defmodule Irc.Shout do
  alias Irc.{Connection, Line}

  def shout(nick, host, target, message, opts \\ []) do
    opts = opts
           |> Keyword.put(:reconnect, false)
           |> Keyword.put_new(:await_up_timeout, :timer.seconds(30))
           |> Keyword.put_new(:quit, "bye")
    do_shout(Connection.start(nick, host, opts), target, message, opts)
  end

  def do_shout({:ok, conn}, target, message, opts) do
    mon = Process.monitor(conn)
    result = with \
         {_, {:ok, _info}} <- {:await_up, Connection.await_up(conn, Keyword.get(opts, :await_up_timeout))},
         {_, :ok} <- {:join, join(conn, target)},
         {_, :ok} <- {:send, Connection.sendline(conn, ['PRIVMSG ', target, ' :', message])}
    do
      :ok
    else
      error ->
        error
    end
    Process.demonitor(mon, [:flush])
    Connection.disconnect(conn, Keyword.get(opts, :quit), true)
    Connection.flush(conn)
    result
  end

  def do_shout(error, _, _, _) do
    error
  end

  def join(conn, target = "#"<>_) do
    case Connection.sendline(conn, ['JOIN ', target]) do
      :ok -> await_join(conn, target)
      error -> error
    end
  end

  def join(conn, _) do
    :ok
  end

  def await_join(conn, target) do
    receive do
      {:irc_conn_line, conn, %Line{command: "JOIN", args: [target]}} -> :ok
      {:irc_conn_error, conn, reason} -> {:error, reason}
      {:DOWN, _, _, conn, reason} -> {:error, {:conn_down, reason}}
    after
      10_000 -> :join_timeout
    end
  end


end