from __future__ import annotations

import importlib.util
from io import BytesIO
from pathlib import Path
import tempfile
import unittest

from PIL import Image


PLUGIN_ROOT = Path(__file__).resolve().parents[1]
MODULE_PATH = PLUGIN_ROOT / "utils" / "o1key_image_thumbnail.py"
SPEC = importlib.util.spec_from_file_location("o1key_image_thumbnail_under_test", MODULE_PATH)
MODULE = importlib.util.module_from_spec(SPEC)
assert SPEC and SPEC.loader
SPEC.loader.exec_module(MODULE)


class _FolderPaths:
    def __init__(self, roots):
        self.roots = roots

    def get_directory_by_type(self, folder_type):
        return self.roots.get(folder_type)


class O1keyImageThumbnailTests(unittest.TestCase):
    def test_thumbnail_is_bounded_and_source_is_untouched(self):
        with tempfile.TemporaryDirectory() as directory:
            source = Path(directory, "large.png")
            Image.new("RGB", (1800, 900), (30, 80, 120)).save(source)
            original = source.read_bytes()

            encoded = MODULE.render_reference_thumbnail(str(source))

            self.assertEqual(source.read_bytes(), original)
            with Image.open(BytesIO(encoded)) as thumbnail:
                self.assertEqual(thumbnail.format, "WEBP")
                self.assertEqual(thumbnail.size, (256, 128))

    def test_resolver_accepts_scoped_descriptor_and_rejects_traversal(self):
        with tempfile.TemporaryDirectory() as directory:
            input_root = Path(directory, "input")
            nested = input_root / "legacy"
            nested.mkdir(parents=True)
            source = nested / "reference.png"
            source.write_bytes(b"image")
            folder_paths = _FolderPaths({"input": str(input_root)})

            resolved = MODULE.resolve_thumbnail_source(
                folder_paths,
                "reference.png",
                "legacy",
                "input",
            )
            self.assertEqual(Path(resolved), source.resolve())
            with self.assertRaisesRegex(ValueError, "子目录无效"):
                MODULE.resolve_thumbnail_source(
                    folder_paths,
                    "reference.png",
                    "../outside",
                    "input",
                )
            with self.assertRaisesRegex(ValueError, "目录类型无效"):
                MODULE.resolve_thumbnail_source(
                    folder_paths,
                    "reference.png",
                    "legacy",
                    "private",
                )


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