"""Tests for the filename clock in isrweb/audiofile.py.

Recordings are named for their *start* time, and that name is the only
reliable time anchor the archive has — mtime drifts to the last write.
"""

from isrweb.audiofile import _cut_filename, _recording_start


def test_recording_start_parses_standard_name():
    from datetime import datetime
    assert _recording_start("20260523_220000") == datetime(2026, 5, 23, 22, 0, 0)


def test_recording_start_rejects_nonstandard_name():
    assert _recording_start("radio1_20260523") is None
    assert _recording_start("notes") is None


def test_cut_filename_uses_wall_clock_span():
    # Recording started 22:00:00; cut covers 22:31:30 → 22:32:30.
    name = _cut_filename("20260523_220000", ".flac", 1890, 1950)
    assert name == "20260523_22-31-30_22-32-30.flac"


def test_cut_filename_rolls_over_the_hour():
    name = _cut_filename("20260523_220000", ".wav", 3590, 3661)
    assert name == "20260523_22-59-50_23-01-01.wav"


def test_cut_filename_falls_back_for_nonstandard_name():
    name = _cut_filename("mixtape", ".mp3", 740, 750.4)
    assert name == "mixtape_cut_740s-750s.mp3"