import hashlib
import tempfile
import unittest
from pathlib import Path

from PIL import Image

from cover import generate_cover


class CoverTests(unittest.TestCase):
    def test_generates_deterministic_1200x630_jpeg_under_5mb(self):
        output_dir = Path(tempfile.mkdtemp())
        first = generate_cover("arabic-ai-guide", "أدوات", output_dir)
        first_hash = hashlib.sha256(first["path"].read_bytes()).hexdigest()
        second = generate_cover("arabic-ai-guide", "أدوات", output_dir)
        second_hash = hashlib.sha256(second["path"].read_bytes()).hexdigest()

        self.assertEqual(first_hash, second_hash)
        self.assertEqual(first["coverImage"]["filename"], "arabic-ai-guide.jpg")
        self.assertLessEqual(first["path"].stat().st_size, 5 * 1024 * 1024)
        with Image.open(first["path"]) as image:
            self.assertEqual(image.size, (1200, 630))
            self.assertEqual(image.format, "JPEG")
            self.assertEqual(image.mode, "RGB")

    def test_rejects_invalid_slug_or_category(self):
        output_dir = Path(tempfile.mkdtemp())
        with self.assertRaises(ValueError):
            generate_cover("عنوان عربي", "أدوات", output_dir)
        with self.assertRaises(ValueError):
            generate_cover("valid-slug", "عام", output_dir)


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