import contextlib
import io
import tempfile
import unittest
from pathlib import Path
from unittest.mock import patch

import pandas as pd
from PIL import Image

from copienator.commands import add_final_score


class AddFinalScoreTests(unittest.TestCase):
    def test_creates_complete_student_directory(self):
        with tempfile.TemporaryDirectory() as temporary:
            root = Path(temporary)
            source = root / "A Rendre" / "Student (01)"
            answers = source / "answers"
            answers.mkdir(parents=True)
            Image.new("RGB", (300, 200), "white").save(source / "Student.jpg")
            (source / "Student.pdf").write_bytes(b"pdf")
            (source / "score.json").write_bytes(b'{"Ex 1": "4"}')
            (source / "info.json").write_bytes(b'{"Ex 1": {}}')
            (answers / "Ex 1.jpg").write_bytes(b"answer")

            output = root / "output"
            output.mkdir()
            (output / "Student.jpg").write_bytes(b"legacy jpeg")
            (output / "Student.pdf").write_bytes(b"legacy pdf")
            stale_answers = output / "Student" / "answers"
            stale_answers.mkdir(parents=True)
            (stale_answers / "001 - Ex 1.jpg").write_bytes(b"stale")
            scores = pd.DataFrame({0: ["Student"], 1: [12.39]})
            histogram = root / "histogramme.pdf"
            histogram.write_bytes(b"histogram")
            with patch.object(add_final_score.pd, "read_excel", return_value=scores), \
                    patch.object(add_final_score, "HISTOGRAM_PATH", histogram), \
                    contextlib.redirect_stdout(io.StringIO()):
                add_final_score.process_images(root, output)

            student = output / "Student"
            self.assertEqual(
                {path.name for path in student.iterdir()},
                {"Student.jpg", "Student.pdf", "score.json", "info.json", "answers"},
            )
            self.assertEqual((student / "Student.pdf").read_bytes(), b"pdf")
            self.assertEqual((student / "score.json").read_bytes(), b'{"Ex 1": "4"}')
            self.assertEqual((student / "info.json").read_bytes(), b'{"Ex 1": {}}')
            self.assertEqual(
                (student / "answers" / "Ex 1.jpg").read_bytes(), b"answer"
            )
            self.assertFalse((output / "Student.jpg").exists())
            self.assertFalse((output / "Student.pdf").exists())
            self.assertFalse((student / "answers" / "001 - Ex 1.jpg").exists())
            self.assertEqual((output / "histogramme.pdf").read_bytes(), b"histogram")

    def test_omits_answers_directory_when_it_was_not_generated(self):
        with tempfile.TemporaryDirectory() as temporary:
            root = Path(temporary)
            source = root / "A Rendre" / "Student (01)"
            source.mkdir(parents=True)
            Image.new("RGB", (300, 200), "white").save(source / "Student.jpg")
            (source / "Student.pdf").write_bytes(b"pdf")
            (source / "score.json").write_text("{}")
            (source / "info.json").write_text("{}")

            output = root / "output"
            scores = pd.DataFrame({0: ["Student"], 1: [10]})
            with patch.object(add_final_score.pd, "read_excel", return_value=scores), \
                    contextlib.redirect_stdout(io.StringIO()):
                add_final_score.process_images(root, output)

            self.assertFalse((output / "Student" / "answers").exists())

    def test_missing_histogram_warns_without_discarding_student_outputs(self):
        with tempfile.TemporaryDirectory() as temporary:
            root = Path(temporary)
            source = root / "A Rendre" / "Student (01)"
            source.mkdir(parents=True)
            Image.new("RGB", (300, 200), "white").save(source / "Student.jpg")
            scores = pd.DataFrame({0: ["Student"], 1: [10]})
            output = root / "output"
            messages = io.StringIO()

            with patch.object(
                add_final_score.pd, "read_excel", return_value=scores
            ), patch.object(
                add_final_score, "HISTOGRAM_PATH", root / "missing.pdf"
            ), contextlib.redirect_stdout(messages):
                add_final_score.process_images(root, output)

            self.assertTrue((output / "Student" / "Student.jpg").is_file())
            self.assertFalse((output / "histogramme.pdf").exists())
            self.assertIn("Missing histogram", messages.getvalue())


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