# Copyright 2023 (c) Anna Schumaker.
"""A cache to hold Gdk.Textures used by cover art."""
import pathlib
from gi.repository import Gdk


class _TextureCache(dict):
    """A custom dictionary for storing texture files."""

    def __missing__(self, path: pathlib.Path | None) -> Gdk.Texture:
        """Load a cache item from disk or add a new item entirely."""
        texture = Gdk.Texture.new_from_filename(str(path))
        self.__setitem__(path, texture)
        return texture

    def __getitem__(self, path: pathlib.Path | None) -> Gdk.Texture | None:
        """Get a Gdk.Texture cache item from the cache."""
        if path is not None and path.is_file():
            return super().__getitem__(path)

    def drop(self, path: pathlib.Path | None) -> None:
        """Drop a single cache item from the cache."""
        self.pop(path, None)


CACHE = _TextureCache()