client_plugin_host_desktop_impl.js

// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

/**
 * @fileoverview
 * Provides an interface to manage the Host Desktop of a remoting session.
 */

var remoting = remoting || {};
remoting.ClientPlugin = remoting.ClientPlugin || {};

(function() {

'use strict';

/**
 * @param {remoting.ClientPluginImpl} plugin
 * @param {function(Object):void} postMessageCallback Callback to post a message
 *   to the Client Plugin.
 *
 * @implements {remoting.HostDesktop}
 * @extends {base.EventSourceImpl}
 * @constructor
 */
remoting.ClientPlugin.HostDesktopImpl = function(plugin, postMessageCallback) {
  /** @private */
  this.plugin_ = plugin;
  /** @private */
  this.width_ = 0;
  /** @private */
  this.height_ = 0;
  /** @private */
  this.xDpi_ = 96;
  /** @private */
  this.yDpi_ = 96;
  /** @private */
  this.postMessageCallback_ = postMessageCallback;

  this.defineEvents(base.values(remoting.HostDesktop.Events));
};
base.extend(remoting.ClientPlugin.HostDesktopImpl, base.EventSourceImpl);

/** @return {boolean} Whether the host supports desktop resizing. */
remoting.ClientPlugin.HostDesktopImpl.prototype.isResizable = function() {
  return this.plugin_.hasFeature(
      remoting.ClientPlugin.Feature.NOTIFY_CLIENT_RESOLUTION);
};

/** @return {{width:number, height:number, xDpi:number, yDpi:number}} */
remoting.ClientPlugin.HostDesktopImpl.prototype.getDimensions = function() {
  return {
    width: this.width_,
    height: this.height_,
    xDpi: this.xDpi_,
    yDpi: this.yDpi_
  };
};

/**
 * @param {number} width
 * @param {number} height
 * @param {number} deviceScale
 */
remoting.ClientPlugin.HostDesktopImpl.prototype.resize = function(
    width, height, deviceScale) {
  if (this.isResizable()) {
    var dpi = Math.floor(deviceScale * 96);
    this.postMessageCallback_({
      method: 'notifyClientResolution',
      data: {
        width: Math.floor(width * deviceScale),
        height: Math.floor(height * deviceScale),
        x_dpi: dpi,
        y_dpi: dpi
      }
    });
  }
};

/**
 * This function is called by |this.plugin_| when the size of the host
 * desktop is changed.
 *
 * @param {remoting.ClientPluginMessage} message
 */
remoting.ClientPlugin.HostDesktopImpl.prototype.onSizeUpdated = function(
    message) {
  this.width_ = getNumberAttr(message.data, 'width');
  this.height_ = getNumberAttr(message.data, 'height');
  this.xDpi_ = getNumberAttr(message.data, 'x_dpi', 96);
  this.yDpi_ = getNumberAttr(message.data, 'y_dpi', 96);
  this.raiseEvent(remoting.HostDesktop.Events.sizeChanged,
                  this.getDimensions());
};

/**
 * This function is called by |this.plugin_| when the shape of the host
 * desktop is changed.
 *
 * @param {remoting.ClientPluginMessage} message
 * @return {Array<{left:number, top:number, width:number, height:number}>}
 *    rectangles of the desktop shape.
 */
remoting.ClientPlugin.HostDesktopImpl.prototype.onShapeUpdated =
    function(message) {
  var shapes = getArrayAttr(message.data, 'rects');
  var rects = shapes.map(
    /** @param {Array.<number>} shape */
    function(shape) {
      if (!Array.isArray(shape) || shape.length != 4) {
        throw 'Received invalid onDesktopShape message';
      }
      var rect = {};
      rect.left = shape[0];
      rect.top = shape[1];
      rect.width = shape[2];
      rect.height = shape[3];
      return rect;
  });

  this.raiseEvent(remoting.HostDesktop.Events.shapeChanged, rects);
  return rects;
};

}());