import os

from fam_edge import frame_service
from fam_edge.frame_service import _bbox_to_pixels


def test_bbox_to_pixels_basic():
    # [ymin,xmin,ymax,xmax] 0-1000 归一化 -> 像素 (x1,y1,x2,y2)
    # 实测样本：Gemini 对 440x248 帧返回 [0, 690, 203, 725]，
    # 对应画面右上角门厅处的一个人（今天用真实截图验证过）。
    x1, y1, x2, y2 = _bbox_to_pixels([0, 690, 203, 725], 440, 248)
    assert x1 == int(690 / 1000 * 440)
    assert y1 == 0
    assert x2 == int(725 / 1000 * 440)
    assert y2 == int(203 / 1000 * 248)


def test_bbox_to_pixels_full_frame():
    x1, y1, x2, y2 = _bbox_to_pixels([0, 0, 1000, 1000], 400, 300)
    assert (x1, y1, x2, y2) == (0, 0, 400, 300)


def test_bbox_to_pixels_zero_area():
    x1, y1, x2, y2 = _bbox_to_pixels([500, 500, 500, 500], 400, 300)
    assert (x1, y1) == (x2, y2)


class _FakeRow(dict):
    """支持 row['key'] 访问的假 sqlite3.Row。"""
    def __getitem__(self, k):
        return dict.get(self, k)


class _FakeDb:
    def __init__(self, local_path, event_start_time):
        self._row = _FakeRow(local_path=local_path, event_start_time=event_start_time)

    def get_video_by_id(self, video_id):
        return self._row


def test_extract_frame_cache_key_includes_width(tmp_path, monkeypatch):
    """核心诉求: 同一 (video_id, ts) 不同调用方要不同分辨率（时间轴缩略图/头像/
    人物识别裁人脸），缓存 key 不带 width 会导致后来的高分辨率请求悄悄拿到早先
    缓存的低分辨率帧——这里验证两次不同 width 请求各自落到独立的缓存文件。"""
    monkeypatch.setattr(frame_service, "CACHE_DIR", str(tmp_path))
    video_path = tmp_path / "fake_video.mp4"
    video_path.write_bytes(b"not a real video, ffmpeg call is mocked")
    db = _FakeDb(str(video_path), "2026-08-22 10:00:00")

    written_widths = []

    def fake_run_ffmpeg(args, timeout=60):
        # 把请求的 -vf scale=WIDTH:-2 记下来，往输出路径写点假数据模拟成功
        out_path = args[-1]
        vf = next((a for a in args if a.startswith('scale=')), '')
        written_widths.append(vf)
        with open(out_path, 'wb') as f:
            f.write(b'\xff\xd8fakejpeg')
        return True

    monkeypatch.setattr(frame_service, "_run_ffmpeg", fake_run_ffmpeg)

    data_small = frame_service.extract_frame(db, 42, "2026-08-22 10:00:05", width=400)
    data_large = frame_service.extract_frame(db, 42, "2026-08-22 10:00:05", width=2880)

    assert data_small is not None and data_large is not None
    cache_files = sorted(os.listdir(tmp_path))
    frame_caches = [f for f in cache_files if f.startswith('frame_42_5_')]
    assert len(frame_caches) == 2, f"expected 2 distinct cache files, got {frame_caches}"
    assert 'frame_42_5_400.jpg' in frame_caches
    assert 'frame_42_5_2880.jpg' in frame_caches
    # 两次都真的各自调用了 ffmpeg（第二次没有因为撞到第一次的缓存而被跳过）
    assert len(written_widths) == 2