Discord bot fáze B: tlačítka na EV zprávě → patch session + okamžitý replan

services/discord_bot.py: gateway klient jako lifespan task (spojení ven,
žádný veřejný endpoint; bez DISCORD_BOT_TOKEN tiše spí). Tlačítka
[za 2h][za 4h][ráno][do plna][nenabíjet] s custom_id ev:<site>:<charger>:<akce>
(přežijí restart); whitelist DISCORD_ALLOWED_USER_IDS; akce = fn_ev_session_
apply_patch → run_rolling_replan → export_setpoints → edit zprávy novým plánem.

services/ev_notify.py: sdílený builder souhrnu (vyčleněno z collectoru),
send bot-first s webhook fallbackem. requirements: discord.py>=2.4.
7 testů helperů (parse, deadline akce vč. morning přes Prague TZ).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

backend/services/ev_notify.py

@@ -0,0 +1,115 @@
+"""Souhrn EV nabíjecího plánu pro notifikace (Discord webhook i bot).
+
+Sdílené mezi telemetry_collector (zpráva po příjezdu) a discord_bot
+(přestavba zprávy po akci tlačítkem).
+"""
+
+from __future__ import annotations
+
+import logging
+from zoneinfo import ZoneInfo
+
+import asyncpg
+
+logger = logging.getLogger(__name__)
+
+_PRAGUE = ZoneInfo("Europe/Prague")
+
+
+async def get_open_session(
+    site_id: int, charger_code: str, conn: asyncpg.Connection
+) -> asyncpg.Record | None:
+    return await conn.fetchrow(
+        """
+        select es.id as session_id, es.soc_at_connect_pct, es.target_soc_pct,
+               es.target_deadline, v.battery_capacity_kwh, v.name as vehicle_name,
+               v.default_deadline_hour
+        from ems.ev_session es
+        join ems.asset_ev_charger c on c.id = es.charger_id
+        left join ems.asset_vehicle v on v.id = es.vehicle_id
+        where es.site_id = $1 and c.code = $2 and es.session_end is null
+        order by es.id desc limit 1
+        """,
+        site_id,
+        charger_code,
+    )
+
+
+async def build_ev_plan_summary(
+    site_id: int, charger_code: str, conn: asyncpg.Connection
+) -> str | None:
+    """Markdown souhrn: stav baterie auta → cíl, deadline, nabíjecí okna z plánu."""
+    row = await get_open_session(site_id, charger_code, conn)
+    if row is None:
+        return None
+    ev_col = "ev1_setpoint_w" if charger_code.endswith("1") else "ev2_setpoint_w"
+    slots = await conn.fetch(
+        f"""
+        select pi.interval_start, pi.{ev_col} as w, pi.effective_buy_price
+        from ems.planning_interval pi
+        join ems.planning_run pr on pr.id = pi.run_id
+        where pr.site_id = $1 and pr.status = 'active'
+          and coalesce(pi.{ev_col}, 0) > 0
+        order by pi.interval_start
+        """,
+        site_id,
+    )
+
+    def _fmt(dt) -> str:
+        return dt.astimezone(_PRAGUE).strftime("%H:%M")
+
+    windows: list[str] = []
+    kwh = 0.0
+    prices: list[float] = []
+    if slots:
+        start = prev = slots[0]["interval_start"]
+        for r in slots:
+            ts = r["interval_start"]
+            if (ts - prev).total_seconds() > 900:
+                windows.append(f"{_fmt(start)}–{_fmt(prev)} (+15m)")
+                start = ts
+            prev = ts
+            kwh += float(r["w"]) * 0.25 / 1000.0
+            prices.append(float(r["effective_buy_price"] or 0))
+        windows.append(f"{_fmt(start)}–{_fmt(prev)} (+15m)")
+
+    soc = row["soc_at_connect_pct"]
+    tgt = row["target_soc_pct"]
+    cap = float(row["battery_capacity_kwh"] or 0)
+    need = max(0.0, (float(tgt or 0) - float(soc or 0)) / 100.0 * cap)
+    lines = [
+        f"🔌 **{row['vehicle_name'] or charger_code} připojeno**",
+        f"Baterie auta: **{soc if soc is not None else '?'} %** → cíl {tgt if tgt is not None else '?'} %"
+        + (f" (~{need:.0f} kWh)" if need else ""),
+    ]
+    dl = row["target_deadline"]
+    if dl is not None:
+        lines.append(f"Deadline: {dl.astimezone(_PRAGUE).strftime('%a %d.%m. %H:%M')}")
+    if windows:
+        avg_p = sum(prices) / max(1, len(prices))
+        lines.append(
+            f"Plán nabíjení: {'; '.join(windows[:4])} — {kwh:.1f} kWh, ø {avg_p:.2f} Kč/kWh"
+        )
+    else:
+        lines.append("Plán nabíjení: zatím žádné sloty (čeká na levné okno / PV)")
+    return "\n".join(lines)
+
+
+async def send_ev_arrival(site_id: int, charger_code: str, conn: asyncpg.Connection) -> None:
+    """Pošle souhrn po příjezdu: přednostně bot s tlačítky, jinak webhook."""
+    from services.notification_service import send_discord
+
+    text = await build_ev_plan_summary(site_id, charger_code, conn)
+    if text is None:
+        return
+    try:
+        from services.discord_bot import post_ev_arrival
+
+        row = await get_open_session(site_id, charger_code, conn)
+        if row is not None and await post_ev_arrival(
+            site_id, charger_code, int(row["session_id"]), text
+        ):
+            return
+    except Exception:
+        logger.exception("Discord bot post failed — fallback webhook")
+    await send_discord(conn, site_id, text, level="info")