http://honeypot.softwareskills.se level 2

solution

var api = require('./API.js');
var route = ['r','','l','f','f','f','f','','','','f','f','f','f','f'],
    move = '',
    env = [],
    lastEnv = [];

function next() {
    move = route.shift();
}

function followWall(decision) {
    if (lastEnv[1] == 1 && env[1] > 1) decision = 'r';
    else if (lastEnv[3] == 1 && env[3] > 1) decision = 'l';
    console.log('followWall: ' + decision);
    return decision;
}

function avoidObstacle(decision) {
    if (env[0] < 2) {
        // block ahead
        if (env[1] > 1) decision = 'r';
        else if (env[3] > 1) decision = 'l';
        else decision = 'b';
    }
    console.log('avoid: ' + decision);
    return decision;
}

next();
 
exports.update = function() {
    if (api.identifyTarget()) {
        api.fireCannon();
    } else {
        env = [api.lidarFront(),api.lidarRight(),api.lidarBack(),api.lidarLeft()];
        var decision = move;
        
        decision = avoidObstacle(decision);
        if (move == 'f') decision = followWall(decision);
        switch (decision) {
            case 'r':
                api.turnRight();
                next();
                break;
            case 'l':
                api.turnLeft();
                next();
                break;
            case 'b':
                api.moveBackward();
                route.unshift('b');
                break;
            default:
                api.moveForward();
        }
        
        lastEnv = env.slice();
    }
};

rev 1: 1251