;
(function (document) {

    /*****************
     * Canva Object
     *****************/
    var Canva = function (domCanva) {
        this.domCanva = domCanva;
    };

    Canva.prototype = {
        resize: function (elementDomNode) {
            var w = elementDomNode.getWidth();
            var maxH = elementDomNode.getHeight();

            if ('' !== elementDomNode.getAspectRatio()) {
                var ratio = parseFloat(elementDomNode.getAspectRatio());

                var h = Math.round(w * (1 / ratio));

                if (h > maxH) {
                    var h = maxH;
                    var w = Math.round(h * ratio);
                }
            } else {
                var h = maxH;
            }

            this.domCanva.setAttribute("width", w);
            this.domCanva.setAttribute("height", h);

            return this;
        },
        getContext2d: function () {

            if (undefined === this.domCanva.getContext) {
                return G_vmlCanvasManager
                    .initElement(this.domCanva)
                    .getContext("2d");
            }

            return this.domCanva.getContext('2d');
        },
        extractImage: function () {
            return this.domCanva.toDataURL("image/png");
        },
        reset: function () {
            var context = this.getContext2d();
            var w = this.getWidth();
            var h = this.getHeight();

            context.save();
            context.setTransform(1, 0, 0, 1, 0, 0);
            context.clearRect(0, 0, w, h);
            context.restore();

            return this;
        },
        copy: function (elementDomNode) {
            var context = this.getContext2d();

            context.drawImage(
                elementDomNode.getDomElement()
                , 0
                , 0
                , this.getWidth()
                , this.getHeight()
            );

            return this;
        },
        getDomElement: function () {
            return this.domCanva;
        },
        getHeight: function () {
            return this.domCanva.offsetHeight;
        },
        getWidth: function () {
            return this.domCanva.offsetWidth;
        }
    };


    /******************
     *  Image Object
     ******************/
    var Image = function (domElement) {
        this.domElement = domElement;
    };

    Image.prototype = {
        getDomElement: function () {
            return this.domElement;
        },
        getHeight: function () {
            return this.domElement.offsetHeight;
        },
        getWidth: function () {
            return this.domElement.offsetWidth;
        }
    };

    /******************
     *  Video Object inherits from Image object
     ******************/

    var Video = function (domElement) {
        Image.call(this, domElement);
        this.aspectRatio = domElement.getAttribute('data-ratio');
    };

    Video.prototype = new Image();
    Video.prototype.constructor = Video;
    Video.prototype.getCurrentTime = function () {
        return Math.floor(this.domElement.currentTime);
    };
    Video.prototype.getAspectRatio = function () {
        return this.aspectRatio;
    };

    /******************
     *  Cache Object
     ******************/
    var Store = function () {
        this.datas = {};
    };

    Store.prototype = {
        set: function (id, item) {
            this.datas[id] = item;
            return this;
        },
        get: function (id) {
            if (!this.datas[id]) {
                throw 'Unknown ID';
            }
            return this.datas[id];
        },
        remove: function (id) {
            delete this.datas[id];
        },
        getLength: function () {
            var count = 0;
            for (var k in this.datas) {
                if (this.datas.hasOwnProperty(k)) {
                    ++count;
                }
            }
            return count;
        }
    };

    /******************
     *  Screenshot Object
     ******************/
    var ScreenShot = function (id, canva, video) {

        var date = new Date();

        canva.resize(video);
        canva.copy(video);

        this.id = id;
        this.timestamp = date.getTime();
        this.dataURI = canva.extractImage();
        this.videoTime = video.getCurrentTime();
    };

    ScreenShot.prototype = {
        getId: function () {
            return this.id;
        },
        getDataURI: function () {
            return this.dataURI;
        },
        getTimeStamp: function () {
            return this.timestamp;
        },
        getVideoTime: function () {
            return this.videoTime;
        }
    };

    /**
     * THUMB EDITOR
     */
    var ThumbEditor = function (videoId, canvaId) {

        var domElement = document.getElementById(videoId);

        if (null !== domElement) {
            var editorVideo = new Video(domElement);
        }
        var store = new Store();

        function getCanva() {
            return document.getElementById(canvaId);
        }

        return {
            isSupported: function () {
                var elem = document.createElement('canvas');

                return !!document.getElementById(videoId) && document.getElementById(canvaId)
                    && !!elem.getContext && !!elem.getContext('2d');
            },
            screenshot: function () {
                var screenshot = new ScreenShot(
                    store.getLength() + 1,
                    new Canva(getCanva()),
                    editorVideo
                );

                store.set(screenshot.getId(), screenshot);

                return screenshot;
            },
            store: store,
            copy: function (elementDomNode) {
                var element = new Image(elementDomNode);
                var editorCanva = new Canva(getCanva());
                editorCanva
                    .reset()
                    .resize(editorVideo)
                    .copy(element);
            },
            getCanvaImage: function () {
                var canva = new Canva(getCanva());
                return canva.extractImage();
            },
            resetCanva: function () {
                var editorCanva = new Canva(getCanva());
                editorCanva.reset();
            },
            getNbScreenshot: function () {
                return store.getLength();
            }
        };
    };

    document.THUMB_EDITOR = ThumbEditor;

})(document);