extensions/renderer/resources/set_icon.js

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 var SetIconCommon = requireNative('setIcon').SetIconCommon;
   6 var sendRequest = require('sendRequest').sendRequest;
   7
   8 function loadImagePath(path, iconSize, callback) {
   9   var img = new Image();
  10   img.onerror = function() {
  11     console.error('Could not load action icon \'' + path + '\'.');
  12   };
  13   img.onload = function() {
  14     var canvas = document.createElement('canvas');
  15     canvas.width = img.width > iconSize ? iconSize : img.width;
  16     canvas.height = img.height > iconSize ? iconSize : img.height;
  17
  18     var canvas_context = canvas.getContext('2d');
  19     canvas_context.clearRect(0, 0, canvas.width, canvas.height);
  20     canvas_context.drawImage(img, 0, 0, canvas.width, canvas.height);
  21     var imageData = canvas_context.getImageData(0, 0, canvas.width,
  22                                                 canvas.height);
  23     callback(imageData);
  24   };
  25   img.src = path;
  26 }
  27
  28 function verifyImageData(imageData, iconSize) {
  29   // Verify that this at least looks like an ImageData element.
  30   // Unfortunately, we cannot use instanceof because the ImageData
  31   // constructor is not public.
  32   //
  33   // We do this manually instead of using JSONSchema to avoid having these
  34   // properties show up in the doc.
  35   if (!('width' in imageData) ||
  36       !('height' in imageData) ||
  37       !('data' in imageData)) {
  38     throw new Error(
  39         'The imageData property must contain an ImageData object or' +
  40         ' dictionary of ImageData objects.');
  41   }
  42
  43   if (imageData.width > iconSize ||
  44       imageData.height > iconSize) {
  45     throw new Error(
  46         'The imageData property must contain an ImageData object that ' +
  47         'is no larger than ' + iconSize + ' pixels square.');
  48   }
  49 }
  50
  51 /**
  52  * Normalizes |details| to a format suitable for sending to the browser,
  53  * for example converting ImageData to a binary representation.
  54  *
  55  * @param {ImageDetails} details
  56  *   The ImageDetails passed into an extension action-style API.
  57  * @param {Function} callback
  58  *   The callback function to pass processed imageData back to. Note that this
  59  *   callback may be called reentrantly.
  60  */
  61 function setIcon(details, callback) {
  62   var iconSizes = [19, 38];
  63   // Note that iconIndex is actually deprecated, and only available to the
  64   // pageAction API.
  65   // TODO(kalman): Investigate whether this is for the pageActions API, and if
  66   // so, delete it.
  67   if ('iconIndex' in details) {
  68     callback(details);
  69     return;
  70   }
  71
  72   if ('imageData' in details) {
  73     var isEmpty = true;
  74     for (var i = 0; i < iconSizes.length; i++) {
  75       var sizeKey = iconSizes[i].toString();
  76       if (sizeKey in details.imageData) {
  77         verifyImageData(details.imageData[sizeKey], iconSizes[i]);
  78         isEmpty =false;
  79       }
  80     }
  81
  82     if (isEmpty) {
  83       // If details.imageData is not dictionary with keys in set {'19', '38'},
  84       // it must be an ImageData object.
  85       var sizeKey = iconSizes[0].toString();
  86       var imageData = details.imageData;
  87       details.imageData = {};
  88       details.imageData[sizeKey] = imageData;
  89       verifyImageData(details.imageData[sizeKey], iconSizes[0]);
  90     }
  91     callback(SetIconCommon(details));
  92     return;
  93   }
  94
  95   if ('path' in details) {
  96     if (typeof details.path == 'object') {
  97       details.imageData = {};
  98       var isEmpty = true;
  99       var processIconSize = function(index) {
 100         if (index == iconSizes.length) {
 101           delete details.path;
 102           if (isEmpty)
 103             throw new Error('The path property must not be empty.');
 104           callback(SetIconCommon(details));
 105           return;
 106         }
 107         var sizeKey = iconSizes[index].toString();
 108         if (!(sizeKey in details.path)) {
 109           processIconSize(index + 1);
 110           return;
 111         }
 112         isEmpty = false;
 113         loadImagePath(details.path[sizeKey], iconSizes[index],
 114           function(imageData) {
 115             details.imageData[sizeKey] = imageData;
 116             processIconSize(index + 1);
 117           });
 118       }
 119       processIconSize(0);
 120     } else if (typeof details.path == 'string') {
 121       var sizeKey = iconSizes[0].toString();
 122       details.imageData = {};
 123       loadImagePath(details.path, iconSizes[0],
 124           function(imageData) {
 125             details.imageData[sizeKey] = imageData;
 126             delete details.path;
 127             callback(SetIconCommon(details));
 128             return;
 129       });
 130     }
 131     return;
 132   }
 133   throw new Error('Either the path or imageData property must be specified.');
 134 }
 135
 136 exports.setIcon = setIcon;