#!/bin/sh

set -e

if [ "$(id -u)" != "0" ]; then
	echo "Must be root." >&2
	exit 1
fi

WORKDIR="/var/cache/freebsd-sets-update"
ARCH=$(uname -p)
BRANCH="head"
REVISION="latest_tested"
SETS="base kernel"

URL=
DO_DEBUG=
DO_LOCAL=
DO_ETCUPDATE=

usage()
{
	echo "Usage: $0 [-b branch] [-l localdir] [-r revision] [-dev]"
	echo "   -b: branch (head, stable-11 or stable-12)"
	echo "   -d: add debug sets"
	echo "   -e: execute etcupdate"
	echo "   -l: directory where sets are located"
	echo "   -r: try to find sets for this revision"
	echo "   -v: show executed commands"
}

while getopts b:del:r:v OPT; do
	case ${OPT} in
	b)
		BRANCH=${OPTARG}
		;;
	d)
		DO_DEBUG="1"
		SETS="${SETS} base-dbg kernel-dbg"
		;;
	e)
		DO_ETCUPDATE="1"
		;;
	l)
		DO_LOCAL="1"
		WORKDIR=${OPTARG}
		;;
	r)
		REVISION=${OPTARG}
		;;
	v)
		set -x
		;;
	*)
		usage
		exit 1
		;;
	esac
done

shift $((${OPTIND} - 1))

if [ -n "${*}" ]; then
	echo "Arguments are not supported" >&2
	exit 1
fi


get_url()
{
	echo "http://artifacts.ci.freebsd.org/snapshot/${BRANCH}/${1}/${ARCH}/${ARCH}"
}

exit_msg()
{
	if [ -n "${1}" ]; then
		echo "${1}"
	fi
	exit 1
}

fetch_sets()
{
	url=$(get_url $REVISION)
	fetch -o ${WORKDIR}/MANIFEST ${url}/MANIFEST
	for set in $SETS; do
		fetch -o ${WORKDIR}/${set}.txz ${url}/${set}.txz
	done
}

install_kernel()
{
	echo -n "Installing ${REVISION} kernel.txz..."

	if ! mkdir -p /boot/kernel /boot/kernel.old /usr/lib/debug/boot/kernel /usr/lib/debug/boot/kernel.old; then
		exit_msg " failed, mkdir error ${?}"
	fi

	if ! rm -r /boot/kernel.old /usr/lib/debug/boot/kernel.old; then
		exit_msg " failed, rm error ${?}"
	fi

	if ! mv /boot/kernel /boot/kernel.old; then
		exit_msg " failed, mv error ${?}"
	fi

	if ! mv /usr/lib/debug/boot/kernel /usr/lib/debug/boot/kernel.old; then
		exit_msg " failed, mv error ${?}"
	fi
	if ! tar -C / -xpf ${WORKDIR}/kernel.txz; then
		exit_msg " failed, tar error ${?}"
	fi

	if [ -n "${DO_DEBUG}" ]; then
		echo -n " and kernel-dbg.txz..."
		if ! tar -C / -xpf ${WORKDIR}/kernel-dbg.txz; then
			exit_msg " failed, tar error ${?}"
		fi
	fi

	if ! kldxref /boot/kernel; then
		exit_msg " failed, kldxref error ${?}"
	fi

	echo " done"
}

install_base()
{
	NOSCHGDIRS="/bin /sbin /lib /libexec /usr/bin /usr/sbin /usr/lib /var/empty"

	echo -n "Installing ${REVISION} base.txz..."

	if ! mkdir -p ${NOSCHGDIRS}; then
		exit_msg " failed, mkdir error ${?}"
	fi

	if ! chflags -R noschg ${NOSCHGDIRS}; then
		exit_msg " failed, chflags error ${?}"
	fi

	if ! tar -C / -xpf ${WORKDIR}/base.txz --exclude="^etc" ; then
		exit_msg " failed, tar error ${?}"
	fi
	if [ -n "$DO_ETCUPDATE" ]; then
		if ! mkdir ${WORKDIR}/etc; then
			exit_msg " failed, mkdir error ${?}"
		fi
		if ! tar -C ${WORKDIR}/etc --include "^etc" -xpf ${WORKDIR}/base.txz; then
			exit_msg " failed, tar error ${?}"
		fi
		if ! tar -C ${WORKDIR}/etc -cJf ${WORKDIR}/etc.txz .; then
			exit_msg " failed, tar error ${?}"
		fi
		if ! etcupdate -I "/[^e][^t][^c]*"  -t ${WORKDIR}/etc.txz ; then
			exit_msg " failed, etcupdate error ${?}"
		fi
	fi
	if [ -n "${DO_DEBUG}" ]; then
		echo -n " and base-dbg.txz..."
		if ! tar -C / -xpf ${WORKDIR}/base-dbg.txz; then
			exit_msg " failed, tar error ${?}"
		fi
	fi

	echo " done"
}

if [ -z "$DO_LOCAL" ]; then
	REVISION=$(fetch -o - -q "$(get_url ${REVISION})/revision.txt")
	WORKDIR="${WORKDIR}/${REVISION}"
	if uname -v | grep -q "${REVISION}" ; then
		exit_msg "Already at version ${REVISION}"
	fi
	if [ ! -d "${WORKDIR}" ]; then
		if ! mkdir -p ${WORKDIR}; then
			exit_msg " failed, mkdir error ${?}"
		fi
		fetch_sets
	fi
fi

install_kernel
install_base

echo "Upgrade done"