# Interface for retrieving source and binary package metadata
#
# Copyright (C) 2012, 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_package_dir=
_ob_package_format=
_ob_binary_packages=
_ob_got_binary_packages=false
_ob_source_parameters=
_ob_binary_parameters=

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

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

	return 0
}

## @brief Initialize libopkbuild for a source package
## @details \fBob_init_package\fP() detects the version of and parses all
##          metadata of a source package.  This function must be called before
##          any other functions that operate on package metadata.
## @operand dir req The root directory of the source package.
## @return Returns 0 on success or 1 if the source package version can't be
##         detected or if the metadata can't be parsed.
## @stderr Prints error or warning messages on detection or parsing errors.
## @pure no This function sets internal global variables.
ob_init_package()
{
	local dir="${1}"
	shift 1 || _ob_abort

	_ob_package_dir="$(cd -- "${dir}" && pwd)"

	if [ -r "${_ob_package_dir}/format" ]; then
		case "$(cat -- "${_ob_package_dir}/format")" in
			2.0)
				_ob_package_format='2'
				;;
		esac
	fi

	if [ -z "${_ob_package_format}" ]; then
		_ob_error_msg 'unable_to_detect_package_format'
		return 1
	fi

	_ob_binary_packages=

	_ob_package_do 'parse_package_metadata' || return ${?}

	return 0
}

## @brief Get a list of binary packages
## @details \fBob_get_binary_packages\fP() finds a source package's binary
##          packages, optionally filtering for packages that build for a certain
##          host architecture and/or platform.
## @option -a host_arch The architecture by which to filter binary packages.
## @option -a host_plat The platform by which to filter binary packages.
## @return Returns 0 on success.
## @stdout Prints the resulting list of binary packages.
## @stderr Prints warning messages on invalid binary package names and duplicate
##         "clean" binary package names.
## @pure maybe This function caches a list of all binary packages to an internal
##             global variable to save time and avoid repeating warning messages
##             on subsequent invocations.  It should therefore first be called
##             outside a subshell, though this is not required.
ob_get_binary_packages()
{
	local opt=
	local host_arch=
	local host_plat=
	local pkg=
	local pkgs_clean=
	local pkg_clean=
	local pkgs=

	OPTIND=1
	while getopts 'a:p:' opt; do
		case "${opt}" in
			a)
				host_arch="${OPTARG}"
				;;
			p)
				host_plat="${OPTARG}"
				;;
			?)
				_ob_abort
				;;
		esac
	done
	shift $((${OPTIND} - 1))

	if ! ${_ob_got_binary_packages}; then

		_ob_package_do 'get_binary_packages'

		pkgs_clean=' '

		for pkg in ${_ob_binary_packages}; do

			# Validate the name.
			if ! ob_validate_binary_name "${pkg}"; then
				_ob_warn_msg 'bad_binary_name' "${pkg}"
				continue
			fi

			# Make sure the "clean" name is unique.
			pkg_clean="$(printf '%s' "${pkg}" | tr 'a-z' 'A-Z' | \
				tr -C 'A-Z0-9' '_')"
			case "${pkgs_clean}" in *" ${pkg_clean} "*)
				_ob_warn_msg 'duplicate_clean_binary_name' \
					"${pkg_clean}"
				continue
			esac
			pkgs_clean="${pkgs_clean}${pkg_clean} "

			_ob_binary_packages="${_ob_binary_packages} ${pkgs}"

		done

		_ob_got_binary_packages=true

	fi

	pkgs=''

	for pkg in ${_ob_binary_packages}; do
		if [ -n "${host_arch}" ] && ! ob_arch_is_concerned \
				"${host_arch}" "$(ob_get_binary_parameter \
				"${pkg}" 'Architecture')"; then
			continue
		fi
		if [ -n "${host_plat}" ] && ! ob_plat_is_concerned \
				"${host_plat}" "$(ob_get_binary_parameter \
				"${pkg}" 'Platform')"; then
			continue
		fi
		pkgs="${pkgs} ${pkg}"
	done

	printf '%s ' ${pkgs}

	return 0
}

## @brief Get a source package field value
## @details \fBob_get_source_parameter\fP() gets the value of a source package
##          field.
## @operand name req The name of the field.
## @return Returns 0 on success or 1 if \fIname\fP is invalid.
## @stdout Prints the source package field value.
## @pure yes This function has no side effects.
ob_get_source_parameter()
{
	local name="${1}"
	shift 1 || _ob_abort

	# Convert field name to uppercase and validate.
	case "${name}" in *[!A-Za-z0-9-]* | '')
		return 1
	esac
	name="$(tr 'a-z-' 'A-Z_' <<-EOF
		${name}
		EOF
		)"

	# TODO: Return error on no such field?
	eval "printf '%s' \"\${_OB_SRCFIELD_${name}-}\""

	return 0
}

## @brief Get a binary package field value
## @details \fBob_get_binary_parameter\fP() gets the value of a binary package
##          field.
## @operand package req The name of the binary package.
## @operand name    req The name of the field.
## @return Returns 0 on success or 1 if \fIname\fP is invalid.
## @stdout Prints the binary package field value.
## @pure yes This function has no side effects.
ob_get_binary_parameter()
{
	local package="${1}"
	local name="${2}"
	shift 2 || _ob_abort

	if ! ob_validate_binary_name "${package}"; then
		return 1
	fi

	# Convert package name to its uppercase "clean" form.
	package="$(printf '%s' "${package}" | tr 'a-z' 'A-Z' | \
		tr -C 'A-Z0-9' '_')"

	# Convert field name to uppercase and validate.
	case "${name}" in *[!A-Za-z0-9-]* | '')
		return 1
	esac
	name="$(tr 'a-z-' 'A-Z_' <<-EOF
		${name}
		EOF
		)"

	# TODO: Return error on no such field?
	eval "printf '%s' \"\${_OB_BINFIELD_${package}_${name}-}\""

	return 0
}

## @brief Get the documentation-providing binary package
## @details \fBob_get_doc_package\fP() gets the name of the binary package that
##          will provide documentation files about the source package.
## @return Returns 0 on success or 1 if no or multiple packages are found to
##         provide documentation files.
## @stdout Prints the documentation-providing binary package name.
## @pure yes This function has no side effects.
ob_get_doc_package()
{
	_ob_package_do 'get_doc_package' || return ${?}

	return 0
}

## @brief Get the source package documentation files table
## @details \fBob_get_doc_files\fP() gets the table of source package
##          documentation files.  The table consists of lines of space-separated
##          source (relative to the build work area) and destination (relative
##          to the source package documentation directory) file paths.
## @return Returns 0 on success.
## @stdout Prints the source package documentation files table.
## @pure yes This function has no side effects.
ob_get_doc_files()
{
	_ob_package_do 'get_doc_files' || return ${?}

	return 0
}

## @brief Set package substitution variables
## @details \fBob_set_package_substvars\fP() sets any substitution variables
##          defined by a source package, as well as any standard substitution
##          variables defined by the source package format, for later use by
##          \fBob_substvars\fP(3).
## @operand pkg req The binary package for which to set substitution variables.
## @return Returns 0 on success.
## @stderr Prints error messages on parse errors.
## @pure no This function sets internal global variables.
ob_set_package_substvars()
{
	local pkg="${1}"
	shift 1 || _ob_abort

	_ob_package_do 'set_package_substvars' "${pkg}" || return ${?}

	return 0
}

_ob_set_binary_packages()
{
	local packages="${1}"
	shift 1 || _ob_abort

	_ob_binary_packages="${packages}"

	return 0
}

_ob_set_source_parameter()
{
	local name="${1}"
	local value="${2}"
	shift 2 || _ob_abort

	# Convert field name to uppercase and validate.
	case "${name}" in *[!A-Za-z0-9-]* | '')
		return 1
	esac
	name="$(tr 'a-z-' 'A-Z_' <<-EOF
		${name}
		EOF
		)"

	_ob_source_parameters="${_ob_source_parameters} ${name}"

	eval "_OB_SRCFIELD_${name}=\"\${value}\""

	return 0
}

_ob_set_binary_parameter()
{
	local package="${1}"
	local name="${2}"
	local value="${3}"
	shift 3 || _ob_abort

	if ! ob_validate_binary_name "${package}"; then
		return 1
	fi

	# Convert package name to its uppercase "clean" form.
	package="$(printf '%s' "${package}" | tr 'a-z' 'A-Z' | \
		tr -C 'A-Z0-9' '_')"

	# Convert field name to uppercase and validate.
	case "${name}" in *[!A-Za-z0-9-]* | '')
		return 1
	esac
	name="$(tr 'a-z-' 'A-Z_' <<-EOF
		${name}
		EOF
		)"

	case " ${_ob_binary_parameters} " in
		*" ${name} "*)
			;;
		*)
			_ob_binary_parameters="${_ob_binary_parameters} ${name}"
			;;
	esac

	eval "_OB_BINFIELD_${package}_${name}=\"\${value}\""

	return 0
}