debug()
{
	#echo "$@" >&2
	true
}

if [ -n "$PATCHSCRIPTS" ]
then
	P=$PATCHSCRIPTS/
else
	unset P
fi

if [ -e .pc/series ]
then
	SERIES=.pc/series
elif [ -e series ]
then
	SERIES=series
else
	SERIES=${P}patches/series
fi

DB=".pc/applied-patches"

quote_re()
{
	echo "$1" | sed -e 's:\([/.+*\[\\]\):\\\1:g'
}

patch_file_name()
{
	local patch=$1

	if [ -e $SERIES ]
	then
		awk '/^'"$(quote_re $patch)"'(|\.patch|\.diff?)([ \t]|$)/ \
			{ printf "'"$P"'patches/%s\n", $1; exit }' \
		    $SERIES
	fi
}

# The -pN option and possibly others that should be passed to patch.
patch_args()
{
	local patch=$1

	if [ -e $SERIES ]
	then
		awk '/^'"$(quote_re $patch)"'(|\.patch|\.diff?)([ \t]|$)/ \
			{ if (NF >= 2)
				for (i=2; i <= NF; i++)
					print $i ;
			  else print "-p1" ;
			  exit }' \
		    $SERIES
	fi
}

patch_strip_level()
{
	local patch=$1 i
	for i in $(patch_args $patch)
	do
		case $i in
		-p)
			echo $2
			return ;;
		-p*)
			echo ${i:2}
			return ;;
		esac
	done
	echo "1"
}

change_db_strip_level()
{
	local level=$1 patch=$2

	if [ x$level != x-p1 ]
	then
		level="$level"
	else
		level=""
	fi

	if [ -e $SERIES ]
	then
		local tmp=$(mktemp /tmp/patch-scripts.XXXXXX)
		awk '/^'"$(quote_re $patch)"'(\.patch|\.diff?)([ \t]|$)/ \
			{for(i=2; i<=NF; i++)
				if ($i ~ /^-p/)
					{$i="'"$level"'" ; break}
			 if (i > NF)
				 $i="'"$level"'"}
			{print}' \
		    $SERIES > $tmp
		if cmp $SERIES $tmp >/dev/null 2>/dev/null
		then
			rm -f $tmp
		else
			mv -f $tmp $SERIES
		fi
	else
		return 1
	fi
}

patch_in_series()
{
	local patch=$1

	if ! [ -e $SERIES ]
	then
		return 1
	else
		grep -q '^'"$(quote_re $patch)"'\(\|\.patch\|.diff\?\)\([ \t]\|$\)' $SERIES
	fi
}

# Insert new patch after topmost patch
insert_in_series()
{
	local patch=$1 patch_args=$2
	local top=$(top_patch) tmp

	if [ -n "$patch_args" ]
	then
		patch_args=" $patch_args"
	fi

	tmp=$(mktemp /tmp/patch-scripts.XXXXXX) || return 1
	if [ -n "$top" ]
	then
		awk '		{ print }
		     /^'"$(quote_re $top)"'(|\.patch|\.diff?)([ \t]|$)/ \
		     		{ print "'"$patch$patch_args"'" }' \
		    < $SERIES \
		    > $tmp \
		    || return 1
	else
		echo $patch$patch_args > $tmp
		if [ -e $SERIES ]
		then
			cat $SERIES >> $tmp
		fi
	fi
	mkdir -p $(dirname $SERIES)
	mv -f $tmp $SERIES
}

pc_file_name()
{
	while [ $# -gt 0 ]
	do
		echo ".pc/$1/.pc"
		shift
	done

}

backup_file_name()
{
	local patch=$1
	while [ $# -gt 1 ]
	do
		echo ".pc/$patch/$2"
		shift
	done
}

__cat_series()
{
	local series=$1
	if [ -e $series ]
	then
		sed -e '/^#/d' -e 's/^[ \t]*//' -e 's/[ \t].*//' \
		    -e 's/\.patch$//' -e 's/\.diff\?//' $series
	else
		return 1
	fi
}

cat_series()
{
	__cat_series $SERIES
}

top_patch()
{
	[ -e $DB ] && tail -1 $DB
}

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

is_numeric()
{
	echo $1 | grep -q -e '^[0-9]*$'
}

is_applied_last()
{
	local patch=$1
	[ "$(top_patch)" == $patch ]
}

is_applied()
{
	local patch=$1
	[ -e $DB ] || return 1
	grep -q "^$patch\$" $DB
}

patches_before()
{
	local patch=$1
	cat_series \
	| awk '$0 == "'"$patch"'"	{ exit }
					{ print }'
}

patches_after()
{
	local patch=$1
	cat_series \
	| awk 'seen			{ print }
	       $0 == "'"$patch"'"	{ seen=1 }'
}

# List all patches that have been applied on top of patch $1
patches_on_top_of()
{
	local patch=$1
	[ -e $DB ] || return
	awk '$0 == "'"$patch"'"		{ seen=1 ; next }
	     seen			{ print }' $DB
}

# Print the name of the patch that modified the file $2 next after
# patch $1, or print nothing if patch $1 is on top.
next_patch_for_file()
{
	local patch=$1 file=$2
	local patches_on_top=$(patches_on_top_of $patch)

	if [ -n "$patches_on_top" ]
	then
		grep -l -e "^$(quote_re $file)\$" \
			$(pc_file_name $patches_on_top) \
		| head -1 \
		| sed -e 's:^\.pc/::' -e 's:/\.pc$::'
	fi
}

can_apply()
{
	local silent
	if [ "x$1" == "x-s" ]
	then
		silent=-s
		shift
	fi
	local patch=$1
	patch -p1 --dry-run -f $silent -i $(patch_file_name $patch) < /dev/null
}

can_remove()
{
	local silent
	if [ "x$1" == "x-s" ]
	then
		silent=-s
		shift
	fi
	local patch=$1
	patch -R -p1 --dry-run -f $silent -i $(patch_file_name $patch) < /dev/null
}

add_to_db()
{
	echo $1 >> $DB
}

remove_from_db()
{
	local patch=$1
	local tmpfile
	tmpfile=$(mktemp /tmp/patch-scripts.XXXXXX)
	grep -v "^$patch\$" $DB > $tmpfile
	mv -f $tmpfile $DB
	[ -s $DB ] || rm -f $DB
}

stripit()
{
	if [ -n "$1" ]
	then
		echo $1 |
		sed -e 's/^\(\.\/\)*//' \
		    -e 's/^'"$P"'patches\///' -e 's/^\.pc\///' \
		    -e 's/\.patch$//' -e 's/\.diff\?$//'
	fi
}

file_in_patch()
{
	local file=$1 patch=$2
	files_in_patch $patch | grep -q "^$file\$"
}

files_in_patch()
{
	local pc_file=$(pc_file_name $1)
	if [ -e "$pc_file" ]
	then
		cat $pc_file
	fi
}

install_file_in_patch()
{
	local file=$1 patch=$2 bup_file=$(backup_file_name $patch $file)
	
	if ! echo $file  @LIB@/backup-file -s -B .pc/$patch/ || \
	   ! echo $file >> $(pc_file_name $patch)
	then
		return 1
	fi
}

refresh_file_list()
{
	local patch=$1
	local pc_file=$(pc_file_name $patch)
	local patch_file=$(patch_file_name $patch)
	
	if ! [ -e "$patch_file" ]
	then
		echo "Patch file $patch_file does not exist"
		return 1
	fi
	if [ ! -e $pc_file -o $pc_file -ot $patch_file ]
	then
		mkdir -p $(dirname $pc_file)
		echo "touched-by-patch $(patch_strip_level $patch) $patch_file > $pc_file" >&2
		@LIB@/touched-by-patch -p$(patch_strip_level $patch) \
			$patch_file > $pc_file
		if [ $? -ne 0 ]
		then
			return 1
		fi
		return 2
	fi
}

directory_names()
{
	echo "$@" \
	| awk 'BEGIN	{RS=" "}
			{sub(/\/?[^\/]*$/, "") ; printf "[%s]\n", $0}
			{if (last != $0)
				print last
			 last = $0}
		END	{print last}'
}

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

patch_description()
{
	local patch_file=$1

	if [ -e "$patch_file" ]
	then
		awk	'/^--- /	{exit}
			 diff		{print diff ; diff=""}
			 /^diff /	{diff=$0 ; next}
					{print}' \
			$patch_file
	fi
}