elevator-saga-solution

elevator.js

{
  elevators: null,
  floors: null,

  init: function(elevators, floors) {
    this.elevators = elevators;
    this.floors = floors;
    var self = this;

    elevators.forEach(function(v){
      v.on("idle", self.onIdle.bind(self, v));
      v.on("floor_button_pressed", self.onFloorButtonPress.bind(self, v));
      v.on("passing_floor", self.onPassingFloor.bind(self, v));
      v.on("stopped_at_floor", self.onStoppedAtFloor.bind(self, v));
      v.goingDownIndicator(false);
      v.goingUpIndicator(true);
    });

    floors.forEach(function(v){
      v.on("up_button_pressed", self.onUpButtonPress.bind(self, v));
      v.on("down_button_pressed", self.onDownButtonPress.bind(self, v));
    });
  },

  update: function(dt, elevators, floors) {},

  //
  // Elevator Events
  //

  onIdle: function(elevator) {
  },

  onFloorButtonPress: function(elevator, floorNum) {
    elevator.goToFloor(floorNum);
  },

  onPassingFloor: function(elevator, floorNum, direction) {
    num = elevator.destinationQueue.indexOf(floorNum);
    if (num >= 0 && elevator.loadFactor() < 0.8) {
      elevator.goToFloor(floorNum, true);
    }
  },

  onStoppedAtFloor: function(elevator, floorNum) {
    var q = elevator.destinationQueue.filter(function(v, k){
      return v !== floorNum;
    });
    elevator.destinationQueue = q;

    this.setIndicator(elevator);
  },

  //
  // Floor Events
  //

  onUpButtonPress: function(floor) {
    console.log('Up', floor.floorNum());
    var i, weight = [];

    for (i = 0; i < this.elevators.length; i++) {
      var elevator = this.elevators[i];
      weight[i] = this.getScore(floor.floorNum(), elevator, 'up');
    }

    this.addElevatorQueue(floor, weight);
  },

  onDownButtonPress: function(floor) {
    console.log('Down', floor.floorNum());
    var i, weight = [];

    for (i = 0; i < this.elevators.length; i++) {
      var elevator = this.elevators[i];
      weight[i] = this.getScore(floor.floorNum(), elevator, 'down');
    }

    this.addElevatorQueue(floor, weight);
  },

  //
  // Elevator Utils
  //

  getScore: function(floorNum, elevator, direction) {
    var current = elevator.currentFloor();

    if (elevator.destinationQueue.length === 0) {
      return this.floors.length + 1000 - Math.abs(current - floorNum);
    }

    var next = elevator.destinationQueue[0];

    if (current >= next && current >= floorNum && elevator.goingDownIndicator() && direction === 'down') {
      return current - next;
    } else if (current <= next && current <= floorNum && elevator.goingUpIndicator() && direction === 'up') {
      return next - current;
    }

    return 0;
  },

  addElevatorQueue: function(floor, weight) {
    console.log(weight);
    var re = weight.reduce(function(memo, v, i, array){
      if (memo.value < v) {
        return { index: i, value: v }
      }
      return memo;
    }, { index: 0, value: 0 });

    var elevator = this.elevators[re.index];
    elevator.goToFloor(floor.floorNum());

    this.setIndicator(elevator);
  },

  setIndicator: function(elevator) {
    if (elevator.destinationQueue.length === 0) {
      elevator.goingDownIndicator(true);
      elevator.goingUpIndicator(true);
      return
    }

    elevator.goingDownIndicator(false);
    elevator.goingUpIndicator(false);

    var next = elevator.destinationQueue[0];

    if (elevator.currentFloor() > next) {
      elevator.goingDownIndicator(true);
    } else {
      elevator.goingUpIndicator(true);
    }
  }
}