# -*-eselect-*-  vim: ft=eselect
# Copyright 2014-2020 Gentoo Authors
# Distributed under the terms of the GNU General Public License v2

inherit config multilib

DESCRIPTION="Manage lua symlinks"
MAINTAINER="mva@gentoo.org"

HEADER_FILES="lauxlib.h luaconf.h lua.h lua.hpp lualib.h"

remove_symlinks() {
	rm -f "${EROOT}"/usr/bin/{lua,luac} &>/dev/null 
	rm -f "${EROOT}"/usr/share/man/man1/lua{,c}.1{,.*} &>/dev/null
	# Possible leftovers from earlier versions
	for dir in $(get_libdirs) ; do
		rm -f "${EROOT}"${dir}/liblua.so &>/dev/null && \
		rm -f "${EROOT}"${dir}/pkgconfig/lua.pc &>/dev/null
	done
	for f in $HEADER_FILES ; do
		rm -f "${EROOT}"/usr/include/${f}
	done
}

_dup() {
	dirname ${1}/.
}

set_symlinks() {
	local ver=${1#lua}
	local bin_prefix="${EROOT}/usr/bin"
	ln -s lua${ver} $(_dup "${bin_prefix}"/lua)
	if [[ -f "${bin_prefix}"/luac${ver} ]]; then
		ln -s luac${ver} $(_dup "${bin_prefix}"/luac)
	fi
	for manpage in "${EROOT}"/usr/share/man/man1/lua{,c}${ver}.1.* ; do
		test -f ${manpage} &&
		ln -s $(basename "${manpage}") $(_dup "${manpage//${ver}}")
	done
}

get_libdirs() {
	local dir libdirs
	for dir in $(list_libdirs); do
		[[ -L ${EROOT}/usr/${dir} ]] && continue
		ls "${EROOT}"/usr/${dir}/liblua*.* > /dev/null 2>&1 || continue
 
		libdirs+=' '/usr/${dir}
	done
	echo ${libdirs:-/usr/lib}
}

find_targets() {
	local dirs
	local prefix="${EROOT}/usr/bin/"
	for f in ${prefix}lua{5,jit-2}.* ; do
		[[ -f "${f}" ]] && dirs="${dirs} ${f##$prefix}"
	done
	echo $dirs
}

resolve_target() {
	local targets=( $(find_targets) )
	if is_number $1; then
		[[ $1 -le ${#targets[@]} && $1 -gt 0 ]] && echo "${targets[ $(( $1 - 1 )) ]}"
	elif has $1 ${targets[@]}; then
		echo $1
	fi
}

get_active_version() {
	readlink -e "${EROOT}"/usr/bin/lua | sed -ne "s:.*/usr/bin/\([\w.-]*\):\1:p"
}

## Actual actions

## set action

describe_set() {
	echo "Sets the current version of lua"
}

describe_set_parameters() {
	echo '[--if-unset] <target>'
}

describe_set_options() {
	echo '--if-unset:  Do not replace currently selected implementation'
	echo 'target:      Target name or number (from "list" action)'
}

do_set() {
	if [ "${1}" == "--if-unset" ]; then
		if [[ -n "$(get_active_version)" ]]; then
			return
		fi
		shift
	fi

	local target=$(resolve_target $1)
	if [[ -z "${target}" ]]; then
		die -q "You need to specify a version"
	fi
	remove_symlinks
	set_symlinks $target
}

## List action

describe_list() {
	echo 'Lists available lua versions'
}

do_list() {
	local targets
	local a
	targets=( $(find_targets) )
	a=$(get_active_version)
	for (( i = 0; i < ${#targets[@]}; i++ )) ; do
		[[ $a == ${targets[i]} ]] && targets[i]=$(highlight_marker "${targets[i]}")
	done
	write_numbered_list -m '(none found)' "${targets[@]}"
}

## Show action

describe_show() {
	echo 'Show the active lua version'
}

do_show() {
	get_active_version
}