#!@@SHELL@@
#
# opkhelper
# lib/control
# Functions for parsing control files.
#
# Copyright (C) 2012 Patrick "P. J." McDermott
#
# This program 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.
#
# This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

[ -n "${_OH_CONTROL_SH}" ] && return 0
_OH_CONTROL_SH=true

. @@LIBDIR@@/messages
. @@LIBDIR@@/locale
. @@LIBDIR@@/util

# Constant global parameters:
OH_CONTROL_SOURCE_FIELDS_REQUIRED='Maintainer'
OH_CONTROL_SOURCE_FIELDS_OPTIONAL='Build-Depends Homepage'
OH_CONTROL_BINARY_FIELDS_REQUIRED='Architecture Platform Priority Description'
OH_CONTROL_BINARY_FIELDS_OPTIONAL='Essential Depends Recommends Suggests '\
'Pre-Depends Conflicts Provides Replaces'
OH_CONTROL_SOURCE_FIELD_MAINTAINER=
OH_CONTROL_SOURCE_FIELD_BUILD_DEPENDS=
OH_CONTROL_SOURCE_FIELD_HOMEPAGE=
OH_CONTROL_BINARY_FIELD_ARCHITECTURE=
OH_CONTROL_BINARY_FIELD_PLATFORM=
OH_CONTROL_BINARY_FIELD_PRIORITY=
OH_CONTROL_BINARY_FIELD_DESCRIPTION=
OH_CONTROL_BINARY_FIELD_ESSENTIAL=
OH_CONTROL_BINARY_FIELD_DEPENDS=
OH_CONTROL_BINARY_FIELD_RECOMMENDS=
OH_CONTROL_BINARY_FIELD_SUGGESTS=
OH_CONTROL_BINARY_FIELD_PRE_DEPENDS=
OH_CONTROL_BINARY_FIELD_CONFLICTS=
OH_CONTROL_BINARY_FIELD_PROVIDES=
OH_CONTROL_BINARY_FIELD_REPLACES=

oh_control_parse_source()
{
	_control_parse "${OH_SOURCE_DIR}/control" 'SOURCE'
}

oh_control_parse_binary()
{
	_control_parse "${OH_SOURCE_DIR}/${1}.pkg/control" 'BINARY'
}

oh_control_gen_source()
{
	_old_package="${OH_CONTROL_BINARY_FIELD_PACKAGE}"
	_old_version="${OH_BINARY_VERSION}"
	_old_architecture="${OH_CONTROL_BINARY_FIELD_ARCHITECTURE}"
	_old_recommends="${OH_CONTROL_BINARY_FIELD_RECOMMENDS}"
	_old_description="${OH_CONTROL_BINARY_FIELD_DESCRIPTION}"

	OH_CONTROL_BINARY_FIELD_PACKAGE="src:${OH_SOURCE}"
	OH_BINARY_VERSION="${OH_SOURCE_VERSION}"
	OH_CONTROL_BINARY_FIELD_ARCHITECTURE='all'
	OH_CONTROL_BINARY_FIELD_RECOMMENDS="${OH_CONTROL_SOURCE_FIELD_BUILD_DEPENDS}"
	OH_CONTROL_BINARY_FIELD_DESCRIPTION="${OH_SOURCE} source package"

	_control_gen 'SOURCE' \
		"src:${OH_SOURCE}.control/control" "src:${OH_SOURCE}.data"

	OH_CONTROL_BINARY_FIELD_PACKAGE="${_old_package}"
	OH_BINARY_VERSION="${_old_version}"
	OH_CONTROL_BINARY_FIELD_ARCHITECTURE="${_old_architecture}"
	OH_CONTROL_BINARY_FIELD_RECOMMENDS="${_old_recommends}"
	OH_CONTROL_BINARY_FIELD_DESCRIPTION="${_old_description}"
}

oh_control_gen_binary()
{
	_control_gen 'BINARY' \
		"${1}.control/control" "${1}.data"
}

_control_parse()
{
	_control="${1}"
	_type="${2}"
	_req=" $(eval echo \$\{OH_CONTROL_"${_type}"_FIELDS_REQUIRED) "
	_opt=" $(eval echo \$\{OH_CONTROL_"${_type}"_FIELDS_OPTIONAL) "
	_all="${_req}${_opt}"
	_got=' '

	# Initialize fields.
	for _param in ${_all}; do
		eval "${_param}="
	done
	_param=

	_line_nr=0

	while read -r _line; do
		_line_nr=$(($_line_nr + 1))
		if [ "${_line# }" = "${_line}" ]; then
			# "Name: Value" line.
			_name="${_line%%:*}"
			_value="${_line#*:}"
			if [ -z "${_name}" -o "${_name}" = "${_line}" \
				-o -z "${_value}" ]; then
				# Badly formatted control field.
				_control_parse_error "${_control}" "${_line_nr}" \
					"${oh_str_control_bad_nv}"
				continue
			fi
			if [ "${_all% ${_name} }" = "${_all}" ]; then
				# Unknown field.
				_control_parse_error "${_control}" "${_line_nr}" \
					"${oh_str_control_unknown_field}" \
					"${_control}" "${_name}"
			else
				# Remove field from list of required fields.
				_req="$(echo "${_req}" | sed "s/${_name}//")"
			fi
			if [ "${_got% ${_name} }" != "${_got}" ]; then
				# Duplicate field.
				_control_parse_error "${_control}" "${_line_nr}" \
					"${oh_str_control_duplicate_field}" \
					"${_control}" "${_field}"
			else
				_got="${_got}${_field} "
			fi
			_param="OH_CONTROL_${_type}_FIELD_$(echo "${_name}" | \
				LC_CTYPE=C tr '[:lower:]-' '[:upper:]_')"
			eval "${_param}=\"${_value}\""
		else
			# Continuation line.
			if [ -z "${_param}" ]; then
				# Expecting a "Name: Value" line.
				_control_parse_error "${_control}" "${_line_nr}" \
					"${oh_str_control_found_continuation}"
				continue
			fi
			_value="${_line# }"
			eval "${_param}=\"${_param}
${_value}\""
		fi
	done <"${_control}"

	_req="${_req## }"
	_req="${_req%% }"
	if [ -n "${_req}" ]; then
		# Missing required control fields.
		_control_parse_error "${_control}" 0 \
			"${oh_str_control_missing_fields}" \
			"$(echo "${_req}" | sed 's/  / /g' | sed 's/ /,/g')"
	fi
}

_control_parse_error()
{
	_file="${1}"
	_line_nr="${2}"
	_error="${3}"
	shift 3

	if [ "${_line_nr}" -eq 0 ]; then
		_file_info=$(printf '%20s:' "${_file}" "${_line_nr}")
	else
		_file_info=$(printf '%20s(l%d):' "${_file}" "${_line_nr}")
	fi
	oh_warn "${_file_info} ${_error}" "${@}"
}

_control_gen()
{
	_type="${1}"
	_control="${2}"
	_data="${2}"

	# TODO: Handle platforms and architectures like "any" and "any-linux-any".

	# Calculate installed size.
	# Don't use du, since that considers the allocated size of files, symbolic
	# links, and directories (i.e. actual file sizes plus the filesystem
	# overhead on the build system).
	# See the following for more information:
	#   <http://pubs.opengroup.org/onlinepubs/9699919799/utilities/du.html>
	#   <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=630533>
	#   <https://www.gnu.org/software/coreutils/manual/html_node/du-invocation.html>
	_sizes="$(find "${_data}" -type f -exec wc -c '{}' ';' | cut -d ' ' -f 1)"
	_inst_size=0
	for _size in ${_sizes}; do
		_inst_size=$(($_inst_size + $_size))
	done
	# Convert bytes to kibibytes and round up.
	# Note: There is an inconsistency between the Debian Policy Manual and opkg
	# in the units of this field.  Debian Policy defines this field in units of
	# kibibytes:
	#   The disk space is given as the integer value of the estimated installed
	#   size in bytes, divided by 1024 and rounded up.
	# However, opkg apparently attempts to convert this value from bytes to
	# kibibytes in its determination of whether the package's data will fit on
	# the system:
	#   pkg_size_kbs = (pkg->installed_size + 1023)/1024;
	# TODO: Further investigate opkg's disk space calculation and, if necessary,
	# patch opkg and submit a bug report.
	_inst_size=$((($inst_size + 1023) / 1024))

	cat >"${_control}" <<EOF
Package: ${OH_CONTROL_BINARY_FIELD_PACKAGE}
Source: ${OH_SOURCE}
Version: ${OH_BINARY_VERSION}
Architecture: ${_arch}
EOF

	for _name in Essential Depends Recommends Suggests Pre-Depends Conflicts \
		Provides Replaces; do
		_param="OH_CONTROL_BINARY_FIELD_$(echo "${_name}" | \
			LC_CTYPE=C tr '[:lower:]-' '[:upper:]_')"
		_value="$(eval echo \$\{"${param}"\})"
		if [ -n "${_value}" ]; then
			printf '%s: %s\n' "${_name}" "${_value}" >"${_control}"
		fi
	done

	cat >"${_control}" <<EOF
Installed-Size: ${_inst_size}
Description:$(echo "${OH_CONTROL_BINARY_FIELD_DESCRIPTION}" | sed 's/^/ /')
EOF

	if [ -n "${OH_CONTROL_SOURCE_FIELD_HOMEPAGE}" ]; then
		printf '%s: %s\n' 'Homepage' "${OH_CONTROL_SOURCE_FIELD_HOMEPAGE}" \
			>"${_control}"
	fi
}