tests/test_segmentation.py

"""Tests for segmentation."""

from __future__ import annotations

from pathlib import Path

from video_vec2wav2_tokenizer.audio.extractor import load_wav
from video_vec2wav2_tokenizer.segmentation.segmenter import Segmenter, normalize_segments
from video_vec2wav2_tokenizer.utils.io import Segment


def test_normalize_drops_short_segments() -> None:
    segs = [Segment(0.0, 0.4, "tiny"), Segment(1.0, 3.0, "ok")]
    out = normalize_segments(segs, min_length=1.0, max_length=20.0)
    assert len(out) == 1
    assert out[0].text == "ok"


def test_normalize_splits_long_segments() -> None:
    segs = [Segment(0.0, 50.0, "long")]
    out = normalize_segments(segs, min_length=1.0, max_length=20.0)
    assert len(out) == 3  # ceil(50/20)
    assert out[0].text == "long"
    assert out[1].text == ""  # text not duplicated
    assert all(s.duration <= 20.0 + 1e-6 for s in out)


def test_normalize_padding_clamped() -> None:
    segs = [Segment(0.0, 2.0, "x")]
    out = normalize_segments(segs, min_length=0.5, max_length=20.0, padding=1.0, total_duration=2.5)
    assert out[0].start == 0.0           # clamped at 0
    assert out[0].end == 2.5             # clamped at total_duration


def test_segment_file_writes_clips(sine_wav: Path, tmp_path: Path) -> None:
    segs = [Segment(0.0, 1.0, "a"), Segment(1.0, 2.0, "b")]
    segmenter = Segmenter(sample_rate=16000)
    out_dir = tmp_path / "clips"
    results = segmenter.segment_file(sine_wav, segs, out_dir, start_index=1)

    assert [p.name for p, _ in results] == ["000001.wav", "000002.wav"]
    samples, sr = load_wav(results[0][0])
    assert sr == 16000
    assert abs(samples.shape[0] - 16000) < 10  # ~1 second


def test_segment_index_continues(sine_wav: Path, tmp_path: Path) -> None:
    segs = [Segment(0.0, 1.0, "a")]
    segmenter = Segmenter(sample_rate=16000)
    out_dir = tmp_path / "clips"
    r1 = segmenter.segment_file(sine_wav, segs, out_dir, start_index=5)
    assert r1[0][0].name == "000005.wav"