michael@0: var scheduler = exports;
michael@0: 
michael@0: //
michael@0: // ### function Scheduler (connection)
michael@0: // #### @connection {spdy.Connection} active connection
michael@0: // Connection's streams scheduler
michael@0: //
michael@0: function Scheduler(connection) {
michael@0:   this.connection = connection;
michael@0:   this.priorities = [[], [], [], [], [], [], [], []];
michael@0:   this._tickListener = null;
michael@0: }
michael@0: 
michael@0: //
michael@0: // ### function create (connection)
michael@0: // #### @connection {spdy.Connection} active connection
michael@0: //
michael@0: exports.create = function create(connection) {
michael@0:   return new Scheduler(connection);
michael@0: };
michael@0: 
michael@0: //
michael@0: // ### function schedule (stream, data)
michael@0: // #### @stream {spdy.Stream} Source stream
michael@0: // #### @data {Buffer} data to write on tick
michael@0: // Use stream priority to invoke callbacks in right order
michael@0: //
michael@0: Scheduler.prototype.schedule = function schedule(stream, data) {
michael@0:   this.priorities[stream.priority].push(data);
michael@0: };
michael@0: 
michael@0: //
michael@0: // ### function tick ()
michael@0: // Add .nextTick callback if not already present
michael@0: //
michael@0: Scheduler.prototype.tick = function tick() {
michael@0:   if (this._tickListener !== null) return;
michael@0:   var self = this;
michael@0:   this._tickListener = function() {
michael@0:     var priorities = self.priorities;
michael@0: 
michael@0:     self._tickListener = null;
michael@0:     self.priorities = [[], [], [], [], [], [], [], []];
michael@0: 
michael@0:     // Run all priorities
michael@0:     for (var i = 0; i < 8; i++) {
michael@0:       for (var j = 0; j < priorities[i].length; j++) {
michael@0:         self.connection.write(
michael@0:           priorities[i][j]
michael@0:         );
michael@0:       }
michael@0:     }
michael@0:   };
michael@0: 
michael@0:   if (this.connection.parser.drained) {
michael@0:     process.nextTick(this._tickListener);
michael@0:   } else {
michael@0:     this.connection.parser.once('drain', this._tickListener);
michael@0:   }
michael@0: };