import Boom from 'boom';

export default (target, key, descriptor) => {
  const fn = descriptor.value;

  descriptor.value = async (request, reply) => {
    try {
      await fn(request, reply);
    } catch (e) {
      if (e.original) {
        const { code, detail, hint } = e.original;
        let error;

        // pg error codes https://www.postgresql.org/docs/9.5/static/errcodes-appendix.html
        if (code && (code.startsWith('22') || code.startsWith('23'))) {
          error = Boom.wrap(e, 406);
        } else if (code && (code.startsWith('42'))) {
          error = Boom.wrap(e, 422);
        // TODO: we could get better at parse postgres error codes
        } else {
          // use a 502 error code since the issue is upstream with postgres, not
          // this server
          error = Boom.wrap(e, 502);
        }

        // detail tends to be more specific information. So, if we have it, use.
        if (detail) {
          error.message += `: ${detail}`;
          error.reformat();
        }

        // hint might provide useful information about how to fix the problem
        if (hint) {
          error.message += ` Hint: ${hint}`;
          error.reformat();
        }

        reply(error);
      } else if (!e.isBoom) {
        const { message } = e;
        let err;

        if (e.name === 'SequelizeValidationError')
          err = Boom.badData(message);
        else if (e.name === 'SequelizeConnectionTimedOutError')
          err = Boom.gatewayTimeout(message);
        else if (e.name === 'SequelizeHostNotReachableError')
          err = Boom.serverUnavailable(message);
        else if (e.name === 'SequelizeUniqueConstraintError')
          err = Boom.conflict(message);
        else if (e.name === 'SequelizeForeignKeyConstraintError')
          err = Boom.expectationFailed(message);
        else if (e.name === 'SequelizeExclusionConstraintError')
          err = Boom.expectationFailed(message);
        else if (e.name === 'SequelizeConnectionError')
          err = Boom.badGateway(message);
        else err = Boom.badImplementation(message);

        reply(err);
      } else {
        reply(e);
      }
    }
  };

  return descriptor;
};