Improve video carousel for smoother infinite scrolling

Refactors the `CategoryRow` component to implement a seamless infinite scrolling experience for the video carousel. This involves adjusting the `currentIndex` logic, duplicating video data for a continuous loop, and optimizing the transform calculation for mobile and desktop views.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 2eb1084e-b728-4449-9231-f1665924c8d5
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/8cc42625-c1f5-4e43-99bd-77f2c4dedee2/2eb1084e-b728-4449-9231-f1665924c8d5/QCN70f2

client/src/components/netflix-grid.tsx

@@ -141,14 +141,12 @@ function CategoryRow({ category, onVideoClick }: CategoryRowProps) {
   const videosToShow = 5; // Show 5 videos at a time
 
   const scroll = (direction: 'left' | 'right') => {
-    const totalVideos = category.videos.length;
-    
     if (direction === 'right') {
-      // Move one video forward (shift left to show next video)
-      setCurrentIndex(prev => (prev + 1) % totalVideos);
+      // Always move forward, let infinite loop handle the reset
+      setCurrentIndex(prev => prev + 1);
     } else {
-      // Move one video backward (shift right to show previous video)
-      setCurrentIndex(prev => prev === 0 ? totalVideos - 1 : prev - 1);
+      // Always move backward, let infinite loop handle the reset
+      setCurrentIndex(prev => prev - 1);
     }
   };
 
@@ -157,14 +155,22 @@ function CategoryRow({ category, onVideoClick }: CategoryRowProps) {
     scroll(direction);
   };
 
-  // Handle infinite scroll reset
+  // Initialize in middle section for true infinite scroll
+  useEffect(() => {
+    if (category.videos.length > 0) {
+      setCurrentIndex(category.videos.length); // Start in middle section
+    }
+  }, [category.videos.length]);
+
+  // Handle seamless infinite scroll
   useEffect(() => {
     const totalVideos = category.videos.length;
-    if (currentIndex >= totalVideos) {
-      // Reset to beginning for infinite loop
-      setTimeout(() => {
-        setCurrentIndex(0);
-      }, 500); // After animation completes
+    if (currentIndex >= totalVideos * 2) {
+      // Jump from end of 2nd section to start of 1st section
+      setCurrentIndex(totalVideos);
+    } else if (currentIndex < 0) {
+      // Jump from before 1st section to start of 2nd section  
+      setCurrentIndex(totalVideos - 1);
     }
   }, [currentIndex, category.videos.length]);
 
@@ -266,35 +272,39 @@ function CategoryRow({ category, onVideoClick }: CategoryRowProps) {
           <ChevronRight className="w-5 h-5 text-white" />
         </button>
 
-        {/* Carousel video row */}
-        <div 
-          className="flex space-x-2 md:space-x-3 pb-4 px-4 md:px-0 transition-transform duration-500 ease-in-out"
-          style={{
-            transform: `translateX(-${currentIndex * (224 + 12)}px)` // 224px video width + 12px spacing
-          }}
-        >
-          {[...category.videos, ...category.videos].map((video, index) => {
-            const actualIndex = index % category.videos.length;
-            return (
-              <div key={`${video.id}-${index}`} className="flex-shrink-0 w-28 md:w-52 relative group">
-                {/* Top 10 Number overlay for first category */}
-                {category.title.includes("Top 10") && (
-                  <div className="absolute top-1 left-1 z-20 text-white font-black text-3xl md:text-5xl drop-shadow-2xl"
-                       style={{ 
-                         textShadow: '4px 4px 8px rgba(0,0,0,0.8), -2px -2px 4px rgba(0,0,0,0.6)',
-                         WebkitTextStroke: '2px rgba(0,0,0,0.8)' 
-                       }}>
-                    {actualIndex + 1}
-                  </div>
-                )}
-                <VideoCard
-                  video={video}
-                  onClick={onVideoClick}
-                  className="w-full hover:scale-105 hover:z-10 transition-all duration-300 group-hover:shadow-xl rounded-md overflow-hidden"
-                />
-              </div>
-            );
-          })}
+        {/* Carousel video row - overflow hidden for seamless loop */}
+        <div className="overflow-hidden">
+          <div 
+            className="flex space-x-2 md:space-x-3 pb-4 px-4 md:px-0 transition-transform duration-500 ease-in-out"
+            style={{
+              transform: `translateX(-${currentIndex * (112 + 8)}px)`, // Mobile: 112px + 8px spacing
+              willChange: 'transform'
+            }}
+          >
+            {/* Triple the videos for seamless infinite scroll */}
+            {[...category.videos, ...category.videos, ...category.videos].map((video, index) => {
+              const actualIndex = index % category.videos.length;
+              return (
+                <div key={`${video.id}-${Math.floor(index / category.videos.length)}-${actualIndex}`} className="flex-shrink-0 w-28 md:w-52 relative group">
+                  {/* Top 10 Number overlay for first category */}
+                  {category.title.includes("Top 10") && (
+                    <div className="absolute top-1 left-1 z-20 text-white font-black text-3xl md:text-5xl drop-shadow-2xl"
+                         style={{ 
+                           textShadow: '4px 4px 8px rgba(0,0,0,0.8), -2px -2px 4px rgba(0,0,0,0.6)',
+                           WebkitTextStroke: '2px rgba(0,0,0,0.8)' 
+                         }}>
+                      {actualIndex + 1}
+                    </div>
+                  )}
+                  <VideoCard
+                    video={video}
+                    onClick={onVideoClick}
+                    className="w-full hover:scale-105 hover:z-10 transition-all duration-300 group-hover:shadow-xl rounded-md overflow-hidden"
+                  />
+                </div>
+              );
+            })}
+          </div>
         </div>
       </div>
     </div>