#!@@SHELL@@
#
# opkhelper
# src/opkbuild
# Build opkg packages.
#
# Copyright (C) 2012 Patrick "P. J." McDermott
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

. @@LIBDIR@@/messages
. @@LIBDIR@@/locale
. @@LIBDIR@@/changelog

# Environment variables:
export OH_SOURCE=
export OH_SOURCE_VERSION=
export OH_SOURCE_VERSION_UPSTREAM=
export OH_BINARY_VERSION=
export OH_BUILD_ARCH=
export OH_BUILD_ARCH_CPU=
export OH_BUILD_ARCH_KERNEL=
export OH_BUILD_ARCH_LIBS=
export OH_BUILD_PLATFORM=
export OH_BUILD_ARCH_GNU=
export OH_HOST_ARCH=
export OH_HOST_ARCH_CPU=
export OH_HOST_ARCH_KERNEL=
export OH_HOST_ARCH_LIBS=
export OH_HOST_PLATFORM=
export OH_HOST_ARCH_GNU=
export OH_TOOL_PREFIX=
export AR=
export AS=
export CC=
export CPP=
export CXXLD=
export NM=
export OBJCOPY=
export OBJDUMP=
export RANLIB=
export READELF=
export SIZE=
export STRINGS=
export STRIP=

# Constant global parameters:
SOURCE_VERSION_ID_RE='^'
SOURCE_VERSION_ID_RE="${SOURCE_VERSION_ID_RE}"'[0-9a-z.~]+'
SOURCE_VERSION_ID_RE="${SOURCE_VERSION_ID_RE}"'(\+sip[1-9][0-9]*)?'
SOURCE_VERSION_ID_RE="${SOURCE_VERSION_ID_RE}"'(-[1-9][0-9]*)?'
SOURCE_VERSION_ID_RE="${SOURCE_VERSION_ID_RE}"'(\+[a-z0-9]+-[1-9][0-9]*)?'
SOURCE_VERSION_ID_RE="${SOURCE_VERSION_ID_RE}"'$'

# Global parameters:
OPT_BUILD=
OPT_TARGET=
OPT_HOST_ARCH=
OPT_HOST_PLAT=
OPT_CHECK_BUILD_DEPS=
OPT_CLEAN=
OPT_UID0_CMD=

main()
{
	oh_locale_set

	get_options
	if [ "${#}" -ne 0 ]; then
		oh_usage
		exit 1
	fi

	test_uid0_cmd

	find_sanity
	oh_changelog_parse changelog setup_package

	if [ "${OPT_BUILD}" = 'source' -o "${OPT_BUILD}" = 'full' ]; then
		build_source
	fi

	if [ "${OPT_BUILD}" != 'source' ]; then
		"${OPT_CHECK_BUILD_DEPS}" && oh-checkbuilddeps
		setup_build
		print_arch_stats
		if [ -n "${OH_CV_STEP}" ]; then
			"step_${OH_CV_STEP}"
		else
			make_work_area
		fi
	fi
}

get_options()
{
	# Parse and handle command-line options.
	while getopts 'bBASFT:a:P:Ddr:hV' opt; do
		case "${opt}" in
			b)
				if [ -n "${OPT_BUILD}" ]; then
					oh_error "${oh_str_basf_mutex}"
				fi
				OPT_BUILD=binary
				;;
			B)
				if [ -n "${OPT_BUILD}" ]; then
					oh_error "${oh_str_basf_mutex}"
				fi
				OPT_BUILD=binary-arch
				;;
			A)
				if [ -n "${OPT_BUILD}" ]; then
					oh_error "${oh_str_basf_mutex}"
				fi
				OPT_BUILD=binary-indep
				;;
			S)
				if [ -n "${OPT_BUILD}" ]; then
					oh_error "${oh_str_basf_mutex}"
				fi
				OPT_BUILD=source
				;;
			F)
				if [ -n "${OPT_BUILD}" ]; then
					oh_error "${oh_str_basf_mutex}"
				fi
				OPT_BUILD=full
				;;
			T)
				OPT_TARGET="${OPTARG}"
				;;
			a)
				OPT_HOST_ARCH="${OPTARG}"
				;;
			P)
				OPT_HOST_PLAT="${OPTARG}"
				;;
			D)
				OPT_CHECK_BUILD_DEPS=true
				;;
			d)
				OPT_CHECK_BUILD_DEPS=false
				;;
			C)
				OPT_CLEAN=true
				;;
			c)
				OPT_CLEAN=false
				;;
			r)
				OPT_UID0_CMD="${OPTARG}"
				;;
			h)
				oh_help
				exit 0
				;;
			V)
				oh_version
				exit 0
				;;
			?)
				oh_error "${oh_str_bad_opt}" "${opt}"
				exit 1
				;;
		esac
	done
	shift $(($OPTIND - 1))

	# Set default option values.
	[ -z "${OPT_BUILD}" ] && OPT_BUILD=full
	[ -z "${OPT_CHECK_BUILD_DEPS}" ] && OPT_CHECK_BUILD_DEPS=true
	[ -z "${OPT_UID0_CMD}" ] && OPT_UID0_CMD=fakeroot

	# Set default target and cleaning behavior.
	if [ -n "${OPT_TARGET}" ]; then
		[ -z "${OPT_CLEAN}" ] && OPT_CLEAN=false
	else
		if [ "${OPT_BUILD}" = 'full' ]; then
			OPT_TARGET=binary
		else
			OPT_TARGET="${OPT_BUILD}"
		fi
		[ -z "${OPT_CLEAN}" ] && OPT_CLEAN=true
	fi
}

test_uid0_cmd()
{
	# Verify that the UID 0 command works.
	test_uid=$("${OPT_UID_CMD}" id -u)
	if [ "${?}" -ne 0 ]; then
		oh_error "${oh_str_uid0_cmd_not_found}" "${OPT_UID_CMD}"
	fi
	if [ "${test_uid}" -ne 0 ]; then
		oh_error "${oh_str_uid0_cmd_bad_uid}" "${OPT_UID_CMD}"
	fi
}

find_sanity()
{
	oh_info "${oh_str_find_sanity}"

	format="$(cat format 2>/dev/null)"
	if [ "${?}" -ne 0 ]; then
		oh_error "${oh_str_no_format}"
	fi
	if [ "${format}" -ne 0 ]; then
		oh_error "${oh_str_unsupported_format}"
	fi

	# Check for all files immediately required by SPF 2.0.
	[ ! -f 'control' ] && oh_error "${oh_str_no_control}"
	[ ! -x 'config' ] && oh_error "${oh_str_no_config}"
	[ ! -f 'copyright' ] && oh_error "${oh_str_no_copyright}"
	[ ! -f 'changelog' ] && oh_error "${oh_str_no_changelog}"
}

setup_package()
{
	[ -n "${OH_SOURCE}" ] && return
	OH_SOURCE="${OH_CHANGELOG_SOURCE}"
	OH_SOURCE_VERSION="${OH_CHANGELOG_VERSION}"

	# Validate source package version identifier.
	echo "${OH_SOURCE_VERSION}" | grep -E "${SOURCE_VERSION_ID_RE}" \
		>/dev/null 2>&1
	if [ "${?}" -ne 0 ]; then
		oh_error "${oh_str_bad_source_version}" "${OH_SOURCE_VERSION}"
	fi

	OH_SOURCE_VERSION_UPSTREAM="${OH_SOURCE_VERSION:%%-}"
	OH_BINARY_VERSION="${OH_SOURCE_VERSION}"
}

build_source()
{
	# TODO: Build source package.
}

setup_build()
{
	setup_build_arch
	setup_build_flags
	setup_build_platform
	setup_host_arch
	setup_host_platform
	setup_toolchain
}

setup_build_arch()
{
	# TODO: Get build arch from opkg.
	# TODO: Get GNU system type from table.

	IFS=- read OH_BUILD_ARCH_CPU OH_BUILD_ARCH_KERNEL OH_BUILD_ARCH_LIBS <<EOF
${OH_BUILD_ARCH}
EOF
}

setup_build_flags()
{
	# TODO: Don't hardcode path.
	if [ -f "/usr/local/share/opkhelper/buildflags/${OH_HOST_ARCH_CPU}" ]; then
		. /usr/local/share/opkhelper/buildflags/${OH_HOST_ARCH_CPU}
	fi
}

setup_build_platform()
{
	# TODO: Get build platform from opkg.
}

setup_host_arch()
{
	if [ -n "${OPT_HOST_ARCH}" ]; then
		OH_HOST_ARCH="${OPT_HOST_ARCH}"
	else
		OH_HOST_ARCH="${OH_BUILD_ARCH}"
	fi

	IFS=- read OH_HOST_ARCH_CPU OH_HOST_ARCH_KERNEL OH_HOST_ARCH_LIBS <<EOF
${OH_HOST_ARCH}
EOF
}

setup_host_platform()
{
	if [ -n "${OPT_HOST_PLAT}" ]; then
		OH_HOST_PLATFORM="${OPT_HOST_PLAT}"
	else
		OH_HOST_PLATFORM="${OH_BUILD_PLATFORM}"
	fi
}

setup_toolchain()
{
	OH_TOOL_PREFIX="${OH_HOST_ARCH}-"

	# Set toolchain environment variables.
	# NB: This is written for GNU Binutils and GCC and won't work for, e.g., LLVM.
	AR="${OH_TOOL_PREFIX}ar"
	AS="${OH_TOOL_PREFIX}as"
	CC="${OH_TOOL_PREFIX}gcc"
	CPP="${OH_TOOL_PREFIX}cpp"
	CXX="${OH_TOOL_PREFIX}g++"
	LD="${OH_TOOL_PREFIX}ld"
	NM="${OH_TOOL_PREFIX}nm"
	OBJCOPY="${OH_TOOL_PREFIX}objcopy"
	OBJDUMP="${OH_TOOL_PREFIX}objdump"
	RANLIB="${OH_TOOL_PREFIX}ranlib"
	READELF="${OH_TOOL_PREFIX}readelf"
	SIZE="${OH_TOOL_PREFIX}size"
	STRINGS="${OH_TOOL_PREFIX}strings"
	STRIP="${OH_TOOL_PREFIX}strip"
}

print_arch_stats()
{
	oh_info "${oh_str_build_arch_stat_header}"
	oh_info "${oh_str_arch_stat_arch}" "${OH_BUILD_ARCH}"
	oh_info "${oh_str_arch_stat_plat}" "${OH_BUILD_PLATFORM}"
	oh_info "${oh_str_host_arch_stat_header}"
	oh_info "${oh_str_arch_stat_arch}" "${OH_HOST_ARCH}"
	oh_info "${oh_str_arch_stat_plat}" "${OH_HOST_PLATFORM}"
}

make_work_area()
{
	mkdir tmp || oh_error "${oh_str_cant_make_work_area}"
	cd tmp || oh_error "${oh_str_cant_enter_work_area}"

	step_unpack
}

step_unpack()
{
	oh_cv_set step unpack

	oh-unpacksource

	step_patch
}

step_patch()
{
	oh_cv_set step patch

	# TODO: Put this in oh-applypatches.
	applied=false
	if [ -d ../patches ]; then
		# Iterate over patches ordered alphabetically by name.
		for patch in $(ls -1 ../patches | sort); do
			oh_info "${oh_str_applying_patch}" "${patch}"
			patch -N -p 1 -u -d src -i "../../patches/${patch}" || \
				oh_error "${oh_str_cant_apply_patch}" "${patch}"
			applied=true
		done
	fi
	${applied} || oh_info "${oh_str_no_patches}"

	step_config
}

step_config()
{
	oh_cv_set step config

	./config

	step_platconf
}

step_platconf()
{
	oh_cv_set step platconf

	# TODO: Put this in oh-copyconfig.
	if [ -f ../config ]; then
		while read -r src dest; do
			if [ -z "${src}" -o -z "${dest}" ]; then
				oh_error
			fi
			# Make sure the destination directory exists.
			mkdir -p "${dest%/*}" || oh_error
			# Find the config package files.
			# TODO: Don't hardcode path.
			config_dir_base="/usr/share/config/${OH_HOST_PLATFORM}/${OH_SOURCE}"
			if [ -d "${config_dir_base}-${OH_SOURCE_VERSION_UPSTREAM}" ]; then
				src_base="${config_dir_base}-${OH_SOURCE_VERSION_UPSTREAM}"
			elif [ -d "${config_dir_base}" ]; then
				src_base="${config_dir_base}"
			else
				# This shouldn't happen unless the package maintainer neglected
				# to add the config package to the package's Build-Depends
				# field.
				oh_error
			fi
			# Copy the config file(s).
			oh_info
			cp -p "${src_base}/${src}" "${dest}" || oh_error
		done <../config
	fi
	for bin_config in ../*.pkg/config; do
		while read -r src dest; do
			if [ -z "${src}" -o -z "${dest}" ]; then
				oh_error
			fi
			# Make sure the destination directory exists.
			mkdir -p "dest/${dest%/*}" || oh_error
			# Find the config package files.
			# TODO: Don't hardcode path.
			config_dir_base="/usr/share/config/${OH_HOST_PLATFORM}/${OH_SOURCE}"
			if [ -d "${config_dir_base}-${OH_SOURCE_VERSION_UPSTREAM}" ]; then
				src_base="${config_dir_base}-${OH_SOURCE_VERSION_UPSTREAM}"
			elif [ -d "${config_dir_base}" ]; then
				src_base="${config_dir_base}"
			else
				# This shouldn't happen unless the package maintainer neglected
				# to add the config package to the package's Build-Depends
				# field.
				oh_error
			fi
			# Copy the config file(s).
			oh_info
			cp -p "${src_base}/${src}" "dest/${dest}" || oh_error
		done <"${bin_config}"
	done

	step_build
}

step_build()
{
	oh_cv_set step build

	./build "${OPT_TARGET}"

	"${OPT_CLEAN}" && step_clean
}

step_clean()
{
	oh_cv_set step clean

	./config clean

	step_cleanwork
}

step_cleanwork()
{
	oh_cv_clear

	cd ..
	rm -Rf tmp
}

main "${@}"