#!/bin/bash -eE
# (c) Nicolás Reynolds <fauno@parabola.nu>
# Released under GPLv3
#
# Performs chroot cleanup smartly, it only removes the unneeded packages or
# leaves you with a cleansystem
#
# See: HOOKPREBUILD

DRYRUN=${DRYRUN:-false}

################################################################################
# Define these here to avoid having dependencies on outside files

msg() {
	local mesg=$1; shift
	printf "${GREEN}==>${ALL_OFF}${BOLD} ${mesg}${ALL_OFF}\n" "$@" >&2
}

msg2() {
	local mesg=$1; shift
	printf "${BLUE}  ->${ALL_OFF}${BOLD} ${mesg}${ALL_OFF}\n" "$@" >&2
}

error() {
	local mesg=$1; shift
	printf "${RED}==> $(gettext "ERROR:")${ALL_OFF}${BOLD} ${mesg}${ALL_OFF}\n" "$@" >&2
}

################################################################################

if [[ ! -f /.arch-chroot ]] && ! ${DRYRUN}; then
	error "(chcleanup): Must be run inside of a chroot"
	exit 1
fi

source /etc/libretools.d/chroot.conf
# If we're running makepkg
if [ -f PKGBUILD ]; then
	export CARCH="$(. /etc/makepkg.conf; printf '%s' "$CARCH")"
	source PKGBUILD
	CHROOTEXTRAPKG+=("${depends[@]}"
	                 "${makedepends[@]}"
	                 "${checkdepends[@]}")
fi

msg "Cleaning chroot..."

pacman -Sy || true

TEMPDIR="$(mktemp --tmpdir -d $(basename $0).XXXXX)"
cp -a /var/lib/pacman/sync "${TEMPDIR}/"
cleanup_log="${TEMPDIR}"/libretools-cleanup.log

# Get the full list of packages needed by dependencies, including the base system
pacman -b "${TEMPDIR}" \
       -Sp --print-format "%n" \
	base-devel "${CHROOTEXTRAPKG[@]}" \
       >"${cleanup_log}"

# Diff installed packages against a clean chroot then remove leftovers
packages=($(comm -23 <(pacman -Qq | sort -u) \
                     <(sort -u "${cleanup_log}")))

RET=0
if [[ ${#packages[@]} != 0 ]]; then
	msg2 "Removing %d packages" ${#packages[@]}

	if ${DRYRUN}; then
		echo "${packages[@]}"
	else
		# Only remove leftovers, -Rcs removes too much
		pacman --noconfirm -Rn "${packages[@]}" || RET=$?
	fi
fi
# Cleanup
rm -rf "${TEMPDIR}"

exit $RET