const fs = require("fs");
const path = require("path");
const url = require("url");
const util = require("util");
const Consensus = require("./tor/Consensus");
const OR = require("./tor/OnionRouter");
const Socket = require("./tor/Socket");
const { get } = require('./utils/http');

const LogLevels = {
  off: 0,
  error: 1,
  warn: 2,
  info: 3,
  debug: 4
}
let logLevel = LogLevels.error;
function timestamp() {
  const d = new Date().toISOString();
  return [d.substr(5, 5), d.substr(11, 8)].join(' ')
}

class Logger {
  debug(...args) {
    if (LogLevels.debug > logLevel) return;
    const [format, ...rest] = args;
    console.debug(timestamp(), "D", util.format(format, ...rest));
  }
  info(...args) {
    if (LogLevels.info > logLevel) return;
    const [format, ...rest] = args;
    console.debug(timestamp(), "I", util.format(format, ...rest));
  }
  warn(...args) {
    if (LogLevels.warn > logLevel) return;
    const [format, ...rest] = args;
    console.debug(timestamp(), "W", util.format(format, ...rest));
  }
  error(...args) {
    if (LogLevels.error > logLevel) return;
    const [format, ...rest] = args;
    console.debug(timestamp(), "E", util.format(format, ...rest));
  }
}

(async function main(args) {
  let nb_hops = 3;
  let arg_url = '';
  for (const arg of args) {
    if (arg === '-v') {
      logLevel = LogLevels.warn;
    } else if (arg === '-vv') {
      logLevel = LogLevels.info;
    } else if (arg === '-vvv') {
      logLevel = LogLevels.debug;
    } else if (arg.length === 1 && arg[0] >= '0' && arg[0] <= '9') {
      nb_hops = parseInt(arg, 10);
    } else {
      arg_url = arg;
    }
  }
  if (!arg_url) {
    console.log('Wrong usage\nUsage: %s [-v|-vv|-vvv] [nb_hops] url');
    return;
  }

  const uri = url.parse(arg_url);
  if (!uri.port) {
    uri.port = (uri.protocol === 'https:' ? 443 : 80).toString();
  }

  const logger = new Logger();

  /** @type Socket */
  let socket;
  /** @type Circuit */
  let circuit;
  try {
    const home = process.env.HOME || process.env.USERPROFILE;
    const app_cache_path = path.join(home, '.cache', 'mini-tor-js');
    const cached_consensus_path = path.join(app_cache_path, 'cached-consensus')
    fs.mkdirSync(app_cache_path, { recursive: true });
    // Load consensus
    const consensus = new Consensus(logger);
    await consensus.fetch(cached_consensus_path);
    consensus.set_allowed_dir_ports(80, 443);
    // Connect relays path
    const hop_count = () => circuit ? circuit.node_list.length : 0;
    const forbidden_routers = [];
    while(hop_count() < nb_hops) {
      if (hop_count() === 0) { // Entry
        // Connect to first OR
        const entry_or = consensus.get_random_onion_router_by_criteria({
          or_ports: [80, 443],
          flags: OR.valid | OR.running | OR.fast,
          forbidden_routers
        });
        socket = new Socket(logger);
        await socket.connect(entry_or);
        if (!socket.is_connected()) {
          logger.error("Could not connect to", entry_or.name);
          return;
        }
        circuit = await socket.create_circuit();
        if (!circuit || hop_count() < 1) {
          logger.error("Could not create circuit to", entry_or.name);
          await socket.close();
        } else {
          forbidden_routers.push(entry_or.identity_fingerprint.toString('hex'));
          logger.info("Connected to", entry_or.name);
        }
      } else if (hop_count() === nb_hops - 1) { // Exit
        const exit_or = consensus.get_random_onion_router_by_criteria({
          flags: OR.valid | OR.running | OR.fast | OR.exit,
          forbidden_routers
        });
        const before = hop_count();
        await circuit.extend(exit_or, 'ntor');
        if (hop_count() === before) {
          logger.error("Could not create circuit to", exit_or.name);
        } else {
          logger.info("Extended to exit", exit_or.name);
        }
      } else { // Middle(s)
        const relay_or = consensus.get_random_onion_router_by_criteria({
          flags: OR.valid | OR.running | OR.fast,
          forbidden_routers
        });
        const before = hop_count();
        await circuit.extend(relay_or, 'ntor');
        if (hop_count() === before) {
          logger.error("Could not extend circuit to", relay_or.name);
        } else {
          forbidden_routers.push(relay_or.identity_fingerprint.toString('hex'));
          logger.info("Extended to", relay_or.name);
        }
      }
    }
    /** @type TorStream */
    let tor_stream;
    if (uri.hostname.endsWith('.onion')) {
      const onion = uri.hostname.substr(0, uri.hostname.length - 6);
      tor_stream = await circuit.create_onion_stream(onion, uri.port);
    } else {
      tor_stream = await circuit.create_stream(uri.hostname, uri.port);
    }
    if (!tor_stream) {
      logger.error("Could not create stream to", uri.href);
      return;
    }
    const stream = tor_stream.get_stream();
    const result = await get(uri.protocol, uri.hostname, uri.port, uri.path, stream);
    console.log(result);
  } catch (err) {
    logger.error(err);
  } finally {
    circuit && await circuit.destroy();
    socket && await socket.close();
  }
})(process.argv.slice(2));