From 9e5940f0abbd428506aab475aa487336dc577f68 Mon Sep 17 00:00:00 2001
From: Paul Frazee <pfrazee@gmail.com>
Date: Fri, 9 Dec 2022 11:46:49 -0600
Subject: [PATCH] Improve aesthetic of main menu swipeout (use screen mask)

---
 src/view/com/util/gestures/HorzSwipe.tsx | 12 +++++++++-
 src/view/shell/mobile/index.tsx          | 28 ++++++++++++++++++++----
 2 files changed, 35 insertions(+), 5 deletions(-)

diff --git a/src/view/com/util/gestures/HorzSwipe.tsx b/src/view/com/util/gestures/HorzSwipe.tsx
index 0176bd4c..82b230bf 100644
--- a/src/view/com/util/gestures/HorzSwipe.tsx
+++ b/src/view/com/util/gestures/HorzSwipe.tsx
@@ -1,4 +1,4 @@
-import React from 'react'
+import React, {useState} from 'react'
 import {
   Animated,
   GestureResponderEvent,
@@ -19,6 +19,7 @@ interface Props {
   distThresholdDivisor?: number
   useNativeDriver?: boolean
   onSwipeStart?: () => void
+  onSwipeStartDirection?: (dx: number) => void
   onSwipeEnd?: (dx: number) => void
   children: React.ReactNode
 }
@@ -32,10 +33,12 @@ export function HorzSwipe({
   distThresholdDivisor = 1.75,
   useNativeDriver = false,
   onSwipeStart,
+  onSwipeStartDirection,
   onSwipeEnd,
   children,
 }: Props) {
   const winDim = useWindowDimensions()
+  const [dir, setDir] = useState<number>(0)
 
   const swipeVelocityThreshold = 35
   const swipeDistanceThreshold = winDim.width / distThresholdDivisor
@@ -66,6 +69,7 @@ export function HorzSwipe({
   }
 
   const startGesture = () => {
+    setDir(0)
     onSwipeStart?.()
 
     // TODO
@@ -94,6 +98,12 @@ export function HorzSwipe({
     }
 
     panX.setValue(clamp(diffX / swipeDistanceThreshold, -1, 1) * -1)
+
+    const newDir = diffX > 0 ? -1 : diffX < 0 ? 1 : 0
+    if (newDir !== dir) {
+      setDir(newDir)
+      onSwipeStartDirection?.(newDir)
+    }
   }
 
   const finishGesture = (
diff --git a/src/view/shell/mobile/index.tsx b/src/view/shell/mobile/index.tsx
index 04c4c469..1506b52e 100644
--- a/src/view/shell/mobile/index.tsx
+++ b/src/view/shell/mobile/index.tsx
@@ -113,6 +113,7 @@ export const MobileShell: React.FC = observer(() => {
   const [isTabsSelectorActive, setTabsSelectorActive] = useState(false)
   const scrollElRef = useRef<FlatList | undefined>()
   const winDim = useWindowDimensions()
+  const [menuSwipingDirection, setMenuSwipingDirection] = useState(0)
   const swipeGestureInterp = useAnimatedValue(0)
   const tabMenuInterp = useAnimatedValue(0)
   const newTabInterp = useAnimatedValue(0)
@@ -213,6 +214,15 @@ export const MobileShell: React.FC = observer(() => {
   const isMenuActive = store.shell.isMainMenuOpen
   const canSwipeLeft = store.nav.tab.canGoBack || !isMenuActive
   const canSwipeRight = isMenuActive
+  const onNavSwipeStartDirection = (dx: number) => {
+    if (dx < 0 && !store.nav.tab.canGoBack) {
+      setMenuSwipingDirection(dx)
+    } else if (dx > 0 && isMenuActive) {
+      setMenuSwipingDirection(dx)
+    } else {
+      setMenuSwipingDirection(0)
+    }
+  }
   const onNavSwipeEnd = (dx: number) => {
     if (dx < 0) {
       if (store.nav.tab.canGoBack) {
@@ -225,6 +235,7 @@ export const MobileShell: React.FC = observer(() => {
         store.shell.setMainMenuOpen(false)
       }
     }
+    setMenuSwipingDirection(0)
   }
   const swipeTranslateX = Animated.multiply(
     swipeGestureInterp,
@@ -256,6 +267,15 @@ export const MobileShell: React.FC = observer(() => {
       outputRange: [0, 0.6, 0],
     }),
   }
+  const menuSwipeOpacity =
+    menuSwipingDirection !== 0
+      ? {
+          opacity: swipeGestureInterp.interpolate({
+            inputRange: menuSwipingDirection > 0 ? [0, 1] : [-1, 0],
+            outputRange: [0.6, 0],
+          }),
+        }
+      : undefined
   // TODO
   // const tabMenuTransform = {
   //   transform: [{translateY: Animated.multiply(tabMenuInterp, -320)}],
@@ -301,6 +321,7 @@ export const MobileShell: React.FC = observer(() => {
           swipeEnabled
           canSwipeLeft={canSwipeLeft}
           canSwipeRight={canSwipeRight}
+          onSwipeStartDirection={onNavSwipeStartDirection}
           onSwipeEnd={onNavSwipeEnd}>
           <ScreenContainer style={styles.screenContainer}>
             {screenRenderDesc.screens.map(
@@ -348,6 +369,9 @@ export const MobileShell: React.FC = observer(() => {
               },
             )}
           </ScreenContainer>
+          {menuSwipingDirection !== 0 ? (
+            <Animated.View style={[styles.screenMask, menuSwipeOpacity]} />
+          ) : undefined}
           <Animated.View style={[styles.menuDrawer, menuSwipeTransform]}>
             <Menu
               visible={isMenuActive}
@@ -484,10 +508,6 @@ const styles = StyleSheet.create({
     bottom: 0,
     left: 0,
     right: 0,
-    borderTopWidth: 1,
-    borderTopColor: colors.gray2,
-    borderRightWidth: 1,
-    borderRightColor: colors.gray2,
   },
   topBarProtector: {
     position: 'absolute',