/**
 * Try to unlock the door with auth mode
 */

const redis = require('redis');

function doorStatusKey(id) {
  return concatKeys("doors", id, 'open');
}

function concatKeys(...keys) {
  return keys.join(':');
}

exports.handler = function(context, event, callback) {
  const response = new Twilio.Response();

  let door = event.door;
  let pin = event.key;

  if (!door || !pin) {
    response.setStatusCode(400);
    return callback(null, response);
  }

  if (!context['FIXED_PIN_' + door.toUpperCase()]) {
    response.setStatusCode(404);
    return callback(null, response);
  }

  let correctPin = context['FIXED_PIN_' + door.toUpperCase()];

  if (correctPin !== pin) {
    response.setStatusCode(401);
    return callback(null, response);
  }

  let client = redis.createClient({ url: context.REDIS_CONNECT_URL });
  client.connect()
    .then(async () => {
      const statusKey = doorStatusKey(door);
      const fingerprint = { method: "PIN" };
      const timeout = context['OPEN_TIMEOUT_' + door.toUpperCase()] || 60;
      
      await client.set(statusKey, JSON.stringify(fingerprint));
      await client.expire(statusKey, timeout);
      await client.quit();
      
      response
        .setStatusCode(200)
        .appendHeader('Content-Type', 'application/json')
        .setBody({ msg: `Opened the door "${door}" for ${timeout}s` });

      return callback(null, response);
    });
};