From 4cb1211f2ca85231a3001c0030cae2db818763da Mon Sep 17 00:00:00 2001
From: Gibson Murray <gibmurrays@gmail.com>
Date: Thu, 3 Oct 2024 14:46:56 -0400
Subject: [PATCH] add: useFlip hook

---
 src/index.js     | 40 +++++++++++++++++++++++++++++++++++++++-
 types/index.d.ts | 10 +++++++++-
 2 files changed, 48 insertions(+), 2 deletions(-)

diff --git a/src/index.js b/src/index.js
index ad9119f..7434281 100644
--- a/src/index.js
+++ b/src/index.js
@@ -8,8 +8,9 @@
  * @author: Jack Doyle, jack@greensock.com
 */
 /* eslint-disable */
-import { useEffect, useLayoutEffect, useRef } from "react";
+import { useEffect, useLayoutEffect, useRef, useState, useCallback } from "react";
 import gsap from "gsap";
+import Flip from "gsap/Flip";
 
 let useIsomorphicLayoutEffect = typeof window !== "undefined" ? useLayoutEffect : useEffect,
     isConfig = value => value && !Array.isArray(value) && typeof(value) === "object",
@@ -47,3 +48,40 @@ export const useGSAP = (callback, dependencies = emptyArray) => {
 };
 useGSAP.register = core => { _gsap = core; };
 useGSAP.headless = true; // doesn't require the window to be registered.
+
+export const useFlip = (
+    target,
+    options
+) => {
+    const [isFlipped, setIsFlipped] = useState(false)
+    const flipStateRef = useRef(null)
+    const scopeRef = useRef(null)
+
+    const { props, simple, revertOnUpdate, ...vars } = options
+
+    const captureState = useCallback(() => {
+        const mergedVars = { props, simple, targets: target }
+        flipStateRef.current = Flip.getState(target, mergedVars)
+    }, [target, props, simple])
+
+    const flip = useCallback(() => {
+        captureState()
+        setIsFlipped((prev) => !prev)
+    }, [captureState])
+
+    useGSAP(
+        () => {
+            if (flipStateRef.current) {
+                Flip.from(flipStateRef.current, vars)
+                flipStateRef.current = null
+            }
+        },
+        {
+            scope: scopeRef,
+            dependencies: [isFlipped],
+            revertOnUpdate: revertOnUpdate,
+        }
+    )
+
+    return { isFlipped, flip, scopeRef }
+}
diff --git a/types/index.d.ts b/types/index.d.ts
index 91b62b0..2d5e0fc 100644
--- a/types/index.d.ts
+++ b/types/index.d.ts
@@ -30,4 +30,12 @@ interface useGSAPConfig {
  * @param {Array | useGSAPConfig} [dependencies]
  * @returns {useGSAPReturn} Object with "context" and "contextSafe" properties
 */
-export function useGSAP(func?: ContextFunc | useGSAPConfig, dependencies?: unknown[] | useGSAPConfig): useGSAPReturn;
\ No newline at end of file
+export function useGSAP(func?: ContextFunc | useGSAPConfig, dependencies?: unknown[] | useGSAPConfig): useGSAPReturn;
+
+/**
+ * Flip animation hook for animating React components that encapsulates the GSAP Flip API.
+ * @param target - The target element to animate.
+ * @param options - The options for the flip animation.
+ * @returns {isFlipped: boolean, flip: () => void, scope: ReactRef} - An object containing the flip state, the flip function, and the scope of the animation.
+ */
+export function useFlip(target: gsap.DOMTarget, options: Flip.FlipStateVars & Flip.FromToVars & { revertOnUpdate?: boolean }): { isFlipped: boolean, flip: () => void, scope: ReactRef };
\ No newline at end of file