# Copyright 2019 New Vector Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from configparser import ConfigParser

from sydent.config.crypto import CryptoConfig
from sydent.config.database import DatabaseConfig
from sydent.config.email import EmailConfig
from sydent.config.general import GeneralConfig
from sydent.config.http import HTTPConfig
from sydent.config.sms import SMSConfig


class ConfigError(Exception):
    pass


class SydentConfig:
    """This is the class in charge of handling Sydent's configuration.
    Handling of each individual section is delegated to other classes
    stored in a `config_sections` list.
    """

    def __init__(self):
        self.general = GeneralConfig()
        self.database = DatabaseConfig()
        self.crypto = CryptoConfig()
        self.sms = SMSConfig()
        self.email = EmailConfig()
        self.http = HTTPConfig()

        self.config_sections = [
            self.general,
            self.database,
            self.crypto,
            self.sms,
            self.email,
            self.http,
        ]

    def _parse_config(self, cfg: ConfigParser) -> None:
        """
        Run the parse_config method on each of the objects in
        self.config_sections

        :param cfg: the configuration to be parsed
        """
        for section in self.config_sections:
            section.parse_config(cfg)

    def parse_from_config_parser(self, cfg: ConfigParser) -> bool:
        """
        Parse the configuration from a ConfigParser object

        :param cfg: the configuration to be parsed
        ...
        :return: Whether or not cfg has been changed and needs saving
        """
        self._parse_config(cfg)

        # TODO: Don't alter config file when starting Sydent unless
        #       user has asked for this specifially (e.g. on first
        #       run only, or when specify --generate-config)
        return self.crypto.save_key