# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.

from argparse import (
    Action,
    ArgumentParser,
)
import os
import subprocess
import sys
import tempfile

import buildconfig


class CPPFlag(Action):
    all_flags = []

    def __call__(self, parser, namespace, values, option_string=None):
        if 'windres' in buildconfig.substs['RC'].lower():
            if option_string == '-U':
                return
            if option_string == '-I':
                option_string = '--include-dir'

        self.all_flags.extend((option_string, values))


def generate_res():
    parser = ArgumentParser()
    parser.add_argument('-D', action=CPPFlag, metavar='VAR[=VAL]', help='Define a variable')
    parser.add_argument('-U', action=CPPFlag, metavar='VAR', help='Undefine a variable')
    parser.add_argument('-I', action=CPPFlag, metavar='DIR', help='Search path for includes')
    parser.add_argument('-o', dest='output', metavar='OUTPUT', help='Output file')
    parser.add_argument('input', help='Input file')
    args = parser.parse_args()

    is_windres = 'windres' in buildconfig.substs['RC'].lower()

    verbose = os.environ.get('BUILD_VERBOSE_LOG')

    # llvm-rc doesn't preprocess on its own, so preprocess manually
    # Theoretically, not windres could be rc.exe, but configure won't use it
    # unless you really ask for it, and it will still work with preprocessed
    # output.
    try:
        if not is_windres:
            fd, path = tempfile.mkstemp(suffix='.rc')
            command = buildconfig.substs['CXXCPP'] + CPPFlag.all_flags
            command.extend(('-DRC_INVOKED', args.input))
            if verbose:
                print('Executing:', ' '.join(command))
            with os.fdopen(fd, 'wb') as fh:
                retcode = subprocess.run(command, stdout=fh).returncode
                if retcode:
                    # Rely on the subprocess printing out any relevant error
                    return retcode
        else:
            path = args.input

        command = [buildconfig.substs['RC']]
        if is_windres:
            command.extend(('-O', 'coff'))

        # Even though llvm-rc doesn't preprocess, we still need to pass at least
        # the -I flags.
        command.extend(CPPFlag.all_flags)

        if args.output:
            if is_windres:
                command.extend(('-o', args.output))
            else:
                # Use win1252 code page for the input.
                command.extend(('-c', '1252', '-Fo' + args.output))

        command.append(path)

        if verbose:
            print('Executing:', ' '.join(command))
        retcode = subprocess.run(command).returncode
        if retcode:
            # Rely on the subprocess printing out any relevant error
            return retcode
    finally:
        if path != args.input:
            os.remove(path)

    return 0


if __name__ == '__main__':
    sys.exit(generate_res())