#!/bin/sh
# treeprune - remove files from current tree when they match a target tree
#
# Copyright Tony Aiuto 1990-1992
#
# 11/29/90 tony - removed redundent first are, add -e option
#		- better error checking
# 01/07/91 tony - add -x flag to only check executables, -h flag for Harsh mode
# 10/04/92 tony - remove recol references
# 02/24/98 tony - add pre-remove symbolic links and post-remove directories
#
# Send comments and money to tony@aiu.to
#


Edit=0
exeOnly=0
harsh=0
EDITOR=${EDITOR:-vi}

while [ -n "$1" ] ; do
	case $1 in
	-e )
		Edit=1
		shift
		;;
	-x )
		exeOnly=1
		shift
		;;
	-h )
		harsh=1
		shift
		;;
	-* )
		echo "treeprune: unknown option $1"
		exit 1
		;;
	* )
		break
		;;
	esac
done


if [ $# -ne 1 ] ; then
	echo 'usage: treeprune [-e] [-h] [-x] TargetDirectory
	-e	allow edit of file list before pruning
	-h	harsh mode: existance of matching name causes delete
	-x	only check executable files (as determined by file command)
'
	exit 1
fi
to=$1

if [ ! -d $to ] ; then
	echo $to is not a directory
	exit 2
fi

curPath=`pwd`
toPath=`(cd $to ; pwd)`

if [ $curPath = $toPath ] ; then
	echo "You can't prune against your current directory"
	exit 3
fi

echo Pruning files from $curPath against $toPath

trap "rm -f /tmp/$$ ; exit 0" 0 1 2 3 4 15

# first remove symbolic links
find . -type l -exec /bin/rm \{} \;

# now get the list of files
find . -type f -print >/tmp/$$

if [ $exeOnly -ne 0 ] ; then
	echo Executables only.
	xargs file </tmp/$$ | grep 'executable' | cut -d: -f1 >/tmp/$$.1
	mv /tmp/$$.1 /tmp/$$
fi

if [ $Edit -ne 0 ] ; then
	$EDITOR /tmp/$$
fi

if [ $harsh -ne 0 ] ; then
	echo Pruning harshly, mere existance is enough for the prune
	while read i
	do
		if [ -r $to/$i ] ; then
			rm -f $i
		fi
	done </tmp/$$
	# finally - remove empty directories
	find . -type d -depth -print | grep -v '^\.$' | xargs /bin/rmdir
	exit 0
fi

while read i
do
	case $i in
	*.Z )
		if [ -f $to/$i ] ; then
			if (cmp $i $to/$i >/dev/null) ; then
				rm -f $i
			fi
		else
			basei=`expr $i : '\(.*\).Z$'`
			if [ -f $to/$basei ] ; then
				if (zcat $i | cmp - $to/$basei >/dev/null); then
					rm -f $i
				fi
			fi
		fi
		;;
	*.gz )
		if [ -f $to/$i ] ; then
			if (cmp $i $to/$i >/dev/null) ; then
				rm -f $i
			fi
		else
			basei=`expr $i : '\(.*\).gz$'`
			if [ -f $to/$basei ] ; then
			    if (gzip -d <$i | cmp - $to/$basei >/dev/null); then
				rm -f $i
			    fi
			fi
		fi
		;;
	* )
		if (cmp $i $to/$i >/dev/null) ; then
			rm -f $i
		fi
		;;
	esac
done </tmp/$$

# finally - remove empty directories
find . -type d -depth -print | grep -v '^\.$' | xargs /bin/rmdir

exit 0