docs/html/videos/index.jd

videos=true
page.title=Videos
@jd:body

<script src="http://swfobject.googlecode.com/svn/trunk/swfobject/swfobject.js" type="text/javascript"></script>
<script src="{@docRoot}assets/jquery-history.js" type="text/javascript"></script>
<script type="text/javascript">
// for debugging in FF, so other browsers ignore the console commands.
var console;
if (!console) console = { 'log': function() {} };

/* This 'playlist' object defines the playlist IDs for each tab.
 * Each name inside 'playlist' corresponds to class names for the tab that the playlists belong to (eg: "googleioTab" and "googleioBox" divs).
 * Each string in 'ids' is the ID of a YouTube playlist that belongs in the corresponding tab.
 */
var playlists = {
  'googleio' : {
    'ids': ["734A052F802C96B9"]
  },
  'about' : {
    'ids': ["D7C64411AF40DEA5","611F8C5DBF49CEC6"]
  },
  'developertips' : {
    'ids': ["43E15866EF0033A2"]
  },
  'developersandbox' : {
    'ids': ["77426907BBAD558E"]
  }
};

/* Some playlists include the title in the description meta-data, so we need to account for this when building the thumbnail lists, so we don't show the title twice
 * This string is read via indexOf(), so multiple IDs need only be comma-separated in this string.
 */
var playlistsWithTitleInDescription = "734A052F802C96B9";

/* This 'featured' object defines the Feature Videos list. 
 * Each playlist ID is paired with a custom video description.
 */
var featured = {
// Android 2.0 Release
  'opZ69P-0Jbc' : "The Android 2.0 platform adds exciting new user features and developer APIs. Here's an introduction to what's new.",
// How to Make your Android UI Fast..
  'N6YdwzAvwOA' : "Make your user interface fast, with more efficient AdapterViews, better bitmap scaling, faster redrawing, ViewStub layouts, fewer Views, and more.", 
// How Do I Code Thee?
  'GARMe7Km_gk' : "If you'd like to augment your Android applications with pieces written in JavaScript or native code, watch this video."
};

/* When an event on the browser history occurs (back, forward, load),
 * load the video found in the URL hash 
 */
$(window).history(function(e, hash) {
  if (location.href.indexOf("#v=") != -1) {
    videoId = location.href.split("#v=");
    clickVideo(videoId[1]); // click the link with a matching class
  }
});

/* Load a video into the player box.
 * @param id        The YouTube video ID
 * @param title     The video title to display in the player box (character escaped)
 * @param autoplay  Whether to automatically play the video 
 */
function loadVideo(id, title, autoplay) {
  if($("." + id).hasClass("noplay")) {
  	console.log("noplay");
  	autoplay = false;
  	$("." + id).removeClass("noplay");
  }
  swfobject.embedSWF('http://www.youtube.com/v/' + id + '&rel=1&border=0&fs=1&autoplay=' + 
      (autoplay?1:0), 'player', '500', '334', '9.0.0', false, false, {allowfullscreen: 'true'});
  $("#videoPlayerTitle").html("<h2>" + unescape(title) + "</h2>");
  
  $.history.add('v=' + id); // add the current video to the browser history
  document.getElementById("doc-content").scrollTop = 0; // scroll the window to the top 
}

/* Draw all videos from a playlist into a 'videoPreviews' list
 * @param data  The feed data returned from the youtube request
 */
function renderPlaylist(data) {  
  var MAX_DESC_LENGTH = 390; // the length at which we will trim the description
  var feed = data.feed;
  var entries = feed.entry || [];
  var playlistId = feed.yt$playlistId.$t;
  
  var ul = $('<ul class="videoPreviews" />');
  
  // Loop through each entry (each video) and add it to the 'videoPreviews' list
  for (var i = 0; i < entries.length; i++) {
    var entry = entries[i];
    
    var title = entry.title.$t;
    var id = entry.media$group.yt$videoid.$t;
    var thumbUrl = entry.media$group.media$thumbnail[0].url;
    var fullDescription = entry.media$group.media$description.$t;
    var playerUrl = entry.media$group.media$content[0].url;
      
    // Check whether this playlist includes the video title inside the description meta-data, so we can remove it
    if (playlistsWithTitleInDescription.indexOf(playlistId) != -1) {
      var lines = fullDescription.split("\n");
      // If the first line includes the first 17 chars from the title, let's use the title from the description instead (because it's a more complete title)
      // This accounts for, literally, "Google I/O 2009 -", which is (so far) the min AND max for properly identifying a title in the only playlist with titles in the description
      if (lines[0].indexOf(title.slice(0,16)) != -1) {  
			h3Title = "<h3>" + lines[0] + "</h3>"; 	
      	if (lines[2].length < 30) lines = lines.slice(3);  // also, if the second line is very short (the speaker name), slice it out too
      	else lines = lines.slice(1);  // otherwise, slice after the first line
      }
      fullDescription = lines.join("");
    } 
    
    var shortDescription = fullDescription.substr(0, MAX_DESC_LENGTH);
    shortDescription += shortDescription.length == MAX_DESC_LENGTH ? "..." : ""; // add ellipsis if we've chopped the description
  
    var img = $('<img src="' + thumbUrl + '" width="120" height="90"/>');
    var a = $('<a class="' + id + '" href="#" onclick="loadVideo(\'' + id + '\',\'' + escape(title) + '\',true); return setSelected(this);" />');
    var pShortDescription = $('<p class="short">' + shortDescription + '</p>');
    var pFullDescription = $('<p class="full">' + fullDescription + '</p>');
    var h3Title = "<h3>" + title + "</h3>";
    var pToggle = "<p class='toggle'><a href='#' onclick='return toggleDescription(this)'><span class='more'>more</span><span class='less'>less</span></a></p>";
    var li = $('<li/>');
    
    li.append(a);
    a.append(img).append(h3Title).append(pShortDescription);
    
    // Add the full description and "more/less" toggle, if necessary
    if (fullDescription.length > MAX_DESC_LENGTH) {
    	a.append(pFullDescription);
    	li.append(pToggle);
    }
    
    ul.append(li);
  }
  
  // Now add the 'videoPreviews' list to the page, and be sure we put it in the right tab
  // This is the part that allows us to put multiple playlists in one tab
  for (var x in playlists) {
    var ids = playlists[x].ids;
    for (var i in ids) {
      if (ids[i] == playlistId) {
        $("#"+x+"Box").append(ul);
        break;
      }
    }
  }  
}

/* Draw a featured video into the existing 'videoPreviews' list 
 * @param data  The video data returned from the youtube request
 */
function renderFeatured(data) {  
  var MAX_TITLE_LENGTH = 48;
  var entry = data.entry || [];
  var id = entry.media$group.yt$videoid.$t;
  var description = featured[id];
  var title = entry.title.$t;
  var thumbUrl = entry.media$group.media$thumbnail[0].url;
  var playerUrl = entry.media$group.media$content[0].url;
  
  var ellipsis = title.length > MAX_TITLE_LENGTH ? "..." : "";
    
  var h3Title = "<h3>"+ title.substr(0,MAX_TITLE_LENGTH) + ellipsis + "</h3>";
  var img = $('<img src="' + thumbUrl + '" width="120" height="90"/>');
  var p = $('<p>' + description + '</p>');
  var a = $('<a class="' + id + '" href="#" onclick="loadVideo(\'' + id + '\',\'' + title + '\',true); return setSelected(this);" />');
  var li = $("<li/>");
  
  a.append(h3Title).append(img).append(p);
  li.append(a);

  $("#mainBodyRight .videoPreviews").append(li);
}

/* Request the playlist feeds from YouTube */
function showPlaylists() {
  for (var x in playlists) {
    var ids = playlists[x].ids;
    for (var i in ids) {
      var script = "<script type='text/javascript' src='http://gdata.youtube.com/feeds/api/playlists/" 
      				  + ids[i] + 
      				  "?v=2&alt=json-in-script&callback=renderPlaylist'><\/script>";
    	$("body").append(script);
    }
  }
}

/* Request the featured videos from YouTube */
function showFeatured() {
  for (var id in featured) {
    var script = "<script type='text/javascript' src='http://gdata.youtube.com/feeds/api/videos/" 
    					+ id + 
    					"?v=2&alt=json-in-script&callback=renderFeatured'><\/script>";
    $("body").append(script);
  }
}

/* Reveal a tab (playlist) box 
 * @param name  The name of the tab
 */
function showBox(name) {
  $("#"+name+"Box").addClass("selected").siblings().removeClass("selected");
  $("#"+name+"Tab").addClass("selected").siblings().removeClass("selected");
  return false;
}

/* Highlight a video thumbnail, including all duplicates that there may be 
 * @param link  The link <a> object that was clicked
 */
function setSelected(link) {
  var videoId = $(link).attr("class");
  if (videoId.indexOf("selected") != -1) {  // this means this video is already selected and playing, so bail out
    return false;
  }
  $(".videoPreviews .selected").removeClass("selected");
  $("a." + videoId).addClass("selected").each( function (i) {
  	 if ($(this).is(":hidden")) {
  	   var boxName = $(this).parent().parent().parent().attr("id").split("Box");
  	   $("#"+boxName[0]+"Tab a").click();
  	 }
  });
  return false;
}

/* Reveal and hide the long/short descriptions for a video in the playlist 
 * @param link  The link <a> object that was clicked 
 */
function toggleDescription(link) {
	var aToggle = $(link);
	$("span", aToggle).toggle();
	var aDescription = $(">a", aToggle.parent().parent());
	$("p.short", aDescription).toggle();
	$("p.full", aDescription).toggle();
	if ($("span.less", aToggle).is(":visible")) {
		aDescription.css("height", "auto");
	} else {
		aDescription.css("height", "90px");
	}
	return false;
}

/* Add actions to the page onload event so that we load a video right away */
addLoadEvent(function () {
  // if there's a video url in the hash, click that video
  if (location.href.indexOf("#v=") != -1) {
    var videoId = location.href.split("#v=");
    clickVideo(videoId[1]);
  } else { // otherwise, click the default video
    clickDefaultVideo();
  }
});


var clickVideoAttempts = 0; // Used with clickVideo()

/* Click a video in order to load it and select it 
 * @param videoId  The ID of the video to click
 */
function clickVideo(videoId) {
  if ($("." + videoId).length != 0) {  // if we find the video, click it and return
   $("." + videoId).addClass("noplay"); // add class to indicate we should NOT autoplay (class removed by loadVideo)
  	$("." + videoId + ":first").click();
	 return;
  } else { // if we don't find it, increment clickVideoAttempts
	 console.log("video NOT found: " + videoId);
	 clickVideoAttempts++;
  }
    
  // if we don't find it after 20 attempts (2 seconds), click the first feature video
  if (clickVideoAttempts > 10) {
	 console.log("video never found, clicking default...");
    clickVideoAttempts = 0;
    clickDefaultVideo();
  } else { // try again after 100 milliseconds
	 setTimeout('clickVideo("'+videoId+'")', 100);
  }
}

/* Click the default video that should be loaded on page load (the first video in the featured list) */
function clickDefaultVideo() {
	if ($("#mainBodyRight .videoPreviews a:first").length != 0) {
  	var videoId = $("#mainBodyRight .videoPreviews a:first").attr("class");
    $("." + videoId).addClass("noplay"); // add class to indicate we should NOT autoplay (class removed by loadVideo)
  	$("." + videoId + ":first").click();
  	return;
  } else { // if we don't find it, increment clickVideoAttempts
	 console.log("default video NOT found");
	 clickVideoAttempts++;
  }
  
  // if we don't find it after 50 attempts (5 seconds), just fail
  if (clickVideoAttempts > 50) {
	  console.log("default video never found...");
  } else { // try again after 100 milliseconds
	 	setTimeout('clickDefaultVideo()', 100);
  }
}
</script>

  <div id="mainBodyFixed">
	
    <div id="mainBodyLeft" class="videoPlayer" >	
      <div id="videoPlayerBox">
        <div id="videoBorder">
          <div id="videoPlayerTitle"></div>
          <div id="objectWrapper">
            <object id="player"></object>
          </div>
        </div>
      </div>
    </div><!-- end mainBodyLeft -->
    
    <div id="mainBodyRight" class="videoPlayer">
      <h2>Featured Videos</h2>
      <ul class="videoPreviews"></ul>
    </div><!-- end mainBodyRight -->
	  
    <ul id="videoTabs">
      <li id="aboutTab" class="selected"><a onclick="return showBox('about');" href="#">About the Platform</a></li>
      <li id="developertipsTab"><a onclick="return showBox('developertips');" href="#">Developer Tips</a></li>
      <li id="googleioTab"><a onclick="return showBox('googleio');" href="#">Google I/O Sessions</a></li>
      <li id="developersandboxTab"><a onclick="return showBox('developersandbox');" href="#">Developer Sandbox</a></li>
    </ul>
  	
    <div id="videos">
      <div id="aboutBox" class="selected"></div>
      <div id="developertipsBox"></div>
      <div id="googleioBox"></div>
      <div id="developersandboxBox"></div>
    </div>
    
  </div><!-- end mainBodyFixed -->
  
<script type="text/javascript">
// Initialization actions
showFeatured();            // load featured videos
showPlaylists();           // load playlists
</script>