jasmine.Queue = function(env) {
  this.env = env;

  // parallel to blocks. each true value in this array means the block will
  // get executed even if we abort
  this.ensured = [];
  this.blocks = [];
  this.running = false;
  this.index = 0;
  this.offset = 0;
  this.abort = false;
};

jasmine.Queue.prototype.addBefore = function(block, ensure) {
  if (ensure === this.env.undefined) {
    ensure = false;
  }

  this.blocks.unshift(block);
  this.ensured.unshift(ensure);
};

jasmine.Queue.prototype.add = function(block, ensure) {
  if (ensure === this.env.undefined) {
    ensure = false;
  }

  this.blocks.push(block);
  this.ensured.push(ensure);
};

jasmine.Queue.prototype.insertNext = function(block, ensure) {
  if (ensure === this.env.undefined) {
    ensure = false;
  }

  this.ensured.splice((this.index + this.offset + 1), 0, ensure);
  this.blocks.splice((this.index + this.offset + 1), 0, block);
  this.offset++;
};

jasmine.Queue.prototype.start = function(onComplete) {
  this.running = true;
  this.onComplete = onComplete;
  this.next_();
};

jasmine.Queue.prototype.isRunning = function() {
  return this.running;
};

jasmine.Queue.LOOP_DONT_RECURSE = true;

jasmine.Queue.prototype.incrementQueue = function() {
  if (this.blocks[this.index].abort) {
    this.abort = true;
  }
  this.offset = 0;
  this.index++;
  this.next_();
}

jasmine.Queue.prototype.next_ = function() {
  var self = this;
  // var goAgain = true;

  // while (goAgain) {
    // goAgain = false;

    if (self.index < self.blocks.length && !(this.abort && !this.ensured[self.index])) {
      // var calledSynchronously = true;
      // var completedSynchronously = false;

      // var onComplete = function () {
        // if (jasmine.Queue.LOOP_DONT_RECURSE && calledSynchronously) {
          // completedSynchronously = true;
          // return;
        // }

        self.blocks[self.index].execute(function() { self.incrementQueue() });


        // var now = new Date().getTime();
        // if (self.env.updateInterval && now - self.env.lastUpdate > self.env.updateInterval) {
          // self.env.lastUpdate = now;
          // self.env.setTimeout(function() {
            // self.next_();
          // }, 0);
        // } else {
          // if (jasmine.Queue.LOOP_DONT_RECURSE && completedSynchronously) {
            // goAgain = true;
          // } else {
            // self.next_();
          // }
        // }
      // };
      // self.blocks[self.index].execute(function() { self.next_(); });

      // calledSynchronously = false;
      // if (completedSynchronously) {
        // onComplete();
      // }

    } else {
      self.running = false;
      if (self.onComplete) {
        self.onComplete();
      }
    }
  // }
};