Add lib/screenshot.js

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

// Based on:

// http://hg.mozilla.org/qa/mozmill-tests/file/905bc0ba7a1e/firefox/lib/screenshot.js

Cu.import("resource://gre/modules/Services.jsm");

// Include the required modules

var utils = require("utils");

/**

 * This function creates a screenshot of the window provided in the given

 * controller and highlights elements from the coordinates provided in the

 * given boxes-array.

 *

 * @param {array of array of int} boxes

 * @param {MozmillController} controller

 */

function create(controller, boxes) {

  var doc = controller.window.document;

  var maxWidth = doc.documentElement.boxObject.width;

  var maxHeight = doc.documentElement.boxObject.height;

  var rect = [];

  for (var i = 0, j = boxes.length; i < j; ++i) {

    rect = boxes[i];

    if (rect[0] + rect[2] > maxWidth) maxWidth = rect[0] + rect[2];

    if (rect[1] + rect[3] > maxHeight) maxHeight = rect[1] + rect[3];

  }

  var canvas = doc.createElementNS("http://www.w3.org/1999/xhtml", "canvas");

  var width = doc.documentElement.boxObject.width;

  var height = doc.documentElement.boxObject.height;

  canvas.width = maxWidth;

  canvas.height = maxHeight;

  var ctx = canvas.getContext("2d");

  ctx.clearRect(0,0, canvas.width, canvas.height);

  ctx.save();

  ctx.drawWindow(controller.window, 0, 0, width, height, "rgb(0,0,0)");

  ctx.restore();

  ctx.save();

  ctx.fillStyle = "rgba(255,0,0,0.4)";

  for (var i = 0, j = boxes.length; i < j; ++i) {

    rect = boxes[i];

    ctx.fillRect(rect[0], rect[1], rect[2], rect[3]);

  }

  ctx.restore();

  _saveCanvas(canvas);

}

/**

 * Saves a given Canvas object to a file.

 * The path to save the file under should be given on the command line. If not,

 * it will be saved in the temporary folder of the system.

 *

 * @param {canvas} canvas

 */

function _saveCanvas(canvas) {

  // Use the path given on the command line and saved under

  // persisted.screenshotPath, if available. If not, use the path to the

  // temporary folder as a fallback.

  var file = null;

  if ("screenshotPath" in persisted) {

    file = Cc["@mozilla.org/file/local;1"].createInstance(Ci.nsILocalFile);

    file.initWithPath(persisted.screenshotPath);

  }

  else {

    file = Services.dirsvc.get("TmpD", Ci.nsIFile);

  }

  var fileName = utils.appInfo.name + "-" +

                 utils.appInfo.locale + "." +

                 utils.appInfo.version + "." +

                 utils.appInfo.buildID + "." +

                 utils.appInfo.os + ".png";

  file.append(fileName);

  // if a file already exists, don't overwrite it and create a new name

  file.createUnique(Ci.nsIFile.NORMAL_FILE_TYPE, parseInt("0666", 8));

  // create a data url from the canvas and then create URIs of the source

  // and targets

  var source = Services.io.newURI(canvas.toDataURL("image/png", ""), "UTF8", null);

  var target = Services.io.newFileURI(file)

  // prepare to save the canvas data

  var wbPersist = Cc["@mozilla.org/embedding/browser/nsWebBrowserPersist;1"].

                  createInstance(Ci.nsIWebBrowserPersist);

  wbPersist.persistFlags = Ci.nsIWebBrowserPersist.PERSIST_FLAGS_REPLACE_EXISTING_FILES;

  wbPersist.persistFlags |= Ci.nsIWebBrowserPersist.PERSIST_FLAGS_AUTODETECT_APPLY_CONVERSION;

  // save the canvas data to the file

  wbPersist.saveURI(source, null, null, null, null, file, null);

}

// Export of functions

exports.create = create;