"""Sběr telemetrie z Modbus: Deye (střídač), Teltonika TeltoCharge (EV); TČ zatím placeholder."""

from __future__ import annotations

import asyncio
import logging
from datetime import datetime, timezone

import asyncpg
from app.ws_manager import manager

from zoneinfo import ZoneInfo

from services.modbus_client import get_modbus_client

_PRAGUE_TZ_NOTIFY = ZoneInfo("Europe/Prague")

logger = logging.getLogger(__name__)

#: Pool pro fire-and-forget akce mimo hlavní poll spojení (např. replan po
#: příjezdu EV). Nastavuje run_telemetry_loop_wrapper.
_BG_POOL: asyncpg.Pool | None = None


async def _on_ev_arrival(site_id: int, charger_code: str) -> None:
    """Okamžitý replan + export po příjezdu EV (jinak by se čekalo až na */15).

    Deferred importy: planning_engine/control_exporter importují control balík,
    který se importuje nezávisle — vyhýbáme se importnímu cyklu při startu.
    """
    if _BG_POOL is None:
        logger.warning("EV arrival: BG pool není k dispozici, čeká se na rolling tick")
        return
    try:
        from services.control_exporter import export_setpoints
        from services.planning_engine import run_rolling_replan

        async with _BG_POOL.acquire() as conn:
            # Tesla: skutečné SoC do session PŘED replanem (selhání nesmí blokovat plán)
            try:
                await _patch_session_from_tesla(site_id, charger_code, conn)
            except Exception:
                logger.exception(
                    "Tesla SoC fetch failed (site=%s, %s) — replan jede na defaultech",
                    site_id, charger_code,
                )
            await run_rolling_replan(
                site_id, conn, triggered_by=f"ev_arrival:{charger_code}"
            )
            await export_setpoints(site_id, conn)
            try:
                from services.ev_notify import send_ev_arrival

                await send_ev_arrival(site_id, charger_code, conn)
            except Exception:
                logger.exception("EV arrival Discord notify failed (%s)", charger_code)
        logger.info(
            "EV arrival replan+export done (site=%s, charger=%s)",
            site_id,
            charger_code,
        )
    except Exception:
        logger.exception(
            "EV arrival replan failed (site=%s, charger=%s)", site_id, charger_code
        )


async def _on_ev_departure(site_id: int, charger_code: str) -> None:
    """Odjezd: zapsat pozorování (odometer+SoC) — auto právě jede, je vzhůru.

    Pár odjezd→příjezd dává jízdu (km, kWh) pro ev_usage_stats. Spící/nečitelné
    auto (408) = tiché přeskočení, jízda se dopočítá z příštích pozorování.
    """
    if _BG_POOL is None:
        return
    try:
        from app.db_json import fetch_json
        from services.tesla_client import get_charge_state

        async with _BG_POOL.acquire() as conn:
            ctx = await fetch_json(
                conn,
                "select ems.fn_tesla_arrival_context($1::int, $2::text)",
                site_id,
                charger_code,
            )
            if not isinstance(ctx, dict) or ctx.get("api_type") != "tesla":
                return
            state = await get_charge_state(conn, ctx.get("vin"))
            if state is None:
                return
            await conn.execute(
                "select ems.fn_ev_vehicle_obs_insert($1::int, $2::int, 'departure', $3::numeric, $4::numeric, $5::text)",
                site_id,
                int(ctx["vehicle_id"]),
                state.get("odometer_km"),
                float(state["battery_level"]),
                state.get("charging_state"),
            )
            logger.info(
                "EV departure obs (site=%s, %s): soc=%s%%, odo=%s km",
                site_id, charger_code,
                state["battery_level"], state.get("odometer_km"),
            )
    except Exception:
        logger.exception(
            "EV departure obs failed (site=%s, %s)", site_id, charger_code
        )


async def _patch_session_from_tesla(
    site_id: int, charger_code: str, conn: asyncpg.Connection
) -> None:
    """Po příjezdu: pro vozidlo s api_type='tesla' doplnit reálné SoC do session.

    Energie se NEpočítá tady — soc_at_connect_pct + target_soc_pct si přebere
    fn_planning_site_context (SQL-first). VIN se při prvním úspěchu naučí.
    """
    from app.db_json import fetch_json
    from services.tesla_client import get_charge_state

    ctx = await fetch_json(
        conn,
        "select ems.fn_tesla_arrival_context($1::int, $2::text)",
        site_id,
        charger_code,
    )
    if not isinstance(ctx, dict) or ctx.get("api_type") != "tesla":
        return
    session_id = ctx.get("session_id")
    if session_id is None:
        logger.warning("Tesla hook: chybí otevřená session (%s)", charger_code)
        return

    state = await get_charge_state(conn, ctx.get("vin"))
    if state is None:
        return

    await conn.execute(
        "select ems.fn_ev_vehicle_obs_insert($1::int, $2::int, 'arrival', $3::numeric, $4::numeric, $5::text)",
        site_id,
        int(ctx["vehicle_id"]),
        state.get("odometer_km"),
        float(state["battery_level"]),
        state.get("charging_state"),
    )

    if not ctx.get("vin") and state.get("vin"):
        await conn.execute(
            "select ems.fn_vehicle_set_vin($1::int, $2::text)",
            int(ctx["vehicle_id"]),
            str(state["vin"]),
        )

    patch: dict = {"soc_at_connect_pct": state["battery_level"]}
    if state.get("charge_limit_soc"):
        patch["target_soc_pct"] = state["charge_limit_soc"]
    import json as _json
    await fetch_json(
        conn,
        "select ems.fn_ev_session_apply_patch($1::int, $2::int, $3::jsonb)",
        site_id,
        int(session_id),
        _json.dumps(patch),
    )
    logger.info(
        "Tesla SoC -> session %s: level=%s%%, limit=%s%% (%s)",
        session_id,
        state["battery_level"],
        state.get("charge_limit_soc"),
        charger_code,
    )

# Deye SUN – holding registry (decimal adresa = přímo pro read_holding_registers)
DEYE_REG_RUN_STATE = 500
DEYE_REG_BATT_CHARGE_TODAY = 514
DEYE_REG_BATT_DISCHARGE_TODAY = 515
DEYE_REG_BATTERY_SOC = 588
DEYE_REG_BATTERY_POWER_FLOW = 590
DEYE_REG_GRID_TOTAL_POWER = 625
DEYE_REG_GEN_PORT_POWER = 667
DEYE_REG_LOAD_TOTAL_POWER = 653
DEYE_REG_GRID_IMPORT_TOTAL_LO = 522
DEYE_REG_GRID_IMPORT_TOTAL_HI = 523
DEYE_REG_GRID_EXPORT_TOTAL_LO = 524
DEYE_REG_GRID_EXPORT_TOTAL_HI = 525
DEYE_REG_PV1_POWER = 672
DEYE_REG_PV2_POWER = 673
# Solar sell (0 = přebytek řiditelné FVE nesmí do sítě) a GEN/MI cut-off (reg178 bits0–1 == 3 → cut-off ON).
# Pozn.: v některých manuálech/UI se uvádí "register 179" (1-based), ale Modbus adresa je 178 (0-based).
# Viz modbus-registers.md.
DEYE_REG_SOLAR_SELL = 145
DEYE_REG_CONTROL_BOARD_SPECIAL1 = 178

# Teltonika TeltoCharge – holding registry (oficiální „Modbus RTU Communication
# protocol" rev 0.5, 2024-07-23; přes Waveshare RS485→TCP, FC 3 čtení).
# Blok 0–40: 0–2 napětí L1–L3 (V), 3–5 proud L1–L3 (×10 A), 6 EVSE status (DLM),
# 27 charge point state, 33 IEC61851, 34/35 warning/error bity,
# 38 okamžitý výkon (W), 39 energie session (kWh×100), 40 trvání session (s).
# Zápisové (řízení, zatím nepoužité): 15 Amps to use (0=stop, 6–32), 16 start/stop.
TELTO_REG_BLOCK_START = 0
TELTO_REG_BLOCK_COUNT = 41

#: EVSE status (reg 6) → interní stav; session detekce stojí na 'available' vs ≠'available'
#: (fn_ev_session_transition), proto každý stav s připojeným EV musí být ≠ 'available'.
TELTO_STATUS_MAP = {
    0: "charging",        # C  – nabíjí
    1: "preparing",       # B1 – EV připojeno, čeká na EV
    2: "preparing",       # B2 – dříve nabíjelo, nedostatek výkonu
    3: "preparing",       # B3 – nenabíjelo, nedostatek výkonu
    4: "suspended_ev",    # D1 – zastaveno vozidlem
    5: "suspended_evse",  # D2 – bez autorizace
    6: "suspended_evse",  # D3 – nabíjení nepovoleno
    7: "available",       # A  – bez EV
    8: "faulted",         # F  – chyba
    9: "unknown",         # E
}


def parse_teltocharge_frame(regs: list[int]) -> dict[str, object]:
    """Čistý parser bloku registrů 0–40 TeltoCharge (testovatelné bez Modbus)."""
    if len(regs) < TELTO_REG_BLOCK_COUNT:
        raise ValueError(f"TeltoCharge frame too short: {len(regs)}")
    status = TELTO_STATUS_MAP.get(int(regs[6]), "unknown")
    current_a = max(int(regs[3]), int(regs[4]), int(regs[5])) / 10.0
    return {
        "status": status,
        "power_w": int(regs[38]),
        "session_energy_kwh": int(regs[39]) / 100.0,
        "current_a": current_a,
        "voltage_v": int(regs[0]),
        "warning_bits": int(regs[34]),
        "error_bits": int(regs[35]),
        "evse_status_raw": int(regs[6]),
        "charge_point_state_raw": int(regs[27]),
    }


def aggregate_pv_production_w(pv1_w: int, pv2_w: int, gen_port_w: int) -> int:
    """
    Okamžitá „výroba FVE“ pro dashboard / audit součtu: Deye registry 672/673/667
    jsou int16 W; záporné hodnoty (např. večer při exportu) nejsou DC výroba.
    """
    return max(0, int(pv1_w)) + max(0, int(pv2_w)) + max(0, int(gen_port_w))


def _export_limit_flags_from_deye_regs(reg145: int | None, reg179: int | None) -> tuple[bool | None, int | None]:
    """Odvoď is_export_limited / pv_derating_flags z přečtených holding registrů (NULL = neznámé)."""
    if reg145 is None and reg179 is None:
        return None, None
    flags = 0
    if reg145 is not None and int(reg145) == 0:
        flags |= 1
    if reg179 is not None and (int(reg179) & 3) == 3:
        flags |= 2
    return (flags != 0), flags


async def poll_inverter(site_id: int, db: asyncpg.Connection) -> None:
    rows = await db.fetch(
        """
        select inverter_id as id, code, host, port, unit_id
        from ems.vw_asset_inverter_modbus_poll
        where site_id = $1
        """,
        site_id,
    )
    measured_at = datetime.now(timezone.utc)
    for row in rows:
        inv_id = row["id"]
        code = row["code"]
        host = row["host"]
        port = int(row["port"] or 502)
        unit_id = int(row["unit_id"] if row["unit_id"] is not None else 1)
        try:
            client = await get_modbus_client(host, port)
            async with client.batch(unit_id) as mb:
                run_state = await mb.read_register(DEYE_REG_RUN_STATE)
                battery_soc = await mb.read_register(DEYE_REG_BATTERY_SOC)
                battery_power = await mb.read_register_signed(DEYE_REG_BATTERY_POWER_FLOW)
                batt_charge_today = await mb.read_register(DEYE_REG_BATT_CHARGE_TODAY)
                batt_discharge_today = await mb.read_register(DEYE_REG_BATT_DISCHARGE_TODAY)
                grid_power = await mb.read_register_signed(DEYE_REG_GRID_TOTAL_POWER)
                load_power = await mb.read_register_signed(DEYE_REG_LOAD_TOTAL_POWER)
                pv1_power = await mb.read_register_signed(DEYE_REG_PV1_POWER)
                pv2_power = await mb.read_register_signed(DEYE_REG_PV2_POWER)
                gen_port_power = await mb.read_register_signed(DEYE_REG_GEN_PORT_POWER)
                grid_energy_regs = await mb.read_holding_registers(
                    DEYE_REG_GRID_IMPORT_TOTAL_LO, 4
                )
                reg145 = await mb.read_register(DEYE_REG_SOLAR_SELL)
                reg179 = await mb.read_register(DEYE_REG_CONTROL_BOARD_SPECIAL1)
            pv_power_w = aggregate_pv_production_w(pv1_power, pv2_power, gen_port_power)
            grid_import_total_wh = (grid_energy_regs[1] << 16 | grid_energy_regs[0]) * 100
            grid_export_total_wh = (grid_energy_regs[3] << 16 | grid_energy_regs[2]) * 100
            is_export_limited, pv_derating_flags = _export_limit_flags_from_deye_regs(reg145, reg179)

            logger.debug("inverter:%s Deye run_state raw=%s", code, run_state)

            await db.execute(
                "select ems.fn_telemetry_inverter_sample($1::int, $2::int, $3::timestamptz, $4::int, $5::int, $6::int, $7::int, $8::float8, $9::int, $10::int, $11::int, $12::int, $13::int, $14::bigint, $15::bigint, $16::int, $17::boolean, $18::int)",
                site_id,
                inv_id,
                measured_at,
                pv_power_w,
                pv1_power,
                pv2_power,
                gen_port_power,
                float(battery_soc),
                battery_power,
                batt_charge_today,
                batt_discharge_today,
                grid_power,
                load_power,
                grid_import_total_wh,
                grid_export_total_wh,
                run_state,
                is_export_limited,
                pv_derating_flags,
            )
            inv_temp: float | None = None
            await manager.broadcast_telemetry(
                {
                    "type": "telemetry",
                    "site_id": site_id,
                    "ts": datetime.now(timezone.utc).isoformat(),
                    "pv_power_w": pv_power_w,
                    "battery_soc_pct": float(battery_soc),
                    "battery_power_w": battery_power,
                    "grid_power_w": grid_power,
                    "load_power_w": load_power,
                    "gen_port_power_w": gen_port_power,
                    "inverter_temp_c": inv_temp,
                    "is_export_limited": is_export_limited,
                    "pv_derating_flags": pv_derating_flags,
                }
            )
        except Exception as e:
            logger.error("poll_inverter site=%s inverter=%s: %s", site_id, code, e)


async def poll_ev_chargers(site_id: int, db: asyncpg.Connection) -> None:
    rows = await db.fetch(
        """
        select charger_id as id, code, host, port, unit_id
        from ems.vw_asset_ev_charger_modbus_poll
        where site_id = $1
        """,
        site_id,
    )
    measured_at = datetime.now(timezone.utc)
    connector_id = 1
    for row in rows:
        code = row["code"]
        charger_id = row["id"]
        host = row["host"]
        port = int(row["port"] or 502)
        unit_id = int(row["unit_id"] if row["unit_id"] is not None else 1)

        try:
            client = await get_modbus_client(host, port)
            async with client.batch(unit_id) as mb:
                regs = await mb.read_holding_registers(
                    TELTO_REG_BLOCK_START, TELTO_REG_BLOCK_COUNT
                )
            frame = parse_teltocharge_frame(regs)
        except Exception as e:
            # Při výpadku čtení NIC nezapisovat — fabrikovaný 'available' by
            # falešně ukončoval EV session a špinil bazál (power 0).
            logger.warning("EV charger %s (%s:%s) read failed: %s", code, host, port, e)
            continue

        current_status = str(frame["status"])
        if frame["error_bits"]:
            logger.warning(
                "EV charger %s error bits=0x%04x warning=0x%04x",
                code, frame["error_bits"], frame["warning_bits"],
            )

        previous_status = await db.fetchval(
            """
            select status
            from ems.telemetry_ev_charger
            where charger_id = $1 and connector_id = $2
            order by measured_at desc
            limit 1
            """,
            charger_id,
            connector_id,
        )

        await db.execute(
            "select ems.fn_telemetry_ev_charger_sample($1::int, $2::int, $3::timestamptz, $4::int, $5::text, $6::int, $7::float8, $8::float8)",
            site_id,
            charger_id,
            measured_at,
            connector_id,
            current_status,
            int(frame["power_w"]),
            float(frame["session_energy_kwh"]),
            float(frame["current_a"]),
        )

        if previous_status is not None:
            await db.fetchval(
                "select ems.fn_ev_session_transition($1::int, $2::int, $3::text, $4::text, $5::timestamptz)",
                site_id,
                charger_id,
                str(previous_status),
                current_status,
                measured_at,
            )
            if previous_status == "available" and current_status != "available":
                logger.info("EV arrival detected on charger %s", code)
                asyncio.create_task(_on_ev_arrival(site_id, str(code)))
            elif previous_status != "available" and current_status == "available":
                logger.info("EV departure detected on charger %s", code)
                asyncio.create_task(_on_ev_departure(site_id, str(code)))


async def poll_heat_pump(site_id: int, db: asyncpg.Connection) -> None:
    rows = await db.fetch(
        """
        select heat_pump_id as id, code, host, port, unit_id
        from ems.vw_asset_heat_pump_modbus_poll
        where site_id = $1
        """,
        site_id,
    )
    measured_at = datetime.now(timezone.utc)
    for row in rows:
        code = row["code"]
        logger.info("TODO: heat pump Modbus registry pending (heat_pump=%s)", code)
        await db.execute(
            "select ems.fn_telemetry_heat_pump_sample($1::int, $2::int, $3::timestamptz, $4::int, $5::float8, $6::float8, $7::float8, $8::text)",
            site_id,
            row["id"],
            measured_at,
            0,
            10.0,
            45.0,
            55.0,
            "standby",
        )


async def poll_loxone_sensors(site_id: int, db: asyncpg.Connection) -> None:
    """Čidla z Loxone (teplota bazénu, akumulační nádrže…): GET /jdev/sps/io/<name>/state.

    Endpoint = site loxone_http; auth LOXONE_USER/PASSWORD (env). Hodnota
    z LL.value ("23.5°" → 23.5). Bez čidel v ems.loxone_sensor no-op.
    """
    rows = await db.fetch(
        """
        select ls.id, ls.loxone_name, se.host, se.port, se.protocol
        from ems.loxone_sensor ls
        join ems.site_endpoint se
          on se.site_id = ls.site_id and se.endpoint_type = 'loxone_http' and se.enabled
        where ls.site_id = $1 and ls.enabled
        """,
        site_id,
    )
    if not rows:
        return
    import os
    import re as _re

    import httpx

    auth = None
    user = os.getenv("LOXONE_USER") or ""
    if user:
        auth = (user, os.getenv("LOXONE_PASSWORD") or "")
    measured_at = datetime.now(timezone.utc)
    async with httpx.AsyncClient(timeout=5.0, auth=auth) as client:
        for r in rows:
            proto = (r["protocol"] or "http").lower()
            port = int(r["port"] or (443 if proto == "https" else 80))
            url = f"{proto}://{r['host']}:{port}/jdev/sps/io/{r['loxone_name']}/state"
            try:
                resp = await client.get(url)
                resp.raise_for_status()
                raw = str((resp.json().get("LL") or {}).get("value", ""))
                m = _re.search(r"-?\d+(?:[.,]\d+)?", raw)
                if m is None:
                    continue
                value = float(m.group(0).replace(",", "."))
            except Exception as e:
                logger.warning("Loxone sensor %s read failed: %s", r["loxone_name"], e)
                continue
            await db.execute(
                """
                insert into ems.telemetry_loxone_sensor (sensor_id, measured_at, value)
                values ($1, $2, $3) on conflict do nothing
                """,
                int(r["id"]),
                measured_at,
                value,
            )


#: presence poll pacing (sekundy) a geofence poloměr (m)
EV_PRESENCE_POLL_S = 300
EV_PRESENCE_HOME_RADIUS_M = 150
#: anti-spam "píchni auto": min. rozestup notifikací per vozidlo (s)
EV_PLUG_NUDGE_COOLDOWN_S = 2 * 3600
_EV_PRESENCE_LAST_POLL: dict[int, float] = {}
_EV_PLUG_NUDGE_LAST: dict[int, float] = {}


def ev_presence_transition(prev_at_home: bool | None, new_at_home: bool | None) -> str | None:
    """Čistá detekce přechodu: 'arrived' / 'left' / None (testovatelné)."""
    if new_at_home is None or prev_at_home is None:
        return None
    if not prev_at_home and new_at_home:
        return "arrived"
    if prev_at_home and not new_at_home:
        return "left"
    return None


async def poll_tesla_presence(site_id: int, db: asyncpg.Connection) -> None:
    """Přítomnost vozidla: /vehicles state (nebudí) + při online poloha → geofence.

    Přechod pryč→doma + nepíchnuté → Discord pobídka (s aktuálním přebytkem).
    Vše se loguje do ev_presence_obs (budoucí dostupnostní statistika).
    """
    loop_now = asyncio.get_running_loop().time()
    if loop_now - _EV_PRESENCE_LAST_POLL.get(site_id, 0.0) < EV_PRESENCE_POLL_S:
        return
    _EV_PRESENCE_LAST_POLL[site_id] = loop_now

    veh = await db.fetchrow(
        """
        select v.id, v.vin, v.name, s.latitude, s.longitude
        from ems.asset_vehicle v join ems.site s on s.id = v.site_id
        where v.site_id = $1 and v.api_type = 'tesla' and v.active
        order by v.id limit 1
        """,
        site_id,
    )
    if veh is None or veh["latitude"] is None:
        return

    from services.tesla_client import get_charge_state, get_vehicle_api_state, haversine_m

    try:
        api_state = await get_vehicle_api_state(db, veh["vin"])
    except Exception as e:
        logger.warning("Tesla presence: state poll failed: %s", e)
        return
    if api_state is None:
        return

    at_home = None
    distance_m = None
    charging_state = None
    shift_state = None
    if api_state == "online":
        try:
            st = await get_charge_state(db, veh["vin"])
        except Exception as e:
            logger.warning("Tesla presence: data read failed: %s", e)
            st = None
        if st is not None and st.get("latitude") is not None:
            distance_m = int(
                haversine_m(
                    float(st["latitude"]), float(st["longitude"]),
                    float(veh["latitude"]), float(veh["longitude"]),
                )
            )
            at_home = distance_m <= EV_PRESENCE_HOME_RADIUS_M
            charging_state = st.get("charging_state")
            shift_state = st.get("shift_state")

    prev = await db.fetchrow(
        """
        select at_home from ems.ev_presence_obs
        where vehicle_id = $1 and at_home is not null
        order by observed_at desc limit 1
        """,
        int(veh["id"]),
    )
    await db.execute(
        """
        insert into ems.ev_presence_obs
          (vehicle_id, api_state, at_home, distance_m, charging_state, shift_state)
        values ($1, $2, $3, $4, $5, $6)
        """,
        int(veh["id"]), api_state, at_home, distance_m, charging_state, shift_state,
    )

    trans = ev_presence_transition(prev["at_home"] if prev else None, at_home)
    if trans == "arrived" and charging_state == "Disconnected":
        if loop_now - _EV_PLUG_NUDGE_LAST.get(int(veh["id"]), 0.0) < EV_PLUG_NUDGE_COOLDOWN_S:
            return
        _EV_PLUG_NUDGE_LAST[int(veh["id"])] = loop_now
        grid_w = await db.fetchval(
            "select grid_power_w from ems.vw_latest_inverter where site_id = $1 limit 1",
            site_id,
        )
        surplus = f" — právě teče {abs(int(grid_w))/1000:.1f} kW do sítě" if grid_w and grid_w < -500 else ""
        from services.notification_service import send_discord

        await send_discord(
            db, site_id,
            f"🚗 **{veh['name'] or 'EV'} je doma a nepíchnuté**{surplus}.\n"
            f"Píchni ho a plán se o zbytek postará (přebytky / levné sloty).",
            level="info",
        )
        logger.info("EV plug nudge sent (site=%s, vehicle=%s)", site_id, veh["id"])


async def run_telemetry_loop(conn: asyncpg.Connection) -> float:
    """Jeden průchod smyčky; vrátí uplynulý čas v sekundách (pro sleep).

    Poll probíhá sekvenčně — jedno asyncpg spojení nesmí obsluhovat paralelní dotazy.
    """
    loop = asyncio.get_running_loop()
    start = loop.time()
    sites = await conn.fetch(
        "select id from ems.vw_site_directory where active = true"
    )
    for site in sites:
        sid = site["id"]
        try:
            await poll_inverter(sid, conn)
            await poll_ev_chargers(sid, conn)
            await poll_heat_pump(sid, conn)
            await poll_loxone_sensors(sid, conn)
            await poll_tesla_presence(sid, conn)
            await poll_pool_pumps(sid, conn)
        except Exception as e:
            logger.error("Telemetry loop error site %s: %s", sid, e)
    return loop.time() - start


async def run_telemetry_loop_wrapper(pool: asyncpg.Pool) -> None:
    """Background task: každá iterace získá spojení z poolu; neblokuje pool během sleep."""
    global _BG_POOL
    _BG_POOL = pool
    while True:
        try:
            async with pool.acquire() as conn:
                elapsed = await run_telemetry_loop(conn)
        except asyncio.CancelledError:
            raise
        except Exception as e:
            logger.exception("Telemetry wrapper DB error: %s", e)
            elapsed = 0.0
            await asyncio.sleep(5)
            continue

        if elapsed > 50:
            logger.warning("Telemetry loop took %.1fs (>50s)", elapsed)
        await asyncio.sleep(max(0.0, 60.0 - elapsed))


async def poll_pool_pumps(site_id: int, db: asyncpg.Connection) -> None:
    """Poll bazénových čerpadel přes Shelly relé (Gen2 RPC Switch.GetStatus), 60 s.

    Shelly nedrží historii — stavíme ji 1min vzorky jako u ostatních zařízení.
    """
    # Lokální import: minimální dotyk hlavičky souboru (souběžné změny na main).
    from services.shelly_client import get_switch_status, shelly_base_url

    rows = await db.fetch(
        """
        select pump_id as id, code, shelly_switch_id, protocol, host, port
        from ems.vw_asset_pool_pump_http_poll
        where site_id = $1
        """,
        site_id,
    )
    measured_at = datetime.now(timezone.utc)
    for row in rows:
        code = row["code"]
        base = shelly_base_url(row["protocol"], row["host"], row["port"])
        try:
            status = await get_switch_status(base, int(row["shelly_switch_id"] or 0))
        except Exception as e:
            # Při výpadku čtení NIC nezapisovat — fabrikovaná nula by špinila
            # historii spotřeby (stejný princip jako u EV nabíječek výše).
            logger.warning("pool pump %s (%s) read failed: %s", code, base, e)
            continue

        await db.execute(
            "select ems.fn_telemetry_pool_pump_sample($1::int, $2::int, $3::timestamptz, $4::boolean, $5::int, $6::bigint)",
            site_id,
            row["id"],
            measured_at,
            status.output,
            int(round(status.apower_w)) if status.apower_w is not None else None,
            int(round(status.aenergy_total_wh)) if status.aenergy_total_wh is not None else None,
        )