fix repeatable migrations

db/routines/R__013_fn_ev_arrival_stats.sql

@@ -0,0 +1,65 @@
+CREATE OR REPLACE FUNCTION ems.fn_update_ev_arrival_stats(
+    p_site_id    INT,
+    p_charger_id INT,
+    p_vehicle_id INT,
+    p_arrived_at TIMESTAMPTZ
+)
+RETURNS VOID
+LANGUAGE sql
+AS $$
+  INSERT INTO ems.ev_arrival_stats
+      (site_id, charger_id, vehicle_id, day_of_week, arrival_hour, sample_count, last_updated)
+  VALUES (
+      p_site_id,
+      p_charger_id,
+      p_vehicle_id,
+      EXTRACT(DOW FROM p_arrived_at AT TIME ZONE 'Europe/Prague')::INT,
+      EXTRACT(HOUR FROM p_arrived_at AT TIME ZONE 'Europe/Prague')::INT,
+      1,
+      now()
+  )
+  ON CONFLICT (site_id, charger_id, day_of_week, arrival_hour) DO UPDATE SET
+      sample_count = ems.ev_arrival_stats.sample_count + 1,
+      last_updated = now();
+$$;
+
+COMMENT ON FUNCTION ems.fn_update_ev_arrival_stats(INT, INT, INT, TIMESTAMPTZ) IS
+'Přidá jeden příjezd do statistiky. Volat při otevření nové EV session
+(telemetry_collector: přechod status available → preparing/charging).';
+
+
+CREATE OR REPLACE FUNCTION ems.fn_ev_expected_arrival(
+    p_site_id    INT,
+    p_charger_id INT,
+    p_for_date   DATE DEFAULT (
+        (CURRENT_TIMESTAMP AT TIME ZONE 'Europe/Prague')::date + 1
+    )
+)
+RETURNS TABLE (
+    expected_hour  INT,
+    confidence_pct INT,
+    sample_count   INT
+)
+LANGUAGE sql
+STABLE
+AS $$
+  SELECT
+      s.arrival_hour,
+      ROUND(
+          s.sample_count::NUMERIC
+          / NULLIF(SUM(s.sample_count) OVER (PARTITION BY s.day_of_week), 0)
+          * 100
+      )::INT,
+      s.sample_count
+  FROM ems.ev_arrival_stats s
+  WHERE s.site_id = p_site_id
+    AND s.charger_id = p_charger_id
+    AND s.day_of_week = EXTRACT(DOW FROM p_for_date)::INT
+    AND s.sample_count >= 2
+  ORDER BY s.sample_count DESC
+  LIMIT 3;
+$$;
+
+COMMENT ON FUNCTION ems.fn_ev_expected_arrival(INT, INT, DATE) IS
+'Top 3 nejčastější hodiny příjezdu EV pro den v týdnu odpovídající kalendářnímu datu p_for_date.
+Backend předává „zítřek“ v časové zóně lokality. Použití: notifikace, později solver.';