isRunning: function() {
            return this.anim.isRunning();
        },
        _updateIndex: function() {
            var index = this.frameIndex(),
                animation = this.getAnimation(),
                animations = this.getAnimations(),
                anim = animations[animation],
                len = anim.length / 4;

            if(index < len - 1) {
                this.frameIndex(index + 1);
            }
            else {
                this.frameIndex(0);
            }
        }
    };
    Konva.Util.extend(Konva.Sprite, Konva.Shape);

    // add getters setters
    Konva.Factory.addGetterSetter(Konva.Sprite, 'animation');

    /**
     * get/set animation key
     * @name animation
     * @method
     * @memberof Konva.Sprite.prototype
     * @param {String} anim animation key
     * @returns {String}
     * @example
     * // get animation key
     * var animation = sprite.animation();
     *
     * // set animation key
     * sprite.animation('kicking');
     */

    Konva.Factory.addGetterSetter(Konva.Sprite, 'animations');

    /**
     * get/set animations map
     * @name animations
     * @method
     * @memberof Konva.Sprite.prototype
     * @param {Object} animations
     * @returns {Object}
     * @example
     * // get animations map
     * var animations = sprite.animations();
     *
     * // set animations map
     * sprite.animations({
     *   standing: [
     *     // x, y, width, height (6 frames)
     *     0, 0, 49, 109,
     *     52, 0, 49, 109,
     *     105, 0, 49, 109,
     *     158, 0, 49, 109,
     *     210, 0, 49, 109,
     *     262, 0, 49, 109
     *   ],
     *   kicking: [
     *     // x, y, width, height (6 frames)
     *     0, 109, 45, 98,
     *     45, 109, 45, 98,
     *     95, 109, 63, 98,
     *     156, 109, 70, 98,
     *     229, 109, 60, 98,
     *     287, 109, 41, 98
     *   ]
     * });
     */

    Konva.Factory.addGetterSetter(Konva.Sprite, 'frameOffsets');

    /**
    * get/set offsets map
    * @name offsets
    * @method
    * @memberof Konva.Sprite.prototype
    * @param {Object} offsets
    * @returns {Object}
    * @example
    * // get offsets map
    * var offsets = sprite.offsets();
    *
    * // set offsets map
    * sprite.offsets({
    *   standing: [
    *     // x, y (6 frames)
    *     0, 0,
    *     0, 0,
    *     5, 0,
    *     0, 0,
    *     0, 3,
    *     2, 0
    *   ],
    *   kicking: [
    *     // x, y (6 frames)
    *     0, 5,
    *     5, 0,
    *     10, 0,
    *     0, 0,
    *     2, 1,
    *     0, 0
    *   ]
    * });
    */

    Konva.Factory.addGetterSetter(Konva.Sprite, 'image');

    /**
     * get/set image
     * @name image
     * @method
     * @memberof Konva.Sprite.prototype
     * @param {Image} image
     * @returns {Image}
     * @example
     * // get image
     * var image = sprite.image();
     *
     * // set image
     * sprite.image(imageObj);
     */

    Konva.Factory.addGetterSetter(Konva.Sprite, 'frameIndex', 0);

    /**
     * set/set animation frame index
     * @name frameIndex
     * @method
     * @memberof Konva.Sprite.prototype
     * @param {Integer} frameIndex
     * @returns {Integer}
     * @example
     * // get animation frame index
     * var frameIndex = sprite.frameIndex();
     *
     * // set animation frame index
     * sprite.frameIndex(3);
     */

    Konva.Factory.addGetterSetter(Konva.Sprite, 'frameRate', 17);

    /**
     * get/set frame rate in frames per second.  Increase this number to make the sprite
     *  animation run faster, and decrease the number to make the sprite animation run slower
     *  The default is 17 frames per second
     * @name frameRate
     * @method
     * @memberof Konva.Sprite.prototype
     * @param {Integer} frameRate
     * @returns {Integer}
     * @example
     * // get frame rate
     * var frameRate = sprite.frameRate();
     *
     * // set frame rate to 2 frames per second
     * sprite.frameRate(2);
     */

    Konva.Factory.backCompat(Konva.Sprite, {
        index: 'frameIndex',
        getIndex: 'getFrameIndex',
        setIndex: 'setFrameIndex'
    });

    Konva.Collection.mapMethods(Konva.Sprite);
})();