Reflect swipe velocity in swipe animation

cardstackview/src/main/java/com/yuyakaido/android/cardstackview/Duration.java

@@ -0,0 +1,22 @@
+package com.yuyakaido.android.cardstackview;
+
+public enum Duration {
+    Fast(100),
+    Normal(200),
+    Slow(500);
+
+    public final int duration;
+
+    Duration(int duration) {
+        this.duration = duration;
+    }
+
+    public static Duration fromVelocity(int velocity) {
+        if (velocity < 1000) {
+            return Slow;
+        } else if (velocity < 5000) {
+            return Normal;
+        }
+        return Fast;
+    }
+}

cardstackview/src/main/java/com/yuyakaido/android/cardstackview/RewindAnimationSetting.java

@@ -38,7 +38,7 @@ public Interpolator getInterpolator() {
 
     public static class Builder {
         private Direction direction = Direction.Bottom;
-        private int duration = 200;
+        private int duration = Duration.Normal.duration;
         private Interpolator interpolator = new DecelerateInterpolator();
 
         public RewindAnimationSetting.Builder setDirection(Direction direction) {

cardstackview/src/main/java/com/yuyakaido/android/cardstackview/SwipeAnimationSetting.java

@@ -38,7 +38,7 @@ public Interpolator getInterpolator() {
 
     public static class Builder {
         private Direction direction = Direction.Right;
-        private int duration = 200;
+        private int duration = Duration.Normal.duration;
         private Interpolator interpolator = new AccelerateInterpolator();
 
         public Builder setDirection(Direction direction) {

cardstackview/src/main/java/com/yuyakaido/android/cardstackview/internal/CardStackSnapHelper.java

@@ -7,9 +7,14 @@
 import android.view.View;
 
 import com.yuyakaido.android.cardstackview.CardStackLayoutManager;
+import com.yuyakaido.android.cardstackview.Duration;
+import com.yuyakaido.android.cardstackview.SwipeAnimationSetting;
 
 public class CardStackSnapHelper extends SnapHelper {
 
+    private int velocityX = 0;
+    private int velocityY = 0;
+
     @Nullable
     @Override
     public int[] calculateDistanceToFinalSnap(
@@ -25,10 +30,22 @@ public int[] calculateDistanceToFinalSnap(
                     CardStackSetting setting = manager.getCardStackSetting();
                     float horizontal = Math.abs(x) / (float) targetView.getWidth();
                     float vertical = Math.abs(y) / (float) targetView.getHeight();
-                    if (setting.swipeThreshold < horizontal || setting.swipeThreshold < vertical) {
+                    Duration duration = Duration.fromVelocity(velocityY < velocityX ? velocityX : velocityY);
+                    if (duration == Duration.Fast || setting.swipeThreshold < horizontal || setting.swipeThreshold < vertical) {
                         CardStackState state = manager.getCardStackState();
                         if (setting.directions.contains(state.getDirection())) {
                             state.targetPosition = state.topPosition + 1;
+
+                            SwipeAnimationSetting swipeAnimationSetting = new SwipeAnimationSetting.Builder()
+                                    .setDirection(setting.swipeAnimationSetting.getDirection())
+                                    .setDuration(duration.duration)
+                                    .setInterpolator(setting.swipeAnimationSetting.getInterpolator())
+                                    .build();
+                            manager.setSwipeAnimationSetting(swipeAnimationSetting);
+
+                            this.velocityX = 0;
+                            this.velocityY = 0;
+
                             CardStackSmoothScroller scroller = new CardStackSmoothScroller(CardStackSmoothScroller.ScrollType.ManualSwipe, manager);
                             scroller.setTargetPosition(manager.getTopPosition());
                             manager.startSmoothScroll(scroller);
@@ -43,7 +60,6 @@ public int[] calculateDistanceToFinalSnap(
                         manager.startSmoothScroll(scroller);
                     }
                 }
-
             }
         }
         return new int[2];
@@ -73,6 +89,8 @@ public int findTargetSnapPosition(
             int velocityX,
             int velocityY
     ) {
+        this.velocityX = Math.abs(velocityX);
+        this.velocityY = Math.abs(velocityY);
         if (layoutManager instanceof CardStackLayoutManager) {
             CardStackLayoutManager manager = (CardStackLayoutManager) layoutManager;
             return manager.getTopPosition();