From fa88f76b3c29c8e2021da53f830ce07b5b586a5f Mon Sep 17 00:00:00 2001
From: Jinwoo-H <jinwoo0825@gmail.com>
Date: Sun, 19 Apr 2026 23:24:03 -0400
Subject: [PATCH] refactor: extract scheduleSplitScrollRestore to stay under
 max-lines lint

Moves the two-phase scroll restoration schedule (double-rAF + 200ms
timeout) into pane-split-scroll.ts so both pane-manager.ts and
pane-tree-ops.ts stay under the 300-line oxlint limit.
---
 .../src/lib/pane-manager/pane-manager.ts      | 42 ++++---------------
 .../src/lib/pane-manager/pane-split-scroll.ts | 37 ++++++++++++++++
 2 files changed, 44 insertions(+), 35 deletions(-)
 create mode 100644 src/renderer/src/lib/pane-manager/pane-split-scroll.ts

diff --git a/src/renderer/src/lib/pane-manager/pane-manager.ts b/src/renderer/src/lib/pane-manager/pane-manager.ts
index d6737f46..0765551a 100644
--- a/src/renderer/src/lib/pane-manager/pane-manager.ts
+++ b/src/renderer/src/lib/pane-manager/pane-manager.ts
@@ -33,9 +33,9 @@ import {
   safeFit,
   fitAllPanesInternal,
   captureScrollState,
-  restoreScrollState,
   refitPanesUnder
 } from './pane-tree-ops'
+import { scheduleSplitScrollRestore } from './pane-split-scroll'
 
 export type { PaneManagerOptions, PaneStyleOptions, ManagedPane, DropZone }
 
@@ -129,40 +129,12 @@ export class PaneManager {
     void this.options.onPaneCreated?.(this.toPublic(newPane))
     this.options.onLayoutChanged?.()
 
-    // Why: reparenting the container resets the viewport scroll position
-    // immediately (browser clears scrollTop on DOM move). The early
-    // double-rAF restore fires after the first fit settles (~2 frames /
-    // ~32ms) to minimise the visible flash. The lock stays in place so
-    // intermediate fits don't interfere. The later 200ms timeout is the
-    // authoritative final restore that also clears the lock — it catches
-    // any late async reflows (ResizeObserver 150ms debounce, WebGL
-    // context-loss rAFs) that might shift the position after the early
-    // restore.
-    const existingPaneId = existing.id
-
-    requestAnimationFrame(() => {
-      requestAnimationFrame(() => {
-        if (this.destroyed) {
-          return
-        }
-        const live = this.panes.get(existingPaneId)
-        if (live?.pendingSplitScrollState) {
-          restoreScrollState(live.terminal, scrollState)
-        }
-      })
-    })
-
-    setTimeout(() => {
-      if (this.destroyed) {
-        return
-      }
-      const live = this.panes.get(existingPaneId)
-      if (!live) {
-        return
-      }
-      live.pendingSplitScrollState = null
-      restoreScrollState(live.terminal, scrollState)
-    }, 200)
+    scheduleSplitScrollRestore(
+      (id) => this.panes.get(id),
+      existing.id,
+      scrollState,
+      () => this.destroyed
+    )
 
     return this.toPublic(newPane)
   }
diff --git a/src/renderer/src/lib/pane-manager/pane-split-scroll.ts b/src/renderer/src/lib/pane-manager/pane-split-scroll.ts
new file mode 100644
index 00000000..e405fb5c
--- /dev/null
+++ b/src/renderer/src/lib/pane-manager/pane-split-scroll.ts
@@ -0,0 +1,37 @@
+import type { ManagedPaneInternal, ScrollState } from './pane-manager-types'
+import { restoreScrollState } from './pane-tree-ops'
+
+// Why: reparenting a terminal container during split resets the viewport
+// scroll position (browser clears scrollTop on DOM move). This schedules a
+// two-phase restore: an early double-rAF (~32ms) to minimise the visible
+// flash, plus a 200ms authoritative restore that also clears the scroll lock.
+export function scheduleSplitScrollRestore(
+  getPaneById: (id: number) => ManagedPaneInternal | undefined,
+  paneId: number,
+  scrollState: ScrollState,
+  isDestroyed: () => boolean
+): void {
+  requestAnimationFrame(() => {
+    requestAnimationFrame(() => {
+      if (isDestroyed()) {
+        return
+      }
+      const live = getPaneById(paneId)
+      if (live?.pendingSplitScrollState) {
+        restoreScrollState(live.terminal, scrollState)
+      }
+    })
+  })
+
+  setTimeout(() => {
+    if (isDestroyed()) {
+      return
+    }
+    const live = getPaneById(paneId)
+    if (!live) {
+      return
+    }
+    live.pendingSplitScrollState = null
+    restoreScrollState(live.terminal, scrollState)
+  }, 200)
+}