#!/bin/sh -e
#
# 2013-2019 Nico Schottelius (nico-cdist at schottelius.org)
# 2020 Dennis Camera (dennis.camera at ssrq-sds-fds.ch)
#
# This file is part of cdist.
#
# cdist 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.
#
# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
#
# Manage system locales using localedef(1).
#

state_is=$(cat "${__object:?}/explorer/state")
state_should=$(cat "${__object:?}/parameter/state")

test "${state_should}" = 'present' -o "${state_should}" = 'absent' || {
	printf 'Invalid state: %s\n' "${state_should}" >&2
	exit 1
}

# NOTE: If state explorer fails (e.g. locale(1) missing), the following check
#       will always fail and let definition/removal run.
if test "${state_is}" = "${state_should}"
then
	exit 0
fi

locale=${__object_id:?}
os=$(cat "${__global:?}/explorer/os")

if expr "${locale}" : '.*/' >/dev/null
then
	printf 'Paths as locales are not supported.\n' >&2
	printf '__object_id is: %s\n' "${locale}" >&2
	exit 1
fi

parse_locale() {
	# This function will split locales into their parts. Locale strings are
	# usually of the form: [language[_territory][.codeset][@modifier]]
	# For simplicity, language and territory are not separated by this function.
	# Old Linux systems were also using "english" or "german" as locale strings.
	# Usage: parse_locale locale_str lang_var codeset_var modifier_var
	eval "${2:?}"="$(expr "$1" : '\([^.@]*\)')"
	eval "${3:?}"="$(expr "$1" : '[^.]*\.\([^@]*\)')"
	eval "${4:?}"="$(expr "$1" : '.*@\(.*\)$')"
}

format_locale() {
	# Usage: format_locale language codeset modifier
	printf '%s' "$1"
	test -z "$2" || printf '.%s' "$2"
	test -z "$3" || printf '@%s' "$3"
	printf '\n'
}

gnu_normalize_codeset() {
	echo "$*" | tr -cd '[:alnum:]' | tr '[:upper:]' '[:lower:]'
}


: "${lang=}" "${codeset=}" "${modifier=}"  # declare variables for shellcheck
parse_locale "${locale}" lang codeset modifier


case ${os}
in
	(alpine|openwrt)
		printf '%s does not support locales.\n' "${os}" >&2
		exit 1
		;;
	(archlinux|debian|devuan|ubuntu|suse|centos|fedora|redhat|scientific)
		# FIXME: The code below only works for glibc-based installations.

		# NOTE: Hardcoded, create a pull request in case it is at another
		#       location for some opther distro.
		# NOTE: locale.alias can be symlinked (e.g. Debian)
		aliasfile='/usr/share/locale/locale.alias'

		case ${state_should}
		in
			(present)
				input=$(format_locale "${lang}" '' "${modifier}")
				cat <<-EOF
				set --
				if test -e '${aliasfile}'
				then
					set -- -A '${aliasfile}'
				fi

				localedef -i '${input}' -f '${codeset}' "\$@" '${locale}'
				EOF
				;;
			(absent)
				localename=$(format_locale "${lang}" "$(gnu_normalize_codeset "${codeset}")" "${modifier}")
				printf "localedef --delete-from-archive '%s'\n" "${localename}"
				;;
		esac
		;;
	(freebsd)
		case ${state_should}
		in
			(present)
				if expr "$(grep -oe '^[0-9]*' "${__global:?}/explorer/os_version")" '>=' 11 >/dev/null
				then
					# localedef(1) is available with FreeBSD >= 11
					printf "localedef -i '%s' -f '%s' '%s'\n" "${input}" "${codeset}" "${locale}"
				else
					printf 'localedef(1) was added to FreeBSD starting with version 11.\n' >&2
					printf 'Please upgrade your FreeBSD installation to use %s.\n' "${__type##*/}" >&2
					exit 1
				fi
				;;
			(absent)
				printf "rm -R '/usr/share/locale/%s'\n" "${locale}"
				;;
		esac
		;;
	(netbsd|openbsd)
		# NetBSD/OpenBSD are missing localedef(1).
		# We also do not delete defined locales because they can't be recreated.
		echo "${os} is lacking localedef(1). Locale management unavailable." >&2
		exit 1
		;;
	(*)
		echo "Your operating system (${os}) is currently not supported by this type (${__type##*/})." >&2
		echo "Please contribute an implementation for it if you can." >&2
		exit 1
		;;
esac