# ABOUTME: Tests for wallpaper path resolution.
# ABOUTME: Verifies fallback hierarchy: config > Moonarch system default > package fallback.

from pathlib import Path
from unittest.mock import patch

from moonlock.config import Config, resolve_background_path, MOONARCH_WALLPAPER, PACKAGE_WALLPAPER


class TestResolveBackgroundPath:
    """Tests for the wallpaper fallback hierarchy."""

    def test_config_path_used_when_file_exists(self, tmp_path: Path):
        """Config background_path takes priority if the file exists."""
        wallpaper = tmp_path / "custom.jpg"
        wallpaper.write_bytes(b"\xff\xd8")
        config = Config(background_path=str(wallpaper))
        result = resolve_background_path(config)
        assert result == wallpaper

    def test_config_path_skipped_when_file_missing(self, tmp_path: Path):
        """Config path should be skipped if the file does not exist."""
        config = Config(background_path="/nonexistent/wallpaper.jpg")
        with patch("moonlock.config.MOONARCH_WALLPAPER", tmp_path / "nope.jpg"):
            result = resolve_background_path(config)
        assert result == PACKAGE_WALLPAPER

    def test_moonarch_default_used_when_no_config(self, tmp_path: Path):
        """Moonarch system wallpaper is used when config has no background_path."""
        moonarch_wp = tmp_path / "wallpaper.jpg"
        moonarch_wp.write_bytes(b"\xff\xd8")
        config = Config(background_path=None)
        with patch("moonlock.config.MOONARCH_WALLPAPER", moonarch_wp):
            result = resolve_background_path(config)
        assert result == moonarch_wp

    def test_moonarch_default_skipped_when_missing(self, tmp_path: Path):
        """Falls back to package wallpaper when Moonarch default is missing."""
        config = Config(background_path=None)
        with patch("moonlock.config.MOONARCH_WALLPAPER", tmp_path / "nope.jpg"):
            result = resolve_background_path(config)
        assert result == PACKAGE_WALLPAPER

    def test_package_fallback_always_exists(self):
        """The package fallback wallpaper must always be present."""
        assert PACKAGE_WALLPAPER.is_file()

    def test_full_fallback_chain(self, tmp_path: Path):
        """With no config and no Moonarch default, package fallback is returned."""
        config = Config()
        with patch("moonlock.config.MOONARCH_WALLPAPER", tmp_path / "nope.jpg"):
            result = resolve_background_path(config)
        assert result == PACKAGE_WALLPAPER