// Copyright (c) 2009 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 CFInstall.js provides a set of utilities for managing
* the Chrome Frame detection and installation process.
* @author slightlyoff@google.com (Alex Russell)
*/
(function(scope) {
// bail if we'd be over-writing an existing CFInstall object
if (scope['CFInstall']) {
return;
}
/**
* returns an item based on DOM ID. Optionally a document may be provided to
* specify the scope to search in. If a node is passed, it's returned as-is.
* @param {string|Node} id The ID of the node to be located or a node
* @param {Node} doc Optional A document to search for id.
* @return {Node}
*/
var byId = function(id, doc) {
return (typeof id == 'string') ? (doc || document).getElementById(id) : id;
};
/////////////////////////////////////////////////////////////////////////////
// Plugin Detection
/////////////////////////////////////////////////////////////////////////////
/**
* Checks to find out if ChromeFrame is available as a plugin
* @return {Boolean}
*/
var isAvailable = function() {
// For testing purposes.
if (scope.CFInstall._force) {
return scope.CFInstall._forceValue;
}
// Look for CF in the User Agent before trying more expensive checks
var ua = navigator.userAgent.toLowerCase();
if (ua.indexOf("chromeframe") >= 0) {
return true;
}
if (typeof window['ActiveXObject'] != 'undefined') {
try {
var obj = new ActiveXObject('ChromeTab.ChromeFrame');
if (obj) {
obj.registerBhoIfNeeded();
return true;
}
} catch(e) {
// squelch
}
}
return false;
};
/**
* Creates a style sheet in the document containing the passed rules.
*/
var injectStyleSheet = function(rules) {
try {
var ss = document.createElement('style');
ss.setAttribute('type', 'text/css');
if (ss.styleSheet) {
ss.styleSheet.cssText = rules;
} else {
ss.appendChild(document.createTextNode(rules));
}
var h = document.getElementsByTagName('head')[0];
var firstChild = h.firstChild;
h.insertBefore(ss, firstChild);
} catch (e) {
// squelch
}
};
/** @type {boolean} */
var cfStyleTagInjected = false;
/** @type {boolean} */
var cfHiddenInjected = false;
/**
* Injects style rules into the document to handle formatting of Chrome Frame
* prompt. Multiple calls have no effect.
*/
var injectCFStyleTag = function() {
if (cfStyleTagInjected) {
// Once and only once
return;
}
var rules = '.chromeFrameInstallDefaultStyle {' +
'width: 800px;' +
'height: 600px;' +
'position: absolute;' +
'left: 50%;' +
'top: 50%;' +
'margin-left: -400px;' +
'margin-top: -300px;' +
'}' +
'.chromeFrameOverlayContent {' +
'position: absolute;' +
'margin-left: -400px;' +
'margin-top: -300px;' +
'left: 50%;' +
'top: 50%;' +
'border: 1px solid #93B4D9;' +
'background-color: white;' +
'z-index: 2001;' +
'}' +
'.chromeFrameOverlayContent iframe {' +
'width: 800px;' +
'height: 600px;' +
'border: none;' +
'}' +
'.chromeFrameOverlayCloseBar {' +
'height: 1em;' +
'text-align: right;' +
'background-color: #CADEF4;' +
'}' +
'.chromeFrameOverlayUnderlay {' +
'position: absolute;' +
'width: 100%;' +
'height: 100%;' +
'background-color: white;' +
'opacity: 0.5;' +
'-moz-opacity: 0.5;' +
'-webkit-opacity: 0.5;' +
'-ms-filter: ' +
'"progid:DXImageTransform.Microsoft.Alpha(Opacity=50)";' +
'filter: alpha(opacity=50);' +
'z-index: 2000;' +
'}';
injectStyleSheet(rules);
cfStyleTagInjected = true;
};
/**
* Injects style rules to hide the overlay version of the GCF prompt.
* Multiple calls have no effect.
*/
var closeOverlay = function() {
// IE has a limit to the # of <style> tags allowed, so we avoid
// tempting the fates.
if (cfHiddenInjected) {
return;
}
var rules = '.chromeFrameOverlayContent { display: none; }' +
'.chromeFrameOverlayUnderlay { display: none; }';
injectStyleSheet(rules);
// Hide the dialog for a year (or until cookies are deleted).
var age = 365 * 24 * 60 * 60 * 1000;
document.cookie = "disableGCFCheck=1;path=/;max-age="+age;
cfHiddenInjected = true;
};
/**
* Plucks properties from the passed arguments and sets them on the passed
* DOM node
* @param {Node} node The node to set properties on
* @param {Object} args A map of user-specified properties to set
*/
var setProperties = function(node, args) {
var srcNode = byId(args['node']);
node.id = args['id'] || (srcNode ? srcNode['id'] || getUid(srcNode) : '');
// TODO(slightlyoff): Opera compat? need to test there
var cssText = args['cssText'] || '';
node.style.cssText = ' ' + cssText;
var classText = args['className'] || '';
node.className = classText;
// default if the browser doesn't so we don't show sad-tab
var src = args['src'] || 'about:blank';
node.src = src;
if (srcNode) {
srcNode.parentNode.replaceChild(node, srcNode);
}
};
/**
* Creates an iframe.
* @param {Object} args A bag of configuration properties, including values
* like 'node', 'cssText', 'className', 'id', 'src', etc.
* @return {Node}
*/
var makeIframe = function(args) {
var el = document.createElement('iframe');
el.setAttribute('frameborder', '0');
el.setAttribute('border', '0');
setProperties(el, args);
return el;
};
/**
* Adds an unadorned iframe into the page, taking arguments to customize it.
* @param {Object} args A map of user-specified properties to set
*/
var makeInlinePrompt = function(args) {
args.className = 'chromeFrameInstallDefaultStyle ' +
(args.className || '');
var ifr = makeIframe(args);
// TODO(slightlyoff): handle placement more elegantly!
if (!ifr.parentNode) {
var firstChild = document.body.firstChild;
document.body.insertBefore(ifr, firstChild);
}
};
/**
* Adds a styled, closable iframe into the page with a background that
* emulates a modal dialog.
* @param {Object} args A map of user-specified properties to set
*/
var makeOverlayPrompt = function(args) {
if (byId('chromeFrameOverlayContent')) {
return; // Was previously created. Bail.
}
var n = document.createElement('span');
n.innerHTML = '<div class="chromeFrameOverlayUnderlay"></div>' +
'<table class="chromeFrameOverlayContent"' +
'id="chromeFrameOverlayContent"' +
'cellpadding="0" cellspacing="0">' +
'<tr class="chromeFrameOverlayCloseBar">' +
'<td>' +
// TODO(slightlyoff): i18n
'<button id="chromeFrameCloseButton">close</button>' +
'</td>' +
'</tr>' +
'<tr>' +
'<td id="chromeFrameIframeHolder"></td>' +
'</tr>' +
'</table>';
var b = document.body;
// Insert underlay nodes into the document in the right order.
while (n.firstChild) {
b.insertBefore(n.lastChild, b.firstChild);
}
var ifr = makeIframe(args);
byId('chromeFrameIframeHolder').appendChild(ifr);
byId('chromeFrameCloseButton').onclick = closeOverlay;
};
var CFInstall = {};
/**
* Checks to see if Chrome Frame is available, if not, prompts the user to
* install. Once installation is begun, a background timer starts,
* checkinging for a successful install every 2 seconds. Upon detection of
* successful installation, the current page is reloaded, or if a
* 'destination' parameter is passed, the page navigates there instead.
* @param {Object} args A bag of configuration properties. Respected
* properties are: 'mode', 'url', 'destination', 'node', 'onmissing',
* 'preventPrompt', 'oninstall', 'preventInstallDetection', 'cssText', and
* 'className'.
* @public
*/
CFInstall.check = function(args) {
args = args || {};
// We currently only support CF in IE
// TODO(slightlyoff): Update this should we support other browsers!
var ua = navigator.userAgent;
var ieRe = /MSIE (\S+); Windows NT/;
var bail = false;
if (ieRe.test(ua)) {
// We also only support Win2003/XPSP2 or better. See:
// http://msdn.microsoft.com/en-us/library/ms537503%28VS.85%29.aspx
if (parseFloat(ieRe.exec(ua)[1]) < 6 &&
// 'SV1' indicates SP2, only bail if not SP2 or Win2K3
ua.indexOf('SV1') < 0) {
bail = true;
}
} else {
// Not IE
bail = true;
}
if (bail) {
return;
}
// Inject the default styles
injectCFStyleTag();
if (document.cookie.indexOf("disableGCFCheck=1") >=0) {
// If we're supposed to hide the overlay prompt, add the rules to do it.
closeOverlay();
}
// When loaded in an alternate protocol (e.g., "file:"), still call out to
// the right location.
var currentProtocol = document.location.protocol;
var protocol = (currentProtocol == 'https:') ? 'https:' : 'http:';
// TODO(slightlyoff): Update this URL when a mini-installer page is
// available.
var installUrl = protocol + '//www.google.com/chromeframe';
if (!isAvailable()) {
if (args.onmissing) {
args.onmissing();
}
args.src = args.url || installUrl;
var mode = args.mode || 'inline';
var preventPrompt = args.preventPrompt || false;
if (!preventPrompt) {
if (mode == 'inline') {
makeInlinePrompt(args);
} else if (mode == 'overlay') {
makeOverlayPrompt(args);
} else {
window.open(args.src);
}
}
if (args.preventInstallDetection) {
return;
}
// Begin polling for install success.
var installTimer = setInterval(function() {
// every 2 seconds, look to see if CF is available, if so, proceed on
// to our destination
if (isAvailable()) {
if (args.oninstall) {
args.oninstall();
}
clearInterval(installTimer);
// TODO(slightlyoff): add a way to prevent navigation or make it
// contingent on oninstall?
window.location = args.destination || window.location;
}
}, 2000);
}
};
CFInstall._force = false;
CFInstall._forceValue = false;
CFInstall.isAvailable = isAvailable;
// expose CFInstall to the external scope. We've already checked to make
// sure we're not going to blow existing objects away.
scope.CFInstall = CFInstall;
})(this['ChromeFrameInstallScope'] || this);