#!/bin/bash

set -e

if [ $# -eq 2 ]; then
  user="$(whoami)_$(hostname)"
  channel="$1"
  message="$2"
elif [ $# -eq 3 ]; then
  user="$1"
  channel="$2"
  message="$3"
else
  echo 'Need 2 or 3 arguments: (user) channel message.'
  exit 1
fi

pid=''

clean_up() {
  rm -rf --one-file-system "${tmp_dir}"
  if [ -n "${pid}" ]; then
    kill ${pid}
  fi
}
tmp_dir="$(mktemp -d)"
trap clean_up EXIT

mkfifo "${tmp_dir}/input"
mkfifo "${tmp_dir}/output"

ncat irc.home.eckner.net 6667 < \
  "${tmp_dir}/input" > \
  "${tmp_dir}/output" &
pid=$!

(
  printf '%s\n' 'NICK '"${user}" 'USER '"${user}"' 8 * : '"${user}"

  while read -r s; do
  echo "$s" >&2
    if [[ "${s}" = *"MODES"* ]]; then
      printf '%s\n' 'JOIN '"${channel}" 'PRIVMSG '"${channel}"' :'"${message}" 'QUIT'
    fi
  done \
    < "${tmp_dir}/output"
) \
  > "${tmp_dir}/input"

unset pid