"use strict";

/*
Copyright [2014] [Diagramo]

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

/**
 * Used to do/undo actions when the canvas gets fitted.
 * Function will translate everything on canvas on (-startX, -startY).
 * @this {CanvasFitCommand}
 * @constructor
 * @param {Number} newWidth - the new width of the canvas
 * @param {Number} newHeight - the new height of the canvas
 * @param {Number} startX - the new X coordinate to shift start point
 * @param {Number} startY - the new Y coordinate to shift start point
 * @author Arty
 */
function CanvasFitCommand(newWidth, newHeight, startX, startY){

    this.previousWidth = canvasProps.width;
    this.previousHeight = canvasProps.height;

    this.width = newWidth;
    this.height = newHeight;

    this.startX = typeof(startX) !== 'undefined' ? startX : 0;
    this.startY = typeof(startY) !== 'undefined' ? startY : 0;

    // define if canvas should change size or become translated
    this.canvasResizing = this.previousWidth !== this.width || this.previousHeight !== this.height;
    this.canvasTranslation = this.startX !== 0 || this.startY !== 0;

    this.oType = "CanvasFitCommand";
}

CanvasFitCommand.prototype = {

    constructor : CanvasFitCommand,

    /**This method got called every time the Command must execute*/
    execute : function(){
        // Does canvas should be translated?
        if (this.canvasTranslation) {
            // get translation matrix
            var translationMatrix = Matrix.translationMatrix(-this.startX, -this.startY);
            // apply translation to objects in STACK
            STACK.transform(translationMatrix);
        }

        // Does canvas should be resized?
        if (this.canvasResizing) {
            // set new size of canvas
            canvasProps.setWidth(this.width);
            canvasProps.setHeight(this.height);
        }

        setUpEditPanel(canvasProps);
    },


    /**This method should be called every time the Command should be undone*/
    undo : function(){
        // Canvas was resized?
        if (this.canvasResizing) {
            // set previous size of canvas
            canvasProps.setWidth(this.previousWidth);
            canvasProps.setHeight(this.previousHeight);
        }

        // Canvas was translated?
        if (this.canvasTranslation) {
            // get backward translation matrix
            var translationMatrix = Matrix.translationMatrix(this.startX, this.startY);
            // apply translation to objects in STACK
            STACK.transform(translationMatrix);
        }

        setUpEditPanel(canvasProps);
    }
};