from unittest.mock import AsyncMock, MagicMock, patch

import pytest
from httpx import ASGITransport, AsyncClient

from app.main import app


@pytest.mark.asyncio
async def test_stats_zero_sessions() -> None:
    """Stats endpoint returns zeroed StatsResponse when no data exists."""
    mock_db = AsyncMock()

    with (
        patch("app.services.stats_service.count_active_sessions", return_value=0),
        patch("app.core.database.get_db", return_value=mock_db),
    ):
        # DB returns None for DailyStat row and empty for interest categories
        mock_db.scalar = AsyncMock(return_value=None)
        mock_db.scalars = AsyncMock(return_value=iter([]))

        async with AsyncClient(
            transport=ASGITransport(app=app), base_url="http://test"
        ) as client:
            response = await client.get("/stats")

    assert response.status_code == 200
    data = response.json()
    assert "active_sessions_now" in data
    assert "total_sessions_today" in data
    assert "total_matches_today" in data
    assert "top_interest_categories" in data
    assert data["active_sessions_now"] == 0
    assert data["total_sessions_today"] == 0
    assert data["total_matches_today"] == 0
    assert data["top_interest_categories"] == []


@pytest.mark.asyncio
async def test_stats_with_data() -> None:
    """Stats endpoint returns correct values when DailyStat row exists."""
    mock_stat = MagicMock()
    mock_stat.total_sessions = 12
    mock_stat.total_matches = 5

    mock_category = MagicMock()
    mock_category.category = "hiking"

    mock_db = AsyncMock()

    with (
        patch("app.services.stats_service.count_active_sessions", return_value=3),
        patch("app.core.database.get_db", return_value=mock_db),
    ):
        mock_db.scalar = AsyncMock(return_value=mock_stat)
        mock_db.scalars = AsyncMock(return_value=iter([mock_category]))

        async with AsyncClient(
            transport=ASGITransport(app=app), base_url="http://test"
        ) as client:
            response = await client.get("/stats")

    assert response.status_code == 200
    data = response.json()
    assert data["active_sessions_now"] == 3
    assert data["total_sessions_today"] == 12
    assert data["total_matches_today"] == 5
    assert data["top_interest_categories"] == ["hiking"]