From 5f4a7fa9b131431640d4f9cf5aaff727a01fd429 Mon Sep 17 00:00:00 2001
From: "Janus C. H. Knudsen" <janus007@gmail.com>
Date: Mon, 13 Oct 2025 23:57:12 +0200
Subject: [PATCH] Improves edge scrolling boundary detection.

Enhances edge scrolling logic to prevent over-scrolling
by checking boundaries based on dragged element position.
This prevents scrolling past the top or bottom edges
of the time grid during drag operations.
Also adds debugging logs for scroll check.
---
 src/managers/EdgeScrollManager.ts | 60 +++++++++++++++++++++++++++----
 1 file changed, 53 insertions(+), 7 deletions(-)

diff --git a/src/managers/EdgeScrollManager.ts b/src/managers/EdgeScrollManager.ts
index ae71de0..7a30382 100644
--- a/src/managers/EdgeScrollManager.ts
+++ b/src/managers/EdgeScrollManager.ts
@@ -8,6 +8,8 @@ import { DragMoveEventPayload, DragStartEventPayload } from '../types/EventTypes
 
 export class EdgeScrollManager {
   private scrollableContent: HTMLElement | null = null;
+  private timeGrid: HTMLElement | null = null;
+  private draggedClone: HTMLElement | null = null;
   private scrollRAF: number | null = null;
   private mouseY = 0;
   private isDragging = false;
@@ -31,6 +33,8 @@ export class EdgeScrollManager {
     // Wait for DOM to be ready
     setTimeout(() => {
       this.scrollableContent = document.querySelector('swp-scrollable-content');
+      this.timeGrid = document.querySelector('swp-time-grid');
+      
       if (this.scrollableContent) {
         // Disable smooth scroll for instant auto-scroll
         this.scrollableContent.style.scrollBehavior = 'auto';
@@ -54,7 +58,9 @@ export class EdgeScrollManager {
   private subscribeToEvents(): void {
 
     // Listen to drag events from DragDropManager
-    this.eventBus.on('drag:start', () => {
+    this.eventBus.on('drag:start', (event: Event) => {
+      const payload = (event as CustomEvent).detail;
+      this.draggedClone = payload.draggedClone;
       this.startDrag();
     });
 
@@ -158,12 +164,52 @@ export class EdgeScrollManager {
       }
     }
 
-    if (vy !== 0 && this.isDragging) {
-      // Time-based scrolling for frame-rate independence
-      // The scroll listener will detect actual scrolling and emit edgescroll:started
-      this.scrollableContent.scrollTop += vy * dt;
-      this.rect = null; // Invalidate cache for next frame
-      this.scrollRAF = requestAnimationFrame((ts) => this.scrollTick(ts));
+    if (vy !== 0 && this.isDragging && this.timeGrid && this.draggedClone) {
+      // Check if we can scroll in the requested direction
+      const currentScrollTop = this.scrollableContent.scrollTop;
+      const scrollableHeight = this.scrollableContent.clientHeight;
+      const timeGridHeight = this.timeGrid.clientHeight;
+      
+      // Get dragged element position and height
+      const cloneRect = this.draggedClone.getBoundingClientRect();
+      const cloneBottom = cloneRect.bottom;
+      const timeGridRect = this.timeGrid.getBoundingClientRect();
+      const timeGridBottom = timeGridRect.bottom;
+      
+      // Check boundaries
+      const atTop = currentScrollTop <= 0 && vy < 0;
+      const atBottom = (cloneBottom >= timeGridBottom) && vy > 0;
+      
+      console.log('📊 Scroll check:', {
+        currentScrollTop,
+        scrollableHeight,
+        timeGridHeight,
+        cloneBottom,
+        timeGridBottom,
+        atTop,
+        atBottom,
+        vy
+      });
+      
+      if (atTop || atBottom) {
+        // At boundary - stop scrolling
+        if (this.isScrolling) {
+          this.isScrolling = false;
+          this.initialScrollTop = this.scrollableContent.scrollTop;
+          console.log('🛑 EdgeScrollManager: Edge-scroll stopped (reached boundary)');
+          this.eventBus.emit('edgescroll:stopped', {});
+        }
+        
+        // Continue RAF loop to detect when mouse moves away from boundary
+        if (this.isDragging) {
+          this.scrollRAF = requestAnimationFrame((ts) => this.scrollTick(ts));
+        }
+      } else {
+        // Not at boundary - apply scroll
+        this.scrollableContent.scrollTop += vy * dt;
+        this.rect = null; // Invalidate cache for next frame
+        this.scrollRAF = requestAnimationFrame((ts) => this.scrollTick(ts));
+      }
     } else {
       // Mouse moved away from edge - stop scrolling
       if (this.isScrolling) {