# Functions for parsing and validating package metadata
#
# Copyright (C) 2012, 2014, 2018, 2019 Patrick McDermott
#
# This file is part of opkbuild.
#
# opkbuild 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.
#
# opkbuild 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 opkbuild.  If not, see <http://www.gnu.org/licenses/>.

_ob_metadata_do()
{
	local func="${1}"
	shift 1 || _ob_abort

	"_ob_${func}" "${@}" || return ${?}

	return 0
}

## @brief Validate a source package name
## @details \fBob_validate_source_name\fP() validates a source package name
##          against the rules of the metadata plugin selected at libopkbuild's
##          build time.
## @operand name req The source package name to validate.
## @return Returns 0 if valid or 1 if invalid.
## @pure yes This function has no side effects.
ob_validate_source_name()
{
	local name="${1}"
	shift 1 || _ob_abort

	_ob_metadata_do 'validate_source_name' "${name}" || return ${?}

	return 0
}

## @brief Validate a binary package name
## @details \fBob_validate_binary_name\fP() validates a binary package name
##          against the rules of the metadata plugin selected at libopkbuild's
##          build time.
## @operand name req The binary package name to validate.
## @return Returns 0 if valid or 1 if invalid.
## @pure yes This function has no side effects.
ob_validate_binary_name()
{
	local name="${1}"
	shift 1 || _ob_abort

	_ob_metadata_do 'validate_binary_name' "${name}" || return ${?}

	return 0
}

## @brief Parse a source package version
## @details \fBob_parse_version\fP() validates and parses a source package
##          version identifier using the metadata plugin selected at
##          libopkbuild's build time.  Parsing is limited to extracting the
##          entire upstream version and distribution revision.
## @option -u upstreamver_var The name of the variable in which to store the
##                            upstream version.
## @option -d distrev_var     The name of the variable in which to store the
##                            distribution revision.
## @operand version req The version to validate and parse.
## @return Returns 0 on success or 1 on invalid \fIversion\fP.
## @pure maybe This function has side effects when used with either or both of
##             the \fB-u\fP and \fB-d\fP options.  Without these options, this
##             function only validates a version identifier.  The purpose of
##             this function is mainly to extract version components using these
##             options, so in practice this function is generally not
##             subshell-safe.
ob_parse_version()
{
	local opt=
	local upstreamver_var=
	local distrev_var=
	local version=

	OPTIND=1
	while getopts 'u:d:' opt; do
		case "${opt}" in
			u)
				upstreamver_var="${OPTARG}"
				if ! _ob_validate_var_name "${upstreamver_var}"
				then
					_ob_abort
				fi
				;;
			d)
				distrev_var="${OPTARG}"
				if ! _ob_validate_var_name "${distrev_var}"
				then
					_ob_abort
				fi
				;;
			?)
				_ob_abort
				;;
		esac
	done
	shift $((${OPTIND} - 1))

	version="${1}"
	shift 1 || _ob_abort

	if ! _ob_metadata_do 'validate_version' "${version}"; then
		return 1
	fi

	if [ -n "${upstreamver_var}" ]; then
		eval "${upstreamver_var}=\"\$(_ob_metadata_do 'get_upstreamver' \
			"${version}")\""
	fi
	if [ -n "${distrev_var}" ]; then
		eval "${distrev_var}=\"\$(_ob_metadata_do 'get_distrev' \
			"${version}")\""
	fi

	return 0
}

## @brief Get the running system's architecture
## @details \fBob_get_system_arch\fP() gets the architecture of the build
##          (running) system using the metadata plugin selected at libopkbuild's
##          build time.
## @return Returns 0 on success or 1 if the system's architecture cannot be
##         determined.
## @stdout Prints the system's architecture.
## @pure yes This function has no side effects.
ob_get_system_arch()
{
	_ob_metadata_do 'get_system_arch' || return ${?}

	return 0
}

## @brief Get the running system's platform
## @details \fBob_get_system_plat\fP() gets the platform of the build (running)
##          system using the metadata plugin selected at libopkbuild's build
##          time.
## @return Returns 0 on success or 1 if the system's platform cannot be
##         determined.
## @stdout Prints the system's platform.
## @pure yes This function has no side effects.
ob_get_system_plat()
{
	_ob_metadata_do 'get_system_plat' || return ${?}

	return 0
}

_ob_match_arch()
{
	local match_arch="${1}"
	local field_arch="${2}"
	shift 2 || _ob_abort
	local match_arch_rest=
	local field_arch_rest=
	local match_arch_part=
	local field_arch_part=

	# "foo-bar-baz" == "any"
	if [ x"${field_arch}" = x'any' ]; then
		return 0
	fi

	# "foo-bar-baz" == "foo-any-any"
	match_arch_rest="${match_arch}"
	field_arch_rest="${field_arch}"
	while [ -n "${match_arch_rest}" ] && [ -n "${field_arch_rest}" ]; do
		IFS='-' read match_arch_part match_arch_rest <<-EOF
			${match_arch_rest}
			EOF
		IFS='-' read field_arch_part field_arch_rest <<-EOF
			${field_arch_rest}
			EOF
		case "${field_arch_part}" in
			"${match_arch_part}" | 'any') ;;
			*) return 1;;  # Failed match
		esac
	done

	return 0
}

## @brief Match a host architecture against an architecture field
## @details \fBob_arch_is_concerned\fP() checks whether a host architecture
##          matches an architecture field.  The host architecture may be either
##          a specific distribution architecture or "all".  The architecture
##          field may be either a space-separated list of either "any" or
##          specific distribution architectures, any of which can be negated
##          with a prefix of "!", or "all".
## @operand host_arch req The host architecture to match.
## @operand arches    req The architecture field against which to match.
## @return Returns 0 if \fIhost_arch\fP matches \fIarches\fP, or 0 if not.
## @pure yes This function has no side effects.
ob_arch_is_concerned()
{
	local host_arch="${1}"
	local arches="${2}"
	shift 2 || _ob_abort
	local arch=
	local not_arch=
	local seen_arch=

	if [ x"${arches}" = x'' ]; then
		return 0
	elif [ x"${host_arch}" = x'all' ]; then
		if [ x"${arches}" = x'all' ]; then
			return 0
		else
			return 1
		fi
	else
		seen_arch=1
		for arch in ${arches}; do
			not_arch="${arch#!}"
			if [ x"${not_arch}" != x"${arch}" ]; then
				if _ob_match_arch "${host_arch}" "${not_arch}"
				then
					seen_arch=1
					break
				else
					seen_arch=0
				fi
			elif _ob_match_arch "${host_arch}" "${arch}"; then
				seen_arch=0
				break
			fi
		done
		return ${seen_arch}
	fi
}

_ob_match_plat()
{
	local match_plat="${1}"
	local field_plat="${2}"
	shift 2 || _ob_abort

	if [ x"${field_plat}" = x'any' ]; then
		return 0
	fi
	if [ x"${field_plat}" = x"${match_plat}" ]; then
		return 0
	fi

	return 1
}

## @brief Match a host platform against a platform field
## @details \fBob_plat_is_concerned\fP() checks whether a host platform matches
##          a platform field.  The host platform may be either a specific
##          distribution platform or "all".  The platform field may be either a
##          space-separated list of either "any" or specific distribution
##          platforms, any of which can be negated with a prefix of "!", or
##          "all".
## @operand host_plat req The host platform to match.
## @operand plats     req The platform field against which to match.
## @return Returns 0 if \fIhost_plat\fP matches \fIplats\fP, or 0 if not.
## @pure yes This function has no side effects.
ob_plat_is_concerned()
{
	local host_plat="${1}"
	local plats="${2}"
	shift 2 || _ob_abort
	local plat=
	local not_plat=
	local seen_plat=

	if [ x"${plats}" = x'' ]; then
		return 0
	elif [ x"${host_plat}" = x'all' ]; then
		if [ x"${plats}" = x'all' ]; then
			return 0
		else
			return 1
		fi
	else
		seen_plat=1
		for plat in ${plats}; do
			not_plat="${plat#!}"
			if [ x"${not_plat}" != x"${plat}" ]; then
				if _ob_match_plat "${host_plat}" "${not_plat}"
				then
					seen_plat=1
					break
				else
					seen_plat=0
				fi
			elif _ob_match_plat "${host_plat}" "${plat}"; then
				seen_plat=0
				break
			fi
		done
		return ${seen_plat}
	fi
}

## @brief Get a system path
## @details \fBob_get_system_path\fP() gets a system path consisting of
##          \fIargs\fP formatted, by the metadata plugin selected at
##          libopkbuild's build time, according to a path format identified by
##          \fIpath_id\fP.  The arguments for a \fIpath_id\fP of either
##          \fBpackage-source\fP or \fBpackage-docs\fP are \fIsource\fP and
##          \fIversion\fP.  For \fBbuildflags\fP the argument is \fI arch\fP. 
##          For \fBplatconf\fP they can be either only \fIplat\fP or all of
##          \fIsource\fP, \fIversion\fP, and \fIplat\fP; the latter form is
##          deprecated.  For \fBbuildflags\fP and \fBplatconf\fP, the system
##          path will be under the value of the \fIOB_TEST_DATADIR\fP
##          environment variable, if set and not null; this is intended for use
##          in testing programs that call this function.
## @operand path_id req One of \fBpackage-source\fP, \fBpackage-docs\fP,
##                      \fBbuildflags\fP, or \fBplatconf\fP.
## @operand args    req Additional arguments specific to each \fIpath_id\fP.
## @return Returns 0 on success.
## @stdout Prints the requested path with \fIargs\fP.
## @pure yes This function has no side effects.
ob_get_system_path()
{
	local path_id="${1}"
	shift 1 || _ob_abort

	_ob_metadata_do 'get_system_path' "${path_id}" "${@}" || return ${?}

	return 0
}