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/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (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.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Jetpack.
*
* The Initial Developer of the Original Code is
* the Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2010
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Irakli Gozalishvili <gozala@mozilla.com> (Original Author)
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
"use strict";
const { Cc, Ci, Cu } = require("chrome");
const AppShellService = Cc["@mozilla.org/appshell/appShellService;1"].
getService(Ci.nsIAppShellService);
const NS = "http://www.w3.org/1999/xhtml";
const COLOR = "rgb(255,255,255)";
/**
* Creates canvas element with a thumbnail of the passed window.
* @param {Window} window
* @returns {Element}
*/
function getThumbnailCanvasForWindow(window) {
let aspectRatio = 0.5625; // 16:9
let thumbnail = AppShellService.hiddenDOMWindow.document
.createElementNS(NS, "canvas");
thumbnail.mozOpaque = true;
thumbnail.width = Math.ceil(window.screen.availWidth / 5.75);
thumbnail.height = Math.round(thumbnail.width * aspectRatio);
let ctx = thumbnail.getContext("2d");
let snippetWidth = window.innerWidth * .6;
let scale = thumbnail.width / snippetWidth;
ctx.scale(scale, scale);
ctx.drawWindow(window, window.scrollX, window.scrollY, snippetWidth,
snippetWidth * aspectRatio, COLOR);
return thumbnail;
}
exports.getThumbnailCanvasForWindow = getThumbnailCanvasForWindow;
/**
* Creates Base64 encoded data URI of the thumbnail for the passed window.
* @param {Window} window
* @returns {String}
*/
exports.getThumbnailURIForWindow = function getThumbnailURIForWindow(window) {
return getThumbnailCanvasForWindow(window).toDataURL()
};
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