var mysql = require('mysql');
var fs = require("fs");

var file = null;
var connectionConfig;
var connection = null;

function handleDisconnect() {
  connection = mysql.createConnection(connectionConfig);

  connection.connect(function(err) {
    if(err) {
      console.log('error when connecting to db:', err);
      setTimeout(handleDisconnect, 2000);
    }
    else {
        console.log("Connected to MySQL database ( "+connectionConfig.user+"@"+connectionConfig.host+"/"+connectionConfig.database+" )");
    }
  });
  connection.on('error', function(err) {
    console.log('db error', err);
    if(err.code === 'PROTOCOL_CONNECTION_LOST') {
      handleDisconnect();
    } else if(err.code === 'ECONNRESET'){
      handleDisconnect();
    } else{
      throw err;
    }
  });
}

try {
    file = fs.readFileSync("./config.json");
}
catch(exception) {
    console.log(exception.toString());
}

if(file != null) {
    var json = JSON.parse(file);

    connectionConfig = {
        host: json.host,
        database: json.database,
        user: json.user,
        password: json.password
    };

    handleDisconnect();
}


module.exports = connection;