#! /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: toppatch [-bpnfa] [patchname]"
	if [ x$1 = x-h ]
	then
		cat <<EOF

Print the name of the topmost patch on the current stack
of applied patches, or the names of one or more patches
relative to this patch.

-b	Print the names of all patches before the
	topmost or specified patch.

-p	Print the name of the previous patch in the
	series.

-n	Print the name of the next patch in the series.

-f	Print the names of all patches following the
	topmost or specified patch.

-a	Print the names of all patches in the file series.

EOF
		exit 0
	else
		exit 1
	fi
}

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

if [ $? -ne 0 ]
then
	usage
fi

eval set -- "$options"

opt_what=here

while true
do
	case "$1" in
	-b)
		opt_what=before
		shift ;;
	-p)
		opt_what=previous
		shift ;;
	-n)
		opt_what=next
		shift ;;
	-f)
		opt_what=follow
		shift ;;
	-a)
		opt_what=all
		shift ;;
	-h)
		usage -h ;;
	--)
		shift
		break ;;
	esac
done

if [ $# -gt 1 ]
then
	usage
elif [ $# -eq 1 ]
then
	opt_patch=$1
fi

if [ -n "$opt_patch" ]
then
	patch=$(stripit $opt_patch)
else
	patch=$(top_patch)
fi

case $opt_what in
before)
	if [ -n "$patch" ]
	then
		patches_before $patch
	fi
	;;
previous)
	if [ -n "$patch" ]
	then
		patches_before $patch | tail -1
	fi
	;;
here)
	if [ -n "$patch" ]
	then
		echo $patch
	fi
	;;
next)
	if [ -z "$patch" ]
	then
		cat_series | head -1
	else
		patches_after $patch | head -1
	fi
	;;
follow)
	if [ -z "$patch" ]
	then
		cat_series
	else
		patches_after $patch
	fi
	;;
all)
	cat_series
	;;
esac