From 360146136b03304676a73198e0a2d8034b9d16d1 Mon Sep 17 00:00:00 2001
From: jalal246 <jimmy002020@gmail.com>
Date: Fri, 3 Nov 2023 14:33:49 +0200
Subject: [PATCH] wip

---
 .../src/Container/DFlexParentContainer.ts     |  8 +-
 .../src/Container/DFlexScrollContainer.ts     |  6 +-
 .../src/Mechanism/DFlexMechanismController.ts | 78 ++++++++++++-------
 3 files changed, 54 insertions(+), 38 deletions(-)

diff --git a/packages/dflex-core-instance/src/Container/DFlexParentContainer.ts b/packages/dflex-core-instance/src/Container/DFlexParentContainer.ts
index 9e9f14d32..d61bbd7cd 100644
--- a/packages/dflex-core-instance/src/Container/DFlexParentContainer.ts
+++ b/packages/dflex-core-instance/src/Container/DFlexParentContainer.ts
@@ -16,7 +16,7 @@ class DFlexParentContainer {
   private _boundariesByRow: BoxNum;
 
   /** Strict Rect for siblings containers. */
-  private _siblingBoundaries: BoxNum | null;
+  private _siblingBoundaries: BoxRect | null;
 
   private _rect: BoxRect;
 
@@ -102,7 +102,7 @@ class DFlexParentContainer {
     if (this._siblingBoundaries) {
       this._siblingBoundaries.assignBiggestBox(rect);
     } else {
-      this._siblingBoundaries = new BoxNum(
+      this._siblingBoundaries = new BoxRect(
         rect.top,
         rect.right,
         rect.bottom,
@@ -155,8 +155,8 @@ class DFlexParentContainer {
    *
    * @returns
    */
-  getBoundaries(): AbstractBox<number> {
-    return this._siblingBoundaries || this._rect.getBox();
+  getBoundaries(): BoxRect {
+    return this._siblingBoundaries || this._rect;
   }
 
   /**
diff --git a/packages/dflex-core-instance/src/Container/DFlexScrollContainer.ts b/packages/dflex-core-instance/src/Container/DFlexScrollContainer.ts
index 5c48f28e4..b115df7f2 100644
--- a/packages/dflex-core-instance/src/Container/DFlexScrollContainer.ts
+++ b/packages/dflex-core-instance/src/Container/DFlexScrollContainer.ts
@@ -219,10 +219,8 @@ class DFlexScrollContainer {
     this._initializeOrDestroyThreshold("inner", null);
     this._initializeOrDestroyThreshold("inner", INNER_THRESHOLD);
 
-    if (this.hasDynamicVisibility()) {
-      this._initializeOrDestroyThreshold("outer", null);
-      this._initializeOrDestroyThreshold("outer", OUTER_THRESHOLD);
-    }
+    this._initializeOrDestroyThreshold("outer", null);
+    this._initializeOrDestroyThreshold("outer", OUTER_THRESHOLD);
   }
 
   private _updateOverflow(): void {
diff --git a/packages/dflex-dnd/src/Mechanism/DFlexMechanismController.ts b/packages/dflex-dnd/src/Mechanism/DFlexMechanismController.ts
index b91ef64e1..ba90f5f20 100644
--- a/packages/dflex-dnd/src/Mechanism/DFlexMechanismController.ts
+++ b/packages/dflex-dnd/src/Mechanism/DFlexMechanismController.ts
@@ -868,48 +868,66 @@ class DFlexMechanismController extends DFlexScrollableElement {
   private _processScroll(x: number, y: number, SK: string): boolean {
     let isOutSiblingsContainer = false;
 
-    const { scroll } = this.draggable;
+    const {
+      scroll: { enable },
+    } = this.draggable;
 
-    if (scroll.enable) {
-      this.scrollFeed(x, y, SK);
+    // If scrolling is disable, do nothing.
+    if (!enable) {
+      return false;
+    }
 
-      if (this.hasActiveScrolling()) {
-        if (!this.hasBeenScrolling) {
-          scheduler(store, null, {
-            onUpdate: () => {
-              isOutSiblingsContainer = this.draggable.isOutThreshold(SK);
+    const { containers, scrolls } = store;
 
-              // When it's inside the container, then the siblings are not lifted
-              if (!(isOutSiblingsContainer || this.isParentLocked)) {
-                this._updateContainerLockState(true);
-                this._fillHeadUp();
-              }
-            },
-          });
+    const container = containers.get(SK)!;
+    const scroll = scrolls.get(SK)!;
 
-          this.hasBeenScrolling = true;
-        }
+    const viewportRect = container.getBoundaries();
 
-        return true;
-      }
+    const [isInvisible] = scroll.isElmOutViewport(viewportRect, true);
 
-      if (this.hasBeenScrolling) {
-        isOutSiblingsContainer = this.draggable.isOutThreshold(SK);
+    // If rect is entirely visible, do nothing.
+    if (!isInvisible) {
+      return false;
+    }
 
-        if (!isOutSiblingsContainer && this.isParentLocked) {
-          const [scrollOffsetX, scrollOffsetY] =
-            this._calculateScrollOffsets(SK);
+    this.scrollFeed(x, y, SK);
 
-          // Update the position before calling the detector.
-          this.draggable.positions.setPos(x, y, scrollOffsetX, scrollOffsetY);
+    if (this.hasActiveScrolling()) {
+      if (!this.hasBeenScrolling) {
+        scheduler(store, null, {
+          onUpdate: () => {
+            isOutSiblingsContainer = this.draggable.isOutThreshold(SK);
 
-          this._detectNearestElm();
-        }
+            // When it's inside the container, then the siblings are not lifted
+            if (!(isOutSiblingsContainer || this.isParentLocked)) {
+              this._updateContainerLockState(true);
+              this._fillHeadUp();
+            }
+          },
+        });
 
-        this.hasBeenScrolling = false;
+        this.hasBeenScrolling = true;
+      }
 
-        return true;
+      return true;
+    }
+
+    if (this.hasBeenScrolling) {
+      isOutSiblingsContainer = this.draggable.isOutThreshold(SK);
+
+      if (!isOutSiblingsContainer && this.isParentLocked) {
+        const [scrollOffsetX, scrollOffsetY] = this._calculateScrollOffsets(SK);
+
+        // Update the position before calling the detector.
+        this.draggable.positions.setPos(x, y, scrollOffsetX, scrollOffsetY);
+
+        this._detectNearestElm();
       }
+
+      this.hasBeenScrolling = false;
+
+      return true;
     }
 
     return false;