#!@@SHELL@@
#
# opkhelper
# lib/controlfields
# Functions for parsing control fields.
#
# 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/>.

# Gets a control field value.
# Parameters:
#   package name (if omitted, source package control file is read)
#   field name
# Output:
#   field value
# Return value:
#   0 on success
#   1 on missing field
#   255 on invalid invocation
#oh_get_folded_multiline_field()
oh_get_field()
{
	case ${#} in
		1)
			_control=../control
			_field=${1}
			;;
		2)
			_control=../${1}.pkg/control
			_field=${2}
			;;
		*)
			return 255
			;;
	esac

	# Force the 'read' utility to read until a line break character.
	_OLDIFS="${IFS}"
	IFS='
'

	# Parse the control file.
	_value=''
	while read -r _line; do
		if [ -z "${_value}" ]; then
			_value=$(echo "${_line}" | sed -n \
			"s/^${_field}:[[:space:]]*\(.*\)[[:space:]]*$/\\1/p")
		else
			if echo "${_line}" | grep '^ ' > /dev/null; then
				_value="${_value}
${_line}"
			else
				break
			fi
		fi
	done < ${_control}

	# Reset the IFS.
	IFS="${_OLDIFS}"

	[ -z "${_value}" ] && return 1
	echo "${_value}"
	return 0
}

# Validates a package name.
# Parameters:
#   package name
# Return value:
#   0 on valid name
#   1 on invalid name
oh_validate_pkg_name()
{
	echo "${1}" | grep -E '^[a-z0-9][a-z0-9.+-]+$' > /dev/null
	return ${?}
}