#!/bin/bash
#     queued is a simple daemon for starting jobs to queue of calculations
#     Copyright (C) 2013 Evgeniy Alekseev
# 
#     This program is free software; you can redistribute it and/or modify
#     it under the terms of the GNU 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 the
#     GNU General Public License for more details.
# 
#     You should have received a copy of the GNU General Public License
#     along with this program; if not, see http://www.gnu.org/licenses
#     or write to the Free Software Foundation,Inc., 51 Franklin Street,
#     Fifth Floor, Boston, MA 02110-1301  USA

# functions
error_mes() {
  case "$1" in
    "config"   ) echo "[EE] Configuration file is not set";;
    "notfound" ) echo "[EE] File '$2' not found";;
    "number"   ) echo "[EE] '$2' is not a number";;
    "priority" ) echo "[EE] Priority is not set";;
    "unknown"  ) echo "[EE] Unknown error";;
    "user"     ) echo "[EE] User is not set";;
  esac
  exit 1
}
func_help() {
  echo -e "Script to add job for queued"
  echo -e "\nUsage: add_queued [ -c /etc/queued.conf ] [ -p NUM ] [ -u USER ] [ -h | --help ] /path/to/script"
  echo -e "\nParameters:"
  echo -e "  -c               PATH     - path to configuration file. Default is '/etc/queued.conf'"
  echo -e "  -p               NUM      - job priority"
  echo -e "  -u               USER     - username"
  echo -e "  -h   --help               - show this help and exit"
  exit 0
}
isnum() {
    (t=$(( 0$1+0 ))) 2>/dev/null
}


CONF_FILE="/etc/queued.conf"
# parametrs parsing
until [ -z $1 ]; do
  case "$1" in
    "-h" | "--help"    ) func_help;;
    "-c"               ) [ -z "$2" ] && error_mes "config" || CONF_FILE="$2" && shift;;
    "-p"               ) [ -z "$2" ] && error_mes "priority" || JOB_PRIORITY="$2" && shift;;
    "-u"               ) [ -z "$2" ] && error_mes "user" || JOB_USER="$2" && shift;;
    *                  ) JOB_SCRIPT="$1";;
  esac
  shift
done
# default values
WORKDIR="/var/lib/queued/work"
echo "[II] Reading configuration from '$CONF_FILE'"
[ -e "$CONF_FILE" ] || error_mes "notfound" "$CONF_FILE"
for VAR in "$(cat "$CONF_FILE")"; do eval "$VAR"; done

# error check
if [ ! -d "$WORKDIR" ]; then
  [ -e "$WORKDIR" ] && error_mes "file" "$WORKDIR"
  echo "[II] Creating directory '$WORKDIR'"
  mkdir -m777 -p "$WORKDIR" || error_mes "unknown"
fi
if [ ! -z "$JOB_PRIORITY" ]; then
  isnum "$JOB_PRIORITY" || error_mes "number" "$JOB_PRIORITY"
fi
[ -z "$JOB_SCRIPT" ] && error_mes "notfound" "$JOB_SCRIPT"
[ -e "$JOB_SCRIPT" ] || error_mes "notfound" "$JOB_SCRIPT"


# work block
if [ -e "$WORKDIR/$(basename "$JOB_SCRIPT")" ]; then
  echo "[WW] File '$WORKDIR/$(basename "$JOB_SCRIPT")' already exists. Creating backup"
  mv "$WORKDIR/$(basename "$JOB_SCRIPT")" "$WORKDIR/$(basename "$JOB_SCRIPT")-$(date +%Y%m%d-%N)" || error_mes "unknown"
fi
echo "[II] Copying '$JOB_SCRIPT' to '$WORKDIR'"
cp --archive "$JOB_SCRIPT" "$WORKDIR" || error_mes "unknown"
if [ ! -z "$JOB_PRIORITY" ]; then
  echo "$JOB_PRIORITY" > "$WORKDIR/$(basename "$JOB_SCRIPT").pr" || error_mes "unknown"
fi
if [ ! -z "$JOB_USER" ]; then
  echo "$JOB_USER" > "$WORKDIR/$(basename "$JOB_SCRIPT").user" || error_mes "unknown"
fi

exit 0