#!/bin/bash

################################################################################
#                                                                              #
#  Copyright (C) 2014 Jack-Benny Persson <jack-benny@cyberinfo.se>             #
#                                                                              #
#   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 2 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, write to the Free Software                #
#   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA  #
#                                                                              #
################################################################################


TapeFile=tape.txt
HowMany=6
TimeStamp=`date "+%F %X --> "`

# Parse command line options
while getopts i:h Opt; do
	case "$Opt" in
	i) printf "$TimeStamp Tape ${OPTARG}\n" >> $TapeFile
	   exit 0
	   ;;
	h) printf " Usage: `basename $0` -i <int> -h\n"
	   printf " -i Initalize (or start over) with this tape number\n"
	   printf " -h This help screen\n"
	   exit 0
	   ;;
	*) printf "Unknown opton, see -h (help) for more information\n"
	   ;;
	esac
done

# Check if file exist
if [ ! -e $TapeFile ]; then
	printf "$TapeFile dosen't exist, please use the -i option to init it\n"
	exit 2
fi

Tape=`tail -n1 $TapeFile | awk '{ print $5 }'`

# Check if file contains tape data
if [[ $Tape != [0-9] ]]; then
	printf "$TapeFile dosen't seem to contain tape data\n"
	printf "Use -i <int> to initizalize tape date\n"
	printf "See help (-h) for more information\n"
	exit 2
fi

# Once we reach the latest tape, rotate
if [ $Tape -ge $HowMany ]; then
	Tape=0
fi

# Else add 1 to the tape number
Tape=$((Tape+1))

# Print it to file
printf "$TimeStamp Tape $Tape\n" >> $TapeFile


exit 0