From 3022982f6dcbbccf55285ee9f7227e5c7c401a2d Mon Sep 17 00:00:00 2001
From: AJ Isaacs <ajisaacs27@gmail.com>
Date: Sat, 28 Mar 2026 16:22:00 -0400
Subject: [PATCH] refactor: consolidate HasOverlappingParts into FillHelpers

StripeFiller and FillExtents had identical 24-line overlap detection
methods; move to FillHelpers and delegate from both callers.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 OpenNest.Engine/Fill/FillExtents.cs       | 28 +++-----------------
 OpenNest.Engine/Fill/StripeFiller.cs      | 31 ++---------------------
 OpenNest.Engine/Strategies/FillHelpers.cs | 30 ++++++++++++++++++++++
 3 files changed, 35 insertions(+), 54 deletions(-)

diff --git a/OpenNest.Engine/Fill/FillExtents.cs b/OpenNest.Engine/Fill/FillExtents.cs
index 76380b4..0c09a77 100644
--- a/OpenNest.Engine/Fill/FillExtents.cs
+++ b/OpenNest.Engine/Fill/FillExtents.cs
@@ -1,3 +1,4 @@
+using OpenNest.Engine.Strategies;
 using OpenNest.Geometry;
 using OpenNest.Math;
 using System;
@@ -411,30 +412,7 @@ namespace OpenNest.Engine.Fill
                    part.BoundingBox.Bottom >= workArea.Bottom - Tolerance.Epsilon;
         }
 
-        private static bool HasOverlappingParts(List<Part> parts)
-        {
-            for (var i = 0; i < parts.Count; i++)
-            {
-                var b1 = parts[i].BoundingBox;
-
-                for (var j = i + 1; j < parts.Count; j++)
-                {
-                    var b2 = parts[j].BoundingBox;
-
-                    var overlapX = System.Math.Min(b1.Right, b2.Right)
-                                 - System.Math.Max(b1.Left, b2.Left);
-                    var overlapY = System.Math.Min(b1.Top, b2.Top)
-                                 - System.Math.Max(b1.Bottom, b2.Bottom);
-
-                    if (overlapX <= Tolerance.Epsilon || overlapY <= Tolerance.Epsilon)
-                        continue;
-
-                    if (parts[i].Intersects(parts[j], out _))
-                        return true;
-                }
-            }
-
-            return false;
-        }
+        private static bool HasOverlappingParts(List<Part> parts) =>
+            FillHelpers.HasOverlappingParts(parts);
     }
 }
diff --git a/OpenNest.Engine/Fill/StripeFiller.cs b/OpenNest.Engine/Fill/StripeFiller.cs
index f8eb126..f882b02 100644
--- a/OpenNest.Engine/Fill/StripeFiller.cs
+++ b/OpenNest.Engine/Fill/StripeFiller.cs
@@ -481,33 +481,6 @@ public class StripeFiller
         return axis == NestDirection.Horizontal ? box.Width : box.Length;
     }
 
-    /// <summary>
-    /// Checks if any pair of parts geometrically overlap. Uses bounding box
-    /// pre-filtering for performance, then falls back to shape intersection.
-    /// </summary>
-    private static bool HasOverlappingParts(List<Part> parts)
-    {
-        for (var i = 0; i < parts.Count; i++)
-        {
-            var b1 = parts[i].BoundingBox;
-
-            for (var j = i + 1; j < parts.Count; j++)
-            {
-                var b2 = parts[j].BoundingBox;
-
-                var overlapX = System.Math.Min(b1.Right, b2.Right)
-                             - System.Math.Max(b1.Left, b2.Left);
-                var overlapY = System.Math.Min(b1.Top, b2.Top)
-                             - System.Math.Max(b1.Bottom, b2.Bottom);
-
-                if (overlapX <= Tolerance.Epsilon || overlapY <= Tolerance.Epsilon)
-                    continue;
-
-                if (parts[i].Intersects(parts[j], out _))
-                    return true;
-            }
-        }
-
-        return false;
-    }
+    private static bool HasOverlappingParts(List<Part> parts) =>
+        FillHelpers.HasOverlappingParts(parts);
 }
diff --git a/OpenNest.Engine/Strategies/FillHelpers.cs b/OpenNest.Engine/Strategies/FillHelpers.cs
index a2873e0..db541b9 100644
--- a/OpenNest.Engine/Strategies/FillHelpers.cs
+++ b/OpenNest.Engine/Strategies/FillHelpers.cs
@@ -109,5 +109,35 @@ namespace OpenNest.Engine.Strategies
             var fallback = fillFunc(other);
             return fallback ?? new List<Part>();
         }
+
+        /// <summary>
+        /// Checks if any pair of parts geometrically overlap. Uses bounding box
+        /// pre-filtering for performance, then falls back to shape intersection.
+        /// </summary>
+        internal static bool HasOverlappingParts(List<Part> parts)
+        {
+            for (var i = 0; i < parts.Count; i++)
+            {
+                var b1 = parts[i].BoundingBox;
+
+                for (var j = i + 1; j < parts.Count; j++)
+                {
+                    var b2 = parts[j].BoundingBox;
+
+                    var overlapX = System.Math.Min(b1.Right, b2.Right)
+                                 - System.Math.Max(b1.Left, b2.Left);
+                    var overlapY = System.Math.Min(b1.Top, b2.Top)
+                                 - System.Math.Max(b1.Bottom, b2.Bottom);
+
+                    if (overlapX <= Tolerance.Epsilon || overlapY <= Tolerance.Epsilon)
+                        continue;
+
+                    if (parts[i].Intersects(parts[j], out _))
+                        return true;
+                }
+            }
+
+            return false;
+        }
     }
 }