#!/bin/bash

GS_SYNC=true
GS_RSYNC=false
GS_EUPDATEDB=true
GS_FETCH=false
GS_UPWORLD=true
GS_LAYMAN=true
GS_DEBUG=false
GS_USER="portage"
conf="/etc/gentoo-sync.conf"
[[ -e ${conf} ]] && . "${conf}"

logdir="/var/log"
sync_log="${logdir}/rsync.log"
up_log="${logdir}/emerge-updates.log"

bootstrap() {
	local prog=$(realpath "$0")
	if [[ "${FLOCKER}" != "${prog}" ]] ; then
		exec env -uUNSHARE FLOCKER="${prog}" flock -en "${prog}" "${prog}" "$@"
	fi

	if [[ -z ${UNSHARE} ]] ; then
		if [[ $(id -u) -ne 0 ]] ; then
			exec sudo env -uUNSHARE FLOCKER="${FLOCKER}" HOME="$HOME" "${prog}" "$@"
		fi

		touch "${sync_log}" "${up_log}"
		chown "${GS_USER}" "${sync_log}" "${up_log}"

		mount_args=
		if type -P unshare >&/dev/null ; then
			test_arg() { unshare "$@" -- true >&/dev/null && uargs+=( "$@" ) || :; }
			uargs=( -m )
			test_arg -u
			test_arg -i
			test_arg -p -f --mount-proc
			test_arg --propagation=private
			exec unshare "${uargs[@]}" -- \
				sudo -u "${GS_USER}" UNSHARE="true" FLOCKER="${FLOCKER}" \
				"${prog}" "$@"
		fi
	else
		mount_args='-n'
	fi
	unset UNSHARE
}
bootstrap "$@"

usage() {
	cat <<-EOF
	Usage: ${0##*/} [options]

	Options:
	  -h, --help
	  -a, --all,      -na, --noall
	  -s, --sync,     -ns, --nosync      ${GS_SYNC}
	  -r, --rsync,    -nr, --norsync     ${GS_RSYNC}
	  -d, --database, -nd, --nodatabase  ${GS_EUPDATEDB}
	  -f, --fetch,    -nf, --nofetch     ${GS_FETCH}
	  -w, --world,    -nw, --noworld     ${GS_UPWORLD}
	  -l, --layman,   -nl, --nolayman    ${GS_LAYMAN}
	  -x, --debug,    -nx, --nodebug     ${GS_DEBUG}
	EOF
	exit 0
}

s() {
	local x val=$1
	shift
	for x ; do
		eval GS_${x}=${val};
	done
}
for x ; do
	case ${x} in
	-h|--help)        usage;;
	-a|--all)         s true  SYNC RSYNC EUPDATEDB FETCH UPWORLD LAYMAN DEBUG;;
	-na|--noall)      s false SYNC RSYNC EUPDATEDB FETCH UPWORLD LAYMAN DEBUG;;
	-s|--sync)        s true  SYNC;;
	-ns|--nosync)     s false SYNC;;
	-r|--rsync)       s true  RSYNC;;
	-nr|--norsync)    s false RSYNC;;
	-d|--database)    s true  EUPDATEDB;;
	-nd|--nodatabase) s false EUPDATEDB;;
	-f|--fetch)       s true  FETCH;;
	-nf|--nofetch)    s false FETCH;;
	-w|--world)       s true  UPWORLD;;
	-nw|--noworld)    s false UPWORLD;;
	-l|--layman)      s true  LAYMAN;;
	-nl|--nolayman)   s false LAYMAN;;
	-x|--debug)       s true  DEBUG;;
	-nx|--nodebug)    s false DEBUG;;
	*)                usage;;
	esac
done

run() {
	echo "+ $*"
	"$@"
}
if ${GS_DEBUG} ; then
	set -x
	run() { "$@" ; }
fi

export NOCOLOR=true

(
id
date

if ${GS_RSYNC} ; then
	# For slow systems, run rsync directly.
	for f in make.globals make.conf ; do
		for d in /etc /etc/portage /usr/share/portage/config ; do
			f="${d}/make.globals"
			[[ -e ${f} ]] && . ${f} && break
		done
	done
	> "${up_log}"
	: ${PORTAGE_RSYNC_OPTS:=-azO --delete --exclude=/distfiles --exclude=/local --exclude=/packages}
	: ${SYNC:=rsync://rsync.gentoo.org/gentoo-portage}
	: ${PORTDIR:=/usr/portage}
	exec rsync ${PORTAGE_RSYNC_OPTS} ${PORTAGE_RSYNC_EXTRA_OPTS} ${SYNC}/ ${PORTDIR}/ >& "${sync_log}"
fi

if ${GS_SYNC} ; then
	run emerge --sync -q
	date
	${GS_EUPDATEDB} && run $(type -P eupdatedb)
	date
	${GS_LAYMAN} && l=$(type -P layman) && run ${l} -S -q
	date
	${GS_FETCH} && run emerge world -Duf
	#date
	#q -qr
fi

date
) >& ${sync_log}

if ${GS_UPWORLD} ; then
	(
	repos=(
		$(portageq repositories_configuration / | awk '$1 == "location" { $1 = $2 = ""; print }')
	)
	bad_pkgs=()
	good_pkgs=()
	for p in `qlist -ICS` ; do
		good=false
		for repo in ${repos[@]} ; do
			if [[ -d ${repo}/${p%:*} ]] ; then
				good=true
				break
			fi
		done

		if ${good} ; then
			good_pkgs+=( ${p} )
		else
			bad_pkgs+=( ${p} )
		fi
	done

	if [[ ${#bad_pkgs[@]} -gt 0 ]] ; then
		echo 'These packages no longer exist:'
		printf '\t%s\n' "${bad_pkgs[@]}"
		echo
	fi
	echo 'emerge -u1v --quiet-build y --keep-going $(awk '\''$2 ~ /\// {print $2}'\'' '${up_log}')'
	emerge -upq --cols \
		$(printf '%s\n' ${good_pkgs[*]} | grep -v '^cross-')
	) >& ${up_log}
	:
fi