Video.js - Pastebin for Sharing Code and Text

// files to load, recursive object, associates files with keys
    this.deps = options.deps || {};
    
    // function to call before another video starts
    this._teardown = options.teardown || function() {};

// function to call when this video starts
    this._start = options.start || function(container, callback) { callback() };

// function to call when the position is changed
    this._setPosition = options.setPosition || function() {};

this._loop = options.loop;

this._resize = options.resize;

this._canPlay = options.canPlay || function () { return true };

_.extend(this, options.methods || {});

// should we smooth the playhead
    this.smoothPosition = true;

// maximum amount to let the smoothed playhead drift from the actual playhead
    this.maxSmooth = 300;

// global millisecond offset for midi player
    this.offset = options.offset;

this.lastPosition = this.position = 0;
    this.started = false;

}

Video.prototype.start = function(container, forcePlayback, success, failure) {

if (!forcePlayback) {
        var canPlay = this._canPlay();

if (canPlay !== true) {
            failure(canPlay);
            return;
        }
    }

var _this = this;

var count = 0;
    count += this.player ? 0 : 1;
    count += countStrings(this.deps);

var loaded = _.after(count, function() {

_this.depsLoaded = true;
        
        if (_this._resize) window.removeEventListener('resize', this._resize, false);
        start();

});

container.className = this.slug;

// if we haven't made a player object for this track yet ...
    if (!this.player) {
        this.player = new midi.Player('mid/'+this.slug+'.mid');
        this.player.load(loaded);
    }

// load deps
    if (this.depsLoaded) {

start();

} else {

_.each(this.deps, function(paths, dict) {

this.deps[dict] = {};

_.each(paths, function(path, key) {
                get(path, function(text) {
                    _this.deps[dict][key] = text;
                    loaded();
                });
            });   
        
        }, this);

}

function start() {
        _this._start(container, function() {
            _this.started = true;
            success();
        });
    }

// count keys in 1 level deep object    
    function countStrings(obj) {
        var count = 0;
        _.each(obj, function(dict, key) {
            count += _.keys(dict).length;
        });
        return count;
    }

};

Video.prototype.update = function(sourcePosition) {

sourcePosition = sourcePosition || 0;

this.lastTime = this.time;
    this.time = Date.now();

if (sourcePosition != this.lastPosition) {
        this.position = sourcePosition;
    } else if (this.smoothPosition) { 
        this.position += (this.time - this.lastTime);
        this.position = Math.min(this.position, sourcePosition + this.maxSmooth);
    }

this.lastPosition = sourcePosition;

this.player.update(this.position - this.offset);

};

// gives videos access to the main raf loop.
Video.prototype.loop = function() {
    this.started && this._loop && this._loop(this.position, this.lastPosition);
};

Video.prototype.setPosition = function(position) {
    this._loop && this.loop(position, this.lastPosition);
    this._setPosition(position, this.lastPosition);
    this.lastTime = this.time = Date.now();
    this.player.setPosition(position);
};

Video.prototype.play = function() {
    this.lastTime = this.time = Date.now();
    if (this.player) this.player.play();
};

Video.prototype.pause = function() {
    if (this.player) this.player.pause();
};

Video.prototype.teardown = function(container) {
    // todo: reset clock?
    this.lastPosition = this.position = 0;
    this.pause();
    this._teardown(container);
    this.started = false;
    if (this._resize) window.removeEventListener('resize', this._resize, false);
}