"""Tests für Issue #1: Preflight-Check bei fehlendem Tesseract."""
from __future__ import annotations

import sys
from unittest.mock import patch

import pytest

from pdf_ocr_hotfolder.service import (
    HotfolderService,
    PreflightError,
    check_preflight,
)


def test_preflight_passes_when_all_binaries_present() -> None:
    """Wenn tesseract + gs im PATH sind, darf kein Fehler fliegen."""
    with patch("pdf_ocr_hotfolder.service.shutil.which", return_value="/usr/bin/fake"):
        check_preflight()  # darf nicht werfen


def test_preflight_fails_when_tesseract_missing() -> None:
    """Fehlendes tesseract → PreflightError mit passender Meldung."""
    def fake_which(name: str) -> str | None:
        return None if name == "tesseract" else "/usr/bin/fake"

    with patch("pdf_ocr_hotfolder.service.shutil.which", side_effect=fake_which):
        with pytest.raises(PreflightError, match="tesseract"):
            check_preflight()


def test_preflight_fails_when_ghostscript_missing() -> None:
    def fake_which(name: str) -> str | None:
        return None if name == "gs" else "/usr/bin/fake"

    with patch("pdf_ocr_hotfolder.service.shutil.which", side_effect=fake_which):
        with pytest.raises(PreflightError, match="gs"):
            check_preflight()


def test_preflight_lists_all_missing_binaries() -> None:
    """Bei mehreren fehlenden Binaries werden alle genannt."""
    with patch("pdf_ocr_hotfolder.service.shutil.which", return_value=None):
        with pytest.raises(PreflightError) as exc_info:
            check_preflight()
        msg = str(exc_info.value)
        assert "tesseract" in msg
        assert "gs" in msg


def test_run_once_raises_preflight_error(tmp_config) -> None:
    """HotfolderService.run_once() wirft PreflightError, wenn tesseract fehlt."""
    service = HotfolderService(tmp_config)
    try:
        with patch("pdf_ocr_hotfolder.service.shutil.which", return_value=None):
            with pytest.raises(PreflightError):
                service.run_once()
    finally:
        service._executor.shutdown(wait=False)


def test_main_returns_2_on_preflight_error(tmp_config, tmp_path, monkeypatch) -> None:
    """CLI liefert Exit-Code 2 bei Preflight-Fehler (Issue #1 Szenario)."""
    cfg_file = tmp_path / "cfg.toml"
    cfg_file.write_text(f"""
[paths]
incoming = "{tmp_config.paths.incoming}"
outgoing = "{tmp_config.paths.outgoing}"
working  = "{tmp_config.paths.working}"
error    = "{tmp_config.paths.error}"
""")
    monkeypatch.setattr(sys, "argv", ["pdf-ocr-hotfolder", "--config", str(cfg_file), "--once"])
    with patch("pdf_ocr_hotfolder.service.shutil.which", return_value=None):
        from pdf_ocr_hotfolder.__main__ import main
        assert main() == 2