ircd-js/src/server.js

const net = require("net")
const User = require("../src/user.js")

const RPL_WELCOME = '001'
const ERR_NOSUCHNICK = '401'
const ERR_NOSUCHCHANNEL = '403'
const ERR_CANNOTSENDTOCHAN = '404'
const ERR_UNKNOWNCOMMAND = '421'
const ERR_ERRONEUSNICKNAME = '432'
const ERR_NONICKNAMEGIVEN = '431'
const ERR_NICKNAMEINUSE = '433'
const ERR_NEEDMOREPARAMS = '461'

let server = {}

server.create = function create(config = {}) {
    let password
    if (config.password) {
      password = config.password
    }
    let userlist = {}
    let server = net.createServer((socket) => {
        const user = new User(socket)
        if (!config.password) {
          user.authenticated = true
        }
        socket.on('data', function (data) {
            data.toString("ascii").split("\r\n").forEach(function (commandline) {
              if (commandline == "") {
                return
              }
              let splitted = commandline.split(" ")
              let tokenized = []
              let lastParam = -1
              for (let i = 0; i < splitted.length; i++) {
                  if (lastParam > 0) {
                      tokenized[lastParam] = tokenized[lastParam] + " " + splitted[i]
                  } else if (splitted[i].charAt(0) == ":" && i > 0) {
                      lastParam = i
                      tokenized[lastParam] = splitted[i].slice(1)
                  } else {
                      tokenized[i] = splitted[i]
                  }
              }
              let command = tokenized[0].toUpperCase()
              switch (command) {
                  case  "PING":
                      if (tokenized[1] && tokenized[1] === "irc.example.com") {
                          socket.write("PONG irc.example.com\r\n")
                      }
                      break;
                  case "NICK":
                      if (tokenized[1]) {
                          let nickname = tokenized[1]
                          // nick collision test
                          if (!Object.keys(userlist).includes(nickname)) {
                              user.setNickname(nickname)
                              userlist[user.nickname] = user
                          } else {
                              socket.write(ERR_NICKNAMEINUSE, " nickname in use")
                          }


                      } else {
                          socket.write(ERR_NONICKNAMEGIVEN, "ERROR: NO NICKNAME PROVIDED")
                      }

                      break;

                  case "USER":
                      // ignoring servername and hostname, not useful these days
                      user.register(tokenized[1], tokenized[4])
                      let address = user.getAddress()
                      socket.write(`:irc.example.com 001 ${user.nickname} :Welcome to the example IRC Project ${user.nickname}!~${user.username}@${address}\r\n`, "ascii")
                      break;
                  case "PRIVMSG":
                      let target = userlist[tokenized[1]]
                      let message = tokenized[2]

                    target.sendMsg(user, message)
                    break;
                  case "QUIT":
                    server.closeConnection(user.nickname)
                    break;
                  case "PASS":
                    if (tokenized[1] === config.password) {
                        user.authenticated = true
                    } else {
                        user.closeConnection()
                    }
                    break;

                  default:
                    console.error(`Unknown command: ${command}`);
            }
          });
        }).on('error', (err) => {
            console.error(err);
        })
    }).on('error', (err) => {
        console.error(err);
        throw err;
    });

    server.getUserlist = function () {
        return userlist
    }

    server.closeConnection = function (user_nickname) {
        let user = userlist[user_nickname]
        user.closeConnection()
        delete userlist[user_nickname];
    }

    return server
}


module.exports = server