add swipeable banner slider with autoplay

src/components/FigmaBanner.tsx

@@ -1,3 +1,11 @@
+import {
+  useCallback,
+  useEffect,
+  useRef,
+  useState,
+  type PointerEvent as ReactPointerEvent,
+} from "react";
+
 const FIGMA_ASSET_BASE = "/assets/ark-library/figma";
 
 export const officialRecommendationCoverFallbacks = [
@@ -8,30 +16,217 @@ export const officialRecommendationCoverFallbacks = [
   `${FIGMA_ASSET_BASE}/official-recommendation-5.png`,
 ] as const;
 
+type BannerSlide = {
+  id: string;
+  mobile: string;
+  desktop: string;
+  alt: string;
+};
+
+const BANNER_SLIDES: BannerSlide[] = [
+  {
+    id: "ark-banner-1",
+    mobile: `${FIGMA_ASSET_BASE}/banner-mobile-1.png`,
+    desktop: `${FIGMA_ASSET_BASE}/banner-desktop.png`,
+    alt: "",
+  },
+  {
+    id: "ark-banner-2",
+    mobile: `${FIGMA_ASSET_BASE}/banner-375.png`,
+    desktop: `${FIGMA_ASSET_BASE}/banner-wide.png`,
+    alt: "",
+  },
+];
+
+const AUTOPLAY_MS = 5000;
+const RESUME_AFTER_INTERACTION_MS = 8000;
+
 export function FigmaBanner() {
+  const slides = BANNER_SLIDES;
+  const scrollerRef = useRef<HTMLDivElement>(null);
+  const [activeIndex, setActiveIndex] = useState(0);
+  const [autoplayPaused, setAutoplayPaused] = useState(false);
+  const resumeTimerRef = useRef<number | null>(null);
+  const dragStateRef = useRef<{
+    pointerId: number;
+    startX: number;
+    startScrollLeft: number;
+    moved: boolean;
+  } | null>(null);
+  const hasMultiple = slides.length > 1;
+
+  const goTo = useCallback((index: number, behavior: ScrollBehavior) => {
+    const scroller = scrollerRef.current;
+    if (!scroller) return;
+    const target = scroller.children[index] as HTMLElement | undefined;
+    if (!target) return;
+    scroller.scrollTo({ left: target.offsetLeft, behavior });
+  }, []);
+
+  const pauseAutoplay = useCallback(() => {
+    setAutoplayPaused(true);
+    if (resumeTimerRef.current !== null) {
+      window.clearTimeout(resumeTimerRef.current);
+    }
+    resumeTimerRef.current = window.setTimeout(() => {
+      setAutoplayPaused(false);
+      resumeTimerRef.current = null;
+    }, RESUME_AFTER_INTERACTION_MS);
+  }, []);
+
+  useEffect(
+    () => () => {
+      if (resumeTimerRef.current !== null) {
+        window.clearTimeout(resumeTimerRef.current);
+      }
+    },
+    [],
+  );
+
+  useEffect(() => {
+    const scroller = scrollerRef.current;
+    if (!scroller) return;
+
+    const handleScroll = () => {
+      const width = scroller.clientWidth;
+      if (width === 0) return;
+      const next = Math.round(scroller.scrollLeft / width);
+      setActiveIndex((prev) => (prev === next ? prev : next));
+    };
+
+    handleScroll();
+    scroller.addEventListener("scroll", handleScroll, { passive: true });
+    return () => scroller.removeEventListener("scroll", handleScroll);
+  }, [slides.length]);
+
+  useEffect(() => {
+    if (!hasMultiple || autoplayPaused) return;
+    const timer = window.setInterval(() => {
+      setActiveIndex((prev) => {
+        const next = (prev + 1) % slides.length;
+        goTo(next, "smooth");
+        return next;
+      });
+    }, AUTOPLAY_MS);
+    return () => window.clearInterval(timer);
+  }, [hasMultiple, autoplayPaused, slides.length, goTo]);
+
+  const handlePointerDown = (event: ReactPointerEvent<HTMLDivElement>) => {
+    if (event.pointerType !== "mouse") return;
+    const scroller = scrollerRef.current;
+    if (!scroller) return;
+    dragStateRef.current = {
+      pointerId: event.pointerId,
+      startX: event.clientX,
+      startScrollLeft: scroller.scrollLeft,
+      moved: false,
+    };
+    scroller.setPointerCapture(event.pointerId);
+    pauseAutoplay();
+  };
+
+  const handlePointerMove = (event: ReactPointerEvent<HTMLDivElement>) => {
+    const drag = dragStateRef.current;
+    if (!drag || drag.pointerId !== event.pointerId) return;
+    const scroller = scrollerRef.current;
+    if (!scroller) return;
+    const dx = event.clientX - drag.startX;
+    if (!drag.moved && Math.abs(dx) > 4) {
+      drag.moved = true;
+      scroller.style.scrollSnapType = "none";
+    }
+    if (drag.moved) {
+      scroller.scrollLeft = drag.startScrollLeft - dx;
+    }
+  };
+
+  const endDrag = (event: ReactPointerEvent<HTMLDivElement>) => {
+    const drag = dragStateRef.current;
+    if (!drag || drag.pointerId !== event.pointerId) return;
+    const scroller = scrollerRef.current;
+    dragStateRef.current = null;
+    if (!scroller) return;
+    if (scroller.hasPointerCapture(event.pointerId)) {
+      scroller.releasePointerCapture(event.pointerId);
+    }
+    if (drag.moved) {
+      const width = scroller.clientWidth || 1;
+      const nearest = Math.round(scroller.scrollLeft / width);
+      const clamped = Math.max(0, Math.min(slides.length - 1, nearest));
+      scroller.style.scrollSnapType = "";
+      goTo(clamped, "smooth");
+    }
+  };
+
   return (
-    <picture className="-mx-4 block overflow-hidden border border-[#2a2a32] bg-black shadow-[0_24px_70px_rgba(0,0,0,0.18)] min-[440px]:-mx-5 sm:-mx-6 md:mx-0 md:rounded-xl">
-      <source
-        media="(max-width: 439px)"
-        srcSet={`${FIGMA_ASSET_BASE}/banner-375.png`}
-      />
-      <source
-        media="(max-width: 575px)"
-        srcSet={`${FIGMA_ASSET_BASE}/banner-440.png`}
-      />
-      <source
-        media="(max-width: 767px)"
-        srcSet={`${FIGMA_ASSET_BASE}/banner-576.png`}
-      />
-      <img
-        src={`${FIGMA_ASSET_BASE}/banner-desktop.png`}
-        alt=""
-        className="h-auto w-full object-cover"
-        width={1280}
-        height={290}
-        loading="eager"
-        decoding="async"
-      />
-    </picture>
+    <div>
+      <div
+        ref={scrollerRef}
+        onPointerDown={handlePointerDown}
+        onPointerMove={handlePointerMove}
+        onPointerUp={endDrag}
+        onPointerCancel={endDrag}
+        onTouchStart={pauseAutoplay}
+        className="flex cursor-grab snap-x snap-mandatory overflow-x-auto overflow-y-hidden scroll-smooth select-none touch-pan-x [-ms-overflow-style:none] [scrollbar-width:none] active:cursor-grabbing [&::-webkit-scrollbar]:hidden"
+        role="region"
+        aria-roledescription="carousel"
+        aria-label="ARK Library banner"
+      >
+        {slides.map((slide, index) => (
+          <div
+            key={slide.id}
+            className="relative w-full shrink-0 snap-start"
+            role="group"
+            aria-roledescription="slide"
+            aria-label={`${index + 1} / ${slides.length}`}
+          >
+            <picture className="block w-full overflow-hidden rounded-xl bg-black">
+              <source media="(max-width: 767px)" srcSet={slide.mobile} />
+              <img
+                src={slide.desktop}
+                alt={slide.alt}
+                className="pointer-events-none h-[200px] w-full object-cover md:h-auto"
+                width={1280}
+                height={290}
+                loading={index === 0 ? "eager" : "lazy"}
+                decoding="async"
+                draggable={false}
+              />
+            </picture>
+          </div>
+        ))}
+      </div>
+
+      {hasMultiple ? (
+        <div
+          className="mt-3 flex items-center justify-center gap-2"
+          role="tablist"
+          aria-label="Banner pagination"
+        >
+          {slides.map((slide, index) => {
+            const active = index === activeIndex;
+            return (
+              <button
+                key={slide.id}
+                type="button"
+                role="tab"
+                aria-selected={active}
+                aria-label={`Go to slide ${index + 1}`}
+                onClick={() => {
+                  pauseAutoplay();
+                  setActiveIndex(index);
+                  goTo(index, "smooth");
+                }}
+                className={`h-1.5 rounded-full transition-all ${
+                  active
+                    ? "w-6 bg-ark-gold"
+                    : "w-1.5 bg-white/30 hover:bg-white/50"
+                }`}
+              />
+            );
+          })}
+        </div>
+      ) : null}
+    </div>
   );
 }