from __future__ import annotations

import json
import sys
from datetime import datetime
from pathlib import Path
from types import SimpleNamespace

from src.people_flow.models import AttributeConfig
from src.people_flow.pipeline import PeopleFlowPipeline, resolve_inference_device


def test_resolve_inference_device_keeps_cpu():
    assert resolve_inference_device("cpu") == "cpu"


def test_resolve_inference_device_falls_back_when_cuda_unavailable(monkeypatch):
    fake_torch = SimpleNamespace(
        cuda=SimpleNamespace(is_available=lambda: False),
    )
    monkeypatch.setitem(sys.modules, "torch", fake_torch)

    assert resolve_inference_device("cuda:0") == "cpu"


def test_resolve_inference_device_keeps_cuda_when_available(monkeypatch):
    fake_torch = SimpleNamespace(
        cuda=SimpleNamespace(is_available=lambda: True),
    )
    monkeypatch.setitem(sys.modules, "torch", fake_torch)

    assert resolve_inference_device("cuda:0") == "cuda:0"


def test_attribute_config_defaults_to_disabled():
    assert AttributeConfig().enabled is False


def test_write_live_rtsp_summary_updates_latest_json(tmp_path: Path):
    pipeline = PeopleFlowPipeline.__new__(PeopleFlowPipeline)
    observed_at = datetime.fromisoformat("2026-05-18T10:45:18+08:00")
    window_start = datetime.fromisoformat("2026-05-18T10:30:00+08:00")

    def fake_build_rtsp_summary(**kwargs):
        return {
            "event": "half_hour_report",
            "window_start": kwargs["window_start"].isoformat(),
            "window_end": kwargs["window_end"].isoformat(),
            "total_people": 4,
            "queue_metrics": {"queue_level": "normal"},
        }

    pipeline._build_rtsp_summary = fake_build_rtsp_summary  # type: ignore[method-assign]
    latest_path = tmp_path / "latest.json"

    pipeline._write_live_rtsp_summary(
        latest_path=latest_path,
        source="rtsp://example",
        window_index=0,
        window_start=window_start,
        observed_at=observed_at,
        counter=None,
        attributes=SimpleNamespace(),
        queue_tracker=None,
    )

    payload = json.loads(latest_path.read_text(encoding="utf-8"))
    assert payload["event"] == "rtsp_live_summary"
    assert payload["window_status"] == "in_progress"
    assert payload["window_start"] == window_start.isoformat()
    assert payload["window_end"] == observed_at.isoformat()


def test_write_live_rtsp_summary_does_not_commit_queue_level(tmp_path: Path):
    pipeline = PeopleFlowPipeline.__new__(PeopleFlowPipeline)
    observed_at = datetime.fromisoformat("2026-05-18T10:45:18+08:00")
    window_start = datetime.fromisoformat("2026-05-18T10:30:00+08:00")
    captured: dict[str, object] = {}

    def fake_build_rtsp_summary(**kwargs):
        captured.update(kwargs)
        return {
            "event": "half_hour_report",
            "window_start": kwargs["window_start"].isoformat(),
            "window_end": kwargs["window_end"].isoformat(),
            "total_people": 4,
            "queue_metrics": {"queue_level": "normal"},
        }

    pipeline._build_rtsp_summary = fake_build_rtsp_summary  # type: ignore[method-assign]
    latest_path = tmp_path / "latest.json"

    pipeline._write_live_rtsp_summary(
        latest_path=latest_path,
        source="rtsp://example",
        window_index=0,
        window_start=window_start,
        observed_at=observed_at,
        counter=None,
        attributes=SimpleNamespace(),
        queue_tracker=SimpleNamespace(),
    )

    assert captured["commit_queue_level"] is False