from fastapi import APIRouter, Depends, Query
from sqlalchemy import text
from sqlalchemy.ext.asyncio import AsyncSession
from core.database import get_session

router = APIRouter()

# Static topology metadata — mirrors simulator config
LEAK_SENSORS = {
    "sg-01": [
        {"sensor_id": "leak-01", "floor_zone": "crac-zone-a",   "under_floor": True,  "near_crac": True,  "room_id": "hall-a"},
        {"sensor_id": "leak-02", "floor_zone": "server-row-b1", "under_floor": True,  "near_crac": False, "room_id": "hall-b"},
        {"sensor_id": "leak-03", "floor_zone": "ups-room",      "under_floor": False, "near_crac": False, "room_id": None},
    ]
}


@router.get("/status")
async def leak_status(
    site_id: str = Query(...),
    session: AsyncSession = Depends(get_session),
):
    """Latest state for all leak sensors, enriched with location metadata."""
    result = await session.execute(text("""
        SELECT DISTINCT ON (sensor_id)
            sensor_id, value, recorded_at
        FROM readings
        WHERE site_id     = :site_id
          AND sensor_type = 'leak'
          AND recorded_at > NOW() - INTERVAL '5 minutes'
        ORDER BY sensor_id, recorded_at DESC
    """), {"site_id": site_id})

    # sensor_id format: {site_id}/leak/{sensor_id}
    state_map: dict[str, dict] = {}
    for row in result.mappings().all():
        parts = row["sensor_id"].split("/")
        if len(parts) < 3:
            continue
        sid = parts[2]
        state_map[sid] = {
            "state":       "detected" if float(row["value"]) > 0.5 else "clear",
            "recorded_at": str(row["recorded_at"]),
        }

    out = []
    for cfg in LEAK_SENSORS.get(site_id, []):
        sid = cfg["sensor_id"]
        entry = {**cfg}
        if sid in state_map:
            entry["state"]       = state_map[sid]["state"]
            entry["recorded_at"] = state_map[sid]["recorded_at"]
        else:
            entry["state"]       = "unknown"
            entry["recorded_at"] = None
        out.append(entry)
    return out