annotate johndyer-mediaelement-13fa20a/src/js/me-shim.js @ 25:4a4bd554b4c1 tip

Closing this sub branch.

// Handles calls from Flash/Silverlight and reports them as native <video/audio> events and properties
mejs.MediaPluginBridge = {

	pluginMediaElements:{},
	htmlMediaElements:{},

	registerPluginElement: function (id, pluginMediaElement, htmlMediaElement) {
		this.pluginMediaElements[id] = pluginMediaElement;
		this.htmlMediaElements[id] = htmlMediaElement;
	},

	// when Flash/Silverlight is ready, it calls out to this method
	initPlugin: function (id) {

		var pluginMediaElement = this.pluginMediaElements[id],
			htmlMediaElement = this.htmlMediaElements[id];

		// find the javascript bridge
		switch (pluginMediaElement.pluginType) {
			case "flash":
				pluginMediaElement.pluginElement = pluginMediaElement.pluginApi = document.getElementById(id);
				break;
			case "silverlight":
				pluginMediaElement.pluginElement = document.getElementById(pluginMediaElement.id);
				pluginMediaElement.pluginApi = pluginMediaElement.pluginElement.Content.MediaElementJS;
				break;
		}

		if (pluginMediaElement.pluginApi != null && pluginMediaElement.success) {
			pluginMediaElement.success(pluginMediaElement, htmlMediaElement);
		}
	},

	// receives events from Flash/Silverlight and sends them out as HTML5 media events
	// http://www.whatwg.org/specs/web-apps/current-work/multipage/video.html
	fireEvent: function (id, eventName, values) {

		var
			e,
			i,
			bufferedTime,
			pluginMediaElement = this.pluginMediaElements[id];

		pluginMediaElement.ended = false;
		pluginMediaElement.paused = true;

		// fake event object to mimic real HTML media event.
		e = {
			type: eventName,
			target: pluginMediaElement
		};

		// attach all values to element and event object
		for (i in values) {
			pluginMediaElement[i] = values[i];
			e[i] = values[i];
		}

		// fake the newer W3C buffered TimeRange (loaded and total have been removed)
		bufferedTime = values.bufferedTime || 0;

		e.target.buffered = e.buffered = {
			start: function(index) {
				return 0;
			},
			end: function (index) {
				return bufferedTime;
			},
			length: 1
		};

		pluginMediaElement.dispatchEvent(e.type, e);
	}
};

/*
Default options
*/
mejs.MediaElementDefaults = {
	// allows testing on HTML5, flash, silverlight
	// auto: attempts to detect what the browser can do
	// native: forces HTML5 playback
	// shim: disallows HTML5, will attempt either Flash or Silverlight
	// none: forces fallback view
	mode: 'auto',
	// remove or reorder to change plugin priority and availability
	plugins: ['flash','silverlight'],
	// shows debug errors on screen
	enablePluginDebug: false,
	// overrides the type specified, useful for dynamic instantiation
	type: '',
	// path to Flash and Silverlight plugins
	pluginPath: mejs.Utility.getScriptPath(['mediaelement.js','mediaelement.min.js','mediaelement-and-player.js','mediaelement-and-player.min.js']),
	// name of flash file
	flashName: 'flashmediaelement.swf',
	// turns on the smoothing filter in Flash
	enablePluginSmoothing: false,
	// name of silverlight file
	silverlightName: 'silverlightmediaelement.xap',
	// default if the <video width> is not specified
	defaultVideoWidth: 480,
	// default if the <video height> is not specified
	defaultVideoHeight: 270,
	// overrides <video width>
	pluginWidth: -1,
	// overrides <video height>
	pluginHeight: -1,
	// rate in milliseconds for Flash and Silverlight to fire the timeupdate event
	// larger number is less accurate, but less strain on plugin->JavaScript bridge
	timerRate: 250,
	success: function () { },
	error: function () { }
};

/*
Determines if a browser supports the <video> or <audio> element
and returns either the native element or a Flash/Silverlight version that
mimics HTML5 MediaElement
*/
mejs.MediaElement = function (el, o) {
	return mejs.HtmlMediaElementShim.create(el,o);
};

mejs.HtmlMediaElementShim = {

	create: function(el, o) {
		var
			options = mejs.MediaElementDefaults,
			htmlMediaElement = (typeof(el) == 'string') ? document.getElementById(el) : el,
			tagName = htmlMediaElement.tagName.toLowerCase(),
			isMediaTag = (tagName == 'audio' || tagName == 'video'),
			src = htmlMediaElement.getAttribute('src'),
			poster = htmlMediaElement.getAttribute('poster'),
			autoplay =  htmlMediaElement.getAttribute('autoplay'),
			preload =  htmlMediaElement.getAttribute('preload'),
			controls =  htmlMediaElement.getAttribute('controls'),
			playback,
			prop;

		// extend options
		for (prop in o) {
			options[prop] = o[prop];
		}

					
		// is this a true HTML5 media element
		if (isMediaTag) {
			isVideo = (htmlMediaElement.tagName.toLowerCase() == 'video');
		} else {
			// fake source from <a href=""></a>
			src = htmlMediaElement.getAttribute('href');		
		}

		// clean up attributes
		src = (src == 'undefined' || src == '' || src === null) ? null : src;		
		poster = (typeof poster == 'undefined' || poster === null) ? '' : poster;
		preload = (typeof preload == 'undefined' || preload === null || preload === 'false') ? 'none' : preload;
		autoplay = !(typeof autoplay == 'undefined' || autoplay === null || autoplay === 'false');
		controls = !(typeof controls == 'undefined' || controls === null || controls === 'false');

		// test for HTML5 and plugin capabilities
		playback = this.determinePlayback(htmlMediaElement, options, mejs.MediaFeatures.supportsMediaTag, isMediaTag, src);

		if (playback.method == 'native') {
			// second fix for android
			if (mejs.MediaFeatures.isBustedAndroid) {
				htmlMediaElement.src = playback.url;
				htmlMediaElement.addEventListener('click', function() {
						htmlMediaElement.play();
				}, true);
			}
		
			// add methods to native HTMLMediaElement
			return this.updateNative( playback.htmlMediaElement, options, autoplay, preload, playback);
		} else if (playback.method !== '') {
			// create plugin to mimic HTMLMediaElement
			return this.createPlugin( htmlMediaElement, options, playback.method, (playback.url !== null) ? mejs.Utility.absolutizeUrl(playback.url) : '', poster, autoplay, preload, controls);
		} else {
			// boo, no HTML5, no Flash, no Silverlight.
			this.createErrorMessage( htmlMediaElement, options, (playback.url !== null) ? mejs.Utility.absolutizeUrl(playback.url) : '', poster );
		}
	},
	
	videoRegExp: /(mp4|m4v|ogg|ogv|webm|flv|wmv|mpeg)/gi,
	
	determinePlayback: function(htmlMediaElement, options, supportsMediaTag, isMediaTag, src) {
		var
			mediaFiles = [],
			i,
			j,
			k,
			l,
			n,
			type,
			result = { method: '', url: '', htmlMediaElement: htmlMediaElement, isVideo: (htmlMediaElement.tagName.toLowerCase() != 'audio')},
			pluginName,
			pluginVersions,
			pluginInfo,
			dummy;
			
		// STEP 1: Get URL and type from <video src> or <source src>

		// supplied type overrides <video type> and <source type>
		if (typeof options.type != 'undefined' && options.type !== '') {
			
			// accept either string or array of types
			if (typeof options.type == 'string') {
				mediaFiles.push({type:options.type, url:src});
			} else {
				
				for (i=0; i<options.type.length; i++) {
					mediaFiles.push({type:options.type[i], url:src});
				}
			}

		// test for src attribute first
		} else if (src !== null) {
			type = this.formatType(src, htmlMediaElement.getAttribute('type'));
			mediaFiles.push({type:type, url:src});

		// then test for <source> elements
		} else {
			// test <source> types to see if they are usable
			for (i = 0; i < htmlMediaElement.childNodes.length; i++) {
				n = htmlMediaElement.childNodes[i];
				if (n.nodeType == 1 && n.tagName.toLowerCase() == 'source') {
					src = n.getAttribute('src');
					type = this.formatType(src, n.getAttribute('type'));
					mediaFiles.push({type:type, url:src});
				}
			}
		}

		// STEP 2: Test for playback method
		
		// special case for Android which sadly doesn't implement the canPlayType function (always returns '')
		if (mejs.MediaFeatures.isBustedAndroid) {
			htmlMediaElement.canPlayType = function(type) {
				return (type.match(/video\/(mp4|m4v)/gi) !== null) ? 'maybe' : '';
			};
		}		
		

		// test for native playback first
		if (supportsMediaTag && (options.mode === 'auto' || options.mode === 'native')) {
						
			if (!isMediaTag) {
				var tagName = 'video';
				if (mediaFiles.length > 0 && mediaFiles[0].url !== null && this.getTypeFromFile(mediaFiles[0].url).indexOf('audio') > -1) {
					tagName = 'audio';
					result.isVideo = false;
				}
				
				// create a real HTML5 Media Element 
				dummy = document.createElement(tagName);			
				htmlMediaElement.parentNode.insertBefore(dummy, htmlMediaElement);
				htmlMediaElement.style.display = 'none';
				
				// use this one from now on
				result.htmlMediaElement = htmlMediaElement = dummy;
			}
				
			for (i=0; i<mediaFiles.length; i++) {
				// normal check
				if (htmlMediaElement.canPlayType(mediaFiles[i].type).replace(/no/, '') !== '' 
					// special case for Mac/Safari 5.0.3 which answers '' to canPlayType('audio/mp3') but 'maybe' to canPlayType('audio/mpeg')
					|| htmlMediaElement.canPlayType(mediaFiles[i].type.replace(/mp3/,'mpeg')).replace(/no/, '') !== '') {
					result.method = 'native';
					result.url = mediaFiles[i].url;
					break;
				}
			}			
			
			if (result.method === 'native') {
				return result;
			}
		}

		// if native playback didn't work, then test plugins
		if (options.mode === 'auto' || options.mode === 'shim') {
			for (i=0; i<mediaFiles.length; i++) {
				type = mediaFiles[i].type;

				// test all plugins in order of preference [silverlight, flash]
				for (j=0; j<options.plugins.length; j++) {

					pluginName = options.plugins[j];

					// test version of plugin (for future features)
					pluginVersions = mejs.plugins[pluginName];
					for (k=0; k<pluginVersions.length; k++) {
						pluginInfo = pluginVersions[k];

						// test if user has the correct plugin version
						if (mejs.PluginDetector.hasPluginVersion(pluginName, pluginInfo.version)) {

							// test for plugin playback types
							for (l=0; l<pluginInfo.types.length; l++) {
								// find plugin that can play the type
								if (type == pluginInfo.types[l]) {
									result.method = pluginName;
									result.url = mediaFiles[i].url;
									return result;
								}
							}
						}
					}
				}
			}
		}
		
		// what if there's nothing to play? just grab the first available
		if (result.method === '') {
			result.url = mediaFiles[0].url;
		}

		return result;
	},

	formatType: function(url, type) {
		var ext;

		// if no type is supplied, fake it with the extension
		if (url && !type) {		
			return this.getTypeFromFile(url);
		} else {
			// only return the mime part of the type in case the attribute contains the codec
			// see http://www.whatwg.org/specs/web-apps/current-work/multipage/video.html#the-source-element
			// `video/mp4; codecs="avc1.42E01E, mp4a.40.2"` becomes `video/mp4`
			
			if (type && ~type.indexOf(';')) {
				return type.substr(0, type.indexOf(';')); 
			} else {
				return type;
			}
		}
	},
	
	getTypeFromFile: function(url) {
		var ext = url.substring(url.lastIndexOf('.') + 1);
		return (this.videoRegExp.test(ext) ? 'video' : 'audio') + '/' + ext;
	},

	createErrorMessage: function(htmlMediaElement, options, downloadUrl, poster) {
		var errorContainer = document.createElement('div');
		errorContainer.className = 'me-cannotplay';

		try {
			errorContainer.style.width = htmlMediaElement.width + 'px';
			errorContainer.style.height = htmlMediaElement.height + 'px';
		} catch (e) {}

		errorContainer.innerHTML = (poster !== '') ?
			'<a href="' + downloadUrl + '"><img src="' + poster + '" /></a>' :
			'<a href="' + downloadUrl + '"><span>Download File</span></a>';

		htmlMediaElement.parentNode.insertBefore(errorContainer, htmlMediaElement);
		htmlMediaElement.style.display = 'none';

		options.error(htmlMediaElement);
	},

	createPlugin:function(htmlMediaElement, options, isVideo, pluginType, mediaUrl, poster, autoplay, preload, controls) {
		var width = 1,
			height = 1,
			pluginid = 'me_' + pluginType + '_' + (mejs.meIndex++),
			pluginMediaElement = new mejs.PluginMediaElement(pluginid, pluginType, mediaUrl),
			container = document.createElement('div'),
			specialIEContainer,
			node,
			initVars;

		// check for placement inside a <p> tag (sometimes WYSIWYG editors do this)
		node = htmlMediaElement.parentNode;
		while (node !== null && node.tagName.toLowerCase() != 'body') {
			if (node.parentNode.tagName.toLowerCase() == 'p') {
				node.parentNode.parentNode.insertBefore(node, node.parentNode);
				break;
			}
			node = node.parentNode;
		}

		if (isVideo) {
			width = (options.videoWidth > 0) ? options.videoWidth : (htmlMediaElement.getAttribute('width') !== null) ? htmlMediaElement.getAttribute('width') : options.defaultVideoWidth;
			height = (options.videoHeight > 0) ? options.videoHeight : (htmlMediaElement.getAttribute('height') !== null) ? htmlMediaElement.getAttribute('height') : options.defaultVideoHeight;
		} else {
			if (options.enablePluginDebug) {
				width = 320;
				height = 240;
			}
		}

		// register plugin
		pluginMediaElement.success = options.success;
		mejs.MediaPluginBridge.registerPluginElement(pluginid, pluginMediaElement, htmlMediaElement);

		// add container (must be added to DOM before inserting HTML for IE)
		container.className = 'me-plugin';
		htmlMediaElement.parentNode.insertBefore(container, htmlMediaElement);

		// flash/silverlight vars
		initVars = [
			'id=' + pluginid,
			'isvideo=' + ((isVideo) ? "true" : "false"),
			'autoplay=' + ((autoplay) ? "true" : "false"),
			'preload=' + preload,
			'width=' + width,
			'startvolume=' + options.startVolume,
			'timerrate=' + options.timerRate,
			'height=' + height];

		if (mediaUrl !== null) {
			if (pluginType == 'flash') {
				initVars.push('file=' + mejs.Utility.encodeUrl(mediaUrl));
			} else {
				initVars.push('file=' + mediaUrl);
			}
		}
		if (options.enablePluginDebug) {
			initVars.push('debug=true');
		}
		if (options.enablePluginSmoothing) {
			initVars.push('smoothing=true');
		}
		if (controls) {
			initVars.push('controls=true'); // shows controls in the plugin if desired
		}

		switch (pluginType) {
			case 'silverlight':
				container.innerHTML =
'<object data="data:application/x-silverlight-2," type="application/x-silverlight-2" id="' + pluginid + '" name="' + pluginid + '" width="' + width + '" height="' + height + '">' +
'<param name="initParams" value="' + initVars.join(',') + '" />' +
'<param name="windowless" value="true" />' +
'<param name="background" value="black" />' +
'<param name="minRuntimeVersion" value="3.0.0.0" />' +
'<param name="autoUpgrade" value="true" />' +
'<param name="source" value="' + options.pluginPath + options.silverlightName + '" />' +
'</object>';
					break;

			case 'flash':

				if (mejs.MediaFeatures.isIE) {
					specialIEContainer = document.createElement('div');
					container.appendChild(specialIEContainer);
					specialIEContainer.outerHTML =
'<object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000" codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab" ' +
'id="' + pluginid + '" width="' + width + '" height="' + height + '">' +
'<param name="movie" value="' + options.pluginPath + options.flashName + '?x=' + (new Date()) + '" />' +
'<param name="flashvars" value="' + initVars.join('&amp;') + '" />' +
'<param name="quality" value="high" />' +
'<param name="bgcolor" value="#000000" />' +
'<param name="wmode" value="transparent" />' +
'<param name="allowScriptAccess" value="always" />' +
'<param name="allowFullScreen" value="true" />' +
'</object>';

				} else {

					container.innerHTML =
'<embed id="' + pluginid + '" name="' + pluginid + '" ' +
'play="true" ' +
'loop="false" ' +
'quality="high" ' +
'bgcolor="#000000" ' +
'wmode="transparent" ' +
'allowScriptAccess="always" ' +
'allowFullScreen="true" ' +
'type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" ' +
'src="' + options.pluginPath + options.flashName + '" ' +
'flashvars="' + initVars.join('&') + '" ' +
'width="' + width + '" ' +
'height="' + height + '"></embed>';
				}
				break;
		}
		// hide original element
		htmlMediaElement.style.display = 'none';

		// FYI: options.success will be fired by the MediaPluginBridge
		
		return pluginMediaElement;
	},

	updateNative: function(htmlMediaElement, options, autoplay, preload, playback) {
		// add methods to video object to bring it into parity with Flash Object
		for (var m in mejs.HtmlMediaElement) {
			htmlMediaElement[m] = mejs.HtmlMediaElement[m];
		}

		/*
		Chrome now supports preload="none"
		if (mejs.MediaFeatures.isChrome) {
		
			// special case to enforce preload attribute (Chrome doesn't respect this)
			if (preload === 'none' && !autoplay) {
			
				// forces the browser to stop loading (note: fails in IE9)
				htmlMediaElement.src = '';
				htmlMediaElement.load();
				htmlMediaElement.canceledPreload = true;

				htmlMediaElement.addEventListener('play',function() {
					if (htmlMediaElement.canceledPreload) {
						htmlMediaElement.src = playback.url;
						htmlMediaElement.load();
						htmlMediaElement.play();
						htmlMediaElement.canceledPreload = false;
					}
				}, false);
			// for some reason Chrome forgets how to autoplay sometimes.
			} else if (autoplay) {
				htmlMediaElement.load();
				htmlMediaElement.play();
			}
		}
		*/

		// fire success code
		options.success(htmlMediaElement, htmlMediaElement);
		
		return htmlMediaElement;
	}
};

window.mejs = mejs;
window.MediaElement = mejs.MediaElement;