fix(simulation): use hydraulic timestep

tests/api/test_simulation_endpoints.py

@@ -19,11 +19,18 @@ def _load_simulation_module(monkeypatch):
             timezone.utc
         )
 
+    def parse_clock_duration_seconds(value, field_name="duration"):
+        parts = [int(part) for part in value.split(":")]
+        hours, minutes = parts[0], parts[1]
+        seconds = parts[2] if len(parts) == 3 else 0
+        return hours * 3600 + minutes * 60 + seconds
+
     install_stub(
         monkeypatch,
         "app.services.time_api",
         {
             "parse_aware_time": parse_aware_time,
+            "parse_clock_duration_seconds": parse_clock_duration_seconds,
             "parse_utc_time": parse_utc_time,
         },
     )
@@ -31,6 +38,7 @@ def _load_simulation_module(monkeypatch):
         monkeypatch,
         "app.services.simulation",
         {
+            "get_time": lambda name: {"HYDRAULIC TIMESTEP": "0:15:00"},
             "run_simulation": lambda **kwargs: None,
             "query_corresponding_element_id_and_query_id": lambda name: None,
             "query_corresponding_pattern_id_and_query_id": lambda name: None,
@@ -227,6 +235,33 @@ def test_run_simulation_manually_by_date_uses_utc_aware_timestamps(monkeypatch):
     ]
 
 
+def test_run_simulation_manually_by_date_uses_hydraulic_timestep(monkeypatch):
+    module = _load_simulation_module(monkeypatch)
+    captured_calls = []
+
+    monkeypatch.setattr(
+        module.simulation,
+        "get_time",
+        lambda name: {"HYDRAULIC TIMESTEP": "1:00"},
+    )
+    monkeypatch.setattr(
+        module.simulation,
+        "run_simulation",
+        lambda **kwargs: captured_calls.append(kwargs),
+    )
+
+    module.run_simulation_manually_by_date(
+        "demo",
+        datetime(2025, 1, 1, 16, 0, 0, tzinfo=timezone.utc),
+        120,
+    )
+
+    assert [call["modify_pattern_start_time"] for call in captured_calls] == [
+        "2025-01-01T16:00:00+00:00",
+        "2025-01-01T17:00:00+00:00",
+    ]
+
+
 def test_runsimulationmanuallybydate_endpoint_accepts_timezone_aware_start_time(monkeypatch):
     module = _load_simulation_module(monkeypatch)
     captured = {}