bfs.js

'use strict';

const Queue = require('./../libs/queue');

const def = (str)=> {
    return /^[wesndu]$/.test(str);
};

const raw = (start, goal, rooms, level, portals)=> {
    let que = new Queue();
    let visited = {};
    let path, num, exits, clone;

    for (let num in rooms) visited[num] = false;

    que.enqueue([[start]]);
    visited[start] = true;

    while ( ! que.isEmpty()) {
        path = que.dequeue();
        num = path[path.length - 1][0];
        exits = rooms[num].exits;

        if (num == goal) {
            let result = [[], []];

            for (let i = 0, len = path.length; i < len; i++) {
                result[0].push(path[i][0]);

                if (i != len - 1) result[1].push(path[i+1][1]);
            }

            return result;
        };

        if (num == start && portals) exits = exits.concat(portals);

        for (let i = exits.length - 1; i >= 0; i--) {
            let exit = exits[i];

            if ( ! visited[exit.dst] && rooms[exit.dst]) {
                visited[exit.dst] = true;
                
                clone = path.slice(0);
                clone.push([exit.dst, exit.cmd]);
                
                que.enqueue(clone);
            }
        }
    }

    return false;
};

const speedwalk = (raw)=> {
    let cnt = [];
    let mlt = 1;

    for (let i = 0, len = raw.length; i < len; i++) {
        let c = raw[i];
        let p = raw[i-1];
        let n = raw[i+1];

        if (def(c)) {
            if (! def(p)) cnt.push('');
            if (c == p) mlt++;

            if (c != n) {
                cnt[cnt.length - 1] += (mlt > 1 ? mlt : '') + c;
                mlt = 1;
            };

            if ( ! def(n)) cnt[cnt.length - 1] = 'run ' + cnt[cnt.length - 1];
        } else {
            cnt.push(c);
        }
    }

    return cnt;
};

const find = (start, goal, rooms, level, portals)=> {
    let [path, commands] = raw(start, goal, rooms, level, portals);

    return speedwalk(commands);
};

module.exports.raw = raw;
module.exports.speedwalk = speedwalk;
module.exports.find = find;