"""Hermetic fixtures for the EPUB -> PDF converter suite.

Isolation contract
------------------
- ``DATA_DIR`` is redirected to a fresh temp dir BEFORE ``app`` is imported
  (app.py reads the env var at import time, app.py:36).
- The Flask test client is used: no live server, no port conflicts, while
  conversion worker threads still run in-process.
- The module-global ``JOBS`` registry is cleared before and after every test.
"""
import io
import os
import sys
import tempfile
from pathlib import Path

import pytest

ROOT = Path(__file__).resolve().parents[1]
sys.path.insert(0, str(ROOT))

# Must happen before importing app — app.py bakes DATA_DIR in at import time.
os.environ["DATA_DIR"] = tempfile.mkdtemp(prefix="epub2pdf-tests-")

import app  # noqa: E402

FIXTURE_EBOOK = ROOT / "test_book.epub"


@pytest.fixture(scope="module")
def client():
    """Flask test client for the module-level app instance."""
    app.app.config["TESTING"] = True
    with app.app.test_client() as c:
        yield c


@pytest.fixture(autouse=True)
def _isolate_jobs():
    """Every test starts with (and leaves) an empty job registry."""
    app.JOBS.clear()
    yield
    app.JOBS.clear()


@pytest.fixture(scope="module")
def fixture_epub_bytes():
    """Raw bytes of the checked-in test book (em dashes + CJK)."""
    return FIXTURE_EBOOK.read_bytes()


@pytest.fixture(scope="module")
def submit_epub(client, fixture_epub_bytes):
    """Factory: POST an upload to /api/convert; returns the response."""
    def _submit(filename="book.epub", content=None):
        if content is None:
            content = fixture_epub_bytes
        files = {"file": (io.BytesIO(content), filename)}
        return client.post(
            "/api/convert", data=files, content_type="multipart/form-data"
        )
    return _submit