jiti-meet/desktopsharing.js

318 lines
10 KiB
JavaScript

/* global $, alert, changeLocalVideo, chrome, config, connection, getConferenceHandler, getUserMediaWithConstraints, VideoLayout */
/**
* Indicates that desktop stream is currently in use(for toggle purpose).
* @type {boolean}
*/
var isUsingScreenStream = false;
/**
* Indicates that switch stream operation is in progress and prevent from triggering new events.
* @type {boolean}
*/
var switchInProgress = false;
/**
* Method used to get screen sharing stream.
*
* @type {function (stream_callback, failure_callback}
*/
var obtainDesktopStream = null;
/**
* Flag used to cache desktop sharing enabled state. Do not use directly as it can be <tt>null</tt>.
* @type {null|boolean}
*/
var _desktopSharingEnabled = null;
/**
* Method obtains desktop stream from WebRTC 'screen' source.
* Flag 'chrome://flags/#enable-usermedia-screen-capture' must be enabled.
*/
function obtainWebRTCScreen(streamCallback, failCallback) {
getUserMediaWithConstraints(
['screen'],
streamCallback,
failCallback
);
}
/**
* Constructs inline install URL for Chrome desktop streaming extension.
* The 'chromeExtensionId' must be defined in config.js.
* @returns {string}
*/
function getWebStoreInstallUrl()
{
return "https://chrome.google.com/webstore/detail/" + config.chromeExtensionId;
}
/**
* Checks whether extension update is required.
* @param minVersion minimal required version
* @param extVersion current extension version
* @returns {boolean}
*/
function isUpdateRequired(minVersion, extVersion)
{
try
{
var s1 = minVersion.split('.');
var s2 = extVersion.split('.');
var len = Math.max(s1.length, s2.length);
for (var i = 0; i < len; i++)
{
var n1 = 0,
n2 = 0;
if (i < s1.length)
n1 = parseInt(s1[i]);
if (i < s2.length)
n2 = parseInt(s2[i]);
if (isNaN(n1) || isNaN(n2))
{
return true;
}
else if (n1 !== n2)
{
return n1 > n2;
}
}
// will happen if boths version has identical numbers in
// their components (even if one of them is longer, has more components)
return false;
}
catch (e)
{
console.error("Failed to parse extension version", e);
messageHandler.showError('Error',
'Error when trying to detect desktopsharing extension.');
return true;
}
}
function checkExtInstalled(isInstalledCallback) {
if (!chrome.runtime) {
// No API, so no extension for sure
isInstalledCallback(false);
return;
}
chrome.runtime.sendMessage(
config.chromeExtensionId,
{ getVersion: true },
function (response) {
if (!response || !response.version) {
// Communication failure - assume that no endpoint exists
console.warn("Extension not installed?: " + chrome.runtime.lastError);
isInstalledCallback(false);
} else {
// Check installed extension version
var extVersion = response.version;
console.log('Extension version is: ' + extVersion);
var updateRequired = isUpdateRequired(config.minChromeExtVersion, extVersion);
if (updateRequired) {
alert(
'Jitsi Desktop Streamer requires update. ' +
'Changes will take effect after next Chrome restart.');
}
isInstalledCallback(!updateRequired);
}
}
);
}
function doGetStreamFromExtension(streamCallback, failCallback) {
// Sends 'getStream' msg to the extension. Extension id must be defined in the config.
chrome.runtime.sendMessage(
config.chromeExtensionId,
{ getStream: true, sources: config.desktopSharingSources },
function (response) {
if (!response) {
failCallback(chrome.runtime.lastError);
return;
}
console.log("Response from extension: " + response);
if (response.streamId) {
getUserMediaWithConstraints(
['desktop'],
function (stream) {
streamCallback(stream);
},
failCallback,
null, null, null,
response.streamId);
} else {
failCallback("Extension failed to get the stream");
}
}
);
}
/**
* Asks Chrome extension to call chooseDesktopMedia and gets chrome 'desktop' stream for returned stream token.
*/
function obtainScreenFromExtension(streamCallback, failCallback) {
checkExtInstalled(
function (isInstalled) {
if (isInstalled) {
doGetStreamFromExtension(streamCallback, failCallback);
} else {
chrome.webstore.install(
getWebStoreInstallUrl(),
function (arg) {
console.log("Extension installed successfully", arg);
// We need to reload the page in order to get the access to chrome.runtime
window.location.reload(false);
},
function (arg) {
console.log("Failed to install the extension", arg);
failCallback(arg);
messageHandler.showError('Error',
'Failed to install desktop sharing extension');
}
);
}
}
);
}
/**
* @returns {boolean} <tt>true</tt> if desktop sharing feature is available and enabled.
*/
function isDesktopSharingEnabled() {
if (_desktopSharingEnabled === null) {
if (obtainDesktopStream === obtainScreenFromExtension) {
// Parse chrome version
var userAgent = navigator.userAgent.toLowerCase();
// We can assume that user agent is chrome, because it's enforced when 'ext' streaming method is set
var ver = parseInt(userAgent.match(/chrome\/(\d+)\./)[1], 10);
console.log("Chrome version" + userAgent, ver);
_desktopSharingEnabled = ver >= 34;
} else {
_desktopSharingEnabled = obtainDesktopStream === obtainWebRTCScreen;
}
}
return _desktopSharingEnabled;
}
function showDesktopSharingButton() {
if (isDesktopSharingEnabled()) {
$('#desktopsharing').css({display: "inline"});
} else {
$('#desktopsharing').css({display: "none"});
}
}
/**
* Call this method to toggle desktop sharing feature.
* @param method pass "ext" to use chrome extension for desktop capture(chrome extension required),
* pass "webrtc" to use WebRTC "screen" desktop source('chrome://flags/#enable-usermedia-screen-capture'
* must be enabled), pass any other string or nothing in order to disable this feature completely.
*/
function setDesktopSharing(method) {
// Check if we are running chrome
if (!navigator.webkitGetUserMedia) {
obtainDesktopStream = null;
console.info("Desktop sharing disabled");
} else if (method == "ext") {
obtainDesktopStream = obtainScreenFromExtension;
console.info("Using Chrome extension for desktop sharing");
} else if (method == "webrtc") {
obtainDesktopStream = obtainWebRTCScreen;
console.info("Using Chrome WebRTC for desktop sharing");
}
// Reset enabled cache
_desktopSharingEnabled = null;
showDesktopSharingButton();
}
/**
* Initializes <link rel=chrome-webstore-item /> with extension id set in config.js to support inline installs.
* Host site must be selected as main website of published extension.
*/
function initInlineInstalls()
{
$("link[rel=chrome-webstore-item]").attr("href", getWebStoreInstallUrl());
}
function getSwitchStreamFailed(error) {
console.error("Failed to obtain the stream to switch to", error);
switchInProgress = false;
}
function streamSwitchDone() {
//window.setTimeout(
// function () {
switchInProgress = false;
Toolbar.changeDesktopSharingButtonState(isUsingScreenStream);
// }, 100
//);
}
function newStreamCreated(stream) {
var oldStream = connection.jingle.localVideo;
connection.jingle.localVideo = stream;
VideoLayout.changeLocalVideo(stream, !isUsingScreenStream);
var conferenceHandler = getConferenceHandler();
if (conferenceHandler) {
// FIXME: will block switchInProgress on true value in case of exception
conferenceHandler.switchStreams(stream, oldStream, streamSwitchDone);
} else {
// We are done immediately
console.error("No conference handler");
messageHandler.showError('Error',
'Unable to switch video stream.');
streamSwitchDone();
}
}
/*
* Toggles screen sharing.
*/
function toggleScreenSharing() {
if (switchInProgress || !obtainDesktopStream) {
console.warn("Switch in progress or no method defined");
return;
}
switchInProgress = true;
if (!isUsingScreenStream)
{
// Switch to desktop stream
obtainDesktopStream(
function (stream) {
// We now use screen stream
isUsingScreenStream = true;
// Hook 'ended' event to restore camera when screen stream stops
stream.addEventListener('ended',
function (e) {
if (!switchInProgress && isUsingScreenStream) {
toggleScreenSharing();
}
}
);
newStreamCreated(stream);
},
getSwitchStreamFailed);
} else {
// Disable screen stream
getUserMediaWithConstraints(
['video'],
function (stream) {
// We are now using camera stream
isUsingScreenStream = false;
newStreamCreated(stream);
},
getSwitchStreamFailed, config.resolution || '360'
);
}
}