#! /bin/sh 

# makediffs -- create a shell script to recreate dir2, given dir1
#
# $Id: makediffs,v 2.1 1997/09/10 06:30:41 cdua Exp cdua $
# Carlos Duarte, 970901

checkdir() {
	if test -d $1 ; then 
		: 
	else
		echo $1: can not access $1 as a directory...
		exit 1
	fi
	case $1 in /*) 
		echo $1: must be relative directory... 
		exit 1
		;;
	esac
}

unsupported() {
cat <<\EOF
One of the given dirs contains files with spaces ( ) or colons (:).
makediffs does not support thoses files, because: 
  - files with colon messes around with output of the file(1) command
  - files with spaces messes around with general sh processing

EOF
	exit 1
}

DIFF="diff -c"

# args
if test $# -ne 2; then 
	echo usage : $0 old-dir new-dir
	echo
	echo \  writes diff script to output
	exit 1
fi

old=$1
new=$2
cur=`pwd`

checkdir $old
checkdir $new

wdir=/tmp/zmd%$$
i=1
while test -d $wdir.$i
do
	i=`expr $i + 1`
done

wdir=$wdir.$i
mkdir $wdir

cd $cur/$old && find . \( -type d -fprint $wdir/o.d \) -o -fprint $wdir/o.f
cd $cur/$new && find . \( -type d -fprint $wdir/n.d \) -o -fprint $wdir/n.f

grep '[: ]' $wdir/* >/dev/null && unsupported 

cd $cur/$old && xargs -r file < $wdir/o.f > $wdir/ff.o
cd $cur/$new && xargs -r file < $wdir/n.f > $wdir/ff.n

cd $wdir
sed '/^[^:]*:.*text.*$/ d; s/:.*$//' < ff.o | sort > special.old
sed '/^[^:]*:.*text.*$/ d; s/:.*$//' < ff.n | sort > special.new

sed '/^[^:]*:.*text.*$/!d; s/:.*$//' < ff.o | sort > text.old
sed '/^[^:]*:.*text.*$/!d; s/:.*$//' < ff.n | sort > text.new

cat<< EOF
#! /bin/sh
#
# This is a script produced by $0 shell script. 
# cd into original package ($old) and run it. 
# 
# Some sanity checks will be made.

# Sanity check... 
EOF
D1=`sed -n 2p o.d`
D2=`sed -n 4p o.d`
F1=`sed -n 1p o.f`
F2=`sed -n 3p o.f`
echo 'if test x = x \'
test x$D1 != x && echo \&\& test -d $D1 \\
test x$D2 != x && echo \&\& test -d $D2 \\
test x$F1 != x && echo \&\& test -f $F1 \\
test x$F2 != x && echo \&\& test -f $F2 \\
cat << EOF
; then 
	:
else
	echo 'You should run this script on original directory ($old ?)...'
	exit 1
fi

# extra files...
xargs -r rm -f << \XARGS_EOF
EOF

diff special.old special.new | sed -n '
/^< /s/^..//p
/^> /s/^..//w ftar
'

diff text.old text.new | sed -n '
/^< /s/^..//p
/^> /s:^..\(.*\):/dev/null \1:w fnew
'

echo 'XARGS_EOF'

echo '# directories to remove'
echo 'xargs -r rmdir << \XARGS_EOF'
sort -o o.d o.d
sort -o n.d n.d
diff o.d n.d | sed -n '
/^< /s/^..//p
/^> /s/^..//w mkd
' | sort -r

echo 'XARGS_EOF'

# here: 
# 	$wdir/mkd	contain dirs to make, one per line
# 	$wdir/fnew	files to creat, format: "/dev/null file" 
# 	$wdir/ftar	file to make thru tar

echo '# new directories'
echo 'xargs -r mkdir << \XARGS_EOF'
cat mkd
echo 'XARGS_EOF'

sort text.old text.new \
  | uniq -d \
  | sed 's:.*:& &:' >> fnew

cd $cur

echo '# extra file deletions' 
echo 'xargs -r rm -f << \XARGS_EOF'

touch $wdir/p.0
i=0
cat $wdir/fnew | while read oo nn ; do 

	if test $oo = "/dev/null"; then
		i=`expr $i + 1`
		$DIFF /dev/null $new/$nn  > $wdir/p.$i
		continue
	fi

	if cmp $old/$oo $new/$nn >/dev/null; then
		continue
	fi
		
	i=`expr $i + 1`
	$DIFF $old/$oo $new/$nn > $wdir/p.$i

	if test `wc -c < $wdir/p.$i` -gt `wc -c < $new/$nn`; then
		echo $oo
		$DIFF /dev/null $new/$nn > $wdir/p.$i
	fi
done

echo 'XARGS_EOF'
echo 'patch -p1 << \PATCH_EOF'
cat $wdir/p.*
echo 'PATCH_EOF'

cd $wdir
sort special.old special.new | uniq -d | while read f; do
	if test -f $cur/$old/$f && \
	   test -f $cur/$new/$f && \
	   cmp $cur/$old/$f $cur/$new/$f >/dev/null; then
		: 
	else
		echo $f >> ftar
	fi
done

cd $cur/$new 
if test -s $wdir/ftar; then
	tar cf $wdir/t.tar `sed 1q $wdir/ftar`
	sed 1d $wdir/ftar | xargs -r tar rf $wdir/t.tar 

	cat << \EOF
C=`sed '/^## START OF TAR DATA ##/q' $0 | wc -c `
C=`expr $C + 0`
dd if=$0 of=/tmp/md.$$.dm bs=$C skip=1 2>/dev/null
tar xf /tmp/md.$$.dm
rm -f /tmp/md.$$.dm
exit 
## START OF TAR DATA ## 
EOF
	cat $wdir/t.tar
else
	echo exit
fi

rm -rf $wdir
exit 0