[macOS] Add FlingGestureHandler (#3028)

## Description

This PR adds `FlingGestureHandler` on `macOS`. From now, all handlers, except`ForceTouchGestureHandler`, are available on this platform 🥳 

## Test plan

Tested on newly added example.

MacOSExample/src/App.tsx

@@ -16,6 +16,7 @@ import Tap from './basic/tap';
 import LongPressExample from './basic/longPress';
 import ManualExample from './basic/manual';
 import HoverExample from './basic/hover';
+import FlingExample from './basic/fling';
 
 interface Example {
   name: string;
@@ -37,6 +38,7 @@ const EXAMPLES: ExamplesSection[] = [
       { name: 'LongPress', component: LongPressExample },
       { name: 'Manual', component: ManualExample },
       { name: 'Hover', component: HoverExample },
+      { name: 'Fling', component: FlingExample },
     ],
   },
 ];

MacOSExample/src/basic/fling/index.tsx

@@ -0,0 +1,90 @@
+import { StyleSheet, View } from 'react-native';
+import {
+  Directions,
+  Gesture,
+  GestureDetector,
+} from 'react-native-gesture-handler';
+import Animated, {
+  interpolateColor,
+  useAnimatedStyle,
+  useSharedValue,
+  withTiming,
+} from 'react-native-reanimated';
+
+const AnimationDuration = 100;
+
+const Colors = {
+  Initial: '#0a2688',
+  Active: '#6fcef5',
+};
+
+export default function FlingExample() {
+  const isActive = useSharedValue(false);
+  const colorProgress = useSharedValue(0);
+  const color1 = useSharedValue(Colors.Initial);
+  const color2 = useSharedValue(Colors.Active);
+
+  const animatedStyles = useAnimatedStyle(() => {
+    const backgroundColor = interpolateColor(
+      colorProgress.value,
+      [0, 1],
+      [color1.value, color2.value]
+    );
+
+    return {
+      transform: [
+        {
+          scale: withTiming(isActive.value ? 1.2 : 1, {
+            duration: AnimationDuration,
+          }),
+        },
+      ],
+      backgroundColor,
+    };
+  });
+
+  const g = Gesture.Fling()
+    .direction(Directions.LEFT | Directions.UP)
+    .onBegin(() => {
+      console.log('onBegin');
+    })
+    .onStart(() => {
+      console.log('onStart');
+      isActive.value = true;
+      colorProgress.value = withTiming(1, {
+        duration: AnimationDuration,
+      });
+    })
+    .onEnd(() => console.log('onEnd'))
+    .onFinalize((_, success) => {
+      console.log('onFinalize', success);
+
+      isActive.value = false;
+
+      colorProgress.value = withTiming(0, {
+        duration: AnimationDuration,
+      });
+    });
+
+  return (
+    <View style={styles.container}>
+      <GestureDetector gesture={g}>
+        <Animated.View style={[styles.box, animatedStyles]} />
+      </GestureDetector>
+    </View>
+  );
+}
+
+const styles = StyleSheet.create({
+  container: {
+    flex: 1,
+    justifyContent: 'space-around',
+    alignItems: 'center',
+  },
+
+  box: {
+    width: 100,
+    height: 100,
+    borderRadius: 20,
+  },
+});

apple/Handlers/RNFlingHandler.h

@@ -1,3 +1,4 @@
+#import "../RNGHVector.h"
 #import "RNGestureHandler.h"
 
 @interface RNFlingGestureHandler : RNGestureHandler

apple/Handlers/RNFlingHandler.m

@@ -87,6 +87,154 @@ - (CGPoint)getLastLocation
 
 @end
 
+#else
+
+@interface RNBetterSwipeGestureRecognizer : NSGestureRecognizer {
+  dispatch_block_t failFlingAction;
+  int maxDuration;
+  int minVelocity;
+  double defaultAlignmentCone;
+  double axialDeviationCosine;
+  double diagonalDeviationCosine;
+}
+
+@property (atomic, assign) RNGestureHandlerDirection direction;
+@property (atomic, assign) int numberOfTouchesRequired;
+
+- (id)initWithGestureHandler:(RNGestureHandler *)gestureHandler;
+
+@end
+
+@implementation RNBetterSwipeGestureRecognizer {
+  __weak RNGestureHandler *_gestureHandler;
+
+  NSPoint startPosition;
+  double startTime;
+}
+
+- (id)initWithGestureHandler:(RNGestureHandler *)gestureHandler
+{
+  if ((self = [super initWithTarget:self action:@selector(handleGesture:)])) {
+    _gestureHandler = gestureHandler;
+
+    maxDuration = 1.0;
+    minVelocity = 700;
+
+    defaultAlignmentCone = 30;
+    axialDeviationCosine = [self coneToDeviation:defaultAlignmentCone];
+    diagonalDeviationCosine = [self coneToDeviation:(90 - defaultAlignmentCone)];
+  }
+  return self;
+}
+
+- (void)handleGesture:(NSPanGestureRecognizer *)gestureRecognizer
+{
+  [_gestureHandler handleGesture:self];
+}
+
+- (void)mouseDown:(NSEvent *)event
+{
+  [super mouseDown:event];
+
+  startPosition = [self locationInView:self.view];
+  startTime = CACurrentMediaTime();
+
+  self.state = NSGestureRecognizerStatePossible;
+
+  __weak typeof(self) weakSelf = self;
+
+  failFlingAction = dispatch_block_create(0, ^{
+    __strong typeof(self) strongSelf = weakSelf;
+
+    if (strongSelf) {
+      strongSelf.state = NSGestureRecognizerStateFailed;
+    }
+  });
+
+  dispatch_after(
+      dispatch_time(DISPATCH_TIME_NOW, (int64_t)(maxDuration * NSEC_PER_SEC)),
+      dispatch_get_main_queue(),
+      failFlingAction);
+}
+
+- (void)mouseDragged:(NSEvent *)event
+{
+  [super mouseDragged:event];
+
+  NSPoint currentPosition = [self locationInView:self.view];
+  double currentTime = CACurrentMediaTime();
+
+  NSPoint distance;
+  distance.x = currentPosition.x - startPosition.x;
+  distance.y = startPosition.y - currentPosition.y;
+
+  double timeDelta = currentTime - startTime;
+
+  Vector *velocityVector = [Vector fromVelocityX:(distance.x / timeDelta) withVelocityY:(distance.y / timeDelta)];
+
+  [self tryActivate:velocityVector];
+}
+
+- (void)mouseUp:(NSEvent *)event
+{
+  [super mouseUp:event];
+
+  dispatch_block_cancel(failFlingAction);
+
+  self.state =
+      self.state == NSGestureRecognizerStateChanged ? NSGestureRecognizerStateEnded : NSGestureRecognizerStateFailed;
+}
+
+- (void)tryActivate:(Vector *)velocityVector
+{
+  bool isAligned = NO;
+
+  for (int i = 0; i < directionsSize; ++i) {
+    if ([self getAlignment:axialDirections[i]
+            withMinimalAlignmentCosine:axialDeviationCosine
+                    withVelocityVector:velocityVector]) {
+      isAligned = YES;
+      break;
+    }
+  }
+
+  if (!isAligned) {
+    for (int i = 0; i < directionsSize; ++i) {
+      if ([self getAlignment:diagonalDirections[i]
+              withMinimalAlignmentCosine:diagonalDeviationCosine
+                      withVelocityVector:velocityVector]) {
+        isAligned = YES;
+        break;
+      }
+    }
+  }
+
+  bool isFastEnough = velocityVector.magnitude >= minVelocity;
+
+  if (isAligned && isFastEnough) {
+    self.state = NSGestureRecognizerStateChanged;
+  }
+}
+
+- (BOOL)getAlignment:(RNGestureHandlerDirection)direction
+    withMinimalAlignmentCosine:(double)minimalAlignmentCosine
+            withVelocityVector:(Vector *)velocityVector
+{
+  Vector *directionVector = [Vector fromDirection:direction];
+  return ((self.direction & direction) == direction) &&
+      [velocityVector isSimilar:directionVector withThreshold:minimalAlignmentCosine];
+}
+
+- (double)coneToDeviation:(double)degrees
+{
+  double radians = (degrees * M_PI) / 180;
+  return cos(radians / 2);
+}
+
+@end
+
+#endif
+
 @implementation RNFlingGestureHandler
 
 - (instancetype)initWithTag:(NSNumber *)tag
@@ -100,8 +248,8 @@ - (instancetype)initWithTag:(NSNumber *)tag
 - (void)resetConfig
 {
   [super resetConfig];
-  UISwipeGestureRecognizer *recognizer = (UISwipeGestureRecognizer *)_recognizer;
-  recognizer.direction = UISwipeGestureRecognizerDirectionRight;
+  RNBetterSwipeGestureRecognizer *recognizer = (RNBetterSwipeGestureRecognizer *)_recognizer;
+  recognizer.direction = RNGestureHandlerDirectionRight;
 #if !TARGET_OS_TV
   recognizer.numberOfTouchesRequired = 1;
 #endif
@@ -110,7 +258,7 @@ - (void)resetConfig
 - (void)configure:(NSDictionary *)config
 {
   [super configure:config];
-  UISwipeGestureRecognizer *recognizer = (UISwipeGestureRecognizer *)_recognizer;
+  RNBetterSwipeGestureRecognizer *recognizer = (RNBetterSwipeGestureRecognizer *)_recognizer;
 
   id prop = config[@"direction"];
   if (prop != nil) {
@@ -125,6 +273,7 @@ - (void)configure:(NSDictionary *)config
 #endif
 }
 
+#if !TARGET_OS_OSX
 - (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
 {
   RNGestureHandlerState savedState = _lastState;
@@ -154,21 +303,6 @@ - (RNGestureHandlerEventExtraData *)eventExtraData:(id)_recognizer
        withNumberOfTouches:recognizer.numberOfTouches
            withPointerType:_pointerType];
 }
-@end
-
-#else
-
-@implementation RNFlingGestureHandler
-
-- (instancetype)initWithTag:(NSNumber *)tag
-{
-  RCTLogWarn(@"FlingGestureHandler is not supported on macOS");
-  if ((self = [super initWithTag:tag])) {
-    _recognizer = [NSGestureRecognizer alloc];
-  }
-  return self;
-}
+#endif
 
 @end
-
-#endif

apple/RNGHVector.h

@@ -0,0 +1,31 @@
+//
+//  RNGHVector.h
+//  Pods
+//
+//  Created by Michał Bert on 05/08/2024.
+//
+
+#import "RNGestureHandlerDirection.h"
+
+#ifndef RNGHVector_h
+#define RNGHVector_h
+
+@interface Vector : NSObject
+
+@property (atomic, readonly, assign) double x;
+@property (atomic, readonly, assign) double y;
+@property (atomic, readonly, assign) double unitX;
+@property (atomic, readonly, assign) double unitY;
+@property (atomic, readonly, assign) double magnitude;
+
++ (Vector *_Nonnull)fromDirection:(RNGestureHandlerDirection)direction;
++ (Vector *_Nonnull)fromVelocityX:(double)vx withVelocityY:(double)vy;
+- (nonnull instancetype)initWithX:(double)x withY:(double)y;
+- (double)computeSimilarity:(Vector *_Nonnull)other;
+- (BOOL)isSimilar:(Vector *_Nonnull)other withThreshold:(double)threshold;
+
+@end
+
+static double MINIMAL_RECOGNIZABLE_MAGNITUDE = 0.1;
+
+#endif /* RNGHVector_h */