From c33fb846abc513aa51ae64afcf875c6284bfc878 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Arno=C5=A1t=20Pleskot?= <arnostpleskot@gmail.com>
Date: Thu, 14 Sep 2023 23:15:57 +0200
Subject: [PATCH] chore: cleanup

---
 src/components/App.tsx         | 66 ++++++++++++++--------------------
 src/scene/scrollConstraints.ts | 52 ++++++++-------------------
 src/types.ts                   |  2 +-
 3 files changed, 42 insertions(+), 78 deletions(-)

diff --git a/src/components/App.tsx b/src/components/App.tsx
index fee2694895..fa5ff00bd8 100644
--- a/src/components/App.tsx
+++ b/src/components/App.tsx
@@ -2009,28 +2009,23 @@ class App extends React.Component<AppProps, AppState> {
       );
     }
 
-    if (
-      this.state.scrollConstraints &&
-      this.state.scrollConstraints.isAnimating
-    ) {
-      const { shouldAnimate, animateTo } = constrainScrollState(this.state);
+    if (this.state.scrollConstraints?.animateOnNextUpdate) {
+      const newState = constrainScrollState(this.state, false);
 
       scrollConstraintsAnimationTimeout = setTimeout(() => {
         this.cancelInProgresAnimation?.();
-        if (shouldAnimate && animateTo) {
-          const fromValues = {
-            scrollX: this.state.scrollX,
-            scrollY: this.state.scrollY,
-            zoom: this.state.zoom.value,
-          };
-          const toValues = {
-            scrollX: animateTo.scrollX,
-            scrollY: animateTo.scrollY,
-            zoom: animateTo.zoom.value,
-          };
+        const fromValues = {
+          scrollX: this.state.scrollX,
+          scrollY: this.state.scrollY,
+          zoom: this.state.zoom.value,
+        };
+        const toValues = {
+          scrollX: newState.scrollX,
+          scrollY: newState.scrollY,
+          zoom: newState.zoom.value,
+        };
 
-          this.animateToConstrainedArea(fromValues, toValues);
-        }
+        this.animateToConstrainedArea(fromValues, toValues);
       }, 200);
     }
   }
@@ -2701,22 +2696,10 @@ class App extends React.Component<AppProps, AppState> {
       ...(this.state.scrollConstraints && {
         // manually reset if setState in onCancel wasn't committed yet
         shouldCacheIgnoreZoom: false,
-        scrollConstraints: {
-          ...this.state.scrollConstraints,
-          isAnimating: false,
-        },
       }),
     };
 
-    const { state, shouldAnimate } = constrainScrollState(newState);
-
-    this.setState({
-      ...state,
-      scrollConstraints: {
-        ...state.scrollConstraints!,
-        isAnimating: shouldAnimate,
-      },
-    });
+    this.setState(constrainScrollState(newState));
   };
 
   private animateToConstrainedArea = (
@@ -2728,7 +2711,7 @@ class App extends React.Component<AppProps, AppState> {
         shouldCacheIgnoreZoom: false,
         scrollConstraints: {
           ...state.scrollConstraints!,
-          isAnimating: false,
+          animateOnNextUpdate: false,
         },
       }));
     };
@@ -2744,7 +2727,7 @@ class App extends React.Component<AppProps, AppState> {
             shouldCacheIgnoreZoom: true,
             scrollConstraints: {
               ...state.scrollConstraints!,
-              isAnimating: false,
+              animateOnNextUpdate: false,
             },
           };
         });
@@ -8266,10 +8249,13 @@ class App extends React.Component<AppProps, AppState> {
           viewModeEnabled: true,
         },
         () => {
-          const { animateTo } = constrainScrollState({
-            ...this.state,
-            scrollConstraints,
-          });
+          const newState = constrainScrollState(
+            {
+              ...this.state,
+              scrollConstraints,
+            },
+            false,
+          );
 
           this.animateToConstrainedArea(
             {
@@ -8278,9 +8264,9 @@ class App extends React.Component<AppProps, AppState> {
               zoom: this.state.zoom.value,
             },
             {
-              scrollX: animateTo!.scrollX,
-              scrollY: animateTo!.scrollY,
-              zoom: animateTo!.zoom.value,
+              scrollX: newState.scrollX,
+              scrollY: newState.scrollY,
+              zoom: newState.zoom.value,
             },
           );
         },
diff --git a/src/scene/scrollConstraints.ts b/src/scene/scrollConstraints.ts
index 402dc80c0a..a0497170d4 100644
--- a/src/scene/scrollConstraints.ts
+++ b/src/scene/scrollConstraints.ts
@@ -310,7 +310,7 @@ let memoizedValues: {
     "zoom" | "width" | "height" | "scrollConstraints"
   >;
   constraints: ReturnType<typeof calculateConstraints>;
-  constraintsWithoutOverscroll: ReturnType<typeof calculateConstraints>;
+  allowOverscroll: boolean;
 } | null = null;
 
 /**
@@ -321,30 +321,24 @@ let memoizedValues: {
  */
 export const constrainScrollState = (
   state: AppState,
-): {
-  state: AppState;
-  shouldAnimate: boolean;
-  animateTo: {
-    scrollX: AppState["scrollX"];
-    scrollY: AppState["scrollY"];
-    zoom: AppState["zoom"];
-  } | null;
-} => {
+  allowOverscroll = true,
+): AppState => {
   if (!state.scrollConstraints) {
-    return { state, shouldAnimate: false, animateTo: null };
+    return state;
   }
   const { scrollX, scrollY, width, height, scrollConstraints, zoom } = state;
 
   const canUseMemoizedValues =
-    memoizedValues?.previousState.scrollConstraints && // can't use memoized values if there were no scrollConstraints in memoizedValues
     memoizedValues && // there are memoized values
+    memoizedValues.previousState.scrollConstraints && // can't use memoized values if there were no scrollConstraints in memoizedValues
+    memoizedValues.allowOverscroll === allowOverscroll && // allowOverscroll is the same as in memoizedValues
+    // current scrollConstraints are the same as in memoizedValues
     isShallowEqual(
-      // current scrollConstraints are the same as in memoizedValues
       state.scrollConstraints,
       memoizedValues.previousState.scrollConstraints!,
     ) &&
+    // current zoom and window dimensions are equal to those in memoizedValues
     isShallowEqual(
-      // current zoom and window dimensions are equal to those in memoizedValues
       { zoom: zoom.value, width, height },
       {
         zoom: memoizedValues.previousState.zoom.value,
@@ -360,17 +354,7 @@ export const constrainScrollState = (
         width,
         height,
         zoom,
-        allowOverscroll: true,
-      });
-
-  const constraintsWithoutOverscroll = canUseMemoizedValues
-    ? memoizedValues!.constraintsWithoutOverscroll
-    : calculateConstraints({
-        scrollConstraints,
-        width,
-        height,
-        zoom,
-        allowOverscroll: false,
+        allowOverscroll,
       });
 
   const constrainedValues = constrainScrollValues({
@@ -379,12 +363,6 @@ export const constrainScrollState = (
     scrollY,
   });
 
-  const animateTo = constrainScrollValues({
-    ...constraintsWithoutOverscroll,
-    scrollX,
-    scrollY,
-  });
-
   if (!canUseMemoizedValues) {
     memoizedValues = {
       previousState: {
@@ -394,16 +372,16 @@ export const constrainScrollState = (
         scrollConstraints: state.scrollConstraints,
       },
       constraints,
-      constraintsWithoutOverscroll,
+      allowOverscroll,
     };
   }
 
   return {
-    state: {
-      ...state,
-      ...constrainedValues,
+    ...state,
+    scrollConstraints: {
+      ...state.scrollConstraints,
+      animateOnNextUpdate: isViewportOutsideOfConstrainedArea(state),
     },
-    shouldAnimate: isViewportOutsideOfConstrainedArea(state),
-    animateTo,
+    ...constrainedValues,
   };
 };
diff --git a/src/types.ts b/src/types.ts
index 1859e17e33..e269e37bdf 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -661,7 +661,7 @@ export type ScrollConstraints = {
   y: number;
   width: number;
   height: number;
-  isAnimating?: boolean;
+  animateOnNextUpdate?: boolean;
   viewportZoomFactor?: number;
   lockZoom?: boolean;
 };