refactor animations once again

src/app/_components/Animated/useReveal.ts

@@ -0,0 +1,102 @@
+'use client'
+
+import { useGSAP } from "@gsap/react"
+import { ScrollTrigger } from "gsap/all"
+import type { RefObject } from "react"
+import { GSAP_DEBUG, useGsapContext } from "~/app/_providers/GsapProvicer"
+
+export type UseRevealOptions = {
+  position: gsap.Position
+  /** Skip the orchestrated entrance and let ScrollTrigger drive from the start. */
+  scrollOnly?: boolean
+  /**
+   * Reveal once and keep it: after the element animates in (entrance or first
+   * scroll-in) it never reverses on leave. Default false = animate out at the
+   * top and back in on scroll-up.
+   */
+  once?: boolean
+  debugId?: string
+  /**
+   * Build the hidden -> shown animation for `el`. It must be a single,
+   * *independent* animation (not added to any timeline): `play()` reveals,
+   * `reverse()` hides. The hook pauses it, schedules its entrance through the
+   * shared timeline, and lets a ScrollTrigger drive the very same animation on
+   * scroll — so the two modes never fight over the element.
+   */
+  makeReveal: (el: HTMLElement) => gsap.core.Tween | gsap.core.Timeline
+}
+
+/**
+ * Shared reveal behavior for cards, text and pop-ups: an element in view at
+ * load plays an orchestrated timeline entrance, then hands the *same* tween to
+ * a ScrollTrigger that animates it out at the top and back in on scroll-up. An
+ * element off-screen at load is ScrollTrigger-driven from the start.
+ */
+export function useReveal(
+  ref: RefObject<HTMLElement | null>,
+  { position, scrollOnly = false, once = false, debugId, makeReveal }: UseRevealOptions,
+) {
+  const ctx = useGsapContext()
+  useGSAP(() => {
+    const el = ref.current
+    if (!el || !ctx) return
+
+    const scroller = ctx.getScroller()
+    const scrollerEl = scroller instanceof Element ? scroller : undefined
+
+    const rect = el.getBoundingClientRect()
+    let top = 0
+    let bottom = window.innerHeight
+    if (scrollerEl) {
+      const r = scrollerEl.getBoundingClientRect()
+      top = r.top
+      bottom = r.top + r.height
+    }
+    const isInView = rect.bottom > top && rect.top < bottom
+
+    const reveal = makeReveal(el)
+    // A reveal that animates height (pop-ups) shifts every trigger below it.
+    // Re-measure as it animates so positions track the real layout instead of
+    // only correcting at the very end. requestRefresh is throttled + deferred to
+    // the next frame, so this won't re-enter a ScrollTrigger callback.
+    reveal.eventCallback("onUpdate", () => ctx.requestRefresh())
+    reveal.pause()
+
+    const baseTrigger = {
+      trigger: el,
+      start: "top bottom",
+      end: "bottom top",
+      scroller: scrollerEl,
+      markers: GSAP_DEBUG,
+      id: GSAP_DEBUG ? debugId : undefined,
+    }
+    // Full behavior: in at the bottom, out at the top, and back on scroll-up.
+    const addReplayTrigger = () =>
+      ScrollTrigger.create({
+        ...baseTrigger,
+        onEnter: () => reveal.play(),
+        onEnterBack: () => reveal.play(),
+        onLeave: () => reveal.reverse(),
+        onLeaveBack: () => reveal.reverse(),
+      })
+
+    if (isInView && !scrollOnly) {
+      // The shared timeline only decides *when* the entrance starts; the reveal
+      // plays independently so the ScrollTrigger can take it over afterwards.
+      ctx.schedule(() => reveal.play(), position)
+      // `once` elements keep their revealed state — no scroll trigger at all.
+      if (!once) ctx.onReady(addReplayTrigger)
+    } else if (isInView) {
+      // scrollOnly + already on screen: no enter crossing will fire, so reveal
+      // now. Keep a trigger for scroll-out unless this is a `once` element.
+      reveal.play()
+      if (!once) addReplayTrigger()
+    } else if (once) {
+      // Off-screen: reveal when first reached, then self-destruct so it never
+      // reverses.
+      ScrollTrigger.create({ ...baseTrigger, once: true, onEnter: () => reveal.play() })
+    } else {
+      addReplayTrigger()
+    }
+  }, { dependencies: [] })
+}