feat: add IDrawingInfoExtractor with equipment and default implementations

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ExportDXF/Services/DefaultDrawingInfoExtractor.cs

@@ -0,0 +1,28 @@
+using System.Configuration;
+using System.IO;
+
+namespace ExportDXF.Services
+{
+    /// <summary>
+    /// Fallback extractor that uses the document name as prefix
+    /// and appends the configured default suffix.
+    /// Always returns true — this is the catch-all.
+    /// </summary>
+    public class DefaultDrawingInfoExtractor : IDrawingInfoExtractor
+    {
+        public bool TryExtract(string documentName, out DrawingInfoResult info)
+        {
+            var name = Path.GetFileNameWithoutExtension(documentName);
+            var suffix = ConfigurationManager.AppSettings["DefaultSuffix"] ?? "PT{item_no:2}";
+
+            info = new DrawingInfoResult
+            {
+                EquipmentNumber = null,
+                DrawingNumber = null,
+                DefaultTemplate = $"{name} {suffix}"
+            };
+
+            return true;
+        }
+    }
+}

ExportDXF/Services/EquipmentDrawingInfoExtractor.cs

@@ -0,0 +1,36 @@
+using System.IO;
+
+namespace ExportDXF.Services
+{
+    /// <summary>
+    /// Extracts equipment/drawing numbers from document names matching the
+    /// workplace format (e.g., "4321 A01.SLDDRW" → equipment "4321", drawing "A01").
+    /// Uses the existing DrawingInfo.Parse() logic.
+    /// </summary>
+    public class EquipmentDrawingInfoExtractor : IDrawingInfoExtractor
+    {
+        public bool TryExtract(string documentName, out DrawingInfoResult info)
+        {
+            info = null;
+
+            var name = Path.GetFileNameWithoutExtension(documentName);
+            var parsed = DrawingInfo.Parse(name);
+
+            if (parsed == null || string.IsNullOrEmpty(parsed.EquipmentNo))
+                return false;
+
+            var template = !string.IsNullOrEmpty(parsed.DrawingNo)
+                ? $"{parsed.EquipmentNo} {parsed.DrawingNo} PT{{item_no:2}}"
+                : $"{parsed.EquipmentNo} PT{{item_no:2}}";
+
+            info = new DrawingInfoResult
+            {
+                EquipmentNumber = parsed.EquipmentNo,
+                DrawingNumber = parsed.DrawingNo,
+                DefaultTemplate = template
+            };
+
+            return true;
+        }
+    }
+}

ExportDXF/Services/IDrawingInfoExtractor.cs

@@ -0,0 +1,14 @@
+namespace ExportDXF.Services
+{
+    public interface IDrawingInfoExtractor
+    {
+        bool TryExtract(string documentName, out DrawingInfoResult info);
+    }
+
+    public class DrawingInfoResult
+    {
+        public string EquipmentNumber { get; set; }
+        public string DrawingNumber { get; set; }
+        public string DefaultTemplate { get; set; }
+    }
+}