electron/atom/browser/lib/guest-view-manager.js

const ipcMain = require('electron').ipcMain;
const webContents = require('electron').webContents;

var slice = [].slice;

// Doesn't exist in early initialization.
var webViewManager = null;

var supportedWebViewEvents = ['load-commit', 'did-finish-load', 'did-fail-load', 'did-frame-finish-load', 'did-start-loading', 'did-stop-loading', 'did-get-response-details', 'did-get-redirect-request', 'dom-ready', 'console-message', 'devtools-opened', 'devtools-closed', 'devtools-focused', 'new-window', 'will-navigate', 'did-navigate', 'did-navigate-in-page', 'close', 'crashed', 'gpu-crashed', 'plugin-crashed', 'destroyed', 'page-title-updated', 'page-favicon-updated', 'enter-html-full-screen', 'leave-html-full-screen', 'media-started-playing', 'media-paused', 'found-in-page', 'did-change-theme-color'];

var nextInstanceId = 0;
var guestInstances = {};
var embedderElementsMap = {};
var reverseEmbedderElementsMap = {};

// Moves the last element of array to the first one.
var moveLastToFirst = function(list) {
  return list.unshift(list.pop());
};

// Generate guestInstanceId.
var getNextInstanceId = function() {
  return ++nextInstanceId;
};

// Create a new guest instance.
var createGuest = function(embedder, params) {
  var destroy, destroyEvents, event, fn, guest, i, id, j, len, len1, listeners;
  if (webViewManager == null) {
    webViewManager = process.atomBinding('web_view_manager');
  }
  id = getNextInstanceId(embedder);
  guest = webContents.create({
    isGuest: true,
    partition: params.partition,
    embedder: embedder
  });
  guestInstances[id] = {
    guest: guest,
    embedder: embedder
  };

  // Destroy guest when the embedder is gone or navigated.
  destroyEvents = ['will-destroy', 'crashed', 'did-navigate'];
  destroy = function() {
    if (guestInstances[id] != null) {
      return destroyGuest(embedder, id);
    }
  };
  for (i = 0, len = destroyEvents.length; i < len; i++) {
    event = destroyEvents[i];
    embedder.once(event, destroy);

    // Users might also listen to the crashed event, so We must ensure the guest
    // is destroyed before users' listener gets called. It is done by moving our
    // listener to the first one in queue.
    listeners = embedder._events[event];
    if (Array.isArray(listeners)) {
      moveLastToFirst(listeners);
    }
  }
  guest.once('destroyed', function() {
    var j, len1, results;
    results = [];
    for (j = 0, len1 = destroyEvents.length; j < len1; j++) {
      event = destroyEvents[j];
      results.push(embedder.removeListener(event, destroy));
    }
    return results;
  });

  // Init guest web view after attached.
  guest.once('did-attach', function() {
    var opts;
    params = this.attachParams;
    delete this.attachParams;
    this.viewInstanceId = params.instanceId;
    this.setSize({
      normal: {
        width: params.elementWidth,
        height: params.elementHeight
      },
      enableAutoSize: params.autosize,
      min: {
        width: params.minwidth,
        height: params.minheight
      },
      max: {
        width: params.maxwidth,
        height: params.maxheight
      }
    });
    if (params.src) {
      opts = {};
      if (params.httpreferrer) {
        opts.httpReferrer = params.httpreferrer;
      }
      if (params.useragent) {
        opts.userAgent = params.useragent;
      }
      this.loadURL(params.src, opts);
    }
    if (params.allowtransparency != null) {
      this.setAllowTransparency(params.allowtransparency);
    }
    return guest.allowPopups = params.allowpopups;
  });

  // Dispatch events to embedder.
  fn = function(event) {
    return guest.on(event, function() {
      var args = 2 <= arguments.length ? slice.call(arguments, 1) : [];
      return embedder.send.apply(embedder, ["ATOM_SHELL_GUEST_VIEW_INTERNAL_DISPATCH_EVENT-" + guest.viewInstanceId, event].concat(slice.call(args)));
    });
  };
  for (j = 0, len1 = supportedWebViewEvents.length; j < len1; j++) {
    event = supportedWebViewEvents[j];
    fn(event);
  }

  // Dispatch guest's IPC messages to embedder.
  guest.on('ipc-message-host', function(_, packed) {
    var args, channel;
    channel = packed[0], args = 2 <= packed.length ? slice.call(packed, 1) : [];
    return embedder.send.apply(embedder, ["ATOM_SHELL_GUEST_VIEW_INTERNAL_IPC_MESSAGE-" + guest.viewInstanceId, channel].concat(slice.call(args)));
  });

  // Autosize.
  guest.on('size-changed', function() {
    var args = 2 <= arguments.length ? slice.call(arguments, 1) : [];
    return embedder.send.apply(embedder, ["ATOM_SHELL_GUEST_VIEW_INTERNAL_SIZE_CHANGED-" + guest.viewInstanceId].concat(slice.call(args)));
  });
  return id;
};

// Attach the guest to an element of embedder.
var attachGuest = function(embedder, elementInstanceId, guestInstanceId, params) {
  var guest, key, oldGuestInstanceId, ref1, webPreferences;
  guest = guestInstances[guestInstanceId].guest;

  // Destroy the old guest when attaching.
  key = (embedder.getId()) + "-" + elementInstanceId;
  oldGuestInstanceId = embedderElementsMap[key];
  if (oldGuestInstanceId != null) {

    // Reattachment to the same guest is not currently supported.
    if (oldGuestInstanceId === guestInstanceId) {
      return;
    }
    if (guestInstances[oldGuestInstanceId] == null) {
      return;
    }
    destroyGuest(embedder, oldGuestInstanceId);
  }
  webPreferences = {
    guestInstanceId: guestInstanceId,
    nodeIntegration: (ref1 = params.nodeintegration) != null ? ref1 : false,
    plugins: params.plugins,
    webSecurity: !params.disablewebsecurity,
    blinkFeatures: params.blinkfeatures
  };
  if (params.preload) {
    webPreferences.preloadURL = params.preload;
  }
  webViewManager.addGuest(guestInstanceId, elementInstanceId, embedder, guest, webPreferences);
  guest.attachParams = params;
  embedderElementsMap[key] = guestInstanceId;
  return reverseEmbedderElementsMap[guestInstanceId] = key;
};

// Destroy an existing guest instance.
var destroyGuest = function(embedder, id) {
  var key;
  webViewManager.removeGuest(embedder, id);
  guestInstances[id].guest.destroy();
  delete guestInstances[id];
  key = reverseEmbedderElementsMap[id];
  if (key != null) {
    delete reverseEmbedderElementsMap[id];
    return delete embedderElementsMap[key];
  }
};

ipcMain.on('ATOM_SHELL_GUEST_VIEW_MANAGER_CREATE_GUEST', function(event, params, requestId) {
  return event.sender.send("ATOM_SHELL_RESPONSE_" + requestId, createGuest(event.sender, params));
});

ipcMain.on('ATOM_SHELL_GUEST_VIEW_MANAGER_ATTACH_GUEST', function(event, elementInstanceId, guestInstanceId, params) {
  return attachGuest(event.sender, elementInstanceId, guestInstanceId, params);
});

ipcMain.on('ATOM_SHELL_GUEST_VIEW_MANAGER_DESTROY_GUEST', function(event, id) {
  return destroyGuest(event.sender, id);
});

ipcMain.on('ATOM_SHELL_GUEST_VIEW_MANAGER_SET_SIZE', function(event, id, params) {
  var ref1;
  return (ref1 = guestInstances[id]) != null ? ref1.guest.setSize(params) : void 0;
});

ipcMain.on('ATOM_SHELL_GUEST_VIEW_MANAGER_SET_ALLOW_TRANSPARENCY', function(event, id, allowtransparency) {
  var ref1;
  return (ref1 = guestInstances[id]) != null ? ref1.guest.setAllowTransparency(allowtransparency) : void 0;
});

// Returns WebContents from its guest id.
exports.getGuest = function(id) {
  var ref1;
  return (ref1 = guestInstances[id]) != null ? ref1.guest : void 0;
};

// Returns the embedder of the guest.
exports.getEmbedder = function(id) {
  var ref1;
  return (ref1 = guestInstances[id]) != null ? ref1.embedder : void 0;
};