"""Base interface every screen implements."""

from abc import ABC, abstractmethod
from typing import Any

from PIL import Image


class Screen(ABC):
    id: str
    display_name: str
    poll_interval: int = 60  # seconds between check() calls

    @abstractmethod
    def check(self, settings: dict) -> Any:
        """Cheap call (ideally a single small request) that returns whatever
        state this screen needs to render. Returning None means "nothing to
        show" (only meaningful for preemptive screens like Navidrome)."""

    @abstractmethod
    def render(self, state: Any, settings: dict, resolution: tuple[int, int]) -> Image.Image:
        """Full draw. Only called when this screen is actually about to be
        shown, so it's fine for this to be more expensive than check()."""

    def default_settings(self) -> dict:
        """Settings this screen needs, with defaults, merged under config.json's
        settings[self.id] on first run."""
        return {}