From 9ac99ffabb47d1cf58f29746c52ee1d0ea7c2502 Mon Sep 17 00:00:00 2001
From: Chris Triantafilis <christophertriantafilis@gmail.com>
Date: Mon, 28 Oct 2024 19:28:07 -0400
Subject: [PATCH] fix: update scrollToIndex center-alignment

---
 packages/virtual-core/src/index.ts | 28 ++++++++++++----------------
 1 file changed, 12 insertions(+), 16 deletions(-)

diff --git a/packages/virtual-core/src/index.ts b/packages/virtual-core/src/index.ts
index 2b3d4ff1..1c65c59b 100644
--- a/packages/virtual-core/src/index.ts
+++ b/packages/virtual-core/src/index.ts
@@ -840,21 +840,13 @@ export class Virtualizer<
     const scrollOffset = this.getScrollOffset()
 
     if (align === 'auto') {
-      if (toOffset <= scrollOffset) {
-        align = 'start'
-      } else if (toOffset >= scrollOffset + size) {
+      if (toOffset >= scrollOffset + size) {
         align = 'end'
-      } else {
-        align = 'start'
       }
     }
 
-    if (align === 'start') {
-      toOffset = toOffset
-    } else if (align === 'end') {
-      toOffset = toOffset - size
-    } else if (align === 'center') {
-      toOffset = toOffset - size / 2
+    if (align === 'end') {
+        toOffset -= size
     }
 
     const scrollSizeProp = this.options.horizontal
@@ -892,12 +884,16 @@ export class Virtualizer<
       }
     }
 
-    const toOffset =
-      align === 'end'
-        ? item.end + this.options.scrollPaddingEnd
-        : item.start - this.options.scrollPaddingStart
+    const centerOffset = item.start - this.options.scrollPaddingStart + (item.size - size) / 2
 
-    return [this.getOffsetForAlignment(toOffset, align), align] as const
+    switch (align) {
+      case 'center':
+        return [this.getOffsetForAlignment(centerOffset, align), align] as const
+      case 'end':
+        return [this.getOffsetForAlignment(item.end + this.options.scrollPaddingEnd, align), align] as const
+      default:
+        return [this.getOffsetForAlignment(item.start - this.options.scrollPaddingStart, align), align] as const
+    }
   }
 
   private isDynamicMode = () => this.elementsCache.size > 0