"""
Auth Service registry — generic, pluggable authentication for any service.

Add a new service (Plex, Seerr, etc.) by:
1. Subclassing AuthService
2. Dropping the module in this package
3. Calling register_auth_service() at import time
"""

from __future__ import annotations

from abc import ABC, abstractmethod
from dataclasses import dataclass, field
from typing import Optional


# ---------------------------------------------------------------------------
# AuthResult — returned by AuthService.authenticate()
# ---------------------------------------------------------------------------

@dataclass
class AuthResult:
    """Outcome of a credential validation attempt."""
    success: bool
    external_user_id: Optional[str] = None
    external_name: Optional[str] = None
    credentials: Optional[dict] = None
    error_message: Optional[str] = None


# ---------------------------------------------------------------------------
# AuthService — abstract base class
# ---------------------------------------------------------------------------

class AuthService(ABC):
    """A service that users can authenticate against (Jellyfin, Seerr, Plex, etc.)

    Subclasses must implement:
      - name          : unique identifier used in URLs and DB keys
      - display_name  : human-readable label shown in Discord
      - render_login_form(token, discord_id) → HTML string
      - authenticate(form_data) → AuthResult
    """

    @property
    @abstractmethod
    def name(self) -> str:
        """Unique service name: "jellyfin", "seerr", etc."""
        ...

    @property
    @abstractmethod
    def display_name(self) -> str:
        """Human-readable: "Jellyfin", "Seerr", "Plex" """
        ...

    @abstractmethod
    def render_login_form(self, token: str, discord_id: int) -> str:
        """Return HTML string with a login form for this service.

        The form MUST include these hidden fields:
          <input type="hidden" name="token" value="{token}">
          <input type="hidden" name="discord_id" value="{discord_id}">
          <input type="hidden" name="service" value="{self.name}">
        """
        ...

    @abstractmethod
    async def authenticate(self, form_data: dict) -> AuthResult:
        """Validate credentials against the service. Return AuthResult."""
        ...


# ---------------------------------------------------------------------------
# Global registry
# ---------------------------------------------------------------------------

_registry: dict[str, AuthService] = {}


def register_auth_service(svc: AuthService) -> None:
    """Register an AuthService so it can be looked up by name."""
    _registry[svc.name] = svc


def get_auth_service(name: str) -> AuthService | None:
    """Look up a registered AuthService by name."""
    return _registry.get(name)


def list_auth_services() -> list[str]:
    """Return names of all registered auth services."""
    return list(_registry.keys())