update 20260326

Versandstrasse/Class1.cs

@@ -1,4 +1,11 @@
-using System;
+using edoka_dms;
+using Model;
+using Syncfusion.Pdf;
+using Syncfusion.Pdf.Graphics;
+using Syncfusion.Pdf.Graphics.Fonts;
+using Syncfusion.Pdf.Parsing;
+using Syncfusion.XPS;
+using System;
 using System.Collections.Generic;
 using System.Data.SqlClient;
 using System.Data.SqlTypes;
@@ -17,14 +24,8 @@ using System.Security.Policy;
 using System.Security.Principal;
 using System.Text;
 using System.Threading.Tasks;
+using System.Xml.Linq;
 using System.Xml.Serialization;
-using edoka_dms;
-using Model;
-using Syncfusion.Pdf;
-using Syncfusion.Pdf.Graphics;
-using Syncfusion.Pdf.Graphics.Fonts;
-using Syncfusion.Pdf.Parsing;
-using Syncfusion.XPS;
 
 
 namespace Versandstrasse
@@ -90,11 +91,121 @@ namespace Versandstrasse
            // inhalt = DateTime.Now + " / " + inhalt;
             //System.IO.File.AppendAllText(@"h:\edoka_work\vs.log", Environment.NewLine + inhalt);
         }
+        public string FixPageBreaks(string base64Pdf)
+        {
+            byte[] inputBytes = Convert.FromBase64String(base64Pdf);
+
+            using (MemoryStream inputStream = new MemoryStream(inputBytes))
+            using (MemoryStream outputStream = new MemoryStream())
+            {
+                PdfLoadedDocument loadedDoc = new PdfLoadedDocument(inputStream);
+
+                int lastBreakIndex = 0;
+                PageOrientation? lastOrientation = null;
+
+                int i = 0;
+                while (i < loadedDoc.Pages.Count)
+                {
+                    PdfLoadedPage page = loadedDoc.Pages[i] as PdfLoadedPage;
+
+                    var size = page.Size;
+                    var rotation = page.Rotation;
+
+                    bool isLandscape = IsLandscape(size.Width, size.Height, rotation);
+                    var currentOrientation = isLandscape ? PageOrientation.Landscape : PageOrientation.Portrait;
+
+                    if (lastOrientation == null)
+                    {
+                        lastOrientation = currentOrientation;
+                        i++;
+                        continue;
+                    }
+
+                    // Wechsel erkannt
+                    if (currentOrientation != lastOrientation)
+                    {
+                        int pagesSinceBreak = i - lastBreakIndex;
+
+                        if (pagesSinceBreak % 2 != 0)
+                        {
+                            // Leere Seite mit gleicher Größe wie vorherige Seite einfügen
+                            PdfLoadedPage prevPage = loadedDoc.Pages[i - 1] as PdfLoadedPage;
+                            var prevSize = prevPage.Size;
+
+                            loadedDoc.Pages.Insert(i, prevSize);
+
+                            i++; // überspringe eingefügte Seite
+                        }
+
+                        lastBreakIndex = i;
+                        lastOrientation = currentOrientation;
+                    }
+
+                    i++;
+                }
+
+                // 🔥 NEU: Prüfung nach letztem Umbruch
+                int remainingPages = loadedDoc.Pages.Count - lastBreakIndex;
+
+                if (remainingPages % 2 != 0 && loadedDoc.Pages.Count > 0)
+                {
+                    PdfLoadedPage lastPage = loadedDoc.Pages[loadedDoc.Pages.Count - 1] as PdfLoadedPage;
+                    var lastSize = lastPage.Size;
+
+                    loadedDoc.Pages.Add(lastSize);
+                }
+
+                loadedDoc.Save(outputStream);
+                loadedDoc.Close(true);
+
+                return Convert.ToBase64String(outputStream.ToArray());
+            }
+        }
+
+
+
+        private  bool IsLandscape(float width, float height, PdfPageRotateAngle rotation)
+        {
+            bool landscape = width > height;
+
+            // Rotation berücksichtigen (90° / 270° drehen Orientierung)
+            if (rotation == PdfPageRotateAngle.RotateAngle90 ||
+                rotation == PdfPageRotateAngle.RotateAngle270)
+            {
+                landscape = !landscape;
+            }
+
+            return landscape;
+        }
+
+        // =========================================================
+        // 📄 A4 erkennen (mit Toleranz)
+        // =========================================================
+        private  bool IsA4(PdfLoadedPage page)
+        {
+            const float tolerance = 5f;
+
+            float w = page.Size.Width;
+            float h = page.Size.Height;
+
+            return
+                (Math.Abs(w - 842f) < tolerance && Math.Abs(h - 595f) < tolerance) ||
+                (Math.Abs(w - 595f) < tolerance && Math.Abs(h - 842f) < tolerance);
+        }
+
+        enum PageOrientation
+        {
+            Portrait,
+            Landscape
+        }
 
         public string check_pdf_pages(string dokument)
         {
+            return FixPageBreaks(dokument);
+
             var stream = new MemoryStream(Convert.FromBase64String(dokument));
             PdfLoadedDocument loadedDocument = new PdfLoadedDocument(stream);
+           
             if (loadedDocument.Pages.Count % 2 == 0) { } else { Add_EmptyPage(ref loadedDocument); }
             MemoryStream outputStream = new MemoryStream();
             string dok = "";
@@ -608,6 +719,7 @@ namespace Versandstrasse
 
 
         }
+
         private void Add_EmptyPage(ref PdfLoadedDocument document)
         {