etherpad-lite/static/js/timeslider.js

/**
 * This code is mostly from the old Etherpad. Please help us to comment this code.
 * This helps other people to understand this code better and helps them to improve it.
 * TL;DR COMMENTS ON THIS FILE ARE HIGHLY APPRECIATED
 */

/**
 * Copyright 2009 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS-IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// These jQuery things should create local references, but for now `require()`
// assigns to the global `$` and augments it with plugins.
require('/jquery');
JSON = require('/json2');
require('/undo-xpopup');

var createCookie  = require('/pad_utils').createCookie,
    readCookie    = require('/pad_utils').readCookie,
    randomString  = require('/pad_utils').randomString,
    socket, token, padId, export_links;

function init() {
  $(document).ready(function () {
    // start the custom js
    if (typeof customStart == 'function')
      customStart();

    // get padId from url
    var urlParts = document.location.pathname.split('/');
    padId = decodeURIComponent(urlParts[urlParts.length - 2]);

    // set the title
    document.title = padId.replace(/_+/g, ' ') + ' | ' + document.title;

    // ensure we have a token
    token = readCookie('token');
    if (token == null) {
      token = 't.' + randomString();
      createCookie('token', token, 60);
    }

    var loc       = document.location,
        port      = loc.port == '' ? (loc.protocol == 'https:' ? 443 : 80) : loc.port,  // get the correct port
        url       = loc.protocol + '//' + loc.hostname + ':' + port + '/',              // create the url
        resource  = loc.pathname.substr(1, loc.pathname.indexOf('/p/')) + 'socket.io';  // find out in which subfolder we are

    // build up the socket io connection
    socket = io.connect(url, {resource: resource});

    // send the ready message once we're connected
    socket.on('connect', function() {
      sendSocketMsg('CLIENT_READY', {});
    });

    // route the incoming messages
    socket.on('message', function(message) {
      if (window.console)
        console.log(message);
      if (message.type == 'CLIENT_VARS')
        handleClientVars(message);
      else if (message.type == 'CHANGESET_REQ')
        changesetLoader.handleSocketResponse(message);
      else if (message.accessStatus)
        $('BODY').html('<h2>You have no permission to access this pad</h2>');
    });

    // get all export links
    export_links = $('.exportlink');

    if (document.referrer.length > 0 && document.referrer.substring(document.referrer.lastIndexOf('/') - 1, document.referrer.lastIndexOf('/')) === 'p')
      $('#returnbutton A').attr('href', document.referrer);
    else
      $('#returnbutton A').attr('href', document.location.href.substring(0, document.location.href.lastIndexOf('/')));
  });
}

// send a message over the socket
function sendSocketMsg(type, data) {
  var sessionID = readCookie('sessionID'),
      password  = readCookie('password'),
      msg       = { 'component'       : 'timeslider',
                    'type'            : type,
                    'data'            : data,
                    'padId'           : padId,
                    'token'           : token,
                    'sessionID'       : sessionID,
                    'password'        : password,
                    'protocolVersion' : 2
                  };
  socket.json.send(msg);
}

var fireWhenAllScriptsAreLoaded = [],
    BroadcastSlider, changesetLoader;

function handleClientVars(message) {
  // save the client Vars
  clientVars = message.data;
  
  // load all scripts that don't work without the clientVars
  BroadcastSlider = require('/broadcast_slider').loadBroadcastSliderJS(fireWhenAllScriptsAreLoaded);
  require('/broadcast_revisions').loadBroadcastRevisionsJS();
  changesetLoader = require('/broadcast').loadBroadcastJS(socket, sendSocketMsg, fireWhenAllScriptsAreLoaded, BroadcastSlider);

  // initialize export ui
  require('/pad_impexp').padimpexp.init();

  // change export urls when the slider moves
  var export_rev_regex = /(\/\d+)?\/export/;
  BroadcastSlider.onSlider(function(revno) {
    export_links.each(function() {
      this.setAttribute('href', this.href.replace(export_rev_regex, '/' + revno + '/export'));
    });
  });

  // fire all start functions of these scripts, formerly fired with window.load
  for (var i=0, l=fireWhenAllScriptsAreLoaded.length; i < l; i++) {
    fireWhenAllScriptsAreLoaded[i]();
  }
}

exports.init = init;