From 32b1bd6050c20afd6569d867b855c4dbd861a81d Mon Sep 17 00:00:00 2001
From: Doug Martin <dmartin@concord.org>
Date: Fri, 5 Apr 2024 03:35:24 -0400
Subject: [PATCH] feat: Add fast simulation mode switch [PT-187321091]

---
 src/components/app.scss          |  2 +-
 src/components/app.tsx           | 35 +++++++++++++++-----
 src/components/speed-toggle.scss | 56 ++++++++++++++++++++++++++++++++
 src/components/speed-toggle.tsx  | 35 ++++++++++++++++++++
 4 files changed, 119 insertions(+), 9 deletions(-)
 create mode 100644 src/components/speed-toggle.scss
 create mode 100644 src/components/speed-toggle.tsx

diff --git a/src/components/app.scss b/src/components/app.scss
index 700c7f8..74c3f7b 100644
--- a/src/components/app.scss
+++ b/src/components/app.scss
@@ -131,7 +131,7 @@
             border: solid 1px #177991;
             background-color: #fff;
           }
-          input {
+          input.bordered {
             padding: 2px;
             width: 55px;
             border-radius: 1.5px;
diff --git a/src/components/app.tsx b/src/components/app.tsx
index bb0489f..d4b38eb 100644
--- a/src/components/app.tsx
+++ b/src/components/app.tsx
@@ -13,13 +13,19 @@ import PlayIcon from "../assets/play.svg";
 import PauseIcon from "../assets/pause.svg";
 import DropdownUpArrowIcon from "../assets/dropdown-up-arrow-icon.svg";
 import DropdownDownArrowIcon from "../assets/dropdown-down-arrow-icon.svg";
+import { SpeedToggle } from "./speed-toggle";
 
 import "./app.scss";
 
 type GenerationMode = "ready" | "playing" | "paused" | "stepping";
 
 const AnyStartingState = "(any)";
-const AnimationDelay = 1000;
+
+const fastAnimationOverride = parseInt((new URLSearchParams(window.location.search)).get("fastSpeed") ?? "", 10);
+const normalAnimationOverride = parseInt((new URLSearchParams(window.location.search)).get("normalSpeed") ?? "", 10);
+
+const FastAnimationDelay = isNaN(fastAnimationOverride) ? 250 : fastAnimationOverride;
+const NormalAnimationDelay = isNaN(normalAnimationOverride) ? 1000 : normalAnimationOverride;
 
 type SequenceGroup = {
   startingState: string;
@@ -88,6 +94,8 @@ export const App = () => {
   });
   const { generate } = useGenerator();
   const innerOutputRef = useRef<HTMLDivElement | null>(null);
+  const [fastSimulation, setFastSimulation] = useState(false);
+  const fastSimulationRef = useRef(false);
 
   const animating = useMemo(() => {
     return generationMode !== "ready";
@@ -209,13 +217,22 @@ export const App = () => {
   }, [animateCurrentSequenceIndex, finishAnimating]);
 
   const startAnimationInterval = useCallback(() => {
+    // this allows the animation speed to change during the animation
+    const getNext = () => Date.now() + (fastSimulationRef.current ? FastAnimationDelay : NormalAnimationDelay) - 1;
+    let next = getNext();
+
     animationInterval.current = window.setInterval(() => {
+      if (Date.now() < next) {
+        return;
+      }
+      next = getNext();
+
       if (currentSequenceAnimating()) {
         animateNextSequenceIndex();
       } else {
         finishAnimating();
       }
-    }, AnimationDelay);
+    }, FastAnimationDelay);
   }, [animateNextSequenceIndex, finishAnimating]);
 
   const stopAnimationInterval = () => {
@@ -272,6 +289,11 @@ export const App = () => {
     startAnimationInterval();
   }, [generateNewSequence, animateCurrentSequenceIndex, startAnimationInterval]);
 
+  const handleSpeedToggle = useCallback((value: boolean) => {
+    setFastSimulation(value);
+    fastSimulationRef.current = value;
+  }, [setFastSimulation]);
+
   const uiForGenerate = () => {
     const disabled = graphEmpty;
     const playLabel = generationMode === "playing" ? "Pause" : (generationMode === "paused" ? "Resume" : "Play");
@@ -294,7 +316,7 @@ export const App = () => {
           <div className="flex-row">
             <div>
               <label>Max Length:</label>
-              <input type="number"
+              <input className="bordered" type="number"
                 value={lengthLimit}
                 onChange={handleChangeLengthLimit}
                 min={1}
@@ -304,7 +326,7 @@ export const App = () => {
 
             <div>
               <label>Delimiter:</label>
-              <input type="text"
+              <input className="bordered" type="text"
                 onChange={handleChangeDelimiter}
                 value={delimiter}
                 placeholder="(none)"
@@ -314,10 +336,7 @@ export const App = () => {
             </div>
           </div>
 
-          <div>
-            <label>Simulation Speed:</label>
-            <div>TBD</div>
-          </div>
+          <SpeedToggle fastSimulation={fastSimulation} onChange={handleSpeedToggle} />
 
         </div>
         <div className="buttons">
diff --git a/src/components/speed-toggle.scss b/src/components/speed-toggle.scss
new file mode 100644
index 0000000..78a69b4
--- /dev/null
+++ b/src/components/speed-toggle.scss
@@ -0,0 +1,56 @@
+.speedToggle {
+
+  &>div {
+    margin: 7px 0;
+    display: flex;
+    gap: 10px;
+    cursor: pointer;
+
+    &>div {
+      width: 40px;
+    }
+
+    .fast {
+      flex-grow: 1;
+    }
+  }
+
+  input.slider {
+    cursor: pointer;
+    -webkit-appearance: none;
+    -moz-appearance: none;
+    appearance: none;
+    position: relative;
+    font-size: inherit;
+    width: 40px;
+    height: 14px;
+    box-sizing: content-box;
+    border: 1px solid #177991;
+    border-radius: 16px;
+    vertical-align: text-bottom;
+    margin: auto;
+    color: inherit;
+    background-color: #177991;
+
+    &::before {
+      content: "";
+      position: absolute;
+      top: 50%;
+      left: -3px;
+      transform: translate(0, -50%);
+      box-sizing: border-box;
+      width: 24px;
+      height: 24px;
+      margin: 0 0.15em;
+      border: 1px solid black;
+      border-radius: 50%;
+      background: currentcolor;
+      color: white;
+      box-shadow: 0 1px 5px 0 rgba(0, 0, 0, 0.35);
+    }
+
+    &:checked::before {
+      left: 18px;
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/components/speed-toggle.tsx b/src/components/speed-toggle.tsx
new file mode 100644
index 0000000..4188a55
--- /dev/null
+++ b/src/components/speed-toggle.tsx
@@ -0,0 +1,35 @@
+import React from "react";
+
+import "./speed-toggle.scss";
+
+interface Props {
+  fastSimulation: boolean;
+  onChange: (newValue: boolean) => void;
+}
+
+export const SpeedToggle = ({fastSimulation, onChange}: Props) => {
+  const handleChange = (e: React.ChangeEvent<HTMLInputElement>) => {
+    onChange(e.target.checked);
+  };
+  const getStyle = (isBold: boolean): React.CSSProperties => ({fontWeight: isBold ? "bold" : "normal"});
+  const title = `Simulation Speed: ${fastSimulation ? "Fast" : "Normal"}`;
+
+  return (
+    <div className="speedToggle">
+      <label htmlFor="simulationSpeed">Simulation Speed:</label>
+      <div>
+        <div style={getStyle(!fastSimulation)} onClick={() => onChange(false)}>Normal</div>
+        <input
+          id="simulationSpeed"
+          className="slider"
+          type="checkbox"
+          role="switch"
+          title={title}
+          checked={fastSimulation}
+          onChange={handleChange}
+        />
+        <div style={getStyle(fastSimulation)} className="fast" onClick={() => onChange(true)}>Fast</div>
+      </div>
+    </div>
+  );
+};