Elevator Saga Challenges 1-6

elevatorsaga

{
    init: function(elevators, floors) {
        var midPoint = Math.floor(floors.length / 2);
        var rotator = 0;
        
        _.each(floors, function(floor) {
            floor.on("up_button_pressed", function() {
                var destination = floor.floorNum();
                goToFloor(pickElevator(destination), destination, "press up");
            });

            floor.on("down_button_pressed", function() {
                var destination = floor.floorNum();
                goToFloor(pickElevator(destination), destination, "press down");
            });
        });
        
        _.each(elevators, function(elevator) {
            elevator.on("idle", function() {
                var increment = rotator++;
                var destination = 0;

                if (elevator.length > 1) {
                    destination = increment % 2 == 0 ? midPoint : increment % 3 == 0 ? floors.length - 1 : 0;
                }

                goToFloor(elevator, destination, "idle");
            });

            elevator.on("floor_button_pressed", function(floorNum) {
                goToFloor(elevator, floorNum, "press floor");
            });
        });

        function goToFloor(elevator, floorNum, logMessage) {
            var elevatorId = elevators.indexOf(elevator) + 1;

            console.log('this elevator 4', elevator);

            var currentFloor = elevator.currentFloor();
            var delta = getDelta(currentFloor, floorNum);
            var elevatorDelta = getElevatorDelta(elevator);

            console.log("Floor requested: ", floorNum);

            if (delta > 0 && !isGoingToFloor(floorNum)) {
                elevator.goToFloor(floorNum);

                prioritizeFloors(elevator);
                
                console.log(
                    ("Elevator " + elevatorId + " (floor " + currentFloor + ")"
                    + " going to floor: " + floorNum
                    + " (" + logMessage + ")").trim(), elevator.destinationQueue);
            }
            else {
                console.log ("Ignoring request (" + logMessage + ")", elevator.destinationQueue)
            }
        }
        
        function prioritizeFloors(elevator) {
            if (!elevator.destinationQueue) {
                return;
            }

            var currentFloor = elevator.currentFloor();
            var direction = getElevatorDirection(elevator);
            var firstHalf = [], secondHalf = [];
            
            firstHalf = elevator.destinationQueue.filter(function(floorNum) {
                return floorNum <= currentFloor;
            }).sort(); // down sequence

            secondHalf = elevator.destinationQueue.filter(function(floorNum) {
                return firstHalf.indexOf(floorNum) == -1;
            }).sort(); // up sequence
            
            if (direction == 'up') {
                firstHalf = firstHalf.reverse(); // up sequence
            }
            else {
                secondHalf = secondHalf.reverse(); // down sequen
            }

            elevator.destinationQueue = _.unique(firstHalf.concat(secondHalf));

            elevator.checkDestinationQueue();
        }

        function isGoingToFloor(elevator, floorNum) {
            return elevator.destinationQueue && elevator.destinationQueue.indexOf(floorNum) > -1;
        }

        function getDelta(start, end) {
            return Math.abs(start - end);
        }

        function getElevatorDelta(elevator) {
            return elevator.destinationQueue.length > 0 
                    ? getDelta(elevator.currentFloor(), elevator.getFirstPressedFloor()) 
                    : 0;
        }

        function getDirection(start, end) {
            return end ? (start < end ? "up" : "down") : "none";
        }

        function getElevatorDirection(elevator) {
            var destination = elevator.destinationQueue.length > 0 ? elevator.getFirstPressedFloor() : undefined;
            return getDirection(elevator.currentFloor(), destination);
        }

        function pickElevator(destination) {
            //elevators[rotator++ % elevators.length]
            //var sameDirection = _.groupBy(elevators, function(elevator) {
            //    return getElevatorDirection(elevator);
            //});
        
            var result;
            var idleElevators = elevators.filter(function(elevator) {
                return !elevator.destinationQueue || elevator.destinationQueue.length == 0;
            });

            if (idleElevators.length > 0) {
                return getClosestElevator(idleElevators, destination);
            }

            return getClosestElevator(elevators, destination);;
        }

        function getClosestElevator(availableElevators, destination) {
            var minDelta = floors.length;
            var result;

            availableElevators = availableElevators || elevators;

            _.each(availableElevators, function(elevator) {
                var elevatorDelta = getDelta(elevator.currentFloor(), destination);
                if ((minDelta = Math.min(elevatorDelta, minDelta)) == elevatorDelta) {
                    result = elevator;
                }
            });

            return result;
        }
    },
    update: function(dt, elevators, floors) {
    // We normally don't need to do anything here
    }
}