#  This program source code file is part of KICAD, a free EDA CAD application.
#
#  Copyright (C) 2020 Kicad Developers, see AUTHORS.txt for contributors.
#
#  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 2
#  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, you may find one here:
#  http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
#  or you may search the http://www.gnu.org website for the version 2 license,
#  or you may write to the Free Software Foundation, Inc.,
#  51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
#

# This file takes the following variables as arguments:
#   * LEMON_EXE - The absolute path to the lemon executable
#   * LEMON_TEMPLATE - The absolute path to the lemon template file
#   * GRAMMAR_FILE - The file of the grammar to use
#   * GRAMMAR_DIR - An absolute path to where the grammar should be generated


# Get the name without extension
get_filename_component( GRAMMAR_BASE ${GRAMMAR_FILE} NAME_WE )

# Only regenerate the lemon code if the grammar is newer than the current code
if( ${GRAMMAR_FILE} IS_NEWER_THAN ${GRAMMAR_DIR}/${GRAMMAR_BASE}.c )

    execute_process(
        COMMAND ${LEMON_EXE} -T${LEMON_TEMPLATE} -d${GRAMMAR_DIR} -q ${GRAMMAR_FILE}
        WORKING_DIRECTORY ${GRAMMAR_DIR}
        OUTPUT_VARIABLE _lemon_output
        ERROR_VARIABLE  _lemon_error
        RESULT_VARIABLE _lemon_result
        OUTPUT_STRIP_TRAILING_WHITESPACE
        )

    if( NOT ${_lemon_result} EQUAL 0)
        message( FATAL_ERROR "Lemon generator for ${GRAMMAR_FILE} has failed\n"
                             "Error: ${_lemon_error}" )
    endif()

endif()