#!/bin/bash -eu
#
# Create quilt patch series and include-binaries file
#

function out()
{
	local rc=${?}

	trap - EXIT INT TERM HUP
	if [ ${rc} -ne 0 ] ; then
		echo "Error: Script failed" >&2
	fi

	exit "${rc}"
}

function add_file()
{
	local added=${1} name=${2}

	if [ -z "${name}" ] || [ "${name#debian/}" != "${name}" ] ; then
		# Empty name or debian/* file
		return
	fi

	if [ -h "${name}" ] ; then
		# Symlink
		BINARIES+=("${name}")
		PATCHABLES+=("${name}")
	elif [ "${added}" = "-" ] ; then
		# Binary file
		BINARIES+=("${name}")
	else
		# Patchable file
		PATCHABLES+=("${name}")
	fi
}

trap out EXIT INT TERM HUP

# Current upstream commit
version=$(dpkg-parsechangelog -Sversion)
upstream=${version#*.git}
upstream=${upstream%%-*}

BINARIES=()
PATCHABLES=()

# Walk through all touched files and separate them into binaries that need to
# be included and patchable files
while IFS=" " read -r added name new_name ; do
	add_file "${added}" "${name}"
	add_file "${added}" "${new_name}"
done < <(git diff --numstat "${upstream}" | awk '{ print $1 " " $3 " " $5 }')

if [ ${#BINARIES[@]} -gt 0 ] ; then
	echo "Create debian/source/include-binaries ..."
	printf "%s\n" "${BINARIES[@]}" > debian/source/include-binaries
fi

rm -rf debian/patches
install -d debian/patches

if [ ${#PATCHABLES[@]} -gt 0 ] ; then
	echo "Create debian/patches/ubuntu.patch ..."
	for patchable in "${PATCHABLES[@]}" ; do
		git diff "${upstream}" -- "${patchable}"
	done > debian/patches/ubuntu.patch
	echo ubuntu.patch > debian/patches/series
fi