import unittest
from pathlib import Path

from scripts.optimize_assets import (
    build_webp_path,
    classify_large_image,
    should_keep_conversion,
    should_prune_original,
)


class OptimizeAssetsRulesTest(unittest.TestCase):
    def test_rejects_webp_when_not_smaller_than_source(self) -> None:
        self.assertFalse(should_keep_conversion(120_000, 123_000))

    def test_accepts_materially_smaller_webp_for_large_file(self) -> None:
        self.assertTrue(should_keep_conversion(500_000, 430_000))

    def test_rejects_small_gain_below_threshold(self) -> None:
        self.assertFalse(should_keep_conversion(200_000, 191_000))

    def test_flags_large_by_filesize(self) -> None:
        self.assertTrue(classify_large_image(301_000, 1200, 900))

    def test_flags_large_by_dimensions(self) -> None:
        self.assertTrue(classify_large_image(120_000, 3000, 1800))

    def test_uses_extension_qualified_webp_name_when_stem_collides(self) -> None:
        target = build_webp_path(Path("assets/images/sj.jpg"), {"assets/images/sj"})
        self.assertEqual(target.as_posix(), "assets/images/sj.jpg.webp")

    def test_prunes_original_when_webp_exists_and_original_is_unreferenced(self) -> None:
        self.assertTrue(
            should_prune_original(
                Path("assets/images/banner.jpg"),
                {"index.html", "assets/images/banner.webp"},
                {"assets/images/banner.webp"},
            )
        )


if __name__ == "__main__":
    unittest.main()