/* 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/. */

"use strict";

ChromeUtils.import("resource://gre/modules/XPCOMUtils.jsm");
ChromeUtils.import("resource://gre/modules/Services.jsm");
ChromeUtils.defineModuleGetter(this, "PlacesUtils",
                               "resource://gre/modules/PlacesUtils.jsm");
ChromeUtils.defineModuleGetter(this, "NetUtil",
                               "resource://gre/modules/NetUtil.jsm");

function makeDefaultFaviconChannel(uri, loadInfo) {
  let channel = Services.io.newChannelFromURIWithLoadInfo(
    PlacesUtils.favicons.defaultFavicon, loadInfo);
  channel.originalURI = uri;
  channel.contentType = PlacesUtils.favicons.defaultFaviconMimeType;
  return channel;
}

function streamDefaultFavicon(uri, loadInfo, outputStream, originalChannel) {
  try {
    // Open up a new channel to get that data, and push it to our output stream.
    // Create a listener to hand data to the pipe's output stream.
    let listener = Cc["@mozilla.org/network/simple-stream-listener;1"]
                     .createInstance(Ci.nsISimpleStreamListener);
    listener.init(outputStream, {
      onStartRequest(request, context) {},
      onStopRequest(request, context, statusCode) {
        // We must close the outputStream regardless.
        outputStream.close();
      },
    });
    originalChannel.contentType = PlacesUtils.favicons.defaultFaviconMimeType;
    let defaultIconChannel = makeDefaultFaviconChannel(uri, loadInfo);
    defaultIconChannel.asyncOpen2(listener);
  } catch (ex) {
    Cu.reportError(ex);
    outputStream.close();
  }
}

function serveIcon(pipe, data, len) {
  // Pass the icon data to the output stream.
  let stream = Cc["@mozilla.org/binaryoutputstream;1"]
                 .createInstance(Ci.nsIBinaryOutputStream);
  stream.setOutputStream(pipe.outputStream);
  stream.writeByteArray(data, len);
  stream.close();
  pipe.outputStream.close();
}

function PageIconProtocolHandler() {
}

PageIconProtocolHandler.prototype = {
  get scheme() {
    return "page-icon";
  },

  get defaultPort() {
    return -1;
  },

  get protocolFlags() {
    return Ci.nsIProtocolHandler.URI_NORELATIVE |
           Ci.nsIProtocolHandler.URI_NOAUTH |
           Ci.nsIProtocolHandler.URI_DANGEROUS_TO_LOAD |
           Ci.nsIProtocolHandler.URI_IS_LOCAL_RESOURCE;
  },

  newURI(spec, originCharset, baseURI) {
    return Cc["@mozilla.org/network/simple-uri-mutator;1"]
             .createInstance(Ci.nsIURIMutator)
             .setSpec(spec)
             .finalize();
  },

  newChannel2(uri, loadInfo) {
    try {
      // Create a pipe that will give us an output stream that we can use once
      // we got all the favicon data.
      let pipe = Cc["@mozilla.org/pipe;1"]
                   .createInstance(Ci.nsIPipe);
      pipe.init(true, true, 0, Ci.nsIFaviconService.MAX_FAVICON_BUFFER_SIZE);

      // Create our channel.
      let channel = Cc["@mozilla.org/network/input-stream-channel;1"]
                      .createInstance(Ci.nsIInputStreamChannel);
      channel.QueryInterface(Ci.nsIChannel);
      channel.setURI(uri);
      channel.contentStream = pipe.inputStream;
      channel.loadInfo = loadInfo;

      let pageURI = NetUtil.newURI(uri.pathQueryRef.replace(/[&#]size=[^&]+$/, ""));
      let preferredSize = PlacesUtils.favicons.preferredSizeFromURI(uri);
      PlacesUtils.favicons.getFaviconDataForPage(pageURI, (iconURI, len, data, mimeType) => {
        if (len == 0) {
          streamDefaultFavicon(uri, loadInfo, pipe.outputStream, channel);
        } else {
          try {
            channel.contentType = mimeType;
            channel.contentLength = len;
            serveIcon(pipe, data, len);
          } catch (ex) {
            streamDefaultFavicon(uri, loadInfo, pipe.outputStream, channel);
          }
        }
      }, preferredSize);

      return channel;
    } catch (ex) {
      return makeDefaultFaviconChannel(uri, loadInfo);
    }
  },

  newChannel(uri) {
    return this.newChannel2(uri, null);
  },

  allowPort(port, scheme) {
    return false;
  },

  classID: Components.ID("{60a1f7c6-4ff9-4a42-84d3-5a185faa6f32}"),
  QueryInterface: ChromeUtils.generateQI([
    Ci.nsIProtocolHandler,
    Ci.nsISupportsWeakReference,
  ]),
};

this.NSGetFactory = XPCOMUtils.generateNSGetFactory([PageIconProtocolHandler]);