#! /usr/bin/env 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 [ "$(type -t patch_file_name)" != function ]
then
	if ! [ -r $QUILT_DIR/scripts/patchfns ]
	then
		echo "Cannot read library $QUILT_DIR/scripts/patchfns" >&2
		exit 1
	fi
	. $QUILT_DIR/scripts/patchfns
fi

usage()
{
	printf $"Usage: quilt snapshot [-d]\n"
	if [ x$1 = x-h ]
	then
		printf $"
Take a snapshot of the current working state.  After taking the snapshot,
the tree can be modified in the usual ways, including pushing and
popping patches.  A diff against the tree at the moment of the
snapshot can be generated with \`quilt diff --snapshot'.

-d	Only remove current snapshot.
"
		exit 0
	else
		exit 1
	fi
}

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

if [ $? -ne 0 ]
then
	usage
fi

eval set -- "$options"

while true
do
	case "$1" in
	-d)
		opt_remove=1
		shift ;;
	-h)
		usage -h ;;
	--)
		shift
		break ;;
	esac
done

if [ $# -ne 0 ]
then
	usage
fi

snap_subdir=.snap

# Clean up from previous snapshot
rm -rf $QUILT_PC/$snap_subdir
if [ -n "$opt_remove" ]
then
	exit 0
fi

# Save current working state
create_db
mkdir -p $QUILT_PC/$snap_subdir
for patch in $(applied_patches); do
	files_in_patch $patch
done \
| awk ' # filter out duplicates
	{ if (seen[$0])
	      next
	  seen[$0] = 1
	}
	{ print }
' \
| $QUILT_DIR/scripts/backup-files -c -s -f - -B "$QUILT_PC/$snap_subdir/"