ElevatorSaga try

elevator.js

{
    init: function(elevators, floors) {

        document.elevators = elevators;

        document.way = function() {
            c = this.currentFloor();
            if (this.destinationQueue.length === 0) {
                return null;
            }
            d = this.destinationQueue[0];
            if (c == d) {
                return 0;
            }
            if (c > d) {
                return -1;
            } else {
                return 1;
            }
        }

        document.opposite = function(e, i, a) { return -e; }

        document.score = function(elevator, floor, wanted_way) {
            elev_way = elevator.way();

            if (elev_way > 0) {
                fq = elevator.destinationQueue;
                ff = floor;
                fc = elevator.currentFloor();
            } else {
                fq = elevator.destinationQueue.map(document.opposite);
                ff = -floor;
                fc = -elevator.currentFloor();
            }

            if (wanted_way > 0) {
                if (ff > fc) {
                    loc = 'head';
                } else {
                    loc = 'tail';
                }
            } else {
                loc = 'intermediate';
            }

            offset = 0;
            elev_score = 0;

            // head
            [idx, elev_score] = document.head_score(fc, fq, ff, elev_score, loc != 'head');

            if (loc === 'head') {
                return [idx, elev_score, loc];
            }

            // intermediate
            fq = fq.slice(idx).map(document.opposite);
            ff = -ff;
            [idx, elev_score] = document.head_score(fq[0], fq, ff, elev_score, loc != 'intermediate');

            if (loc === 'intermediate') {
                return [idx, elev_score, loc];
            }

            // tail
            fq = fq.slice(idx).map(document.opposite);
            ff = -ff;
            [idx, elev_score] = document.head_score(fq[0], fq, ff, elev_score, false);
            return [idx, elev_score, loc];
        }

        document.head_score = function(current, queue, floor, h_score, skip) {
            idx = 0;
            l = queue.length;
            cost = h_score + floor - current;
            if (l === 0) return [-1, cost];

            while ((idx < l-1) || (queue[idx] < queue[idx+1])) {
                if (!skip) {
                    if (floor === queue[idx]) { return [-2, cost]; }
                    if (floor > queue[idx] && floor < queue[idx+1]) { return [idx+1, cost]; }
                }
                idx++;
            }
            if (!skip) {
                if (floor === queue[idx]) { return [-2, cost]; }
                return [idx+1, cost];
            }
            return [idx, h_score+idx-current];
        }

        document.call_elevator = function(floor, wanted_way) {
            min_score = 9999999;
            min_elevator = document.elevators[0];
            min_idx = -3;
            document.elevators.forEach(function(e, i, a) {
                [idx, score, loc] = document.score(e, floor, wanted_way);
                if (score < min_score) {
                    min_score = score;
                    min_elevator = e;
                    min_idx = idx;
                }
            });
            min_elevator.destinationQueue.splice(idx, 0, floor);
            min_elevator.checkDestinationQueue();
        }

        document.insert_head = function(elevator, floor) {
            idx = 0;
            queue = elevator.destinationQueue;
            l = queue.length;

            if (l === 0) {
                queue.push(floor);
                return;
            }

            elev_way = elevator.way();
            if (elev_way > 0) {
                queue = queue.map(document.opposite);
                ff = -floor;
            }

            while ((idx < l-1) || (queue[idx] < queue[idx+1])) {
                if (ff === queue[idx]) { return; }
                if (ff > queue[idx] && floor < queue[idx+1]) {
                    elevator.destinationQueue.splice(idx+1, 0, floor);
                    return;
                }
                idx++;
            }
            if (ff === queue[idx]) { return; }
            elevator.destinationQueue.splice(idx+1, 0, floor);
        }

        elevators.forEach(function(elevator, idx, array) {
            elevator.way = document.way;
            elevator.on('floor_button_pressed', function(floor) {
                console.log('pressed: '+floor);
                console.log(elevator.destinationQueue);
                document.insert_head(elevator, floor);
                console.log(elevator.destinationQueue);
                elevator.checkDestinationQueue();
            });

            elevator.on('stopped_at_floor', function(floor) {
                q = elevator.destinationQueue;
                if (elevator.goingUpIndicator()) {
                    if ((q.length > 0) && q[0] < elevator.currentFloor()) {
                        elevator.goingDownIndicator(true);
                    }
                }
                if (elevator.goingDownIndicator()) {
                    if ((q.length > 0) && q[0] > elevator.currentFloor()) {
                        elevator.goingUpIndicator(true);
                    }
                }
            });
        });

        floors.forEach(function(floor, idx, array) {
            floor.on("up_button_pressed", function() {
                console.log('called: '+floor.floorNum());
                console.log(elevators[0].destinationQueue);
                document.call_elevator(floor.floorNum(), 1);
                console.log(elevators[0].destinationQueue);
            });
            floor.on("down_button_pressed", function() {
                console.log('called: '+floor.floorNum());
                console.log(elevators[0].destinationQueue);
                document.call_elevator(floor.floorNum(), -1);
                console.log(elevators[0].destinationQueue);
            });
        });
    },
    update: function(dt, elevators, floors) {
    }
}