"""
auth.py
SkyOS Google Authentication

Stellt authentifizierte Google Services für alle Module bereit.

Autor: Sky Meilin
Projekt: SkyOS Full Core
"""

from __future__ import annotations

import logging

from googleapiclient.discovery import build

from Module.google.oauth import oauth

logger = logging.getLogger("SkyOS.GoogleAuth")


class GoogleAuth:
    """Zentrale Google-Authentifizierung."""

    _credentials = None
    _services = {}

    @classmethod
    def credentials(cls):
        """Liefert gültige OAuth-Credentials."""

        if cls._credentials is None:
            cls._credentials = oauth.authenticate()

        return cls._credentials

    @classmethod
    def service(
        cls,
        api_name: str,
        api_version: str,
    ):
        """
        Erzeugt oder liefert einen zwischengespeicherten Google-Service.

        Beispiel:
            GoogleAuth.service("drive", "v3")
        """

        key = f"{api_name}:{api_version}"

        if key not in cls._services:

            logger.info(
                "Initialisiere Google Service %s (%s)",
                api_name,
                api_version,
            )

            cls._services[key] = build(
                api_name,
                api_version,
                credentials=cls.credentials(),
                cache_discovery=False,
            )

        return cls._services[key]

    @classmethod
    def reset(cls):
        """Setzt alle gecachten Services zurück."""

        cls._services.clear()
        cls._credentials = None


# -------------------------------------------------
# Komfortfunktionen
# -------------------------------------------------

def get_credentials():
    """Liefert gültige OAuth-Credentials."""
    return GoogleAuth.credentials()


def get_service(
    api_name: str,
    api_version: str,
):
    """
    Liefert einen Google API Service.

    Beispiele:
        get_service("drive", "v3")
        get_service("calendar", "v3")
        get_service("gmail", "v1")
    """

    return GoogleAuth.service(
        api_name,
        api_version,
    )


# -------------------------------------------------
# Spezielle Kurzfunktionen
# -------------------------------------------------

def drive():
    return get_service("drive", "v3")


def docs():
    return get_service("docs", "v1")


def sheets():
    return get_service("sheets", "v4")


def gmail():
    return get_service("gmail", "v1")


def calendar():
    return get_service("calendar", "v3")