"""Tests für Issue #2: --once Modus muss Exit-Code != 0 bei Fehlern liefern."""
from __future__ import annotations

from pathlib import Path
from unittest.mock import patch

from pdf_ocr_hotfolder.processor import ProcessResult
from pdf_ocr_hotfolder.service import HotfolderService


def _fake_success(src: Path, working_dir, outgoing_dir, error_dir, ocr_cfg, vera_cfg):
    out = outgoing_dir / f"OCR_{src.name}"
    out.parent.mkdir(parents=True, exist_ok=True)
    out.write_bytes(b"%PDF-1.4 ocr\n")
    src.unlink(missing_ok=True)
    return ProcessResult(src, out, True)


def _fake_failure(src: Path, working_dir, outgoing_dir, error_dir, ocr_cfg, vera_cfg):
    error_dir.mkdir(parents=True, exist_ok=True)
    dest = error_dir / src.name
    src.rename(dest)
    return ProcessResult(src, outgoing_dir / f"OCR_{src.name}", False,
                         error="fake ocr failure")


def _run(tmp_config, fake_process):
    """Helper: führt run_once() mit gemocktem process_pdf und preflight aus."""
    with patch("pdf_ocr_hotfolder.service.check_preflight", return_value=None), \
         patch("pdf_ocr_hotfolder.service.process_pdf", side_effect=fake_process), \
         patch("pdf_ocr_hotfolder.service._wait_until_stable", return_value=True):
        service = HotfolderService(tmp_config)
        try:
            return service.run_once()
        finally:
            service._executor.shutdown(wait=False)


def test_once_exit_0_when_no_files(tmp_config) -> None:
    """Szenario: Keine PDFs vorhanden → Exit 0."""
    errors = _run(tmp_config, _fake_success)
    assert errors == 0


def test_once_exit_0_when_all_success(tmp_config) -> None:
    """Szenario: Alle PDFs erfolgreich → Exit 0."""
    (tmp_config.paths.incoming / "a.pdf").write_bytes(b"%PDF-1.4\n")
    (tmp_config.paths.incoming / "b.pdf").write_bytes(b"%PDF-1.4\n")

    errors = _run(tmp_config, _fake_success)
    assert errors == 0


def test_once_exit_nonzero_when_all_fail(tmp_config) -> None:
    """Szenario: Alle PDFs fehlgeschlagen → Exit != 0 (Issue #2)."""
    (tmp_config.paths.incoming / "a.pdf").write_bytes(b"%PDF-1.4\n")
    (tmp_config.paths.incoming / "b.pdf").write_bytes(b"%PDF-1.4\n")

    errors = _run(tmp_config, _fake_failure)
    assert errors == 2


def test_once_exit_nonzero_when_some_fail(tmp_config) -> None:
    """Szenario: Teilweise fehlgeschlagen → Exit != 0."""
    (tmp_config.paths.incoming / "ok.pdf").write_bytes(b"%PDF-1.4\n")
    (tmp_config.paths.incoming / "bad.pdf").write_bytes(b"%PDF-1.4\n")

    def mixed(src, *args, **kwargs):
        if "bad" in src.name:
            return _fake_failure(src, *args, **kwargs)
        return _fake_success(src, *args, **kwargs)

    errors = _run(tmp_config, mixed)
    assert errors == 1


def test_counters_track_success_and_failure(tmp_config) -> None:
    """success_count und error_count sollen korrekt mitzählen."""
    (tmp_config.paths.incoming / "ok.pdf").write_bytes(b"%PDF-1.4\n")
    (tmp_config.paths.incoming / "bad.pdf").write_bytes(b"%PDF-1.4\n")

    def mixed(src, *args, **kwargs):
        if "bad" in src.name:
            return _fake_failure(src, *args, **kwargs)
        return _fake_success(src, *args, **kwargs)

    with patch("pdf_ocr_hotfolder.service.check_preflight", return_value=None), \
         patch("pdf_ocr_hotfolder.service.process_pdf", side_effect=mixed), \
         patch("pdf_ocr_hotfolder.service._wait_until_stable", return_value=True):
        service = HotfolderService(tmp_config)
        try:
            service.run_once()
            assert service.success_count == 1
            assert service.error_count == 1
        finally:
            service._executor.shutdown(wait=False)