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 var scheduler = exports;

 //

 // ### function Scheduler (connection)

 // #### @connection {spdy.Connection} active connection

 // Connection's streams scheduler

 //

 function Scheduler(connection) {

   this.connection = connection;

   this.priorities = [[], [], [], [], [], [], [], []];

   this._tickListener = null;

 }

 //

 // ### function create (connection)

 // #### @connection {spdy.Connection} active connection

 //

 exports.create = function create(connection) {

   return new Scheduler(connection);

 };

 //

 // ### function schedule (stream, data)

 // #### @stream {spdy.Stream} Source stream

 // #### @data {Buffer} data to write on tick

 // Use stream priority to invoke callbacks in right order

 //

 Scheduler.prototype.schedule = function schedule(stream, data) {

   this.priorities[stream.priority].push(data);

 };

 //

 // ### function tick ()

 // Add .nextTick callback if not already present

 //

 Scheduler.prototype.tick = function tick() {

   if (this._tickListener !== null) return;

   var self = this;

   this._tickListener = function() {

     var priorities = self.priorities;

     self._tickListener = null;

     self.priorities = [[], [], [], [], [], [], [], []];

     // Run all priorities

     for (var i = 0; i < 8; i++) {

       for (var j = 0; j < priorities[i].length; j++) {

         self.connection.write(

           priorities[i][j]

         );

       }

     }

   };

   if (this.connection.parser.drained) {

     process.nextTick(this._tickListener);

   } else {

     this.connection.parser.once('drain', this._tickListener);

   }

 };