fix nabijeni z gridu u fixnich tarifu

backend/tests/test_planning_charge_slot_selection.py

@@ -27,6 +27,8 @@ def _select_charge_slots(
     slots: list[PlanningSlot],
     battery: SimpleNamespace,
     current_soc_wh: float,
+    *,
+    purchase_pricing_mode: str = "spot",
 ) -> set[int]:
     """Kopie logiky z ems.fn_load_planning_slots_full (charge mask)."""
     charge_buf = float(getattr(battery, "charge_slot_buffer", 0) or 0)
@@ -72,6 +74,10 @@ def _select_charge_slots(
         selected.add(t)
         cum += min(pv_surplus_w, max_p_w) * eta * INTERVAL_H
 
+    # B) Non-PV grid charge — jen spot nákup (u fixed je buy všude stejný → jen FVE)
+    if purchase_pricing_mode == "fixed":
+        return selected
+
     # B) Non-PV: AM budget (OTE-first)
     am_candidates = [
         (t, getattr(slots[t], "is_predicted_price", False), float(slots[t].buy_price))
@@ -112,6 +118,8 @@ def _select_discharge_export_slots(
     battery: SimpleNamespace,
     current_soc_wh: float,
     charge_slots: set[int] | None = None,
+    *,
+    purchase_pricing_mode: str = "spot",
 ) -> set[int]:
     """Kopie logiky z ems.fn_load_planning_slots_full (discharge-export mask)."""
     discharge_buf = float(getattr(battery, "discharge_slot_buffer", 0) or 0)
@@ -138,10 +146,14 @@ def _select_discharge_export_slots(
         default=min(float(s.buy_price) for s in slots),
     )
 
+    if purchase_pricing_mode == "fixed":
+        sell_min = degrad
+    else:
+        sell_min = ref_buy + degrad
     candidates = [
         (t, float(slots[t].sell_price))
         for t in range(len(slots))
-        if float(slots[t].sell_price) > ref_buy + degrad
+        if float(slots[t].sell_price) > sell_min
     ]
     candidates.sort(key=lambda x: (-x[1], -x[0]))
 
@@ -330,5 +342,39 @@ class SelectDischargeExportSlotsTests(unittest.TestCase):
         self.assertNotIn(1, discharge, "sell 0.5 < ref 0.4 + 0.15")
 
 
+class FixedPurchasePricingTests(unittest.TestCase):
+    """purchase_pricing_mode=fixed: žádné grid CHARGE, export dle sell."""
+
+    def test_fixed_skips_non_pv_grid_charge_slots(self) -> None:
+        slots = [
+            _slot(buy=6.35, sell=2.0, hour_utc=14, load=500),
+            _slot(buy=6.35, sell=3.5, hour_utc=18, load=500),
+        ]
+        battery = _battery(charge_buf=1.3, uc_wh=12_500.0)
+        out = _select_charge_slots(
+            slots,
+            battery,
+            current_soc_wh=0.4 * battery.usable_capacity_wh,
+            purchase_pricing_mode="fixed",
+        )
+        self.assertEqual(out, set(), "fixed buy must not enable non-PV grid charge")
+
+    def test_fixed_allows_discharge_on_high_sell(self) -> None:
+        slots = [
+            _slot(buy=6.35, sell=1.0, hour_utc=10),
+            _slot(buy=6.35, sell=3.8, hour_utc=18),
+            _slot(buy=6.35, sell=3.2, hour_utc=19),
+        ]
+        battery = _battery(uc_wh=12_500.0, discharge_buf=2.0, degrad=0.3)
+        discharge = _select_discharge_export_slots(
+            slots,
+            battery,
+            current_soc_wh=0.5 * battery.usable_capacity_wh,
+            purchase_pricing_mode="fixed",
+        )
+        self.assertIn(1, discharge)
+        self.assertIn(2, discharge)
+
+
 if __name__ == "__main__":
     unittest.main()