#!/bin/bash

#
# update_physrpi - Update Raspberry Pi configuration for physics class
#
# 19Sep18  Updated for course-independent configuration
# 20Jun18  Updated for 129m18, multi-course configuration
# 02Apr18  Updated for 129s18
# 15Jan18  Adapted from update_129m17 by Everett Lipman
#

cd $HOME
if [ $? -ne 0 ]
then
   echo >&2
   echo "could not change to directory $HOME .  Exiting." >&2
   echo >&2
   exit 1
fi

TRM="physrpi"
CONFDIR="config_$TRM"
TARFILE="${CONFDIR}.tar.gz"
URL="http://web.physics.ucsb.edu/~rpi/$TARFILE"

RMFILES="config*${TRM}*.tar* ./Downloads/config*${TRM}*.tar*"
SETUP="setup_physrpi"

PROGNAME=`basename $0`
USAGE="$PROGNAME"
NARGS=`expr \`echo $USAGE | wc -w\` - 1`

error_exit()
{
echo ""
echo $1
echo ""
echo "$PROGNAME exiting."
echo ""
exit 1
}

errorcheck()
{
if [ $? -ne 0 ]
then
   error_exit "Error $1"
fi
}

if [ $# -ne $NARGS ]
then
   error_exit "usage: $USAGE"
fi
###############################################################################

echo
echo "Updating up your Raspberry Pi for physics class..."
echo
###############################################################################

#
# clear old tar files
#
\rm -f $RMFILES
errorcheck "clearing old tar files"

wget $URL
errorcheck "downloading configuration tar file"

\rm -rf $CONFDIR

tar zxf $TARFILE
errorcheck "upacking configuration tar file $TARFILE"

cd $CONFDIR
errorcheck "changing to configuration directory $CONFDIR"
###############################################################################

exec ./$SETUP