user can select 'plant' from dropdown menu

src/App/App.tsx

@@ -1,4 +1,4 @@
-import { Dispatch, ReactElement, SetStateAction, useEffect, useRef, useState } from "react";
+import { createElement, Dispatch, ReactElement, SetStateAction, useEffect, useRef, useState } from "react";
 
 import { emptyStatechart, Statechart } from "../statecharts/abstract_syntax";
 import { handleInputEvent, initialize } from "../statecharts/interpreter";
@@ -18,8 +18,11 @@ import { TraceableError } from "../statecharts/parser";
 import { getKeyHandler } from "./shortcut_handler";
 import { BottomPanel } from "./BottomPanel";
 import { emptyState } from "@/statecharts/concrete_syntax";
-import { usePersistentState } from "@/util/persistent_state";
 import { PersistentDetails } from "./PersistentDetails";
+import { DigitalWatch, DigitalWatchPlant } from "@/Plant/DigitalWatch/DigitalWatch";
+import { DummyPlant } from "@/Plant/Dummy/Dummy";
+import { Plant } from "@/Plant/Plant";
+import { usePersistentState } from "@/util/persistent_state";
 
 type EditHistory = {
   current: VisualEditorState,
@@ -27,6 +30,11 @@ type EditHistory = {
   future: VisualEditorState[],
 }
 
+const plants: [string, Plant<any>][] = [
+  ["dummy", DummyPlant],
+  ["digital watch", DigitalWatchPlant],
+]
+
 export function App() {
   const [mode, setMode] = useState<InsertMode>("and");
   const [historyState, setHistoryState] = useState<EditHistory>({current: emptyState, history: [], future: []});
@@ -36,6 +44,9 @@ export function App() {
   const [rtIdx, setRTIdx] = useState<number|undefined>();
   const [time, setTime] = useState<TimeMode>({kind: "paused", simtime: 0});
   const [modal, setModal] = useState<ReactElement|null>(null);
+  const [plantName, setPlantName] = usePersistentState("plant", "dummy");
+
+  const plant = plants.find(([pn, p]) => pn === plantName)![1];
 
   const editorState = historyState.current;
   const setEditorState = (cb: (value: VisualEditorState) => VisualEditorState) => {
@@ -192,6 +203,19 @@ export function App() {
 
   const highlightTransitions = (rtIdx === undefined) ? [] : rt[rtIdx].firedTransitions;
 
+
+  const plantStates = [];
+  let ps = plant.initial(e => {
+    // ...
+  });
+  for (let i=0; i<rt.length; i++) {
+    const r = rt[i];
+    for (const o of r.outputEvents) {
+      ps = plant.reducer(o, ps);
+    }
+    plantStates.push(ps);
+  }
+
   return <>
 
   {/* Modal dialog */}
@@ -270,7 +294,8 @@ export function App() {
           <Box sx={{
             flexGrow:1,
             overflow:'auto',
-            minHeight: '75%', // <-- allows us to always scroll down the sidebar far enough such that the execution history is enough in view
+            minHeight: 400,
+            // minHeight: '75%', // <-- allows us to always scroll down the sidebar far enough such that the execution history is enough in view
             }}>
             <Box sx={{ height: '100%'}}>
               <div ref={refRightSideBar}>
@@ -278,6 +303,20 @@ export function App() {
               </div>
             </Box>
           </Box>
+          <Box sx={{flex: '0 0 content'}}>
+            <PersistentDetails localStorageKey="showPlant" initiallyOpen={true}>
+              <summary>plant</summary>
+              <select
+                value={plantName}
+                onChange={e => setPlantName(() => e.target.value)}>
+                {plants.map(([plantName, p]) =>
+                  <option>{plantName}</option>
+                )}
+              </select>
+              {rtIdx!==undefined && <plant.render {...plantStates[rtIdx]}/>}
+              {/* <DigitalWatch alarm={true} light={true}  h={12} m={30} s={33}/> */}
+            </PersistentDetails>
+          </Box>
         </Stack>
       </Box>
 

src/App/BottomPanel.tsx

@@ -5,7 +5,6 @@ import "./BottomPanel.css";
 
 import head from "../head.svg" ;
 import { PersistentDetails } from "./PersistentDetails";
-import { DigitalWatch } from "@/Plant/DigitalWatch/DigitalWatch";
 
 export function BottomPanel(props: {errors: TraceableError[]}) {
   const [greeting, setGreeting] = useState(<><b><img src={head} style={{transform: "scaleX(-1)"}}/>&emsp;"Welcome to StateBuddy, buddy!"</b><br/></>);
@@ -18,7 +17,6 @@ export function BottomPanel(props: {errors: TraceableError[]}) {
 
   return <div className="toolbar bottom">
     {greeting}
-    <DigitalWatch alarm={true} light={true}  h={12} m={30} s={33}/>
     {props.errors.length > 0 &&
       <div className="errorStatus">
         <PersistentDetails initiallyOpen={false} localStorageKey="errorsExpanded">

src/Plant/DigitalWatch/DigitalWatch.tsx

@@ -7,12 +7,15 @@ import digitalFont from "./digital-font.ttf";
 import { Plant } from "../Plant";
 import { RaisedEvent } from "@/statecharts/runtime_types";
 
-type DigitalWatchProps = {
+type DigitalWatchState = {
   light: boolean;
   h: number;
   m: number;
   s: number;
   alarm: boolean;
+}
+
+type DigitalWatchProps = DigitalWatchState & {
   callbacks: {
     onTopLeftPressed: () => void;
     onTopRightPressed: () => void;
@@ -26,7 +29,7 @@ type DigitalWatchProps = {
 }
 
 export function DigitalWatch({light, h, m, s, alarm, callbacks}: DigitalWatchProps) {
-  const refText = useRef(null);
+  console.log(light, h, m);
   const twoDigits = (n: number) => ("0"+n.toString()).slice(-2);
   const hhmmss = `${twoDigits(h)}:${twoDigits(m)}:${twoDigits(s)}`;
 
@@ -43,7 +46,7 @@ export function DigitalWatch({light, h, m, s, alarm, callbacks}: DigitalWatchPro
       : <image width="222" height="236" xlinkHref={imgWatch}/>
       }
 
-      <text ref={refText} x="111" y="126" dominant-baseline="middle" text-anchor="middle" fontFamily="digital-font" fontSize={28}>{hhmmss}</text>
+      <text x="111" y="126" dominant-baseline="middle" text-anchor="middle" fontFamily="digital-font" fontSize={28}>{hhmmss}</text>
     
       <rect x="0" y="59" width="16" height="16" fill="#fff" fill-opacity="0" 
         onMouseDown={() => callbacks.onTopLeftPressed()}
@@ -87,6 +90,23 @@ export const DigitalWatchPlant: Plant<DigitalWatchProps> = {
     { kind: "event", event: "bottomRightReleased" },
     { kind: "event", event: "bottomLeftReleased" },
   ],
+  initial: (raise: (event: RaisedEvent) => void) => ({
+    light: false,
+    alarm: false,
+    h: 12,
+    m: 0,
+    s: 0,
+    callbacks: {
+      onTopLeftPressed: () => raise({ name: "topLeftPressed" }),
+      onTopRightPressed: () => raise({ name: "topRightPressed" }),
+      onBottomRightPressed: () => raise({ name: "bottomRightPressed" }),
+      onBottomLeftPressed: () => raise({ name: "bottomLeftPressed" }),
+      onTopLeftReleased: () => raise({ name: "topLeftReleased" }),
+      onTopRightReleased: () => raise({ name: "topRightReleased" }),
+      onBottomRightReleased: () => raise({ name: "bottomRightReleased" }),
+      onBottomLeftReleased: () => raise({ name: "bottomLeftReleased" }),
+    },
+  }),
   reducer: (inputEvent: RaisedEvent, state: DigitalWatchProps) => {
     if (inputEvent.name === "setH") {
       return { ...state, h: inputEvent.param };
@@ -106,4 +126,4 @@ export const DigitalWatchPlant: Plant<DigitalWatchProps> = {
     return state; // unknown event - ignore it
   },
   render: DigitalWatch,
-}
+}

src/Plant/Dummy/Dummy.tsx

@@ -0,0 +1,10 @@
+import { RaisedEvent } from "@/statecharts/runtime_types";
+import { Plant } from "../Plant";
+
+export const DummyPlant: Plant<{}> = {
+  inputEvents: [],
+  outputEvents: [],
+  initial: () => ({}),
+  reducer: (_inputEvent: RaisedEvent, _state: {}) => ({}),
+  render: (_state: {}) => <></>,
+}

src/Plant/Plant.ts

@@ -6,6 +6,7 @@ export type Plant<StateType> = {
   inputEvents: EventTrigger[];
   outputEvents: EventTrigger[];
 
+  initial: (raise: (event: RaisedEvent) => void) => StateType;
   reducer: (inputEvent: RaisedEvent, state: StateType) => StateType;
   render: (state: StateType) => ReactElement;
 }