Improve generator control and status displays

src/reactor_sim/commands.py

@@ -24,6 +24,7 @@ class ReactorCommand:
     primary_pumps: dict[int, bool] | None = None
     secondary_pumps: dict[int, bool] | None = None
     generator_units: dict[int, bool] | None = None
+    generator_auto: bool | None = None
     maintenance_components: tuple[str, ...] = tuple()
 
     @classmethod

src/reactor_sim/dashboard.py

@@ -56,6 +56,7 @@ class ReactorDashboard:
             DashboardKey("k", "Toggle secondary pump 2"),
             DashboardKey("b", "Toggle generator 1"),
             DashboardKey("v", "Toggle generator 2"),
+            DashboardKey("x", "Toggle generator auto"),
             DashboardKey("t", "Toggle turbine"),
             DashboardKey("1/2/3", "Toggle turbine units 1-3"),
             DashboardKey("y/u/i", "Maintain turbine 1/2/3"),
@@ -146,6 +147,8 @@ class ReactorDashboard:
                 self._toggle_generator_unit(0)
             elif ch in (ord("v"), ord("V")):
                 self._toggle_generator_unit(1)
+            elif ch in (ord("x"), ord("X")):
+                self._queue_command(ReactorCommand(generator_auto=not self.reactor.generator_auto))
             elif ch in (ord("t"), ord("T")):
                 self._queue_command(ReactorCommand(turbine_on=not self.reactor.turbine_active))
             elif ord("1") <= ch <= ord("9"):
@@ -259,6 +262,7 @@ class ReactorDashboard:
         self.reactor = Reactor.default()
         self.start_state = None
         self.pending_command = None
+        self._last_state = None
         self.reset_requested = False
         self.log_buffer.clear()
 
@@ -468,9 +472,15 @@ class ReactorDashboard:
     def _turbine_status_lines(self) -> list[str]:
         if not self.reactor.turbine_unit_active:
             return ["n/a"]
-        return [
+        lines: list[str] = []
-            f"{idx + 1}:{'ON' if active else 'OFF'}" for idx, active in enumerate(self.reactor.turbine_unit_active)
+        for idx, active in enumerate(self.reactor.turbine_unit_active):
-        ]
+            label = f"{idx + 1}:"
+            status = "ON" if active else "OFF"
+            if idx < len(getattr(self._last_state, "turbines", [])):
+                t_state = self._last_state.turbines[idx]
+                status = getattr(t_state, "status", status)
+            lines.append(f"{label}{status}")
+        return lines
 
     def _total_load_supplied(self, state: PlantState) -> float:
         return sum(t.load_supplied_mw for t in state.turbines)
@@ -551,7 +561,8 @@ class ReactorDashboard:
         if index >= len(pumps):
             return "n/a"
         state = pumps[index]
-        return f"{'ON ' if state.active else 'OFF'} {state.flow_rate:6.0f} kg/s"
+        status = getattr(state, "status", "ON" if state.active else "OFF")
+        return f"{status:<8} {state.flow_rate:6.0f} kg/s"
 
     def _current_demand(self) -> float:
         if self.reactor.consumer:

src/reactor_sim/generator.py

@@ -17,6 +17,7 @@ class GeneratorState:
     spool_remaining: float
     power_output_mw: float
     battery_charge: float
+    status: str = "OFF"
 
 
 @dataclass
@@ -32,6 +33,7 @@ class DieselGenerator:
             return
         state.starting = True
         state.spool_remaining = self.spool_time
+        state.status = "STARTING"
         LOGGER.info("Generator starting (spool %.0fs)", self.spool_time)
 
     def stop(self, state: GeneratorState) -> None:
@@ -41,6 +43,7 @@ class DieselGenerator:
         state.starting = False
         state.spool_remaining = 0.0
         state.power_output_mw = 0.0
+        state.status = "OFF"
         LOGGER.info("Generator stopped")
 
     def step(self, state: GeneratorState, load_demand_mw: float, dt: float) -> float:
@@ -51,12 +54,15 @@ class DieselGenerator:
             if state.spool_remaining <= 0.0:
                 state.starting = False
                 state.running = True
+                state.status = "RUN"
                 LOGGER.info("Generator online at %.1f MW", self.rated_output_mw)
         elif state.running:
             available = self.rated_output_mw
             state.power_output_mw = min(available, load_demand_mw)
+            state.status = "RUN" if state.power_output_mw > 0 else "IDLE"
         else:
             state.power_output_mw = 0.0
+            state.status = "OFF"
 
         if state.running:
             state.battery_charge = min(1.0, state.battery_charge + 0.02 * dt)

src/reactor_sim/reactor.py

@@ -44,6 +44,7 @@ class Reactor:
     turbine_unit_active: list[bool] = field(default_factory=lambda: [True, True, True])
     shutdown: bool = False
     meltdown: bool = False
+    generator_auto: bool = True
     poison_alerts: set[str] = field(default_factory=set)
     maintenance_active: set[str] = field(default_factory=set)
 
@@ -115,10 +116,18 @@ class Reactor:
             mass_flow_rate=0.0,
             steam_quality=0.0,
         )
-        primary_pumps = [PumpState(active=self.primary_pump_active, flow_rate=0.0, pressure=0.5) for _ in range(2)]
+        primary_pumps = [
-        secondary_pumps = [PumpState(active=self.secondary_pump_active, flow_rate=0.0, pressure=0.5) for _ in range(2)]
+            PumpState(active=self.primary_pump_active and self.primary_pump_units[idx], flow_rate=0.0, pressure=0.5)
+            for idx in range(2)
+        ]
+        secondary_pumps = [
+            PumpState(active=self.secondary_pump_active and self.secondary_pump_units[idx], flow_rate=0.0, pressure=0.5)
+            for idx in range(2)
+        ]
         generator_states = [
-            GeneratorState(running=False, starting=False, spool_remaining=0.0, power_output_mw=0.0, battery_charge=1.0)
+            GeneratorState(
+                running=False, starting=False, spool_remaining=0.0, power_output_mw=0.0, battery_charge=1.0, status="OFF"
+            )
             for _ in self.generators
         ]
         turbine_states = [
@@ -218,6 +227,14 @@ class Reactor:
                     pump_state.pressure, desired_pressure, dt, self.primary_pump.spool_time
                 )
                 pump_state.active = (unit_enabled and power_ratio > 0.05) or pump_state.flow_rate > 1.0
+                if unit_enabled and pump_state.flow_rate < max(1.0, desired_flow * 0.8):
+                    pump_state.status = "STARTING"
+                elif not unit_enabled and pump_state.flow_rate > 1.0:
+                    pump_state.status = "STOPPING"
+                elif pump_state.active:
+                    pump_state.status = "RUN"
+                else:
+                    pump_state.status = "OFF"
                 total_flow += pump_state.flow_rate
                 loop_pressure = max(loop_pressure, pump_state.pressure)
             state.primary_loop.mass_flow_rate = total_flow
@@ -239,6 +256,7 @@ class Reactor:
                 pump_state.pressure = self._ramp_value(
                     pump_state.pressure, state.primary_loop.pressure, dt, self.primary_pump.spool_time
                 )
+                pump_state.status = "STOPPING" if pump_state.flow_rate > 0 else "OFF"
         if self.secondary_pump_active:
             total_flow = 0.0
             target_pressure = 12.0 * 0.75 + 2.0
@@ -257,6 +275,14 @@ class Reactor:
                     pump_state.pressure, desired_pressure, dt, self.secondary_pump.spool_time
                 )
                 pump_state.active = unit_enabled or pump_state.flow_rate > 1.0
+                if unit_enabled and pump_state.flow_rate < max(1.0, desired_flow * 0.8):
+                    pump_state.status = "STARTING"
+                elif not unit_enabled and pump_state.flow_rate > 1.0:
+                    pump_state.status = "STOPPING"
+                elif pump_state.active:
+                    pump_state.status = "RUN"
+                else:
+                    pump_state.status = "OFF"
                 total_flow += pump_state.flow_rate
                 loop_pressure = max(loop_pressure, pump_state.pressure)
             state.secondary_loop.mass_flow_rate = total_flow
@@ -278,6 +304,7 @@ class Reactor:
                 pump_state.pressure = self._ramp_value(
                     pump_state.pressure, state.secondary_loop.pressure, dt, self.secondary_pump.spool_time
                 )
+                pump_state.status = "STOPPING" if pump_state.flow_rate > 0 else "OFF"
 
         self.thermal.step_core(state.core, state.primary_loop, total_power, dt)
         if not self.secondary_pump_active or state.secondary_loop.mass_flow_rate <= 1.0:
@@ -334,8 +361,13 @@ class Reactor:
             turbine_state = state.turbines[idx]
             if idx in active_indices:
                 turbine.step(state.secondary_loop, turbine_state, steam_power_mw=power_per_unit, dt=dt)
+                if turbine_state.electrical_output_mw < max(1.0, power_per_unit * 0.7):
+                    turbine_state.status = "STARTING"
+                else:
+                    turbine_state.status = "RUN"
             else:
                 self._spin_down_turbine(turbine_state, dt, turbine.spool_time)
+                turbine_state.status = "STOPPING" if turbine_state.electrical_output_mw > 0 else "OFF"
         self._dispatch_consumer_load(state, active_indices)
 
     def _reset_turbine_state(self, turbine_state: TurbineState) -> None:
@@ -343,6 +375,7 @@ class Reactor:
         turbine_state.electrical_output_mw = 0.0
         turbine_state.load_demand_mw = 0.0
         turbine_state.load_supplied_mw = 0.0
+        turbine_state.status = "OFF"
 
     @staticmethod
     def _ramp_value(current: float, target: float, dt: float, time_constant: float) -> float:
@@ -405,6 +438,8 @@ class Reactor:
             self.shutdown = True
             overrides["rod_fraction"] = self.control.scram()
             self._set_turbine_state(False)
+        if command.generator_auto is not None:
+            self.generator_auto = command.generator_auto
         if command.power_setpoint is not None:
             self.control.set_power_setpoint(command.power_setpoint)
         if command.rod_manual is not None:
@@ -512,17 +547,18 @@ class Reactor:
                     GeneratorState(running=False, starting=False, spool_remaining=0.0, power_output_mw=0.0, battery_charge=1.0)
                 )
         deficit = max(0.0, aux_demand - turbine_electric)
-        if deficit > 0.0:
+        if self.generator_auto:
-            for idx, gen_state in enumerate(state.generators):
+            if deficit > 0.0:
-                if not (gen_state.running or gen_state.starting):
+                for idx, gen_state in enumerate(state.generators):
-                    self.generators[idx].start(gen_state)
+                    if not (gen_state.running or gen_state.starting):
-                    deficit -= self.generators[idx].rated_output_mw
+                        self.generators[idx].start(gen_state)
-                    if deficit <= 0:
+                        deficit -= self.generators[idx].rated_output_mw
-                        break
+                        if deficit <= 0:
-        elif turbine_electric > aux_demand:
+                            break
-            for idx, gen_state in enumerate(state.generators):
+            elif turbine_electric > aux_demand:
-                if gen_state.running and not gen_state.starting:
+                for idx, gen_state in enumerate(state.generators):
-                    self.generators[idx].stop(gen_state)
+                    if gen_state.running and not gen_state.starting:
+                        self.generators[idx].stop(gen_state)
 
         total_power = 0.0
         remaining = max(0.0, aux_demand - turbine_electric)
@@ -640,6 +676,7 @@ class Reactor:
             "turbine_units": self.turbine_unit_active,
             "shutdown": self.shutdown,
             "meltdown": self.meltdown,
+            "generator_auto": self.generator_auto,
             "maintenance_active": list(self.maintenance_active),
             "generators": [
                 {
@@ -648,6 +685,7 @@ class Reactor:
                     "spool_remaining": g.spool_remaining,
                     "power_output_mw": g.power_output_mw,
                     "battery_charge": g.battery_charge,
+                    "status": g.status,
                 }
                 for g in state.generators
             ],
@@ -671,6 +709,7 @@ class Reactor:
         self.turbine_active = metadata.get("turbine_active", any(self.turbine_unit_active))
         self.shutdown = metadata.get("shutdown", self.shutdown)
         self.meltdown = metadata.get("meltdown", self.meltdown)
+        self.generator_auto = metadata.get("generator_auto", self.generator_auto)
         maint = metadata.get("maintenance_active")
         if maint is not None:
             self.maintenance_active = set(maint)
@@ -691,7 +730,12 @@ class Reactor:
         # Back-fill pump state lists for compatibility.
         if not plant.primary_pumps or len(plant.primary_pumps) < 2:
             plant.primary_pumps = [
-                PumpState(active=self.primary_pump_active, flow_rate=plant.primary_loop.mass_flow_rate / 2, pressure=plant.primary_loop.pressure)
+                PumpState(
+                    active=self.primary_pump_active,
+                    flow_rate=plant.primary_loop.mass_flow_rate / 2,
+                    pressure=plant.primary_loop.pressure,
+                    status="OFF",
+                )
                 for _ in range(2)
             ]
         if not plant.secondary_pumps or len(plant.secondary_pumps) < 2:
@@ -700,6 +744,7 @@ class Reactor:
                     active=self.secondary_pump_active,
                     flow_rate=plant.secondary_loop.mass_flow_rate / 2,
                     pressure=plant.secondary_loop.pressure,
+                    status="OFF",
                 )
                 for _ in range(2)
             ]
@@ -726,6 +771,7 @@ class Reactor:
                         spool_remaining=0.0,
                         power_output_mw=0.0,
                         battery_charge=1.0,
+                        status="OFF",
                     )
                 )
         for idx, gen_state in enumerate(plant.generators):
@@ -736,6 +782,7 @@ class Reactor:
                 gen_state.spool_remaining = cfg.get("spool_remaining", gen_state.spool_remaining)
                 gen_state.power_output_mw = cfg.get("power_output_mw", gen_state.power_output_mw)
                 gen_state.battery_charge = cfg.get("battery_charge", gen_state.battery_charge)
+                gen_state.status = cfg.get("status", gen_state.status)
         return plant
 
     def _handle_heat_sink_loss(self, state: PlantState) -> None:

src/reactor_sim/state.py

@@ -54,6 +54,7 @@ class TurbineState:
     condenser_temperature: float
     load_demand_mw: float = 0.0
     load_supplied_mw: float = 0.0
+    status: str = "OFF"
 
 
 @dataclass
@@ -61,6 +62,7 @@ class PumpState:
     active: bool
     flow_rate: float
     pressure: float
+    status: str = "OFF"
 
 
 @dataclass

tests/test_simulation.py

@@ -206,6 +206,30 @@ def test_generator_spools_and_powers_pumps():
     assert state.primary_loop.mass_flow_rate > 0.0
 
 
+def test_generator_manual_mode_allows_single_unit_and_stop():
+    reactor = Reactor.default()
+    state = reactor.initial_state()
+    reactor.shutdown = False
+    reactor.control.manual_control = True
+    reactor.control.rod_fraction = 0.95
+    reactor.generator_auto = False
+    reactor.primary_pump_units = [True, False]
+    reactor.secondary_pump_units = [False, False]
+
+    reactor.step(state, dt=1.0, command=ReactorCommand(generator_units={1: True}, primary_pumps={1: True}))
+    assert state.generators[0].starting or state.generators[0].running
+
+    for _ in range(15):
+        reactor.step(state, dt=1.0)
+
+    assert state.generators[0].running is True
+    reactor.step(state, dt=1.0, command=ReactorCommand(generator_units={1: False}))
+    for _ in range(5):
+        reactor.step(state, dt=1.0)
+    assert state.generators[0].running is False
+    assert state.generators[1].running is False
+
+
 def test_meltdown_triggers_shutdown():
     reactor = Reactor.default()
     state = reactor.initial_state()