console.log('[Oasis Mobile] Node.js backend starting...');

process.env.HOME = process.env.HOME || require('path').resolve(__dirname, '..', '..');
process.env.ssb_appname = process.env.ssb_appname || 'ssb';
process.env.OASIS_MOBILE = '1';
process.env.CHLORIDE_JS = '1';

const path = require('path');
const fs = require('fs');

try {
    const androidInfo = JSON.parse(fs.readFileSync(path.join(__dirname, '.android.json'), 'utf8'));
    if (androidInfo.versionName) process.env.OASIS_ANDROID_VERSION = String(androidInfo.versionName);
    if (androidInfo.versionCode) process.env.OASIS_ANDROID_VERSION_CODE = String(androidInfo.versionCode);
    process.env.OASIS_ANDROID_INSTALLER = String(androidInfo.installer || '');
} catch (e) {}

const tmpDir = path.join(process.env.HOME, 'tmp');
try { fs.mkdirSync(tmpDir, { recursive: true }); } catch (e) {}
process.env.TMPDIR = tmpDir;
process.env.TMP = tmpDir;
process.env.TEMP = tmpDir;
try { require('os').tmpdir = () => tmpDir; } catch (e) {}

try {
    const dns = require('dns');
    const net = require('net');
    const servers = ['8.8.8.8', '1.1.1.1', '8.8.4.4'];
    const systemLookup = dns.lookup;
    const SYSTEM_LOOKUP_MS = 5000;
    try { dns.setServers(servers); } catch (e) {}
    try { if (dns.promises && dns.promises.setServers) dns.promises.setServers(servers); } catch (e) {}

    const localResolve = (hostname, family) => {
        if (hostname === 'localhost' || hostname === 'localhost.localdomain' || hostname === 'ip6-localhost') {
            return family === 6 ? { address: '::1', family: 6 } : { address: '127.0.0.1', family: 4 };
        }
        const ipv = net.isIP(hostname);
        if (ipv) return { address: hostname, family: ipv };
        return null;
    };

    const safeLookup = function (hostname, options, callback) {
        if (typeof options === 'function') { callback = options; options = {}; }
        options = options || {};
        const family = options.family === 6 ? 6 : 4;
        const direct = localResolve(hostname, family);
        if (direct) {
            return process.nextTick(() => options.all
                ? callback(null, [direct])
                : callback(null, direct.address, direct.family));
        }
        // rama movil: primero el resolutor del sistema (getaddrinfo), que es el que
        // respeta la VPN y el DNS privado de Android. Upstream iba siempre a
        // 8.8.8.8/1.1.1.1, y las VPN que evitan fugas de DNS (Mullvad, por ejemplo)
        // o las redes que bloquean DNS externos los rechazan: no se encontraba
        // ningun pub por nombre y unirse a uno "no hacia nada". Los publicos quedan
        // de respaldo, para los moviles donde getaddrinfo no contesta.
        // Los dos caminos compiten: el del sistema sale ya y, si en SYSTEM_LOOKUP_MS
        // no ha contestado o falla, se pregunta tambien a los publicos. Gana la primera
        // respuesta buena; si fallan los dos, se devuelve el error del sistema, que
        // dice mas ("no existe") que el de unos servidores quiza bloqueados.
        let done = false, sysErr = null, pubErr = null, sysDone = false, pubDone = false, pubStarted = false;
        const finish = (err, address, fam) => {
            if (done) return;
            done = true;
            clearTimeout(timer);
            if (err) return callback(err);
            if (options.all) return callback(null, Array.isArray(address) ? address : [{ address, family: fam }]);
            if (Array.isArray(address)) return callback(null, address[0].address, address[0].family);
            return callback(null, address, fam);
        };
        const bothFailed = () => { if (sysDone && pubDone) finish(sysErr || pubErr || new Error('ENOTFOUND ' + hostname)); };
        const viaPublic = () => {
            if (pubStarted) return;
            pubStarted = true;
            const resolver = family === 6 ? dns.resolve6 : dns.resolve4;
            resolver.call(dns, hostname, (err, addrs) => {
                pubDone = true;
                if (err || !addrs || !addrs.length) { pubErr = err || new Error('ENOTFOUND ' + hostname); return bothFailed(); }
                finish(null, options.all ? addrs.map((x) => ({ address: x, family })) : addrs[0], family);
            });
        };
        const timer = setTimeout(viaPublic, SYSTEM_LOOKUP_MS);
        systemLookup.call(dns, hostname, { family, all: !!options.all }, (err, address, fam) => {
            sysDone = true;
            if (!err) return finish(null, address, fam);
            sysErr = err;
            if (pubStarted) bothFailed(); else viaPublic();
        });
    };

    dns.lookup = safeLookup;
    if (dns.promises) {
        dns.promises.lookup = (hostname, options) => new Promise((resolve, reject) => {
            safeLookup(hostname, options || {}, (err, address, family) => {
                if (err) return reject(err);
                if (options && options.all) return resolve(address);
                resolve({ address, family });
            });
        });
    }
} catch (e) {}

const backendPath = path.join(__dirname, 'src', 'backend', 'backend.js');

console.log('[Oasis] Launching Oasis Social Network Utopia...');
console.log('[Oasis] Backend path:', backendPath);
console.log('[Oasis] HOME:', process.env.HOME);

try {
    require(backendPath);
    console.log('[Oasis] Backend started on port 3000');
} catch (error) {
    console.error('[Oasis] Error starting backend:', error);
}