"""Provider abstraction (section 13).

A `MetadataProvider` fetches **raw**, unnormalized data from one external
source. It never writes to the database and never returns Aurora entities —
that's the normalizer/matcher/ingestion pipeline's job (see
`app/services/metadata/` and `app/services/ingestion/`). This keeps adapters
replaceable: swapping TMDb for another provider means writing a new class
here, not touching ingestion logic.
"""

from __future__ import annotations

from abc import ABC, abstractmethod
from typing import Any


class ProviderError(Exception):
    """Raised for any provider-side failure (auth, not-found, rate limit,
    network). Ingestion jobs catch this and record it, they don't crash."""


class ProviderNotConfiguredError(ProviderError):
    """Raised when a required credential (e.g. TMDB_API_KEY) is missing."""


class ProviderNotFoundError(ProviderError):
    """Raised when the provider has no record for the given external ID."""


class ProviderRateLimitedError(ProviderError):
    """Raised when the provider responds 429. Carries how long the provider
    itself asked callers to wait (`Retry-After`, seconds) so a caller can
    back off by the right amount rather than guessing — see
    `app/providers/tmdb.py:TMDbProvider._get` for where this is retried."""

    def __init__(self, message: str, *, retry_after: float) -> None:
        super().__init__(message)
        self.retry_after = retry_after


class MetadataProvider(ABC):
    slug: str
    name: str

    @abstractmethod
    async def get_movie(self, external_id: str) -> dict[str, Any]:
        """Fetch raw movie data, including credits/images/videos/keywords/
        alternate titles/external IDs/release dates where the provider
        supports fetching them in one call."""

    @abstractmethod
    async def get_series(self, external_id: str) -> dict[str, Any]:
        """Fetch raw series data (without season/episode bodies)."""

    @abstractmethod
    async def get_season(self, series_external_id: str, season_number: int) -> dict[str, Any]:
        """Fetch raw season data, including its episodes."""

    @abstractmethod
    async def get_person(self, external_id: str) -> dict[str, Any]:
        """Fetch raw person data, including external IDs and images."""

    @abstractmethod
    async def get_collection(self, external_id: str) -> dict[str, Any]:
        """Fetch raw collection/franchise data: name, overview, poster/
        backdrop, and its member movies (TMDb's "parts")."""

    @abstractmethod
    async def search_movie(self, query: str) -> list[dict[str, Any]]:
        """Search this provider's catalog for movies matching `query`. Used
        to seed ingestion, not exposed directly to API clients."""

    async def get_trending(self, media_type: str, time_window: str) -> list[dict[str, Any]]:
        """Fetch a ranked list of raw items (movies or series, per
        `media_type`) currently trending over `time_window` ("day" |
        "week"). Not every provider has a trending concept, so this is
        concrete rather than abstract (like `aclose` below) — a provider
        that doesn't support it simply doesn't override this, and callers
        get an empty list rather than every other provider implementation
        having to stub out a method that means nothing for them."""

        return []

    async def aclose(self) -> None:
        """Release any held resources (HTTP clients, ...). Optional."""