elevator.js

{
    init: function(elevators, floors) {
        const DIR_NONE = 0x0;
        const DIR_UP = 0x1;
        const DIR_DOWN = 0x2;
        
        let floorCount = floors.length;
        let upRequests = initArray(floorCount);
        let downRequests = initArray(floorCount);

        for (var elevator of elevators) {
            initElevator(elevator);
        }
        for (var floor of floors) {
            initFloor(floor);
        }

        function initElevator(elevator) {
            elevator.requests = initArray(floorCount);
            
            elevator.setDirection = function(direction) {
                let goingUp = direction & DIR_UP;
                let goingDown = direction & DIR_DOWN;
                elevator.goingUpIndicator(goingUp);
                elevator.goingDownIndicator(goingDown);
            }
            
            elevator.handleRequest = function(floorNum, direction) {
                if (elevator.destinationDirection() == "stopped") {
                    elevator.setDirection(direction);
                    elevator.goToFloor(floorNum);
                }
            }

            // Whenever the elevator is idle (has no more queued destinations) ...
            elevator.on("idle", function() {
                elevator.setDirection(DIR_NONE);
            });

            elevator.on("floor_button_pressed", function(floorNum) {
                elevator.requests[floorNum] = true;
                let direction = floorNum - elevator.currentFloor() > 0 ? DIR_UP : DIR_DOWN;
                elevator.handleRequest(floorNum, direction);
            });

            elevator.on("passing_floor", function(floorNum, direction) {
                let externalRequests = direction == "up" ? upRequests : downRequests;
                if (externalRequests[floorNum] && elevator.loadFactor() < 0.95) {
                    elevator.goToFloor(floorNum, true);
                }
            });

            elevator.on("stopped_at_floor", function(floorNum) {
                elevator.requests[floorNum] = false;
                upRequests[floorNum] = false;
                downRequests[floorNum] = false;
            });
        }

        function initFloor(floor) {
            let floorNum = floor.floorNum();
            floor.on("up_button_pressed", function() {
                upRequests[floorNum] = true;
                getElevator(floorNum, DIR_UP).handleRequest(floorNum, DIR_UP);
            });

            floor.on("down_button_pressed", function() {
                downRequests[floorNum] = true;
                getElevator(floorNum, DIR_DOWN).handleRequest(floorNum, DIR_DOWN);
            });
        }
        
        function getElevator(floorNum, direction) {
            return elevators[0];
        }

        function initArray(size) {
            return new Array(size).fill(false);
        }
    },
        update: function(dt, elevators, floors) {
            // We normally don't need to do anything here
        }
}