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

import argparse
import os
import subprocess
import sys
import tempfile

from plinth.utils import generate_password

MAINTENANCE_SCRIPTS_DIR = "/usr/share/mediawiki/maintenance"
CONF_FILE = '/etc/mediawiki/FreedomBoxSettings.php'
LOCAL_SETTINGS_CONF = '/etc/mediawiki/LocalSettings.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('setup', help='Setup MediaWiki')
    subparsers.add_parser('update', help='Run MediaWiki update script')

    help_pub_reg = 'Enable/Disable/Status public user registration.'
    pub_reg = subparsers.add_parser('public-registrations', help=help_pub_reg)
    pub_reg.add_argument('command', choices=('enable', 'disable', 'status'),
                         help=help_pub_reg)

    help_private_mode = 'Enable/Disable/Status private mode.'
    private_mode = subparsers.add_parser('private-mode',
                                         help=help_private_mode)
    private_mode.add_argument('command',
                              choices=('enable', 'disable', 'status'),
                              help=help_private_mode)

    change_password = subparsers.add_parser('change-password',
                                            help='Change user password')
    change_password.add_argument('--username', default='admin',
                                 help='name of the MediaWiki user')
    change_password.add_argument('--password',
                                 help='new password for the MediaWiki user')

    default_skin = subparsers.add_parser('set-default-skin',
                                         help='Set the default skin')
    default_skin.add_argument('skin', help='name of the skin')

    subparsers.required = True
    return parser.parse_args()


def subcommand_setup(_):
    """Run the installer script to create database and configuration file."""
    data_dir = '/var/lib/mediawiki-db/'
    if not os.path.exists(data_dir):
        os.mkdir(data_dir)

    if not os.path.exists(os.path.join(data_dir, 'my_wiki.sqlite')) or \
       not os.path.exists(LOCAL_SETTINGS_CONF):
        install_script = os.path.join(MAINTENANCE_SCRIPTS_DIR, 'install.php')
        password = generate_password()
        with tempfile.NamedTemporaryFile() as password_file_handle:
            password_file_handle.write(password.encode())
            subprocess.check_call([
                'php', install_script, '--confpath=/etc/mediawiki',
                '--dbtype=sqlite', '--dbpath=' + data_dir,
                '--scriptpath=/mediawiki', '--passfile',
                password_file_handle.name, 'Wiki', 'admin'
            ])
    subprocess.run(['chmod', '-R', 'o-rwx', data_dir], check=True)
    subprocess.run(['chown', '-R', 'www-data:www-data', data_dir], check=True)
    include_custom_config()


def include_custom_config():
    """Include FreedomBox specific configuration in LocalSettings.php."""
    with open(LOCAL_SETTINGS_CONF, 'r') as conf_file:
        lines = conf_file.readlines()

    static_settings_index = None
    settings_index = None
    for line_number, line in enumerate(lines):
        if 'FreedomBoxSettings.php' in line:
            settings_index = line_number

        if 'FreedomBoxStaticSettings.php' in line:
            static_settings_index = line_number

    if settings_index is None:
        settings_index = len(lines)
        lines.append('include dirname(__FILE__)."/FreedomBoxSettings.php";\n')

    if static_settings_index is None:
        lines.insert(
            settings_index,
            'include dirname(__FILE__)."/FreedomBoxStaticSettings.php";\n')

    with open(LOCAL_SETTINGS_CONF, 'w') as conf_file:
        conf_file.writelines(lines)


def subcommand_change_password(arguments):
    """Change the password for a given user"""
    new_password = ''.join(sys.stdin)
    change_password_script = os.path.join(MAINTENANCE_SCRIPTS_DIR,
                                          'changePassword.php')

    subprocess.check_call([
        'php', change_password_script, '--user', arguments.username,
        '--password', new_password
    ])


def subcommand_update(_):
    """Run update.php maintenance script when version upgrades happen."""
    update_script = os.path.join(MAINTENANCE_SCRIPTS_DIR, 'update.php')
    subprocess.check_call(['php', update_script, '--quick'])


def subcommand_public_registrations(arguments):
    """Enable or Disable public registrations for MediaWiki."""

    with open(CONF_FILE, 'r') as conf_file:
        lines = conf_file.readlines()

    def is_pub_reg_line(line):
        return line.startswith("$wgGroupPermissions['*']['createaccount']")

    if arguments.command == 'status':
        conf_lines = list(filter(is_pub_reg_line, lines))
        if conf_lines:
            print('enabled' if 'true' in conf_lines[0] else 'disabled')
        else:
            print('disabled')
    else:
        with open(CONF_FILE, 'w') as conf_file:
            for line in lines:
                if is_pub_reg_line(line):
                    words = line.split()
                    if arguments.command == 'enable':
                        words[-1] = 'true;'
                    else:
                        words[-1] = 'false;'
                    conf_file.write(" ".join(words) + '\n')
                else:
                    conf_file.write(line)


def subcommand_private_mode(arguments):
    """Enable or Disable Private mode for wiki"""
    with open(CONF_FILE, 'r') as conf_file:
        lines = conf_file.readlines()

    def is_edit_line(line):
        return line.startswith("$wgGroupPermissions['*']['edit']")

    def is_read_line(line):
        return line.startswith("$wgGroupPermissions['*']['read']")

    edit_conf_lines = list(filter(is_edit_line, lines))
    read_conf_lines = list(filter(is_read_line, lines))
    if arguments.command == 'status':
        if edit_conf_lines and read_conf_lines:
            print('enabled' if ('false' in read_conf_lines[0]) and (
                'false' in edit_conf_lines[0]) else 'disabled')
        else:
            print('disabled')
    else:
        with open(CONF_FILE, 'w') as conf_file:
            conf_value = 'false;' if arguments.command == 'enable' else 'true;'
            for line in lines:
                if is_edit_line(line) or is_read_line(line):
                    words = line.split()
                    words[-1] = conf_value
                    conf_file.write(" ".join(words) + '\n')
                else:
                    conf_file.write(line)

            if not edit_conf_lines:
                conf_file.write("$wgGroupPermissions['*']['edit'] = " +
                                conf_value + '\n')
            if not read_conf_lines:
                conf_file.write("$wgGroupPermissions['*']['read'] = " +
                                conf_value + '\n')


def subcommand_set_default_skin(arguments):
    """Set a default skin"""
    skin = arguments.skin
    skin_setting = f'$wgDefaultSkin = "{skin}";\n'

    with open(CONF_FILE, 'r') as conf_file:
        lines = conf_file.readlines()

        inserted = False
        for i, line in enumerate(lines):
            if line.strip().startswith('$wgDefaultSkin'):
                lines[i] = skin_setting
                inserted = True
                break

        if not inserted:
            lines.append(skin_setting)

    with open(CONF_FILE, 'w') as conf_file:
        conf_file.writelines(lines)


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()
