Solution to level 13 in Untrusted: http://alex.nisnevich.com/untrusted/

untrusted-lvl13-solution.js

/*
 * robotMaze.js
 *
 * The blue key is inside a labyrinth, and extracting
 * it will not be easy.
 *
 * It's a good thing that you're a AI expert, or
 * we would have to leave empty-handed.
 */

function startLevel(map) {
    // Hint: you can press R or 5 to "rest" and not move the
    // player, while the robot moves around.

    map.getRandomInt = function(min, max) {
        return Math.floor(Math.random() * (max - min + 1)) + min;
    }

    map.placePlayer(map.getWidth()-1, map.getHeight()-1);
    var player = map.getPlayer();

    map.defineObject('robot', {
        'type': 'dynamic',
        'symbol': 'R',
        'color': 'gray',
        'onCollision': function (player, me) {
            me.giveItemTo(player, 'blueKey');
        },
        'behavior': function (me) {
            var player = map.getPlayer();
            
            const DPAD_X = 20;
            const DPAD_Y = 16;
            
            function markDpadOffset(xOffset,yOffset) {
                map.setSquareColor(
                    DPAD_X + xOffset,
                    DPAD_Y + yOffset,
                    'blue'
                );
            }
            markDpadOffset(0,0);
            markDpadOffset(-1,0);
            markDpadOffset(1,0);
            markDpadOffset(0,-1);
            markDpadOffset(0,1);
            
            function playerAtDpadOffset(xOffset, yOffset) {
                return playerX == DPAD_X + xOffset
                    && playerY == DPAD_Y + yOffset;
            }
            var playerX = player.getX();
            var playerY = player.getY();
            var dir = '';
            if (playerAtDpadOffset(0,1)) {
                dir = 'down';
            } else if (playerAtDpadOffset(0,-1)) {
                dir = 'up';
            } else if (playerAtDpadOffset(1,0)) {
                dir = 'right';
            } else if (playerAtDpadOffset(-1,0)) {
                dir = 'left';
            }
            
            if (me.canMove(dir)) me.move(dir);











































        }
    });

    map.defineObject('barrier', {
        'symbol': '░',
        'color': 'purple',
        'impassable': true,
        'passableFor': ['robot']
    });

    map.placeObject(0, map.getHeight() - 1, 'exit');
    map.placeObject(1, 1, 'robot');
    map.placeObject(map.getWidth() - 2, 8, 'blueKey');
    map.placeObject(map.getWidth() - 2, 9, 'barrier');

    var autoGeneratedMaze = new ROT.Map.DividedMaze(map.getWidth(), 10);
    autoGeneratedMaze.create( function (x, y, mapValue) {
        // don't write maze over robot or barrier
        if ((x == 1 && y == 1) || (x == map.getWidth() - 2 && y >= 8)) {
            return 0;
        } else if (mapValue === 1) { //0 is empty space 1 is wall
            map.placeObject(x,y, 'block');
        } else {
            map.placeObject(x,y,'empty');
        }
    });
}

function validateLevel(map) {
    map.validateExactlyXManyObjects(1, 'exit');
    map.validateExactlyXManyObjects(1, 'robot');
    map.validateAtMostXObjects(1, 'blueKey');
}

function onExit(map) {
    if (!map.getPlayer().hasItem('blueKey')) {
        map.writeStatus("We need to get that key!");
        return false;
    } else {
        return true;
    }
}