#!/bin/sh

set -e

case "$(basename ${0})" in
	d*)
		MODE="debian"
		;;

	p*)
		MODE="progress-linux"
		;;

	b*)
		MODE="bfh"
		;;
esac

case "${MODE}" in
	debian)
		DOWNSTREAM_BRANCH=""
		;;

	progress-linux)
		DOWNSTREAM_BRANCH="progress-linux"
		;;

	bfh)
		DOWNSTREAM_BRANCH="bfh"
		;;
esac

RED="\033[1;33;31m"
GREEN="\033[1;33;32m"
YELLOW="\033[1;33;33m"
BLUE="\033[1;33;34m"
WHITE="\033[1;33;37m"
NORMAL="\033[0m"
PURPLE="\033[1;33;35m"

DSC="${1}"

case "${DSC}" in
	*.dsc)
		;;

	*)
		echo "Usage: ${0} DSC"
		exit 1
		;;
esac

case "${DSC}" in
	http*)
		DSC_TEMPDIR="$(mktemp -d)"

		cd "${DSC_TEMPDIR}"
		dget -u -d "${DSC}"
		cd "${OLDPWD}"

		DSC="${DSC_TEMPDIR}/$(basename ${DSC})"
		;;
esac

PACKAGE="$(basename ${DSC} | awk -F_ '{ print $1 }')"
DEB_VERSION="$(awk '/^Version: / { print $2 }' ${DSC})"

case "${DEB_VERSION}" in
	*-*)
		DEB_UPSTREAM_VERSION="$(echo ${DEB_VERSION} | awk -F- '{ $NF=""; print $0 }' | sed -e 's| |-|g' -e 's|-$||g')"
		;;

	*)
		DEB_UPSTREAM_VERSION="${DEB_VERSION}"
		;;
esac

Switch_upstream_branch ()
{
	CURRENT_BRANCH="$(git branch --show-current)"

	if [ "${CURRENT_BRANCH}" != "upstream" ] && git branch | grep -qs upstream
	then
		echo
		echo "################################################################################"
		echo "git: switching to upstream branch"
		echo "################################################################################"

		git checkout upstream
	fi
}

Remove_everything ()
{
	echo
	echo "################################################################################"
	echo "git: removing all files"
	echo "################################################################################"

	echo -n "Removing files for new import..."

	find . -maxdepth 1 -mindepth 1 -and -not -name .git -print0 | xargs -0 -I '{}' rm -rf '{}'

	echo " done."
}

Unpack_upstream ()
{
	echo
	echo "################################################################################"
	echo "dpkg: unpacking upstream files"
	echo "################################################################################"

	TEMPDIR="$(mktemp -d -p . -u)"

	dpkg-source -x --no-copy --skip-debianization ${DSC} "${TEMPDIR}"
	rm -rf "${TEMPDIR}/debian"
	find "${TEMPDIR}" -type d -name ".git" -exec rm -rf {} \; || true

	DEBIAN_TAR="$(dirname $(readlink -f ${DSC}))/$(awk '/debian.tar.*$/ { print $3 }' ${DSC} | head -n1)"

	case "${DEBIAN_TAR}" in
		*.debian.tar.*)
			if [ -e "${DEBIAN_TAR}" ]
			then
				# this includes upstream additions outside debian/ into the upstream branch
				cd "${TEMPDIR}"
				tar xf "${DEBIAN_TAR}"
				rm -rf debian
				rm -rf .git
				cd "${OLDPWD}"
			fi
			;;
	esac

	find "${TEMPDIR}" -maxdepth 1 -mindepth 1 -print0 | xargs -0 -I '{}' mv '{}' .
	rmdir "${TEMPDIR}"
}

Add_upstream_version ()
{
	echo
	echo "################################################################################"
	echo "git: adding upstream version"
	echo "################################################################################"

	# FIXME
	git-upstream-add ${DEB_UPSTREAM_VERSION}
}

Switch_debian_branch ()
{
	CURRENT_BRANCH="$(git branch --show-current)"

	if [ "${CURRENT_BRANCH}" != "debian" ] && git branch | grep -qs debian
	then
		echo
		echo "################################################################################"
		echo "git: switching to debian branch"
		echo "################################################################################"

		git checkout debian
	fi
}

Unpack_debian ()
{
	echo
	echo "################################################################################"
	echo "dpkg: unpacking debian files"
	echo "################################################################################"

	TEMPDIR="$(mktemp -d -p . -u)"

	dpkg-source -x --no-copy --skip-patches ${DSC} ${TEMPDIR}
	find "${TEMPDIR}" -type d -name ".git" -exec rm -rf {} \; || true
	rm -rf "${TEMPDIR}/debian/.debputy"

	find "${TEMPDIR}" -maxdepth 1 -mindepth 1 -print0 | xargs -0 -I '{}' mv '{}' .

	rmdir ${TEMPDIR}
}

Add_debian_version ()
{
	echo
	echo "################################################################################"
	echo "git: adding debian version"
	echo "################################################################################"

	# FIXME
	git-debian-add
}

Switch_downstream_branch ()
{
	CURRENT_BRANCH="$(git branch --show-current)"

	if [ "${CURRENT_BRANCH}" != "${DOWNSTREAM_BRANCH}" ] && git branch | grep -qs ${DOWNSTREAM_BRANCH}
	then
		echo
		echo "################################################################################"
		echo "git: switching to downstream branch"
		echo "################################################################################"

		git checkout ${DOWNSTREAM_BRANCH}
	fi
}

Merge_upstream_version ()
{
	git cherry-pick -n --allow-empty upstream
	git commit -a -s -S -m "Merging upstream version ${DEB_UPSTREAM_VERSION}."
}

Merge_debian_version ()
{
	git cherry-pick -n debian
	git commit -a -s -S -m "Merging debian version ${DEB_VERSION}."
}

echo "################################################################################"
echo "git: importing ${DSC}"
echo "################################################################################"

GIT_UPSTREAM_VERSION="$(git tag | awk -F/ '/^upstream\// { print $2 }' | sort -rV | head -n1 | sed -e 's|%|:|g' -e 's|_|~|g')"

if [ "${DEB_UPSTREAM_VERSION}" != "${GIT_UPSTREAM_VERSION}" ]
then
	Switch_upstream_branch

	Remove_everything
	Unpack_upstream
	Add_upstream_version

	MERGE_UPSTREAM="true"
fi

GIT_DEBIAN_VERSION="$(git tag | awk -F/ '/^debian\// { print $2 }' | sort -rV | head -n1 | sed -e 's|%|:|g' -e 's|_|~|g')"

if [ "${DEB_VERSION}" != "${GIT_DEBIAN_VERSION}" ]
then
	Switch_debian_branch

	case "${MERGE_UPSTREAM}" in
		true)
			Merge_upstream_version
			;;
	esac

	Remove_everything
	Unpack_debian
	Add_debian_version

	MERGE_DEBIAN="true"
fi

if [ -n "${DSC_TEMPDIR}" ]
then
	rm -rf "${DSC_TEMPDIR}"
fi

if [ "${MERGE_DEBIAN}" = "true" ] && [ -n "${DOWNSTREAM_BRANCH}" ]
then
	Switch_downstream_branch

	case "${MERGE_UPSTREAM}" in
		true)
			Merge_upstream_version
			;;
	esac

	Merge_debian_version
fi