#!/bin/sh

# TODO: better isolate listings.gophermap from accidental clobbering

die () {
  msg="$1"
  code="$2"
  # exit code defaults to 1
  if printf "%s" "$code" | grep -q '^[0-9]+$'; then
    code=1
  fi
  # output message to stdout or stderr based on code
  if [ -n "$msg" ]; then
    if [ "$code" -eq 0 ]; then
      printf "%s\\n" "$msg"
    else
      printf "%s\\n" "$msg" >&2
    fi
  fi
  exit "$code"
}

finish () {
  rm -f "$tmp"
}
trap finish EXIT

parse_input () {
  if ! parsed=$(getopt "$arg_options" "$@"); then
    die "Invalid input" 2
  fi

  eval set -- "$parsed"

  while true; do
    case "$1" in
      -h)
        flag_help=1
        arg_log=0
        shift
        ;;
      -v)
        flag_version=1
        arg_log=0
        shift
        ;;
      -d)
        flag_debug=1
        arg_log=0
        shift
        ;;
      -s)
        shift
        arg_ship="$1"
        shift
        ;;
      -z)
        flag_shortlist=1
        shift
        ;;
      -n)
        arg_log=0
        shift
        arg_new="$1"
        shift
        ;;
      --)
        shift
        break
        ;;
      *)
        die "Internal error: $1" 3
        ;;
    esac
  done
}

show_help () {
  printf "%s [-hvd] [-s shipname]\\n\\n" "$(basename "$0")"
  printf "  -h                          Show this help\\n"
  printf "  -v                          Show current version info\\n"
  printf "  -d                          Debug mode\\n"
  printf "  -s [shipname]               Only log messages for ship named\\n"
  printf "  -n [filename]               Create new message with filename\\n"
  printf "                              (Users with multiple ships must use -s)\\n"
  printf "\\n"
  printf "Passing no options will enter interactive mode.\\n\\n"
  printf "\\n"
}

read_key () {
  _key=
  if [ -t 0 ]; then
    if [ -z "$_stty" ]; then
      _stty=$(stty -g)
    fi
    stty -echo -icanon min 1
    _key=$(dd bs=1 count=1 2>/dev/null)
    stty "$_stty"
  fi
}

yesno () {
  read_key
  case $_key in
    y ) result=0 ;;
    * ) result=1 ;;
  esac
  return $result
}

check_log () {
  ship="$*"
  printf ">> %s" "${ship}"
  # look at log entries in gophermap
  # compare against files in ship directory
  # store list of unpublished logs
  logs=$(grep "^0${ship}" "/var/gopher/listing.gophermap" | awk -F'\t' '{print $2}')
  files=$(find "/var/gopher/$ship" -regex ".*\\.txt$" -not -path '*/\.*' -type f | sed 's|/var/gopher||')
  uniq=$(printf "%s\\n%s" "$logs" "$files" | sort | uniq -u)

  if [ -z "$uniq" ]; then
    printf " .... No messages.\\n"
  else
    # check each unpublished message for sending
    IFS='
'
    for u in $uniq
    do
      printf "\\n   Send message %s? " "$(basename "$u" | sed 's/\.[^.]*$//')"
      if yesno; then
        # prompt for title and prepare output
        printf "\\n   Title for message %s? " "$(basename "$u" | sed 's/\.[^.]*$//')"
        read -r title
        if [ ! -z "$title" ]; then
          printf "0%s - %s\\t%s\\n" "$ship" "$title" "$u" | cat - /var/gopher/listing.gophermap > "$tmp" && cat "$tmp" > /var/gopher/listing.gophermap && rm "$tmp"
          printf "\\n   %s - %s .... Sent.\\n" "$(basename "$u" | sed 's/\.[^.]*$//')" "$title"
        else
          printf "   %s .... No title, abort.\\n" "$(basename "$u" | sed 's/\.[^.]*$//')"
        fi
      else
        printf "\\n   %s .... Skipped.\\n" "$(basename "$u" | sed 's/\.[^.]*$//')"
      fi
    done
    unset IFS
  fi
}

new_message () {
  ship="$1"
  post_file="/var/gopher/${ship}/${2}"
  template_file="/var/gopher/${ship}/.template" 
  temp_post=$(mktemp -t "$(basename "$0").post.XXXXXXX") || die "Failed to create temporary file" 1
  if [ -f "$post_file" ]; then
    cp "$post_file" "$temp_post"
  elif [ -f "$template_file" ]; then
    cp "$template_file" "$temp_post"
  fi
  temp_post_time=$(stat -c %Y "$temp_post")
  ${EDITOR:-nano} "$temp_post"
  temp_post_time_check=$(stat -c %Y "$temp_post")
  if [ "$temp_post_time" -ne "$temp_post_time_check" ] ; then
    printf "Drafted message %s (%s)\\n" "$2" "$1"
    touch "${post_file}"
    cat "${temp_post}" > "${post_file}"
    rm "${temp_post}"
  else
    printf "Aborted message.\\n"
    rm "${temp_post}"
  fi
}

main() {
  parse_input "$@"

  # debug
  if [ $flag_debug -gt 0 ]; then
    set -x
  fi

  # shortlist for bash completion
  if [ $flag_shortlist -gt 0 ]; then
    out="$ships"
    die "${out}" 0
  fi

  # version
  if [ $flag_version -gt 0 ]; then
    printf "%s\\n" "$version"
  fi

  # print help
  if [ $flag_help -gt 0 ]; then
    show_help
  fi

  # standard log if no params
  if [ $arg_log -gt 0 ]; then
    printf "INITIALIZING QEC...\\n"
    printf "Ready to transmit for [%s]\\n" "${user}"
    if [ "$numships" -eq 0 ]; then
      printf "No registered ships found in system.\\n"
    elif [ "$numships" -eq 1 ]; then
      if [ -z "$arg_ship" ] || [ "$ships" = "$arg_ship" ]; then
        check_log "$ships"
      fi
    else
      IFS='
'
      for f in $ships
      do
        if [ -z "$arg_ship" ] || [ "$f" = "$arg_ship" ]; then
          check_log "$(basename "$f")"
        fi
      done
      unset IFS
    fi
  fi

  # new message
  if [ ! -z "$arg_new" ]; then
    if [ "$numships" -eq 0 ]; then
      printf "No registered ships found in system.\\n"
    elif [ "$numships" -eq 1 ]; then
      if [ -z "$arg_ship" ] || [ "$ships" = "$arg_ship" ]; then
        new_message "$ships" "$arg_new"
      fi
    else
      IFS='
'
      for f in $ships
      do
        if [ "$f" = "$arg_ship" ]; then
          new_message "$arg_ship" "$arg_new"
        fi
      done
      unset IFS
    fi
  fi
}

##############################################################################
##############################################################################
##############################################################################

version="0.1.0"
user=$(whoami)
ships=$(find /var/gopher -user "$user" -type d -exec basename {} \;)
numships=$(echo "${ships}" | wc -l)
tmp=$(mktemp -t "$(basename "$0").tmp.XXXXXXX") || die "Failed to create temporary file" 1

flag_help=0
flag_version=0
flag_debug=0
flag_shortlist=0

arg_options="hvds:zn:"
arg_log=1
arg_ship=""
arg_new=""

main "$@"