/* global extendPrototype, BaseElement, TransformElement, CVBaseElement,HierarchyElement, FrameElement,
RenderableElement, SVGShapeElement, IImageElement, createTag */

function CVImageElement(data, globalData, comp) {
  this.assetData = globalData.getAssetData(data.refId);
  this.img = globalData.imageLoader.getAsset(this.assetData);
  this.initElement(data, globalData, comp);
}
extendPrototype([BaseElement, TransformElement, CVBaseElement, HierarchyElement, FrameElement, RenderableElement], CVImageElement);

CVImageElement.prototype.initElement = SVGShapeElement.prototype.initElement;
CVImageElement.prototype.prepareFrame = IImageElement.prototype.prepareFrame;

CVImageElement.prototype.createContent = function () {
  if (this.img.width && (this.assetData.w !== this.img.width || this.assetData.h !== this.img.height)) {
    var canvas = createTag('canvas');
    canvas.width = this.assetData.w;
    canvas.height = this.assetData.h;
    var ctx = canvas.getContext('2d');

    var imgW = this.img.width;
    var imgH = this.img.height;
    var imgRel = imgW / imgH;
    var canvasRel = this.assetData.w / this.assetData.h;
    var widthCrop;
    var heightCrop;
    var par = this.assetData.pr || this.globalData.renderConfig.imagePreserveAspectRatio;
    if ((imgRel > canvasRel && par === 'xMidYMid slice') || (imgRel < canvasRel && par !== 'xMidYMid slice')) {
      heightCrop = imgH;
      widthCrop = heightCrop * canvasRel;
    } else {
      widthCrop = imgW;
      heightCrop = widthCrop / canvasRel;
    }
    ctx.drawImage(this.img, (imgW - widthCrop) / 2, (imgH - heightCrop) / 2, widthCrop, heightCrop, 0, 0, this.assetData.w, this.assetData.h);
    this.img = canvas;
  }
};

CVImageElement.prototype.renderInnerContent = function () {
  this.canvasContext.drawImage(this.img, 0, 0);
};

CVImageElement.prototype.destroy = function () {
  this.img = null;
};