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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 Places code.
 *
 * The Initial Developer of the Original Code is the Mozilla Foundation.
 *
 * Portions created by the Initial Developer are Copyright (C) 2011
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Justin Lebar <justin.lebar@gmail.com>
 *
 * 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
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#include "nsISupports.idl"

interface nsIURI;
interface nsIFaviconDataCallback;

/**
 * Interface for accessing the favicon service asynchronously.
 *
 * @status EXPERIMENTAL
 */

[scriptable, uuid(f3530e8d-0016-4f56-91fe-28958a7ec296)]
interface mozIAsyncFavicons : nsISupports
{
  /**
   * Declares that a given page uses a favicon with the given URI and 
   * attempts to fetch and save the icon data by loading the favicon URI
   * through an async network request.
   *
   * If the icon data already exists, we won't try to reload the icon unless
   * aForceReload is true.  Similarly, if the icon is in the failed favicon
   * cache we won't do anything unless aForceReload is true, in which case
   * we'll try to reload the favicon.
   *
   * This function will only save favicons for "good" URIs, as defined by what
   * gets added to history or is a bookmark.  For "bad" URIs, this function
   * will succeed but do nothing.  This function will also ignore the error
   * page favicon URI (see FAVICON_ERRORPAGE_URL below).
   *
   * Icons that fail to load will automatically be added to the failed favicon
   * cache, and this function will not save favicons for non-bookmarked URIs
   * when history is disabled.
   *
   * @note This function is identical to
   *       nsIFaviconService::setAndLoadFaviconForPage.
   *
   * @param aPageURI
   *        URI of the page whose favicon is being set.
   * @param aFaviconURI
   *        URI of the favicon to associate with the page.
   * @param aForceReload
   *        If aForceReload is false, we try to reload the favicon only if we
   *        don't have it or it has expired from the cache.  Setting
   *        aForceReload to true causes us to reload the favicon even if we
   *        have a usable copy.
   * @param aCallback
   *        Once we're done setting and/or fetching the favicon, we invoke this
   *        callback.
   *
   * @see nsIFaviconDataCallback in nsIFaviconService.idl.
   */
  void setAndFetchFaviconForPage(in nsIURI aPageURI,
                                 in nsIURI aFaviconURI,
                                 in boolean aForceReload,
                                 [optional] in nsIFaviconDataCallback aCallback);

  /**
   * Sets the data for a given favicon URI either by replacing existing data in
   * the database or taking the place of otherwise fetched icon data when
   * calling setAndFetchFaviconForPage later.
   *
   * Favicon data for favicon URIs that are not associated with a page URI via
   * setAndFetchFaviconForPage will be stored in memory, but may be expired at
   * any time, so you should make an effort to associate favicon URIs with page
   * URIs as soon as possible.
   *
   * It's better to not use this function for chrome: icon URIs since you can
   * reference the chrome image yourself. getFaviconLinkForIcon/Page will ignore
   * any associated data if the favicon URI is "chrome:" and just return the
   * same chrome URI.
   *
   * This function does NOT send out notifications that the data has changed.
   * Pages using this favicons that are visible in history or bookmarks views
   * will keep the old icon until they have been refreshed by other means.
   *
   * This function tries to optimize the favicon size, if it is bigger
   * than a defined limit we will try to convert it to a 16x16 png image.
   * If the conversion fails and favicon is still bigger than our max accepted
   * size it won't be saved.
   *
   * @param aFaviconURI
   *        URI of the favicon whose data is being set.
   * @param aData
   *        Binary contents of the favicon to save
   * @param aDataLength
   *        Length of binary data
   * @param aMimeType
   *        MIME type of the data to store.  This is important so that we know
   *        what to report when the favicon is used.  You should always set this
   *        param unless you are clearing an icon.
   * @param aExpiration
   *        Time in microseconds since the epoch when this favicon expires.
   *        Until this time, we won't try to load it again.
   * @throws NS_ERROR_FAILURE
   *         Thrown if the favicon is overbloated and won't be saved to the db.
   */
  void replaceFaviconData(in nsIURI aFaviconURI,
                          [const,array,size_is(aDataLen)] in octet aData,
                          in unsigned long aDataLen,
                          in AUTF8String aMimeType,
                          [optional] in PRTime aExpiration);

  /**
   * Same as replaceFaviconData but the data is provided by a string
   * containing a data URL.
   *
   * @see replaceFaviconData
   *
   * @param aFaviconURI
   *        URI of the favicon whose data is being set.
   * @param aDataURL
   *        string containing a data URL that represents the contents of
   *        the favicon to save
   * @param aExpiration
   *        Time in microseconds since the epoch when this favicon expires.
   *        Until this time, we won't try to load it again.
   * @throws NS_ERROR_FAILURE
   *         Thrown if the favicon is overbloated and won't be saved to the db.
   */
  void replaceFaviconDataFromDataURL(in nsIURI aFaviconURI,
                                     in AString aDataURL,
                                     [optional] in PRTime aExpiration);

  /**
   * Retrieve the URL of the favicon for the given page.
   *
   * @param aPageURI
   *        URI of the page whose favicon's URL we're looking up
   * @param aCallback
   *        Once we've found the favicon's URL, we invoke this callback.  Note
   *        that the callback's aDataLen will be 0, aData will be null, and
   *        aMimeType will be empty -- only aURI will be non-zero/null/empty.
   *
   * @see nsIFaviconDataCallback in nsIFaviconService.idl.
   */
  void getFaviconURLForPage(in nsIURI aPageURI,
                            in nsIFaviconDataCallback aCallback);

  /**
   * Retrieve the URL and data of the favicon for the given page.
   *
   * @param aPageURI
   *        URI of the page whose favicon's URL and data we're looking up
   * @param aCallback
   *        Once we've found the favicon's URL, we invoke this callback with
   *        the favicon data.
   *
   * @see nsIFaviconDataCallback in nsIFaviconService.idl.
   */
  void getFaviconDataForPage(in nsIURI aPageURI,
                             in nsIFaviconDataCallback aCallback);
};
