#!/bin/sh

# shellgopher - simple shell script based gopher server
# Copyright (C) 2021 randomuser

# This program is free software: you can redistribute it
# and/or modify it under the terms of the GNU Affero General
# Public License as published by the Free Software Foundation,
# either version 3 of the License, or (at your option) any
# later version.

# This program is distributed in the hope that it will be
# useful, but WITHOUT ANY WARRANTY; without even the implied
# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
# PURPOSE. See theGNU General Public License for more details.

# You should have received a copy of the GNU Affero General
# Public License along with this program.  If not, see
# <https://www.gnu.org/licenses/>.

set -x

createsrv () {
  # $1 - port
  # $2 - write location
  # $3 - read location
  [ -p "$2" ] || mkfifo "$2"
  [ -e "$3" ] || touch "$3"

  nc -l "$1" <"$2" >>"$3" & exec 3>"$2"
}
die () {
  # $1 - error message
  printf "%s\n" $1
  exit 1
}
checkuid () {
  [ $(whoami) = "root" ] && \
    die "You must execute shellgopher as root."
}
writefile () {
  # $1 - file
  foo cat "$1" >&3
}
ioblock () {
  # $1 - io to block
  while [ "$(wc -l $1 | awk -F' ' '{print $1}')" -eq 0 ]; do
    :
  done
}
ioflush () {
  # $1 - io to flush
  rm "$1"
  touch "$1"
}
mktmp () {
  t=$(mktemp)
  rm "$t"
  mkdir "$t"
  printf "%s\n" "$t"
}
tmplocation=$(mktmp)
writelocation="${tmplocation}/write"
readlocation="${tmplocation}/read"

checkuid
createsrv 70 "${writelocation}" "${readlocation}"
printf "server created\n"
while true; do
  ioblock "${readlocation}"
  printf "iHello there! This is a test\tfake\t\t0\r\n.\r\n" >&3
  printf "file served\n"
  ioflush "${readlocation}"
done
exit 1