Fix pinch zoom on iOS (#1133)

package-lock.json

@@ -32,7 +32,7 @@
         "lodash.camelcase": "^4.3.0",
         "mime-types": "^2.1.28",
         "npm-run-all": "^4.1.5",
-        "pointer-tracker": "^2.4.0",
+        "pointer-tracker": "^2.5.2",
         "postcss": "^7.0.35",
         "postcss-modules": "^3.2.2",
         "postcss-nested": "^4.2.3",
@@ -48,6 +48,20 @@
         "which": "^2.0.2"
       }
     },
+    "../pointer-tracker": {
+      "version": "2.5.0",
+      "extraneous": true,
+      "license": "Apache-2.0",
+      "devDependencies": {
+        "husky": "^4.2.5",
+        "lint-staged": "^10.2.11",
+        "prettier": "^2.0.5",
+        "rollup": "^2.23.1",
+        "rollup-plugin-terser": "^7.0.0",
+        "rollup-plugin-typescript2": "^0.27.2",
+        "typescript": "^3.9.7"
+      }
+    },
     "node_modules/@babel/code-frame": {
       "version": "7.10.4",
       "resolved": "https://registry.npmjs.org/@babel/code-frame/-/code-frame-7.10.4.tgz",
@@ -3871,9 +3885,9 @@
       }
     },
     "node_modules/pointer-tracker": {
-      "version": "2.4.0",
-      "resolved": "https://registry.npmjs.org/pointer-tracker/-/pointer-tracker-2.4.0.tgz",
-      "integrity": "sha512-pWI2tpaM/XNtc9mUTv42Rmjf6mkHvE8LT5DDEq0G7baPNhxNM9E3CepubPplSoSLk9E5bwQrAMyDcPVmJyTW4g==",
+      "version": "2.5.2",
+      "resolved": "https://registry.npmjs.org/pointer-tracker/-/pointer-tracker-2.5.2.tgz",
+      "integrity": "sha512-0OZXqAwKo2W7L8ViSpCMDyPj/U40w8zPS/0tfrszz3rcfGTdtQlWDCwKbMRG2YGn7zLxv2kUAIjklAwBgyHHfA==",
       "dev": true
     },
     "node_modules/postcss": {
@@ -11946,9 +11960,9 @@
       }
     },
     "pointer-tracker": {
-      "version": "2.4.0",
-      "resolved": "https://registry.npmjs.org/pointer-tracker/-/pointer-tracker-2.4.0.tgz",
-      "integrity": "sha512-pWI2tpaM/XNtc9mUTv42Rmjf6mkHvE8LT5DDEq0G7baPNhxNM9E3CepubPplSoSLk9E5bwQrAMyDcPVmJyTW4g==",
+      "version": "2.5.2",
+      "resolved": "https://registry.npmjs.org/pointer-tracker/-/pointer-tracker-2.5.2.tgz",
+      "integrity": "sha512-0OZXqAwKo2W7L8ViSpCMDyPj/U40w8zPS/0tfrszz3rcfGTdtQlWDCwKbMRG2YGn7zLxv2kUAIjklAwBgyHHfA==",
       "dev": true
     },
     "postcss": {

package.json

@@ -32,7 +32,7 @@
     "lodash.camelcase": "^4.3.0",
     "mime-types": "^2.1.28",
     "npm-run-all": "^4.1.5",
-    "pointer-tracker": "^2.4.0",
+    "pointer-tracker": "^2.5.2",
     "postcss": "^7.0.35",
     "postcss-modules": "^3.2.2",
     "postcss-nested": "^4.2.3",

src/client/lazy-app/Compress/Output/custom-els/PinchZoom/index.ts

@@ -1,5 +1,6 @@
 import PointerTracker, { Pointer } from 'pointer-tracker';
 import 'add-css:./styles.css';
+import { isSafari } from 'client/lazy-app/util';
 
 interface Point {
   clientX: number;
@@ -105,14 +106,23 @@ export default class PinchZoom extends HTMLElement {
     const pointerTracker: PointerTracker = new PointerTracker(this, {
       start: (pointer, event) => {
         // We only want to track 2 pointers at most
-        if (pointerTracker.currentPointers.length === 2 || !this._positioningEl)
+        if (
+          pointerTracker.currentPointers.length === 2 ||
+          !this._positioningEl
+        ) {
           return false;
+        }
         event.preventDefault();
         return true;
       },
       move: (previousPointers) => {
         this._onPointerMove(previousPointers, pointerTracker.currentPointers);
       },
+      // Unfortunately Safari on iOS has a bug where pointer event capturing
+      // doesn't work in some cases, and we hit those cases due to our event
+      // retargeting in pinch-zoom.
+      // https://bugs.webkit.org/show_bug.cgi?id=220196
+      avoidPointerEvents: isSafari,
     });
 
     this.addEventListener('wheel', (event) => this._onWheel(event));

src/client/lazy-app/Compress/Output/index.tsx

@@ -5,7 +5,7 @@ import './custom-els/PinchZoom';
 import './custom-els/TwoUp';
 import * as style from './style.css';
 import 'add-css:./style.css';
-import { shallowEqual } from '../../util';
+import { isSafari, shallowEqual } from '../../util';
 import {
   ToggleBackgroundIcon,
   AddIcon,
@@ -19,7 +19,6 @@ import { cleanSet } from '../../util/clean-modify';
 import type { SourceImage } from '../../Compress';
 import { linkRef } from 'shared/prerendered-app/util';
 import { drawDataToCanvas } from 'client/lazy-app/util/canvas';
-
 interface Props {
   source?: SourceImage;
   preprocessorState?: PreprocessorState;
@@ -275,7 +274,11 @@ export default class Output extends Component<Props, State> {
             onTouchStartCapture={this.onRetargetableEvent}
             onTouchEndCapture={this.onRetargetableEvent}
             onTouchMoveCapture={this.onRetargetableEvent}
-            onPointerDownCapture={this.onRetargetableEvent}
+            onPointerDownCapture={
+              // We avoid pointer events in our PinchZoom due to a Safari bug.
+              // That means we also need to avoid them here too, else we end up preventing the fallback mouse events.
+              isSafari ? undefined : this.onRetargetableEvent
+            }
             onMouseDownCapture={this.onRetargetableEvent}
             onWheelCapture={this.onRetargetableEvent}
           >

src/client/lazy-app/util/index.ts

@@ -295,3 +295,7 @@ export async function abortable<T>(
     }),
   ]);
 }
+
+export const isSafari =
+  /Safari\//.test(navigator.userAgent) &&
+  !/Chrom(e|ium)\//.test(navigator.userAgent);