#!@@SHELL@@
#
# opkhelper
# lib/changelog
# Functions for parsing changelogs.
#
# 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/>.

. @@LIBDIR@@/opkhelper/messages

oh_changelog_parse_error()
{
	_file="${1}"
	_line_nr="${2}"
	_error="${3}"
	_expect_id="${4}"

	case "${_expect_id}" in
		FIRST_HEADING)      _expect_str='first heading';;
		NEXT_OR_EOF)        _expect_str='next heading or eof';;
		START_CHANGES)      _expect_str='start of change data';;
		CHANGES_OR_TRAILER) _expect_str='more change data or trailer';;
		*)                  _expect_str='unknown';;
	esac

	_file_info=$(printf '%20s(l%d):' "${_file}" "${_line_nr}")
	oh_warn "${_file_info} ${_error}" "${_expect_str}"
}

oh_changelog_parse()
{
	# Parsing logic based on that of dpkg.

	_file="${1}"
	_cb="${2}"

	_expect=FIRST_HEADING
	_line_nr=0
	_entries=0

	while IFS= read _line; do
		_line_nr=$(($_line_nr + 1))
		if [ -z "${_line}" ]; then
			if [ "${_expect}" = START_CHANGES ]; then
				OH_CHANGELOG_CHANGES="${OH_CHANGELOG_CHANGES}
${_line}"
			elif [ "${_expect}" = NEXT_OR_EOF ]; then
				:
			elif [ "${_expect}" != CHANGES_OR_TRAILER ]; then
				oh_changelog_parse_error "${_file}" "${_line_nr}" \
					'found blank line where expected %s' "${_expect}"
			else
				_blank_lines="${_blank_lines}
${_line}"
			fi
		elif [ "${_line# }" = "${_line}" ]; then
			if [ "${_expect}" != FIRST_HEADING -a \
					"${_expect}" != NEXT_OR_EOF ]; then
				oh_changelog_parse_error "${_file}" "${_line_nr}" \
					'found start of entry where expected %s' "${_expect}"
			fi
			_source="${_line%% (*}"
			_line_="${_line#* (}"
			_distribution="${_line_##*) }"
			_line_="${_line_%) *}"
			_version="${_line_}"
			if [ -z "${_source}" -o -z "${_distribution}" -o \
					-z "${_version}" -o \
					"${_version% *}" != "${_version}" ]; then
				oh_changelog_parse_error "${_file}" "${_line_nr}" \
					'badly formatted heading line'
				OH_CHANGELOG_SOURCE=
				OH_CHANGELOG_VERSION=
				OH_CHANGELOG_DISTRIBUTION=
				OH_CHANGELOG_CHANGES=
			else
				OH_CHANGELOG_SOURCE="${_source}"
				OH_CHANGELOG_VERSION="${_version}"
				OH_CHANGELOG_DISTRIBUTION="${_distribution}"
				OH_CHANGELOG_CHANGES="${_line}"
			fi
			_expect=START_CHANGES
			_blank_lines=
		elif [ "${_line# -- }" != "${_line}" ]; then
			if [ "${_expect}" != CHANGES_OR_TRAILER ]; then
				oh_changelog_parse_error "${_file}" "${_line_nr}" \
					'found trailer where expected %s' "${_expect}"
			fi
			_line="${_line# -- }"
			_maintainer="${_line%%  *}"
			_date="${_line#*  }"
			if [ -z "${_maintainer}" -o -z "${_date}" -o \
					"${_maintainer}" = "${_date}" ]; then
				oh_changelog_parse_error "${_file}" "${_line_nr}" \
					'badly formatted trailer line'
				OH_CHANGELOG_MAINTAINER=
				OH_CHANGELOG_DATE=
			elif [ -n "${OH_CHANGELOG_SOURCE}" ]; then
				OH_CHANGELOG_MAINTAINER="${_maintainer}"
				OH_CHANGELOG_DATE="${_date}"
				"${_cb}"
				_entries=$(($_entries + 1))
			fi
			_expect=NEXT_OR_EOF
			_blank_lines=
		elif [ "${_line# --}" != "${_line}" ]; then
			oh_changelog_parse_error "${_file}" "${_line_nr}" \
				'badly formatted trailer line'
		elif [ "${_line##  }" != "${_line}" ]; then
			if [ "${_expect}" != START_CHANGES -a \
					"${_expect}" != CHANGES_OR_TRAILER ]; then
				oh_changelog_parse_error "${_file}" "${_line_nr}" \
					'found change data where expected %s' "${_expect}"
			fi
			OH_CHANGELOG_CHANGES="${OH_CHANGELOG_CHANGES}
${_blank_lines}${_line}"
			_expect=CHANGES_OR_TRAILER
			_blank_lines=
		else
			oh_changelog_parse_error "${_file}" "${_line_nr}" \
				'unrecognized line'
			_blank_lines=
		fi
	done <"${_file}"

	if [ "${_expect}" != NEXT_OR_EOF ]; then
		oh_changelog_parse_error "${_file}" "${_line_nr}" \
			'found eof where expected %s' "${_expect}"
	fi

	return ${_entries}
}