From cdfe8f1a39c64672b1eb6becdc7d644ce1fb09ac Mon Sep 17 00:00:00 2001
From: DiTus <ditus@o2.pl>
Date: Sat, 21 Mar 2026 21:57:28 +0100
Subject: [PATCH] fix: improve timeframe-independent dragging and prevent
 undefined dragStartPos error

---
 js/ui/drawing-tools.js | 57 +++++++++++++++++++++++++++++-------------
 1 file changed, 40 insertions(+), 17 deletions(-)

diff --git a/js/ui/drawing-tools.js b/js/ui/drawing-tools.js
index db4baa3..d6eb959 100644
--- a/js/ui/drawing-tools.js
+++ b/js/ui/drawing-tools.js
@@ -312,10 +312,17 @@ export class DrawingManager {
             if (pos.time === null || pos.price === null) return;
             const d = this.selectedDrawing;
             
+            // Safety check for dragStartPos
+            if (!this.dragStartPos) {
+                this.dragStartPos = pos;
+                return;
+            }
+            
             if (this.dragMode === 'label') {
                 // Free movement of ONLY the label field
                 const dx = pos.x - this.dragStartPos.x;
                 const dy = pos.y - this.dragStartPos.y;
+                if (!d.labelOffset) d.labelOffset = { x: 0, y: 0 };
                 d.labelOffset.x += dx;
                 d.labelOffset.y += dy;
                 this.dragStartPos = pos; 
@@ -328,20 +335,34 @@ export class DrawingManager {
             } else if (this.dragMode === 'p2') {
                 d.p2 = { time: pos.time, price: pos.price };
             } else if (this.dragMode === 'all') {
-                const timeDiff = pos.time - this.dragStartPos.time;
+                let timeDiff = pos.time - this.dragStartPos.time;
                 const priceDiff = pos.price - this.dragStartPos.price;
-                if (d.p1 && d.p2) {
-                    d.p1.time = this.startP1.time + timeDiff;
-                    d.p1.price = this.startP1.price + priceDiff;
-                    d.p2.time = this.startP2.time + timeDiff;
-                    d.p2.price = this.startP2.price + priceDiff;
-                } else if (d.time !== undefined && d.price !== undefined) {
-                    d.time = this.startTime + timeDiff;
-                    d.price = this.startPrice + priceDiff;
-                } else if (d.price !== undefined) {
-                    d.price = this.startPrice + priceDiff;
-                } else if (d.time !== undefined) {
-                    d.time = this.startTime + timeDiff;
+                
+                // If timeDiff is NaN (e.g., dragged into whitespace on high TF), estimate it
+                if (isNaN(timeDiff) || pos.time === null) {
+                     const timeScale = this.chart.timeScale();
+                     const startLogical = timeScale.coordinateToLogical(this.dragStartPos.x);
+                     const currentLogical = timeScale.coordinateToLogical(pos.x);
+                     if (startLogical !== null && currentLogical !== null) {
+                         const logicalDiff = currentLogical - startLogical;
+                         timeDiff = logicalDiff * this.getIntervalSeconds();
+                     }
+                }
+
+                if (!isNaN(timeDiff) && !isNaN(priceDiff)) {
+                    if (d.p1 && d.p2) {
+                        d.p1.time = this.startP1.time + timeDiff;
+                        d.p1.price = this.startP1.price + priceDiff;
+                        d.p2.time = this.startP2.time + timeDiff;
+                        d.p2.price = this.startP2.price + priceDiff;
+                    } else if (d.time !== undefined && d.price !== undefined) {
+                        d.time = this.startTime + timeDiff;
+                        d.price = this.startPrice + priceDiff;
+                    } else if (d.price !== undefined) {
+                        d.price = this.startPrice + priceDiff;
+                    } else if (d.time !== undefined) {
+                        d.time = this.startTime + timeDiff;
+                    }
                 }
             } else if (this.dragMode === 'price') {
                 d.price = pos.price;
@@ -391,11 +412,13 @@ export class DrawingManager {
             }
 
             if (d.p1 && d.p2) {
-                const x1 = this.chart.timeScale().timeToCoordinate(d.p1.time);
+                const x1 = this.chart.timeScale().timeToCoordinate(this.snapToNearestTime(d.p1.time));
                 const y1 = this.series.priceToCoordinate(d.p1.price);
-                const x2 = this.chart.timeScale().timeToCoordinate(d.p2.time);
+                const x2 = this.chart.timeScale().timeToCoordinate(this.snapToNearestTime(d.p2.time));
                 const y2 = this.series.priceToCoordinate(d.p2.price);
+                
                 if (x1 === null || y1 === null || x2 === null || y2 === null) continue;
+                
                 if (Math.hypot(x - x1, y - y1) < threshold) return { drawing: d, part: 'p1' };
                 if (Math.hypot(x - x2, y - y2) < threshold) return { drawing: d, part: 'p2' };
                 
@@ -409,10 +432,10 @@ export class DrawingManager {
                 const dy = this.series.priceToCoordinate(d.price);
                 if (Math.abs(y - dy) < threshold) return { drawing: d, part: 'price' };
             } else if (d.time !== undefined && d.type === 'vertical_line') {
-                const dx = this.chart.timeScale().timeToCoordinate(d.time);
+                const dx = this.chart.timeScale().timeToCoordinate(this.snapToNearestTime(d.time));
                 if (Math.abs(x - dx) < threshold) return { drawing: d, part: 'time' };
             } else if (d.time !== undefined && d.price !== undefined) {
-                const dx = this.chart.timeScale().timeToCoordinate(d.time);
+                const dx = this.chart.timeScale().timeToCoordinate(this.snapToNearestTime(d.time));
                 const dy = this.series.priceToCoordinate(d.price);
                 if (Math.hypot(x - dx, y - dy) < threshold) return { drawing: d, part: 'all' };
             }