from datetime import datetime
from zoneinfo import ZoneInfo

from src.people_flow.models import QueueConfig, TrackObservation
from src.people_flow.queue_analytics import QueueWindowTracker

TZ = ZoneInfo("Asia/Shanghai")


def test_queue_window_tracker_builds_crowded_report():
    tracker = QueueWindowTracker(
        QueueConfig(
            queue_time_threshold_seconds=300,
            crowded_count_threshold=5,
            normal_count_threshold=2,
            pause_timeout_seconds=5,
        ),
        pixel_area=(0, 0, 100, 100),
    )
    start = datetime(2026, 4, 15, 11, 0, tzinfo=TZ)
    crowded_tracks = [
        TrackObservation(
            track_id=index, bbox=(0, 0, 10, 10), confidence=0.9, center=(10, 10)
        )
        for index in range(1, 7)
    ]
    short_tracks = [
        TrackObservation(
            track_id=index, bbox=(0, 0, 10, 10), confidence=0.9, center=(10, 10)
        )
        for index in range(7, 9)
    ]

    tracker.observe(crowded_tracks, start)
    tracker.observe(crowded_tracks, start.replace(minute=6))
    tracker.observe(crowded_tracks + short_tracks, start.replace(minute=27))
    tracker.observe(short_tracks, start.replace(minute=30))

    queue_metrics = tracker.build_queue_metrics(start, start.replace(minute=30))

    assert queue_metrics["over_threshold_count"] == 6
    assert queue_metrics["under_threshold_count"] == 2
    assert queue_metrics["queue_level"] == "crowded"
    assert queue_metrics["queue_level_label"] == "人多"
    assert queue_metrics["previous_queue_level"] is None
    assert queue_metrics["previous_queue_level_label"] == ""
    assert queue_metrics["status_change"] == "initial"
    assert queue_metrics["status_change_label"] == "初始"


def test_live_preview_does_not_overwrite_previous_finalized_queue_level():
    tracker = QueueWindowTracker(
        QueueConfig(
            queue_time_threshold_seconds=60,
            crowded_count_threshold=3,
            normal_count_threshold=2,
            pause_timeout_seconds=5,
        ),
        pixel_area=(0, 0, 100, 100),
    )
    first_window_start = datetime(2026, 4, 15, 11, 0, tzinfo=TZ)
    first_window_end = datetime(2026, 4, 15, 11, 5, tzinfo=TZ)
    second_window_start = first_window_end
    second_window_preview = datetime(2026, 4, 15, 11, 7, tzinfo=TZ)
    second_window_end = datetime(2026, 4, 15, 11, 10, tzinfo=TZ)

    normal_tracks = [
        TrackObservation(
            track_id=index, bbox=(0, 0, 10, 10), confidence=0.9, center=(10, 10)
        )
        for index in range(1, 4)
    ]
    few_tracks = [
        TrackObservation(
            track_id=10, bbox=(0, 0, 10, 10), confidence=0.9, center=(10, 10)
        )
    ]

    tracker.observe(normal_tracks, first_window_start)
    tracker.observe(normal_tracks, first_window_end)
    first_metrics = tracker.build_queue_metrics(first_window_start, first_window_end)

    assert first_metrics["queue_level"] == "normal"
    assert first_metrics["status_change"] == "initial"

    tracker.reset()
    tracker.observe(few_tracks, second_window_start)
    tracker.observe([], second_window_preview)
    preview_metrics = tracker.build_queue_metrics(
        second_window_start,
        second_window_preview,
        commit_queue_level=False,
    )

    assert preview_metrics["queue_level"] == "few"
    assert preview_metrics["previous_queue_level"] == "normal"
    assert preview_metrics["status_change"] == "queue_decreased"

    final_metrics = tracker.build_queue_metrics(second_window_start, second_window_end)

    assert final_metrics["queue_level"] == "few"
    assert final_metrics["previous_queue_level"] == "normal"
    assert final_metrics["status_change"] == "queue_decreased"


def test_queue_level_is_normal_when_count_reaches_threshold():
    tracker = QueueWindowTracker(
        QueueConfig(
            queue_time_threshold_seconds=60,
            crowded_count_threshold=3,
            normal_count_threshold=2,
            pause_timeout_seconds=5,
        ),
        pixel_area=(0, 0, 100, 100),
    )
    start = datetime(2026, 4, 15, 11, 0, tzinfo=TZ)
    end = datetime(2026, 4, 15, 11, 5, tzinfo=TZ)
    tracks = [
        TrackObservation(
            track_id=index, bbox=(0, 0, 10, 10), confidence=0.9, center=(10, 10)
        )
        for index in range(1, 4)
    ]

    tracker.observe(tracks, start)
    tracker.observe(tracks, start.replace(minute=2))
    tracker.observe([], end)

    metrics = tracker.build_queue_metrics(start, end)

    assert metrics["over_threshold_count"] == 3
    assert metrics["queue_level"] == "normal"
    assert metrics["queue_level_label"] == "人数正常"