"""Усиление опорного кадра проверяется двумя потерями в одном блоке."""

from __future__ import annotations

import json

from tools.video004_transport import (
    BASELINE_160, BASELINE_320, CODEC_RESULTS, _frames, simulate,
)


def test_double_keyframe_loss_needs_two_parity_symbols() -> None:
    codec = json.loads(CODEC_RESULTS.read_text(encoding="utf-8"))
    baseline = json.loads(BASELINE_320.read_text(encoding="utf-8"))
    baseline_160 = json.loads(BASELINE_160.read_text(encoding="utf-8"))
    combined, _ = _frames("NORMAL", 640, 360, 10, baseline["windows"][0],
                          codec, baseline_160)
    frames = [frame for frame in combined if frame.stream_id == 0x56303334]
    base = simulate(frames, 10, "2/3", 8, 1, ("keyframe_double", 2))
    boosted = simulate(frames, 10, "2/3", 8, 1, ("keyframe_double", 2),
                       keyframe_boost=True)
    assert base["displayed_frames"] == 55
    assert base["unrecoverable_blocks"] == 1
    assert boosted["displayed_frames"] == 60
    assert boosted["parity_recoveries"] == 2