import pytest
from datetime import datetime, timedelta, timezone
from httpx import AsyncClient, ASGITransport
from app.main import app
from app.database import engine
from app.models import SQLModel

@pytest.fixture
async def setup_db():
    async with engine.begin() as conn:
        await conn.run_sync(SQLModel.metadata.drop_all)
        await conn.run_sync(SQLModel.metadata.create_all)

@pytest.mark.asyncio
async def test_list_sessions_date_only_filter(setup_db):
    # Test that passing a date (midnight) also works and includes the whole day
    target_date = datetime(2023, 10, 1, tzinfo=timezone.utc)
    other_date = datetime(2023, 10, 2, tzinfo=timezone.utc)
    
    async with AsyncClient(
        transport=ASGITransport(app=app), base_url="http://test"
    ) as ac:
        # 1. Create a session that starts LATER in the day on OTHER date (should be excluded)
        # We end it immediately to avoid 409s in the test
        start_time_other = other_date.replace(hour=20, minute=0)
        resp_other = await ac.post("/api/sessions", json={"start_time": start_time_other.isoformat()})
        assert resp_other.status_code == 201
        session_id_other = resp_other.json()["id"]
        await ac.patch(f"/api/sessions/{session_id_other}/end", json={"end_time": (start_time_other + timedelta(minutes=30)).isoformat()})
        
        # 2. Create a session that starts ON the target_date (should be included)
        start_time_target = target_date.replace(hour=20, minute=0)
        resp_target = await ac.post("/api/sessions", json={"start_time": start_time_target.isoformat()})
        assert resp_target.status_code == 201
        session_id_target = resp_target.json()["id"]
        await ac.patch(f"/api/sessions/{session_id_target}/end", json={"end_time": (start_time_target + timedelta(minutes=30)).isoformat()})
        
        # 3. Create a session that starts EARLIER on the target_date (should be included)
        start_time_early = target_date.replace(hour=2, minute=0)
        resp_early = await ac.post("/api/sessions", json={"start_time": start_time_early.isoformat()})
        assert resp_early.status_code == 201
        session_id_early = resp_early.json()["id"]
        await ac.patch(f"/api/sessions/{session_id_early}/end", json={"end_time": (start_time_early + timedelta(minutes=30)).isoformat()})
        
        # 4. Create a session that is on the OTHER date (should be excluded)
        start_time_other2 = other_date.replace(hour=2, minute=0)
        resp_other2 = await ac.post("/api/sessions", json={"start_time": start_time_other2.isoformat()})
        assert resp_other2.status_code == 201
        session_id_other2 = resp_other2.json()["id"]
        await ac.patch(f"/api/sessions/{session_id_other2}/end", json={"end_time": (start_time_other2 + timedelta(minutes=30)).isoformat()})

        # Query with to_date = target_date (midnight)
        # This should be expanded to 23:59:59 on target_date.
        # Should include the 2 sessions on target_date (target and early).
        # Should exclude the 2 sessions on other_date.
        to_date_str = target_date.strftime("%Y-%m-%d") # "2023-10-01"
        print(f"\nGET: to_date={to_date_str}")

        response = await ac.get(f"/api/sessions?to_date={to_date_str}")
        print(f"GET RESPONSE: {response.status_code}, body={response.json()}")
        
        assert response.status_code == 200
        sessions = response.json()["sessions"]
        
        # We expect exactly 2 sessions (the ones on target_date)
        assert len(sessions) == 2, f"Expected 2 sessions (the ones on {to_date_str}), but got {len(sessions)}. (Body: {response.json()})"
        for s in sessions:
            # Verify that the sessions returned are indeed from the target_date
            assert target_date.strftime("%Y-%m-%d") in s["start_time"]