# Copyright 2022 Gentoo Authors
# Distributed under the terms of the GNU General Public License v2

# @ECLASS: yarn.eclass
# @MAINTAINER:
# Andrew Udvare <audvare@gmail.com>
# @AUTHOR:
# Andrew Udvare <audvare@gmail.com>
# @BLURB: Install a Node-based package offline with Yarn.
# @DESCRIPTION:
# Install a Node-based package offline with Yarn.

case ${EAPI:-0} in
	8) ;;
	*) die "${ECLASS}: EAPI ${EAPI:-0} unsupported." ;;
esac

inherit edo multiprocessing

EXPORT_FUNCTIONS src_unpack src_prepare src_configure src_compile src_install

if [[ -z ${_YARN_ECLASS} ]]; then
	# @ECLASS_VARIABLE: YARN_PKGS
	# @DESCRIPTION:
	# Bash array of Yarn package specifications in format [@SCOPE/]NAME-VERSION.
	# @CODE
	#
	# YARN_PKGS=( @types/type-pkg-1.0.0 )
	#
	# @CODE

	# @ECLASS_VARIABLE: _YARN_DISTFILES
	# @INTERNAL
	# @DESCRIPTION:
	# Array of distfile basenames. The output path for a tarball may be
	# different than the basename taken off the URI.
	_YARN_DISTFILES=()

	WANT_GYP=${WANT_GYP:-0}
	YARN_PRODUCTION=${YARN_PRODUCTION:-1}

	# @FUNCTION: yarn_set_globals
	# @DESCRIPTION:
	# This must be called after defining YARN_PKGS in global scope. This
	# function sets up YARN_SRC_URI which must be added to SRC_URI. If you need
	# to be certain that BDEPEND/RDEPEND/RESTRICT/SLOT is empty, set those
	# after calling this.
	yarn_set_globals() {
		# shellcheck disable=SC2034
		BDEPEND="sys-apps/yarn"
		if [ "${WANT_GYP}" -ne 0 ]; then
			BDEPEND+=" dev-build/node-gyp"
		fi
		# shellcheck disable=SC2034
		RDEPEND="net-libs/nodejs:="
		# shellcheck disable=SC2034
		RESTRICT="strip"
		# shellcheck disable=SC2034
		SLOT="0"
		local -r regex='^(@[a-zA-Z0-9_-]+/)?([a-zA-Z0-9\._-]+)-([0-9]+\.[0-9]+\.[0-9]+.*)'
		local -r newline=$'\n'
		if [[ -z ${YARN_PKGS} ]]; then
			eerror "YARN_PKGS variable is not defined"
			die "Can't generate SRC_URI from empty input"
		fi
		for pkg in "${YARN_PKGS[@]}"; do
			local name version prefix out
			[[ $pkg =~ $regex ]] || die "Could not parse name and version from spec: $pkg"
			scope="${BASH_REMATCH[1]}"
			name="${BASH_REMATCH[2]}"
			version="${BASH_REMATCH[3]}"
			prefix=
			if [ -n "$scope" ]; then
				prefix="-${scope/\//}"
			fi
			out="node${prefix}-${name}-${version}.tgz"
			YARN_SRC_URI+=" https://registry.yarnpkg.com/${scope}${name}/-/${name}-${version}.tgz -> ${out}${newline}"
			_YARN_DISTFILES+=( "$out" )
		done
		_YARN_SET_GLOBALS_CALLED=1
		readonly YARN_PKGS
		readonly YARN_SRC_URI
	}

	# @FUNCTION: yarn_src_unpack
	# @DESCRIPTION:
	# Unpacks normal packages but ignores those ending in .tgz.
	yarn_src_unpack() {
		local archive
		for archive in ${A}; do
			case "${archive}" in
			node-*.tgz) ;;
			*)
				unpack "${archive}"
				;;
			esac
		done
	}

	# @FUNCTION: yarn_src_prepare
	# @DESCRIPTION:
	# Prepares up the offline Yarn package files.
	yarn_src_prepare() {
		if [[ ! ${_YARN_SET_GLOBALS_CALLED} ]]; then
			die "yarn_set_globals must be called in global scope"
		fi
		mkdir "${WORKDIR}/lib" "${WORKDIR}/packages" || die
		local file bn
		echo "${_YARN_DISTFILES[@]}"
		for file in "${_YARN_DISTFILES[@]}"; do
			bn=$(basename "$file")
			ln -s "${DISTDIR}/${file}" "${WORKDIR}/packages/${bn:5}" || die
		done
		default
	}

	# @FUNCTION: yarn_src_configure
	# @DESCRIPTION:
	# Sets up the offline Yarn environment.
	yarn_src_configure() {
		edo yarn config set prefix "${HOME}/.node"
		edo yarn config set yarn-offline-mirror "$(realpath "${WORKDIR}/packages")"
	}

	# @FUNCTION: yarn_src_compile
	# @DESCRIPTION:
	# Using Yarn's offline mode, this function installs the package as it would normally and
	# compiles anything that needs to be.
	yarn_src_compile() {
		cd lib || die
		cp "${YARN_PACKAGE_JSON:-${FILESDIR}/${PN}-package.json}" package.json || die
		cp "${YARN_LOCK:-${FILESDIR}/${PN}-yarn.lock}" yarn.lock || die
		local args=(
			--offline
			--verbose
			--no-progress
			--non-interactive
			--build-from-source
		)
		if [[ "$YARN_PRODUCTION" != 0 ]]; then
			args+=(--production)
		fi
		edo env \
			"npm_config_jobs=$(makeopts_jobs)" \
			npm_config_verbose=true \
			npm_config_release=true \
			"npm_config_nodedir=${EPREFIX}/usr/include/node" \
			yarn install "${args[*]}"
		# Delete known pre-built binaries
		rm -fR \
			node_modules/@serialport/bindings-cpp/prebuilds/{darwin,android,win32,linux-arm}* \
			node_modules/@serialport/bindings-cpp/prebuilds/linux-x64/*musl.node || die
		find . -type d -empty -delete || die
		# Delete files that need compilation and related unused files at
		# runtime as we only want distributed .js files
		find . -type f -iregex '.*\.\(tsx?\|jsx\|map\)' -delete || die
	}

	# @FUNCTION: yarn_src_install
	# @DESCRIPTION:
	# Installs the package into /usr/$(get_libdir)/${PN}/node_modules and installs docs.
	yarn_src_install() {
		find . -type f -iregex '.*/license\(\.\(md\|rtf\|txt\)\)?' -delete || die
		insinto "/usr/$(get_libdir)/${PN}/node_modules"
		doins -r lib/node_modules/*
		einstalldocs
	}
	_YARN_ECLASS=1
fi