Files
edx-platform/courseware/static/js/video_player.js
2011-12-26 18:27:39 -05:00

317 lines
7.3 KiB
JavaScript

// Things to abstract out to another file
function postJSON(url, data, callback, csrf) {
$.ajax({
url: url,
dataType: 'json',
data: data,
success: callback
});
}
var global=5;
// Video player
var load_id = 0;
var video_speed = 1.0;
function change_video_speed(speed, youtube_id) {
new_position = ytplayer.getCurrentTime() * video_speed / speed;
video_speed = speed;
ytplayer.loadVideoById(youtube_id, new_position);
}
function caption_at(index) {
if (captions==0)
return " ";
text_array=captions.text
if ((index>=text_array.length) || (index < 0))
return "&nbsp;";
return text_array[index];
}
function caption_time_at(index) {
if (captions==0)
return 0;
time_array=captions.start;
if (index < 0)
return 0;
if (index>=time_array.length)
return ytplayer.getDuration();
return time_array[index] / 1000.0 / video_speed;
}
function caption_index(now) {
// Returns the index of the current caption, given a time
now = now * video_speed;
if (captions==0)
return 0;
time_array=captions.start
// TODO: Bisection would be better, or something incremental
var i;
for(i=0;i<captions.start.length; i++) {
if(time_array[i]>(now*1000)) {
return i-1;
}
}
return i-1;
}
function update_captions(t) {
var i=caption_index(t);
$("#std_n5").html(caption_at(i-5));
$("#std_n4").html(caption_at(i-4));
$("#std_n3").html(caption_at(i-3));
$("#std_n2").html(caption_at(i-2));
$("#std_n1").html(caption_at(i-1));
$("#std_0").html(caption_at(i));
$("#std_p1").html(caption_at(i+1));
$("#std_p2").html(caption_at(i+2));
$("#std_p3").html(caption_at(i+3));
$("#std_p4").html(caption_at(i+4));
$("#std_p5").html(caption_at(i+5));
$("#std_p6").html(caption_at(i+6));
}
function title_seek(i) {
// Seek video forwards or backwards by i subtitles
current=caption_index(getCurrentTime());
new_time=caption_time_at(current+i);
ytplayer.seekTo(new_time, true);
}
function updateHTML(elmId, value) {
document.getElementById(elmId).innerHTML = value;
}
function setytplayerState(newState) {
// updateHTML("playerstate", newState);
}
// Updates server with location in video so we can resume from the same place
// IMPORTANT TODO: Load test
// POSSIBLE FIX: Move to unload() event and similar
var ajax_video=function(){};
function onYouTubePlayerReady(playerId) {
ytplayer = document.getElementById("myytplayer");
setInterval(updateytplayerInfo, 1000);
setInterval(ajax_video,1000);
ytplayer.addEventListener("onStateChange", "onytplayerStateChange");
ytplayer.addEventListener("onError", "onPlayerError");
if((typeof load_id != "undefined") && (load_id != 0)) {
var id=load_id;
loadNewVideo(id, 0);
}
}
function videoDestroy() {
load_id = 0;
// TODO/BUG: Figure out why removeEventListener doesn't work
ytplayer.removeEventListener("onStateChange", "onytplayerStateChange");
ytplayer.removeEventListener("onError", "onPlayerError");
ytplayer = false;
}
function log_event(e, d) {
// CRITICAL TODO: Change to AJAX
//$("#eventlog").append("<br>");
//$("#eventlog").append(JSON.stringify(e));
// TODO: Figure out
// XMLHttpRequest cannot load http://localhost:7000/userlog. Origin http://localhost:8000 is not allowed by Access-Control-Allow-Origin.
/*window['console'].log(JSON.stringify(e));
$.get("http://localhost:7000/userlog",
{'user':'pmitros',
'key':'key',
'event_type':'unknown',
'data':'e'},
function(data) {
});*/
}
function seek_slide(type,oe,value) {
//log_event('video', [type, value]);
if(type=='slide') {
// HACK/TODO: Youtube recommends this be false for slide and true for stop.
// Works better on my system with true/true.
// We should test both configurations on low/high bandwidth
// connections, and different browsers
// One issue is that we query the Youtube window every 250ms for position/state
// With false, it returns the old one (ignoring the new seek), and moves the
// scroll bar to the wrong spot.
ytplayer.seekTo(value, true);
} else if (type=='stop') {
ytplayer.seekTo(value, true);
log_event('video', [type, value]);
}
update_captions(value);
}
function get_state() {
if (ytplayer)
return [ytplayer.getPlayerState(),
ytplayer.getVideoUrl(),
ytplayer.getDuration(), ytplayer.getCurrentTime(),
ytplayer.getVideoBytesLoaded(), ytplayer.getVideoBytesTotal(),
ytplayer.getVideoStartBytes(),
ytplayer.getVolume(),ytplayer.isMuted(),
ytplayer.getPlaybackQuality(),
ytplayer.getAvailableQualityLevels()];
return [];
}
function onytplayerStateChange(newState) {
setytplayerState(newState);
log_event('video', ['State Change',newState, get_state()]);
}
function onPlayerError(errorCode) {
alert("An error occured: " + errorCode);
}
function updateytplayerInfo() {
if(ytplayer.getPlayerState()!=3) {
$("#slider").slider("option","max",ytplayer.getDuration());
$("#slider").slider("option","value",ytplayer.getCurrentTime());
}
if (getPlayerState() == 1){
update_captions(getCurrentTime());
}
// updateHTML("videoduration", getDuration());
// updateHTML("videotime", getCurrentTime());
// updateHTML("startbytes", getStartBytes());
// updateHTML("volume", getVolume());
}
// functions for the api calls
function loadNewVideo(id, startSeconds) {
captions={"start":[0],"end":[0],"text":["Attempting to load captions..."]};
$.getJSON("/static/subs/"+id+".srt.sjson", function(data) {
captions=data;
});
load_id = id;
//if ((typeof ytplayer != "undefined") && (ytplayer.type=="application/x-shockwave-flash")) {
// Try it every time. If we fail, we want the error message for now.
// TODO: Add try/catch
try {
ytplayer.loadVideoById(id, parseInt(startSeconds));
load_id=0;
}
catch(e) {
window['console'].log(JSON.stringify(e));
}
}
function cueNewVideo(id, startSeconds) {
if (ytplayer) {
ytplayer.cueVideoById(id, startSeconds);
}
}
function play() {
if (ytplayer) {
ytplayer.playVideo();
}
}
function pause() {
if (ytplayer) {
ytplayer.pauseVideo();
}
}
function stop() {
if (ytplayer) {
ytplayer.stopVideo();
}
}
function getPlayerState() {
if (ytplayer) {
return ytplayer.getPlayerState();
}
}
function seekTo(seconds) {
if (ytplayer) {
ytplayer.seekTo(seconds, true);
}
}
function getBytesTotal() {
if (ytplayer) {
return ytplayer.getVideoBytesTotal();
}
}
function getCurrentTime() {
if (ytplayer) {
return ytplayer.getCurrentTime();
}
}
function getDuration() {
if (ytplayer) {
return ytplayer.getDuration();
}
}
function getStartBytes() {
if (ytplayer) {
return ytplayer.getVideoStartBytes();
}
}
function mute() {
if (ytplayer) {
ytplayer.mute();
}
}
function unMute() {
if (ytplayer) {
ytplayer.unMute();
}
}
function getEmbedCode() {
alert(ytplayer.getVideoEmbedCode());
}
function getVideoUrl() {
alert(ytplayer.getVideoUrl());
}
function setVolume(newVolume) {
if (ytplayer) {
ytplayer.setVolume(newVolume);
}
}
function getVolume() {
if (ytplayer) {
return ytplayer.getVolume();
}
}
function clearVideo() {
if (ytplayer) {
ytplayer.clearVideo();
}
}