#! /bin/bash

###############################################################################
#
# DMRIDUpdate.sh
#
# Copyright (C) 2016 by Tony Corbett G0WFV
#
# 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., 675 Mass Ave, Cambridge, MA 02139, USA.
#
###############################################################################
#
# On a Linux based system, such as a Raspberry Pi, this script will perform all 
# the steps required to maintain the DMRIds.dat (or similar) file for you.
#
# It is designed to run from crontab and will download the latest IDs from the 
# master DMR-MARC ID database and optionally keep a backup of previously
# created files for you.
#
# It will also prune the number of backup files according to a value specified
# by you in the configuration below.
#
# When done, it will restart MMDVMHost to make the ID changes take effect.
#
# To install in root's crontab use the command ...
#
#     sudo crontab -e
#
# ... and add the following line to the bottom of the file ...
#
#     0  0  *  *  *  /path/to/script/DMRIDUpdate.sh 1>/dev/null 2>&1
#
# ... where /path/to/script/ should be replaced by the path to this script.
#
###############################################################################
#
#                              CONFIGURATION
#
# Full path to DMR ID file, without final slash
DMRIDPATH=/path/to/DMR/ID/file
DMRIDFILE=${DMRIDPATH}/DMRIds.dat

# DMR IDs now served by RadioID.net
DATABASEURL='https://database.radioid.net/static/user.csv'

#
# How many DMR ID files do you want backed up (0 = do not keep backups)
DMRFILEBACKUP=1
#
# Command line to restart MMDVMHost
RESTARTCOMMAND="systemctl restart mmdvmhost.service"
# RESTARTCOMMAND="killall MMDVMHost ; /path/to/MMDVMHost/executable/MMDVMHost /path/to/MMDVM/ini/file/MMDVM.ini"

###############################################################################
#
# Do not edit below here
#
###############################################################################

# Check we are root
if [ "$(id -u)" != "0" ] 
then
	echo "This script must be run as root" 1>&2
	exit 1
fi

# Create backup of old file
if [ ${DMRFILEBACKUP} -ne 0 ]
then
	cp ${DMRIDFILE} ${DMRIDFILE}.$(date +%d%m%y)
fi

# Prune backups
BACKUPCOUNT=$(ls ${DMRIDFILE}.* | wc -l)
BACKUPSTODELETE=$(expr ${BACKUPCOUNT} - ${DMRFILEBACKUP})

if [ ${BACKUPCOUNT} -gt ${DMRFILEBACKUP} ]
then
	for f in $(ls -tr ${DMRIDFILE}.* | head -${BACKUPSTODELETE})
	do
		rm $f
	done
fi

# Generate new file
curl ${DATABASEURL} 2>/dev/null | sed -e 's/\t//g' | awk -F"," '/,/{gsub(/ /, "", $2); printf "%s\t%s\t%s\n", $1, $2, $3}' | sed -e 's/\(.\) .*/\1/g' > ${DMRIDPATH}/DMRIds.tmp
NUMOFLINES=$(wc -l ${DMRIDPATH}/DMRIds.tmp | awk '{print $1}')
if [ $NUMOFLINES -gt 1 ]
then
   mv ${DMRIDPATH}/DMRIds.tmp ${DMRIDFILE}
else
   echo " ERROR during file update "
   rm ${DMRIDPATH}/DMRIds.tmp
fi

# Restart MMDVMHost
eval ${RESTARTCOMMAND}