import configparser
import os
from typing import Final

import validators

from mdrsclient.exceptions import IllegalArgumentException
from mdrsclient.settings import CONFIG_FILE_PATH


class ConfigFile:
    OPTION_URL: Final[str] = "url"

    serial: int
    config_file: str
    config_dir: str
    remote: str
    config: configparser.ConfigParser

    def __init__(self, remote: str) -> None:
        self.serial = -1
        self.config_file = CONFIG_FILE_PATH
        self.config_dir = os.path.dirname(CONFIG_FILE_PATH)
        self.remote = remote
        self.config = configparser.ConfigParser()

    def list(self) -> list[tuple[str, str]]:
        ret: list[tuple[str, str]] = []
        self.__load()
        for remote in self.config.sections():
            url = self.config.get(remote, self.OPTION_URL)
            ret.append((remote, url))
        return ret

    @property
    def url(self) -> str | None:
        if not self.__exists(self.remote):
            return None
        return self.config.get(self.remote, self.OPTION_URL)

    @url.setter
    def url(self, url: str) -> None:
        if not validators.url(url):  # type: ignore
            raise IllegalArgumentException("malformed URI sequence")
        self.__load()
        if self.config.has_section(self.remote):
            self.config.remove_section(self.remote)
        self.config.add_section(self.remote)
        self.config.set(self.remote, self.OPTION_URL, url)
        self.__save()

    @url.deleter
    def url(self) -> None:
        if self.__exists(self.remote):
            self.config.remove_section(self.remote)
            self.__save()

    def __exists(self, section: str) -> bool:
        self.__load()
        return self.config.has_option(section, self.OPTION_URL)

    def __load(self) -> None:
        if os.path.isfile(self.config_file):
            stat = os.stat(self.config_file)
            serial = hash(stat)
            if self.serial != serial:
                self.config.read(self.config_file, encoding="utf8")
                self.serial = serial

    def __save(self) -> None:
        self.__ensure_cache_dir()
        with open(self.config_file, "w") as f:
            self.config.write(f)
        os.chmod(self.config_file, 0o600)

    def __ensure_cache_dir(self) -> None:
        if not os.path.exists(self.config_dir):
            os.makedirs(self.config_dir)
        # ensure directory is secure.
        os.chmod(self.config_dir, 0o700)