# Copyright 2017 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2

# @ECLASS: meson.eclass
# @MAINTAINER:
# William Hubbs <williamh@gentoo.org>
# @BLURB: common ebuild functions for meson-based packages
# @DESCRIPTION:
# This eclass contains the default phase functions for packages which
# use the meson build system.
#
# @EXAMPLE:
# Typical ebuild using meson.eclass:
#
# @CODE
# EAPI=6
#
# inherit meson
#
# ...
#
# src_configure() {
# 	local emesonargs=(
# 		-Dqt4=$(usex qt4 true false)
# 		-Dthreads=$(usex threads true false)
# 		-Dtiff=$(usex tiff true false)
# 	)
# 	meson_src_configure
# }
#
# ...
#
# @CODE

case ${EAPI:-0} in
	6) ;;
	*) die "EAPI=${EAPI} is not supported" ;;
esac

if [[ -z ${_MESON_ECLASS} ]]; then

# FIXME: We will need to inherit toolchain-funcs as well to support crossdev.
inherit ninja-utils

fi

EXPORT_FUNCTIONS src_configure src_compile src_test src_install

if [[ -z ${_MESON_ECLASS} ]]; then
_MESON_ECLASS=1

DEPEND=">=dev-util/meson-0.39.1
	>=dev-util/ninja-1.7.2"

# @ECLASS-VARIABLE: BUILD_DIR
# @DEFAULT_UNSET
# @DESCRIPTION:
# Build directory, location where all generated files should be placed.
# If this isn't set, it defaults to ${WORKDIR}/${P}-build.

# @ECLASS-VARIABLE: EMESON_SOURCE
# @DEFAULT_UNSET
# @DESCRIPTION:
# The location of the source files for the project; this is the source
# directory to pass to meson.
# If this isn't set, it defaults to ${S}

# @VARIABLE: emesonargs
# @DEFAULT_UNSET
# @DESCRIPTION:
# Optional meson arguments as Bash array; this should be defined before
# calling meson_src_configure.

# Create a cross file for meson
# fixme: This function should write a cross file as described at the
# following url.
# http://mesonbuild.com/Cross-compilation.html
# _meson_create_cross_file() {
#	touch "${T}"/meson.crossfile
# }

# @FUNCTION: meson_src_configure
# @DESCRIPTION:
# This is the meson_src_configure function
meson_src_configure() {
	debug-print-function ${FUNCNAME} "$@"

	# Common args
	local mesonargs=(
		--buildtype plain
		--libdir "$(get_libdir)"
		--localstatedir "${EPREFIX}/var/lib"
		--prefix "${EPREFIX}/usr"
		--sysconfdir "${EPREFIX}/etc"
		)

# fixme: uncomment this for crossdev support
#	if tc-is-cross-compiler; then
#		_meson_create_cross_file || die "unable to write meson cross file"
#		mesonargs+=(
#			--cross-file "${T}"/meson.crossfile
#		)
#	fi

	# Append additional arguments from ebuild
	mesonargs+=("${emesonargs[@]}")

	BUILD_DIR="${BUILD_DIR:-${WORKDIR}/${P}-build}"
	set -- meson "${mesonargs[@]}" "$@" \
		"${EMESON_SOURCE:-${S}}" "${BUILD_DIR}"
	echo "$@"
	"$@" || die
}

# @FUNCTION: meson_src_compile
# @DESCRIPTION:
# This is the meson_src_compile function.
meson_src_compile() {
	debug-print-function ${FUNCNAME} "$@"

	eninja -C "${BUILD_DIR}"
}

# @FUNCTION: meson_src_test
# @DESCRIPTION:
# This is the meson_src_test function.
meson_src_test() {
	debug-print-function ${FUNCNAME} "$@"

	eninja -C "${BUILD_DIR}" test
}

# @FUNCTION: meson_src_install
# @DESCRIPTION:
# This is the meson_src_install function.
meson_src_install() {
	debug-print-function ${FUNCNAME} "$@"

	DESTDIR="${D}" eninja -C "${BUILD_DIR}" install
	einstalldocs
}

fi