"""Tests for check_okf.py — the OKF v0.1 frontmatter validator.

Covers the control-character check added 2026-08-27: a file that otherwise has
valid frontmatter must still fail if its body contains a NUL byte or other
control byte outside \\t \\n \\r (the class of bug found in
kb/audits/wiki-kompilat-recon-2026-08-26.md — raw bytes pasted in from a psql
SELECT over the mail corpus).
"""
from __future__ import annotations

import sys
from pathlib import Path

sys.path.insert(0, str(Path(__file__).resolve().parents[1]))
import check_okf  # noqa: E402

VALID_FRONTMATTER = """---
okf: "0.1"
type: decision
visibility: private
status: active
updated: 2026-08-27
links: []
---
"""


def _write(tmp_path: Path, body: str) -> Path:
    p = tmp_path / "doc.md"
    p.write_text(VALID_FRONTMATTER + body, encoding="utf-8")
    return p


def test_clean_file_has_no_control_char_errors(tmp_path):
    path = _write(tmp_path, "# Title\n\nZwykła treść z \t tabulatorem i \r\n końcem linii.\n")
    errors = check_okf.check_file(path, tmp_path)
    assert errors == []


def test_nul_byte_in_body_is_flagged(tmp_path):
    path = _write(tmp_path, "# Title\n\nZawiera bajt NUL: \x00 w tym miejscu.\n")
    errors = check_okf.check_file(path, tmp_path)
    assert any("bajt kontrolny" in e and "0x0" in e for e in errors)


def test_control_char_error_reports_correct_line(tmp_path):
    body = "linia 1\nlinia 2\nzepsuta \x00 linia 3\nlinia 4\n"
    path = _write(tmp_path, body)
    errors = check_okf.check_file(path, tmp_path)
    control_errors = [e for e in errors if "bajt kontrolny" in e]
    assert len(control_errors) == 1
    # Frontmatter occupies 7 lines before the body starts.
    frontmatter_lines = VALID_FRONTMATTER.count("\n")
    expected_line = frontmatter_lines + 3
    assert f"w linii {expected_line}" in control_errors[0]


def test_multiple_control_chars_same_line_reported_once(tmp_path):
    path = _write(tmp_path, "para \x00 z dwoma \x00 bajtami na tej samej linii\n")
    errors = check_okf.check_file(path, tmp_path)
    control_errors = [e for e in errors if "bajt kontrolny" in e]
    assert len(control_errors) == 1