#! /bin/bash

#  This script is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License version 2 as
#  published by the Free Software Foundation.
#
#  See the COPYING and AUTHORS files for more details.

# Read in library functions
if ! [ -r @LIB@/patchfns ]
then
	echo "Cannot read library @LIB@/patchfns" >&2
	exit 1
fi
. @LIB@/patchfns

usage()
{
	echo "Usage: poppatch [-afRq] [npatches|patchname]"
	if [ x$1 = x-h ]
	then
		cat <<EOF

Remove patch(es) from the current stack. A number of
patches to remove, or a patch name can be specified. If a
patch name is given, remove all patches up to and
including the named patch. If neither a number nor a patch
name is specified, remove the next patch.

-a	Remove all patches in the series file.

-f	Force remove. The state before the patch(es) were
	applied will be restored from backup files.

-R	Remove the patch with \`patch -R' and check if the
	patch reverts all changes properly.

-q	Quiet operation.

EOF
		exit 0
	else
		exit 1
	fi
}

list_patches()
{
	local top=$(top_patch) n=0 patch
	if [ -z "$top" ]
	then
		return 0
	fi
	( patches_before $top
	  echo $top ) \
	| tac \
	| if [ -n "$opt_all" ]
	then
		cat
	else
		while read patch
		do
			if [ -n "$number" ]
			then
				if [ $n -eq $number ]
				then
					break
				fi
				n=$[$n+1]
			fi
			echo $patch
			if [ $patch = "$stop_at_patch" ]
			then
				break
			fi
		done
		if [ -n "$stop_at_patch" -a "$patch" != "$stop_at_patch" ]
		then
			echo "Patch $stop_at_patch not found in file series" >&2
			return 1
		fi
	fi
}

options=`getopt -o fRqah -- "$@"`

if [ $? -ne 0 ]
then
        usage
fi

eval set -- "$options"

while true
do
        case "$1" in
        -f)
                opt_force=1
		unset opt_remove
		shift ;;
	-R)
		opt_remove=1	# remove with patch -R; no tricks
		unset opt_force
		shift ;;
        -q)
                opt_quiet=1
		shift ;;
	-a)
		opt_all=1
		shift ;;
	-h)
		usage -h ;;
        --)
                shift
		break ;;
        esac
done

if [ $# -gt 1 ]
then
        usage
fi

if [ $# -eq 1 ]
then
	if is_numeric $1
	then
		number=$1
	else
		stop_at_patch=$(stripit $1)
	fi
else
	[ -n "$opt_all" ] || number=1
fi

[ -n "$opt_force" ] &&
	rpatch_options="$rpatch_options -f"
[ -n "$opt_remove" ] &&
	rpatch_options="$rpatch_options -R"
[ -n "$opt_quiet" ] &&
	rpatch_options="$rpatch_options -q"

if [ -n "$stop_at_patch" ]
then
	if ! is_applied $stop_at_patch
	then
		echo "Patch $stop_at_patch is not applied."
		exit 1
	fi
fi

if ! patches=$(list_patches) 2>&1
then
	exit 1
elif [ -z "$patches" ]
then
        echo "No patches removed"
	exit 0
fi

trap "interrupted=1" SIGINT

for patch in $patches
do
	if ! @LIB@/rpatch $rpatch_options $patch
	then
		echo Still at patch $patch
		exit 1
	fi
	if [ -n "$interrupted" ]
	then
		echo "poppatch interrupted by user"
		exit 1
	fi
	[ -z "$opt_quiet" ] && echo
done