DB=applied-patches

#
# Work out where the user's pc/, patch/ and txt/ directories live.
#
# If the user specified PATCHSCRIPTS in environment then use that (it's
# probably a relative path)
#
# If there is a directory ./patch-scripts then use that
#
# Otherwise use "."
#

if [ x$PATCHSCRIPTS_LIBDIR != x ]
then
	P=$PATCHSCRIPTS_LIBDIR
elif [ -d ./patch-scripts ]
then
	P=./patch-scripts
elif [ -d ./patches ]
then
	P=.
else
	echo "could not locate your pc/ and patches/ directories"
	exit 1
fi

top_patch()
{
	tail -1 $DB
}

die()
{
	echo error: $*
	exit 1
}

is_numeric()
{
	if echo $1 | egrep '^[0-9]*$' > /dev/null
	then
		return 0
	fi
	return 1
}

is_applied_last()
{
	name="$(stripit $1)"
	top_patch >$DB.1
	if grep "^$name$" "$DB.1" > /dev/null 2>&1
	then
		rm $DB.1
		return 0
	else
		rm $DB.1
		return 1
	fi
}

is_applied()
{
	name=$(stripit "$1")
	if grep "^$name$" "$DB" > /dev/null 2>&1
	then
		return 0
	else
		return 1
	fi
}
check_pc_match()
{
	if [ -f /usr/bin/lsdiff ]; then
		tmpfile=$(mktemp /tmp/p_XXXXXX) || exit 1
		lsdiff --strip=1 $1 > $tmpfile 
		diff $2 $tmpfile > /dev/null
		if [ $? != 0 ]; then
			echo " $1 do not match with $2 "
			echo " $2 will be changed to match $2"
			# cat $tmpfile > $P/pc/$PATCH_NAME.pc
		fi
		rm -rf $tmpfile
	fi
} 
can_apply()
{
	if patch -p1 --dry-run -i "$1" -f
	then
		return 0
	else
		return 1
	fi
}

can_remove()
{
	if patch -R -p1 --dry-run -i $P/patches/"$1".patch -f
	then
		return 0
	else
		return 1
	fi
}

remove_from_db()
{
	tmpfile=$(mktemp /tmp/p_XXXXXX)
	name="$1"
	sed -e "/^$name$/d" < "$DB" > $tmpfile
	mv $tmpfile "$DB"
}

stripit()
{
	ret=$(basename $1)
	ret=$(echo $ret | sed -e 's/\.patch$//')
	ret=$(echo $ret | sed -e 's/\.pc$//')
	ret=$(echo $ret | sed -e 's/\.txt$//')
	echo $ret
}

top_is_current()
{
	patch_name=$(top_patch)
	if [ x$patch_name == x ]
	then
		return 1
	else
		patch_file=$P/patches/"$patch_name".patch
		files=$(cat $P/pc/$patch_name.pc)
		for file in $files
		do
			if [ $file -nt $patch_file ]
			then
				echo $file newer than $patch_file
				return 0
			fi
		done
	fi
	return 1
}

need_top_current()
{
	if top_is_current
	then
		echo "Error: Top patch is not up-to-date"
		exit 1
	fi
}

warn_top_current()
{
	if top_is_current
	then
		echo "Warning: Top patch is not up-to-date"
	fi
}

file_in_patch()
{
	file=$1
	patch=$2

	if [ -e $P/pc/$patch.pc ]
	then
		if grep "^"$file"$" $P/pc/$patch.pc > /dev/null
		then
			return 0
		fi
	fi
	return 1
}

# copy_file_to_bup filename patchname
copy_file_to_bup()
{
	file=$1
	patch=$2
	bup="$file"~"$patch"
	orig="$file"~"orig"
	src_dir=`pwd`

	if [ -e $bup ]
	then
		echo "Cannot install file $file in patch $patch: backup $bup exists"
		exit 1
	fi
	if [ -e $file ]
	then
		cp -p $file "$file"~"$patch"
	else
		echo "file $file appears to be newly added"
	fi
	if [ ! -L "$orig" ]; then
		ln -s "$src_dir/$bup" $orig
	fi	
}

install_file_in_patch()
{
	file=$1
	patch=$2

	copy_file_to_bup $file $patch
	echo $file >> $P/pc/$patch.pc
#	touch $P/txt/$patch.txt
}

need_file_there()
{
	if [ ! -e $1 ]
	then
		echo "File $1 does not exist"
		exit 1
	fi
}

desc()
{
	state=0
	while read x
	do
		if [ x"$x" = xDESC ]
		then
			state=1
		elif [ x"$x" = xEDESC ]
		then
			state=0
		elif [ $state = 1 ]
		then
			echo "  $x"
		fi
	done
}

body()
{
	file=$1

	did_stuff=0
	while read x
	do
		if [ x"$x" = xEDESC ]
		then
			cat
			did_stuff=1
		fi
	done < $file

	if [ $did_stuff = 0 ]
	then
		cat $file
	fi
}