From 094b522644d370e2fdcf3db73d563610b47ef7b4 Mon Sep 17 00:00:00 2001
From: AJ Isaacs <ajisaacs27@gmail.com>
Date: Fri, 27 Mar 2026 17:24:15 -0400
Subject: [PATCH] feat: add ColumnAttribute and CellExtensions for BOM parsing

---
 OpenNest.IO/Bom/CellExtensions.cs  | 23 +++++++++++++++++++++++
 OpenNest.IO/Bom/ColumnAttribute.cs | 15 +++++++++++++++
 2 files changed, 38 insertions(+)
 create mode 100644 OpenNest.IO/Bom/CellExtensions.cs
 create mode 100644 OpenNest.IO/Bom/ColumnAttribute.cs

diff --git a/OpenNest.IO/Bom/CellExtensions.cs b/OpenNest.IO/Bom/CellExtensions.cs
new file mode 100644
index 0000000..8d35afd
--- /dev/null
+++ b/OpenNest.IO/Bom/CellExtensions.cs
@@ -0,0 +1,23 @@
+using ClosedXML.Excel;
+
+namespace OpenNest.IO.Bom
+{
+    public static class CellExtensions
+    {
+        public static int? ToIntOrNull(this IXLCell cell)
+        {
+            if (cell.IsEmpty()) return null;
+            if (cell.DataType == XLDataType.Number) return (int)cell.GetDouble();
+            if (int.TryParse(cell.GetString(), out var i)) return i;
+            return null;
+        }
+
+        public static double? ToDoubleOrNull(this IXLCell cell)
+        {
+            if (cell.IsEmpty()) return null;
+            if (cell.DataType == XLDataType.Number) return cell.GetDouble();
+            if (double.TryParse(cell.GetString(), out var result)) return result;
+            return null;
+        }
+    }
+}
diff --git a/OpenNest.IO/Bom/ColumnAttribute.cs b/OpenNest.IO/Bom/ColumnAttribute.cs
new file mode 100644
index 0000000..7b1e5a0
--- /dev/null
+++ b/OpenNest.IO/Bom/ColumnAttribute.cs
@@ -0,0 +1,15 @@
+using System;
+
+namespace OpenNest.IO.Bom
+{
+    [AttributeUsage(AttributeTargets.Property)]
+    public class ColumnAttribute : Attribute
+    {
+        public ColumnAttribute(params string[] names)
+        {
+            Names = names;
+        }
+
+        public string[] Names { get; }
+    }
+}