IRC bridge

irc-bridge.lua

local event = require("event")
local fs = require("filesystem")
local srl = require("serialization")
local thread = require("thread")

local irc = require("irc")
local events = irc.events
local priority = events.priority

local com = require("component")
local chatbox = com.admin_chatbox
local debug = com.debug
local gpu = com.gpu

local colors = {"02", "03", "04", "13", "08", "09", "11", "06"}

local function formatNick(nick)
  local modulo = #colors + 1
  local result = 0

  for char in nick:gmatch(".") do
    result = (result + char:byte()) % modulo
  end

  if result == 0 then
    return ("\x0f%s"):format(nick)
  else
    return ("\x02\x03%s%s"):format(colors[result], nick)
  end
end

local defaultCfg = {
  channel = "",
  nickname = "s1-conversationalist",
  username = "conversationalist",
  realname = "IRC-MC bridge relay",
  account = "s1-conversationlist",
  accountPassword = "",

  mcMessageFormat = "§3[§lIRC§3] §7%s§8: §r%s",
  mcPmFormat = "§3[§lIRC§3 PM] §7%s§8 -> §7%s§8: §r%s",
  ircMessageFormat = "%s\x0f: %s",
  ircPmFormat = "\x0315PM: %s \x0f\x0315-> %s\x0f: %s",
  ircJoinFormat = "\x0315* %s \x0309has joined the server\x0315.",
  ircQuitFormat = "\x0315* %s \x0305has left the server\x0315.",
  ircDeathFormat = "\x0315* %s \x0306has died: \x0f%s\x0315.",

  mcCommandPrefix = "IRC: ",
  mcResponseFormat = "§3[§lIRC§3] §r%s",

  gameAdmins = {},
  ircAdmins = {},

  ircWhitelist = {},
  mcBlacklist = {},

  aliases = {},
  ircPm = {},
  mcPm = {},

  debug = false,
}

local cfgPath =
  os.getenv("CONVERSATIONALIST_CONFIG") or "/etc/conversationalist.cfg"

assert(not fs.exists(cfgPath) or not fs.isDirectory(cfgPath),
       ("%s is a directory"):format(cfgPath))

local cfg

local function saveCfg()
  local serialized = srl.serialize(cfg)

  local f = io.open(cfgPath, "w")
  f:write(serialized)
  f:close()
end

if fs.exists(cfgPath) then
  local f = io.open(cfgPath, "r")
  cfg = srl.unserialize(f:read("*a"))
  f:close()
else
  cfg = defaultCfg
  saveCfg()
  print(("Configuration file written to %s"):format(cfgPath))
  print("Edit and run the program again.")
  os.exit(0)
end

local function isini(tbl, str)
  str = str:lower()

  for k, v in pairs(tbl) do
    if v:lower() == str then
      return true, k
    end
  end

  return false
end

local fg

local function log(color, text)
  if fg ~= color then
    gpu.setForeground(color)
    fg = color
  end

  print(text)
end

local function sanitizeMessage(message)
  return message:gsub("§.?", ""):gsub("%c", "")
end

local handleCommand

local client = irc.builder()
  :connection {
    host = "irc.esper.net:6667",
    throttling = {
      maxDelay = 2,
      maxThroughput = 5,
    },
  }
  :auth {
    username = cfg.username,
    nickname = cfg.nickname,
    realname = cfg.realname,
  }
  :account {
    nickname = cfg.account,
    password = cfg.accountPassword,
  }
  :bot {
    channels = {cfg.channel},
    tracking = {
      account = true,
      users = true,
      modes = true,
    }
  }
  :execution {
    threaded = true,
    reconnect = true,
    catchErrors = true,
  }
  :subscribe(events.irc.message, priority.normal, function(self, client, evt)
    if evt.target ~= cfg.channel then
      return
    end

    local user = client:getUser(evt.source)

    if not user or not user.account then
      return
    end

    if not isini(cfg.ircWhitelist, user.account) then
      return
    end

    local message = sanitizeMessage(evt.message)

    log(0xffdb80, ("IRC → %s: %s"):format(user.account, message))

    event.push("chat::message", user.account, message)
  end)
  :subscribe(events.irc.notice, priority.normal, function(self, client, evt)
    if evt.target ~= "@" .. cfg.channel then
      return
    end

    local user = client:getUser(evt.source)

    if not user or not user.account then
      return
    end

    local admin = isini(cfg.ircAdmins, user.account)

    log(0xffff00, ("! IRC → %s: %s"):format(user.account, evt.message))

    handleCommand(evt, user.account, evt.message, admin)
  end)
  :subscribe(events.client.connected, priority.normal,
             function(self, client, evt)
               log(0x00ff80, "* Connected")
             end)
  :subscribe(events.client.disconnected, priority.normal,
             function(self, client, evt)
               log(0xff0000, "* Disconnected")
             end)
  :subscribe(events.client.registered, priority.normal,
             function(self, client, evt)
               log(0x99ff80, "* Registered as " .. client.botUser.nickname)
             end)
  :subscribe(events.client.authenticated, priority.normal,
             function(self, client, evt)
               log(0x99ff80, "* Authenticated")
               event.push("chat::authenticated")
             end)
  :subscribe(events.client.error, priority.top, function(self, client, evt)
    log(0xff0000, ("Caught error: %s"):format(evt.traceback))
    evt:cancel()
  end)
  :subscribe(events.irc.write, priority.high, function(self, client, evt)
    if cfg.debug then
      log(0x999999, "← " .. evt.line:gsub("[\r\n]+$", ""))
    end
  end)
  :subscribe(events.irc.command, priority.high, function(self, client, evt)
    if cfg.debug then
      log(0xcccccc, "→ " .. evt.rawLine)
    end
  end)
  :build()

local function formatting(irc, mc)
  return function(data)
    return {
      compile = function(self, isIrc)
        local compiled = {}

        for _, v in ipairs(data) do
          if type(v) == "string" then
            table.insert(compiled, v)
          else
            table.insert(compiled, v:compile(isIrc))
          end
        end

        return (isIrc and irc or mc):format(table.concat(compiled))
      end
    }
  end
end

local bold = formatting("\x02%s", "§l%s")
local reset = formatting("\x0f%s", "§r%s")
local red = formatting("\x0305%s", "§c%s")
local green = formatting("\x0309%s", "§a%s")
local cyan = formatting("\x0311%s", "§3%s")
local fmt = formatting("%s", "%s")

local function reply(irc, nickname, msg)
  if type(msg) ~= "string" then
    msg = msg:compile(irc)
  end

  if irc then
    client:notice(irc.source.nickname,
                  ("[%s] %s"):format(cfg.channel, msg))
  else
    chatbox.tell(nickname, cfg.mcResponseFormat:format(msg))
  end
end

local function split(str, n)
  n = n or math.huge
  local parts = {}
  local i = 1

  for part, pos in str:gmatch("(%S+)()") do
    if n == 1 then
      break
    end

    table.insert(parts, part)
    i = pos
    n = n - 1
  end

  local lastPart = str:match("^%s*(%S.-)%s*$", i)

  if lastPart ~= "" then
    table.insert(parts, lastPart)
  end

  return table.unpack(parts)
end

local commands = {
  irc = function(self, irc, nickname, msg, admin)
    if not admin then
      return
    end

    local action, subaction, arg

    if msg then
      action, subaction, arg = split(msg, 3)
    end

    if action == "admin" then
      if subaction == "list" then
        reply(irc, nickname, fmt {
          bold {"IRC bot admins: "},
          reset {table.concat(cfg.ircAdmins, ", ")}
        })
      elseif subaction == "add" and arg then
        table.insert(cfg.ircAdmins, arg)
        saveCfg()
        reply(irc, nickname, bold {"Admin added."})
      elseif subaction == "del" and arg then
        local _, k = isini(cfg.ircAdmins, arg)

        if k then
          table.remove(cfg.ircAdmins, k)
          saveCfg()
          reply(irc, nickname, bold {"Admin removed."})
        else
          reply(irc, nickname, red {"No such user."})
        end
      else
        reply(irc, nickname,
              red {"Available commands: ", reset {"list, add, del"}})
      end
    elseif action == "whitelist" then
      if subaction == "list" then
        reply(irc, nickname, fmt {
          bold {"IRC whitelist: "},
          reset {table.concat(cfg.ircWhitelist, ", ")}
        })
      elseif subaction == "add" and arg then
        if not isini(cfg.ircWhitelist, arg) then
          table.insert(cfg.ircWhitelist, arg)
        end

        saveCfg()
        reply(irc, nickname, bold {"User added."})
      elseif subaction == "del" and arg then
        local _, k = isini(cfg.ircWhitelist, arg)

        if k then
          table.remove(cfg.ircWhitelist, k)
          saveCfg()
          reply(irc, nickname, bold {"User removed."})
        else
          reply(irc, nickname, red {"No such user."})
        end
      else
        reply(irc, nickname,
              red {"Available commands: ", reset {"list, add, del"}})
      end
    elseif action == "alias" then
      local args = arg and {split(arg, 2)} or {}

      if subaction == "get" and args[1] then
        reply(irc, nickname, bold {
          "Alias for ",
          args[1],
          ": ",
          reset {cfg.aliases[args[1]] or cyan {"not set"}}
        })
      elseif subaction == "set" and args[1] then
        cfg.aliases[args[1]] = args[2]
        saveCfg()

        if args[2] then
          reply(irc, nickname, bold {
            "Alias for ",
            args[1],
            " set to ",
            reset {args[2]}
          })
        else
          reply(irc, nickname, bold {
            "Alias for ",
            args[1],
            " has been removed."
          })
        end
      else
        reply(irc, nickname,
              red {"Available commands: ", reset {"get, set"}})
      end
    else
      reply(irc, nickname,
            red {"Available commands: ", reset {"admin, whitelist, alias"}})
    end
  end,

  mc = function(self, irc, nickname, msg, admin)
    if not admin then
      return
    end

    local action, subaction, arg

    if msg then
      action, subaction, arg = split(msg, 3)
    end

    if action == "admin" then
      if subaction == "list" then
        reply(irc, nickname, fmt {
          bold {"MC bot admins: "},
          reset {table.concat(cfg.gameAdmins, ", ")}
        })
      elseif subaction == "add" and arg then
        if not isini(cfg.gameAdmins, arg) then
          table.insert(cfg.gameAdmins, arg)
        end

        saveCfg()
        reply(irc, nickname, bold {"Admin added."})
      elseif subaction == "del" and arg then
        local _, k = isini(cfg.gameAdmins, arg)

        if k then
          table.remove(cfg.gameAdmins, k)
          saveCfg()
          reply(irc, nickname, bold {"Admin removed."})
        else
          reply(irc, nickname, red {"No such user."})
        end
      else
        reply(irc, nickname,
              red {"Available commands: ", reset {"list, add, del"}})
      end
    elseif action == "blacklist" then
      if subaction == "list" then
        reply(irc, nickname, fmt {
          bold {"MC blacklist: "},
          reset {table.concat(cfg.mcBlacklist, ", ")}
        })
      elseif subaction == "add" and arg then
        if not isini(cfg.mcBlacklist, arg) then
          table.insert(cfg.mcBlacklist, arg)
        end

        saveCfg()
        reply(irc, nickname, bold {"User added."})
      elseif subaction == "del" and arg then
        local _, k = isini(cfg.mcBlacklist, arg)

        if k then
          table.remove(cfg.mcBlacklist, k)
          saveCfg()
          reply(irc, nickname, bold {"User removed."})
        else
          reply(irc, nickname, red {"No such user."})
        end
      else
        reply(irc, nickname,
              red {"Available commands: ", reset {"list, add, del"}})
      end
    else
      reply(irc, nickname,
            red {"Available commands: ", reset {"admin, blacklist"}})
    end
  end,

  debug = function(self, irc, nickname, msg, admin)
    if not admin then
      return
    end

    local msg = msg and split(msg, 1)

    if msg == "on" then
      cfg.debug = true
      saveCfg()
      reply(irc, nickname, bold {"Debug mode turned on."})
    elseif msg == "off" then
      cfg.debug = false
      saveCfg()
      reply(irc, nickname, bold {"Debug mode turned off."})
    elseif not msg then
      reply(irc, nickname,
            fmt {"Debug mode is ",
                 bold {cfg.debug and red {"on"} or green {"off"}}, reset {"."}})
    end
  end,

  online = function(self, irc, nickname, msg, admin)
    local users

    if irc then
      users = debug.getPlayers()
    else
      users = {}

      for user, prefix in pairs(client:getChannel(cfg.channel).users) do
        if user.account and user ~= client.botUser then
          table.insert(users, ("§a%s§r%s"):format(prefix, user.account))
        end
      end
    end

    reply(irc, nickname,
          bold {"Users online: ", reset {table.concat(users, ", ")}})
  end,

  pm = function(self, irc, nickname, msg, admin)
    local section = cfg[irc and "ircPm" or "mcPm"]
    local args = msg and {split(msg, 3)} or {}

    if args[1] == "on" then
      section[nickname:lower()] = {}
      saveCfg()

      reply(irc, nickname, bold {
        "PMs from ",
        irc and "MC" or "IRC",
        " have been ",
        green {"enabled"},
      })
    elseif args[1] == "off" then
      section[nickname:lower()] = false
      saveCfg()

      reply(irc, nickname, bold {
        "PMs from ",
        irc and "MC" or "IRC",
        " have been ",
        red {"disabled"}
      })
    elseif args[1] == "ignore" then
      local ignoreList = section[nickname:lower()]

      if not ignoreList then
        reply(irc, nickname, red {
          "PMs from ",
          irc and "MC" or "IRC",
          " are disabled."
        })
      elseif args[2] == "list" then
        reply(irc, nickname, bold {
          "Your ignore list: ",
          reset {table.concat(ignoreList, ", ")}
        })
      elseif args[2] == "add" and args[3] then
        local name = args[3]:lower()

        if not irc then
          for k, v in pairs(cfg.aliases) do
            if v:lower() == name then
              name = k:lower()
              break
            end
          end
        end

        if not isini(ignoreList, name) then
          table.insert(ignoreList, name)
          saveCfg()
        end

        reply(irc, nickname, bold {"You are now ignoring ", reset {name}})
      elseif args[2] == "del" and args[3] then
        local _, k = isini(ignoreList, args[3]:lower())

        if k then
          table.remove(ignoreList, k)
          saveCfg()

          reply(irc, nickname, bold {
            "You no longer ignore ",
            reset {args[3]:lower()}
          })
        else
          reply(irc, nickname, red {"No such user."})
        end
      else
        reply(irc, nickname,
              red {"Available commands: ", reset {"list, add, del"}})
      end
    elseif not args[1] then
      local enabled = section[nickname:lower()]

      if irc and enabled == nil then
        enabled = true
      end

      reply(irc, nickname, bold {
        "PMs from ",
        irc and "MC" or "IRC",
        " are ",
        enabled and green {"enabled"} or red {"disabled"}
      })
    else
      reply(irc, nickname,
            red {"Available commands: ", reset {"on, off, ignore"}})
    end
  end,

  msg = function(self, irc, nickname, msg, admin)
    local addressee, message = split(msg, 2)

    if not addressee or not message then
      reply(irc, nickname, red {"Invalid syntax."})
      return
    end

    local ignoreList = cfg[irc and "mcPm" or "ircPm"][addressee:lower()]

    if (irc and not ignoreList) or (not irc and ignoreList == false) then
      reply(irc, nickname, bold {
        addressee,
        reset {red {" has not enabled PMs from ", irc and "MC" or "IRC"}}
      })
      return
    end

    local ignored = false
    local reason, player, user

    if ignoreList and isini(ignoreList, nickname) then
      ignored = true
    end

    if irc then
      local players = debug.getPlayers()

      for i, nick in ipairs(players) do
        if nick:lower() == addressee:lower() then
          player = nick
          break
        end
      end

      if player then
        if not ignored then
          chatbox.tell(player, cfg.mcPmFormat:format(nickname, player, message))
        end
      else
        reason = "no such user"
      end
    else
      for u in pairs(client:getChannel(cfg.channel).users) do
        if u.account and u.account:lower() == addressee:lower() then
          user = u
          break
        end
      end

      if user then
        if not ignored then
          client:notice(user.nickname,
                        ("[%s]"):format(cfg.channel) ..
                        cfg.ircPmFormat:format(
                          formatNick(nickname),
                          formatNick(user.account),
                          message
                        ))
        end
      else
        reason = "no such user"
      end
    end

    if reason then
      reply(irc, nickname, red {"Message was not sent: ", reason, "."})
    else
      if irc then
        reply(irc, nickname, fmt {cfg.ircPmFormat:format(
          formatNick(nickname),
          formatNick(player),
          message
        )})
      else
        chatbox.tell(
          nickname,
          cfg.mcPmFormat:format(nickname, user.account, message)
        )
      end
    end
  end,
}

function handleCommand(irc, nickname, msg, admin)
  local cmd, rest = split(msg, 2)

  if not cmd then
    return
  end

  if not commands[cmd] then
    return
  end

  commands[cmd](commands[cmd], irc, nickname, rest, admin)
end

local chatThread = thread.create(function()
  event.listen("chat::message", function(evt, nickname, message)
    nickname = cfg.aliases[nickname] or nickname
    chatbox.say(cfg.mcMessageFormat:format(nickname, message))
  end)

  event.listen("chat::authenticated", function()
    event.listen("chat_message",
      function(evt, addr, dim, x, y, z, dist, nickname, msg)
        if isini(cfg.mcBlacklist, nickname) then
          return
        end

        log(0x66dbff, (" MC → %s: %s"):format(nickname, msg))
        client:msg(cfg.channel,
                   cfg.ircMessageFormat:format(formatNick(nickname), msg))
      end)

    event.listen("chat_command",
      function(evt, addr, dim, x, y, z, dist, nickname, msg)
        if msg:sub(1, #cfg.mcCommandPrefix) ~= cfg.mcCommandPrefix then
          return
        end

        msg = msg:sub(#cfg.mcCommandPrefix + 1)

        local admin = isini(cfg.gameAdmins, nickname)
        log(0xffff00, ("!  MC → %s: %s"):format(nickname, msg))
        handleCommand(false, nickname, msg, admin)
      end)

    event.listen("player_join", function(evt, addr, dim, x, y, z, dist, nickname)
      log(0x66dbff, (" MC → %s has joined the server"):format(nickname))
      client:msg(cfg.channel, cfg.ircJoinFormat:format(formatNick(nickname)))
    end)

    event.listen("player_quit", function(evt, addr, dim, x, y, z, dist, nickname)
      log(0x66dbff, (" MC → %s has left the server"):format(nickname))
      client:msg(cfg.channel, cfg.ircQuitFormat:format(formatNick(nickname)))
    end)

    event.listen("player_death",
      function(evt, addr, dim, x, y, z, dist, nickname, reason, msg)
        if isini(cfg.mcBlacklist, nickname) then
          return
        end

        reason = msg or reason

        log(0x66dbff,
            (" MC → %s has died (%s)"):format(nickname, reason))
        client:msg(cfg.channel,
                   cfg.ircDeathFormat:format(formatNick(nickname), reason))
      end)
  end)

  log(0x0092ff, "* Press ^C to quit...")

  repeat
    local evt = event.pull("interrupted")
  until evt
end)

client:run()
thread.waitForAny({client.thread, chatThread})

log(0xff4000, "* Quitting")
client:stop("Quitting.")
gpu.setForeground(0xffffff)
os.exit()