Jesus sucks

backend/frontend/node_modules/@restart/hooks/cjs/useThrottledEventHandler.js

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+"use strict";
+
+exports.__esModule = true;
+exports.default = useThrottledEventHandler;
+var _react = require("react");
+var _useMounted = _interopRequireDefault(require("./useMounted"));
+var _useEventCallback = _interopRequireDefault(require("./useEventCallback"));
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+const isSyntheticEvent = event => typeof event.persist === 'function';
+/**
+ * Creates a event handler function throttled by `requestAnimationFrame` that
+ * returns the **most recent** event. Useful for noisy events that update react state.
+ *
+ * ```tsx
+ * function Component() {
+ *   const [position, setPosition] = useState();
+ *   const handleMove = useThrottledEventHandler<React.PointerEvent>(
+ *     (event) => {
+ *       setPosition({
+ *         top: event.clientX,
+ *         left: event.clientY,
+ *       })
+ *     }
+ *   )
+ *
+ *   return (
+ *     <div onPointerMove={handleMove}>
+ *        <div style={position} />
+ *     </div>
+ *   );
+ * }
+ * ```
+ *
+ * @param handler An event handler function
+ * @typeParam TEvent The event object passed to the handler function
+ * @returns The event handler with a `clear` method attached for clearing any in-flight handler calls
+ *
+ */
+function useThrottledEventHandler(handler) {
+  const isMounted = (0, _useMounted.default)();
+  const eventHandler = (0, _useEventCallback.default)(handler);
+  const nextEventInfoRef = (0, _react.useRef)({
+    event: null,
+    handle: null
+  });
+  const clear = () => {
+    cancelAnimationFrame(nextEventInfoRef.current.handle);
+    nextEventInfoRef.current.handle = null;
+  };
+  const handlePointerMoveAnimation = () => {
+    const {
+      current: next
+    } = nextEventInfoRef;
+    if (next.handle && next.event) {
+      if (isMounted()) {
+        next.handle = null;
+        eventHandler(next.event);
+      }
+    }
+    next.event = null;
+  };
+  const throttledHandler = event => {
+    if (!isMounted()) return;
+    if (isSyntheticEvent(event)) {
+      event.persist();
+    }
+    // Special handling for a React.Konva event which reuses the
+    // event object as it bubbles, setting target
+    else if ('evt' in event) {
+      event = Object.assign({}, event);
+    }
+    nextEventInfoRef.current.event = event;
+    if (!nextEventInfoRef.current.handle) {
+      nextEventInfoRef.current.handle = requestAnimationFrame(handlePointerMoveAnimation);
+    }
+  };
+  throttledHandler.clear = clear;
+  return throttledHandler;
+}