"""SHM round-trip for portrait daemon with a fake mask."""
import time

import numpy as np

from frame_shm import LatestFrameReader, LatestFrameWriter, wait_for_ready
from portrait import bgr_to_i420, i420_nbytes, i420_to_bgr, person_present
from portrait_daemon import CamSlot, tick_once


def test_tick_blurs_bg_and_keeps_person(tmp_path):
    w, h = 64, 48
    bgr = np.zeros((h, w, 3), dtype=np.uint8)
    bgr[::3, :] = 255
    bgr[:, ::3] = 255
    bgr[8:40, 16:48] = (20, 200, 20)
    payload = bgr_to_i420(bgr)
    src = tmp_path / "raw" / "cam-01.i420"
    dst = tmp_path / "por" / "cam-01.i420"
    writer = LatestFrameWriter(str(src), w, h)
    writer.write(payload)
    mask = np.zeros((h, w), dtype=np.float32)
    mask[8:40, 16:48] = 1.0

    def infer(_bgr):
        return mask

    slot = CamSlot(
        identity="cam-01",
        width=w,
        height=h,
        reader=LatestFrameReader(str(src)),
        writer=LatestFrameWriter(str(dst), w, h),
        infer_hz=30.0,
        hold_s=0.8,
        blur_px=9,
    )
    n = tick_once([slot], infer, time.monotonic(), infer_budget_s=0.05)
    assert n == 1
    out_r = LatestFrameReader(str(dst))
    buf = bytearray(i420_nbytes(w, h))
    seq = out_r.copy_into(buf)
    assert seq == 1
    out = i420_to_bgr(buf, w, h)
    roi = out[12:36, 20:44]
    assert abs(int(roi[:, :, 1].mean()) - 200) < 25
    bg = out[0:6, :]
    assert float(bg.var()) < float(bgr[0:6, :].var()) * 0.6


def test_tick_blurs_when_empty(tmp_path):
    w, h = 32, 32
    bgr = np.zeros((h, w, 3), dtype=np.uint8)
    bgr[::3, :] = 255
    bgr[:, ::3] = 255
    payload = bgr_to_i420(bgr)
    src = tmp_path / "raw" / "cam-02.i420"
    dst = tmp_path / "por" / "cam-02.i420"
    LatestFrameWriter(str(src), w, h).write(payload)

    def infer(_bgr):
        return np.zeros((h, w), dtype=np.float32)

    slot = CamSlot(
        identity="cam-02",
        width=w,
        height=h,
        reader=LatestFrameReader(str(src)),
        writer=LatestFrameWriter(str(dst), w, h),
        infer_hz=30.0,
        hold_s=0.2,
        blur_px=9,
    )
    tick_once([slot], infer, time.monotonic(), infer_budget_s=0.05)
    buf = bytearray(i420_nbytes(w, h))
    assert LatestFrameReader(str(dst)).copy_into(buf) == 1
    y0 = np.frombuffer(payload, dtype=np.uint8, count=w * h).reshape(h, w)
    y1 = np.frombuffer(buf, dtype=np.uint8, count=w * h).reshape(h, w)
    assert float(y1.var()) < float(y0.var()) * 0.6
    assert person_present(np.zeros((h, w), dtype=np.float32)) is False


def test_wait_ready_helper(tmp_path):
    p = tmp_path / "ready"
    assert wait_for_ready(str(p), timeout=0.05) is False
    p.write_text("ok\n")
    assert wait_for_ready(str(p), timeout=0.2) is True