const debug = require('debug')('log4js:tcp-server');
const net = require('net');
const clustering = require('../clustering');
const LoggingEvent = require('../LoggingEvent');

const DELIMITER = '__LOG4JS__';

exports.configure = (config) => {
  debug('configure called with ', config);

  const server = net.createServer((socket) => {
    let dataSoFar = '';
    const send = (data) => {
      if (data) {
        dataSoFar += data;
        if (dataSoFar.indexOf(DELIMITER)) {
          const events = dataSoFar.split(DELIMITER);
          if (!dataSoFar.endsWith(DELIMITER)) {
            dataSoFar = events.pop();
          } else {
            dataSoFar = '';
          }
          events
            .filter((e) => e.length)
            .forEach((e) => {
              clustering.send(LoggingEvent.deserialise(e));
            });
        } else {
          dataSoFar = '';
        }
      }
    };
    socket.setEncoding('utf8');
    socket.on('data', send);
    socket.on('end', send);
  });

  server.listen(config.port || 5000, config.host || 'localhost', () => {
    debug(`listening on ${config.host || 'localhost'}:${config.port || 5000}`);
    server.unref();
  });

  return {
    shutdown: (cb) => {
      debug('shutdown called.');
      server.close(cb);
    },
  };
};