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

from copienator import utils


class CompileToPdfTests(unittest.TestCase):
    def test_warns_when_latex_fails_even_if_partial_pdf_exists(self):
        with tempfile.TemporaryDirectory() as temporary:
            output = Path(temporary) / "result.pdf"

            def failed_run(*_args, **kwargs):
                (Path(kwargs["cwd"]) / "text.pdf").write_bytes(b"partial")
                return subprocess.CompletedProcess(
                    args=[], returncode=1,
                    stdout="! LaTeX Error: Something's wrong--perhaps a missing \\item.\n",
                )

            console = io.StringIO()
            with patch.object(utils.subprocess, "run", side_effect=failed_run), \
                    contextlib.redirect_stdout(console):
                utils.compile_to_pdf("broken", output)

            self.assertEqual(output.read_bytes(), b"partial")
            self.assertIn("Warning: LaTeX compilation failed", console.getvalue())
            self.assertIn("missing \\item", console.getvalue())

    def test_warns_when_no_pdf_is_produced(self):
        with tempfile.TemporaryDirectory() as temporary:
            output = Path(temporary) / "result.pdf"
            result = subprocess.CompletedProcess(args=[], returncode=0, stdout="")

            console = io.StringIO()
            with patch.object(utils.subprocess, "run", return_value=result), \
                    contextlib.redirect_stdout(console):
                utils.compile_to_pdf("valid", output)

            self.assertFalse(output.exists())
            self.assertIn("produced no PDF", console.getvalue())


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