(function() {
    'use strict';
    // CONSTANTS
    var IMAGE = 'Image';

    /**
     * Image constructor
     * @constructor
     * @memberof Konva
     * @augments Konva.Shape
     * @param {Object} config
     * @param {Image} config.image
     * @param {Object} [config.crop]
     * @@shapeParams
     * @@nodeParams
     * @example
     * var imageObj = new Image();
     * imageObj.onload = function() {
     *   var image = new Konva.Image({
     *     x: 200,
     *     y: 50,
     *     image: imageObj,
     *     width: 100,
     *     height: 100
     *   });
     * };
     * imageObj.src = '/path/to/image.jpg'
     */
    Konva.Image = function(config) {
        this.___init(config);
    };

    Konva.Image.prototype = {
        ___init: function(config) {
            // call super constructor
            Konva.Shape.call(this, config);
            this.className = IMAGE;
            this.sceneFunc(this._sceneFunc);
            this.hitFunc(this._hitFunc);
        },
        _useBufferCanvas: function() {
            return (this.hasShadow() || this.getAbsoluteOpacity() !== 1) && this.hasStroke() && this.getStage();
        },
        _sceneFunc: function(context) {
            var width = this.getWidth(),
                height = this.getHeight(),
                image = this.getImage(),
                cropWidth, cropHeight, params;

            if (image) {
                cropWidth = this.getCropWidth();
                cropHeight = this.getCropHeight();
                if (cropWidth && cropHeight) {
                    params = [image, this.getCropX(), this.getCropY(), cropWidth, cropHeight, 0, 0, width, height];
                } else {
                    params = [image, 0, 0, width, height];
                }
            }

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

            if (image) {
                context.drawImage.apply(context, params);
            }
        },
        _hitFunc: function(context) {
            var width = this.getWidth(),
                height = this.getHeight();

            context.beginPath();
            context.rect(0, 0, width, height);
            context.closePath();
            context.fillStrokeShape(this);
        },
        getWidth: function() {
            var image = this.getImage();
            return this.attrs.width || (image ? image.width : 0);
        },
        getHeight: function() {
            var image = this.getImage();
            return this.attrs.height || (image ? image.height : 0);
        }
    };
    Konva.Util.extend(Konva.Image, Konva.Shape);

    // add getters setters
    Konva.Factory.addGetterSetter(Konva.Image, 'image');

    /**
     * set image
     * @name setImage
     * @method
     * @memberof Konva.Image.prototype
     * @param {Image} image
     */

    /**
     * get image
     * @name getImage
     * @method
     * @memberof Konva.Image.prototype
     * @returns {Image}
     */

    Konva.Factory.addComponentsGetterSetter(Konva.Image, 'crop', ['x', 'y', 'width', 'height']);
    /**
     * get/set crop
     * @method
     * @name crop
     * @memberof Konva.Image.prototype
     * @param {Object} crop
     * @param {Number} crop.x
     * @param {Number} crop.y
     * @param {Number} crop.width
     * @param {Number} crop.height
     * @returns {Object}
     * @example
     * // get crop
     * var crop = image.crop();
     *
     * // set crop
     * image.crop({
     *   x: 20,
     *   y: 20,
     *   width: 20,
     *   height: 20
     * });
     */

    Konva.Factory.addGetterSetter(Konva.Image, 'cropX', 0);
    /**
     * get/set crop x
     * @method
     * @name cropX
     * @memberof Konva.Image.prototype
     * @param {Number} x
     * @returns {Number}
     * @example
     * // get crop x
     * var cropX = image.cropX();
     *
     * // set crop x
     * image.cropX(20);
     */

    Konva.Factory.addGetterSetter(Konva.Image, 'cropY', 0);
    /**
     * get/set crop y
     * @name cropY
     * @method
     * @memberof Konva.Image.prototype
     * @param {Number} y
     * @returns {Number}
     * @example
     * // get crop y
     * var cropY = image.cropY();
     *
     * // set crop y
     * image.cropY(20);
     */

    Konva.Factory.addGetterSetter(Konva.Image, 'cropWidth', 0);
    /**
     * get/set crop width
     * @name cropWidth
     * @method
     * @memberof Konva.Image.prototype
     * @param {Number} width
     * @returns {Number}
     * @example
     * // get crop width
     * var cropWidth = image.cropWidth();
     *
     * // set crop width
     * image.cropWidth(20);
     */

    Konva.Factory.addGetterSetter(Konva.Image, 'cropHeight', 0);
    /**
     * get/set crop height
     * @name cropHeight
     * @method
     * @memberof Konva.Image.prototype
     * @param {Number} height
     * @returns {Number}
     * @example
     * // get crop height
     * var cropHeight = image.cropHeight();
     *
     * // set crop height
     * image.cropHeight(20);
     */

    Konva.Collection.mapMethods(Konva.Image);

    /**
     * load image from given url and create `Konva.Image` instance
     * @method
     * @memberof Konva.Image
     * @param {String} url image source
     * @param {Function} callback with Konva.Image instance as first argument
     * @example
     *  Konva.Image.fromURL(imageURL, function(image){
     *    // image is Konva.Image instance
     *    layer.add(image);
     *    layer.draw();
     *  });
     */
    Konva.Image.fromURL = function(url, callback) {
        var img = new Image();
        img.onload = function() {
          var image = new Konva.Image({
            image: img
          });
          callback(image);
        };
        img.src = url;
    };
})();