#!/usr/bin/python3
# SPDX-License-Identifier: AGPL-3.0-or-later
"""
Configuration helper for Roundcube server.
"""

import argparse
import json
import pathlib
import re

from plinth import action_utils

_config_file = pathlib.Path('/etc/roundcube/freedombox-config.php')


def parse_arguments():
    """Return parsed command line arguments as dictionary."""
    parser = argparse.ArgumentParser()
    subparsers = parser.add_subparsers(dest='subcommand', help='Sub command')

    subparsers.add_parser('pre-install',
                          help='Perform Roundcube pre-install configuration')
    subparsers.add_parser('setup', help='Setup basic configuration')
    subparsers.add_parser('get-config', help='Print current configuration')
    subparser = subparsers.add_parser('set-config', help='Set configuration')
    subparser.add_argument('--local-only', choices=['True', 'False'],
                           help='Set current configuration')

    subparsers.required = True
    return parser.parse_args()


def subcommand_pre_install(_):
    """Preseed debconf values before packages are installed."""
    action_utils.debconf_set_selections([
        'roundcube-core roundcube/dbconfig-install boolean true',
        'roundcube-core roundcube/database-type string sqlite3'
    ])


def subcommand_setup(_):
    """Add FreedomBox configuration and include from main configuration."""
    if not _config_file.exists():
        _config_file.write_text('<?php\n')

    base_config = pathlib.Path('/etc/roundcube/config.inc.php')
    lines = base_config.read_text().splitlines()
    exists = any((str(_config_file) in line for line in lines))
    if not exists:
        lines.append(f'include_once("{_config_file}");\n')
        base_config.write_text('\n'.join(lines))


def subcommand_get_config(_):
    """Print the current configuration as JSON."""
    pattern = r'\s*\$config\[\s*\'([^\']*)\'\s*\]\s*=\s*\'([^\']*)\'\s*;'
    _config = {}
    try:
        for line in _config_file.read_text().splitlines():
            match = re.match(pattern, line)
            if match:
                _config[match.group(1)] = match.group(2)
    except FileNotFoundError:
        pass

    local_only = _config.get('default_host') == 'localhost'
    print(json.dumps({'local_only': local_only}))


def subcommand_set_config(arguments):
    """Set the configuration."""
    config = '<?php\n'
    if arguments.local_only == 'True':
        config = '''<?php
$config['default_host'] = 'localhost';
$config['mail_domain'] = '%n';

$config['smtp_server'] = 'localhost';
$config['smtp_port'] = 25;
$config['smtp_helo_host'] = 'localhost';
'''

    _config_file.write_text(config)


def main():
    """Parse arguments and perform all duties."""
    arguments = parse_arguments()

    subcommand = arguments.subcommand.replace('-', '_')
    subcommand_method = globals()['subcommand_' + subcommand]
    subcommand_method(arguments)


if __name__ == '__main__':
    main()