Added option to split PDF into multiple parts and merge into one PDF (#841)

* Added option to split PDF into multiple parts and merge into one PDF

* Use the mergeDocuments method in MergeController to implement merging

---------

Co-authored-by: Eric <71648843+sbplat@users.noreply.github.com>

src/main/java/stirling/software/SPDF/controller/api/MergeController.java

@@ -38,7 +38,7 @@ public class MergeController {
 
     private static final Logger logger = LoggerFactory.getLogger(MergeController.class);
 
-    private PDDocument mergeDocuments(List<PDDocument> documents) throws IOException {
+    public PDDocument mergeDocuments(List<PDDocument> documents) throws IOException {
         PDDocument mergedDoc = new PDDocument();
         for (PDDocument doc : documents) {
             for (PDPage page : doc.getPages()) {

src/main/java/stirling/software/SPDF/controller/api/SplitPdfBySectionsController.java

@@ -53,8 +53,21 @@ public class SplitPdfBySectionsController {
         // Process the PDF based on split parameters
         int horiz = request.getHorizontalDivisions() + 1;
         int verti = request.getVerticalDivisions() + 1;
-
+        boolean merge = request.isMerge();
         List<PDDocument> splitDocuments = splitPdfPages(sourceDocument, verti, horiz);
+
+        String filename =
+                Filenames.toSimpleFileName(file.getOriginalFilename())
+                        .replaceFirst("[.][^.]+$", "");
+        if (merge) {
+            MergeController mergeController = new MergeController();
+            ByteArrayOutputStream baos = new ByteArrayOutputStream();
+            mergeController.mergeDocuments(splitDocuments).save(baos);
+            return WebResponseUtils.bytesToWebResponse(
+                    baos.toByteArray(),
+                    filename + "_split.pdf",
+                    MediaType.APPLICATION_OCTET_STREAM);
+        }
         for (PDDocument doc : splitDocuments) {
             ByteArrayOutputStream baos = new ByteArrayOutputStream();
             doc.save(baos);
@@ -65,9 +78,6 @@ public class SplitPdfBySectionsController {
         sourceDocument.close();
 
         Path zipFile = Files.createTempFile("split_documents", ".zip");
-        String filename =
-                Filenames.toSimpleFileName(file.getOriginalFilename())
-                        .replaceFirst("[.][^.]+$", "");
         byte[] data;
 
         try (ZipOutputStream zipOut = new ZipOutputStream(Files.newOutputStream(zipFile))) {
@@ -145,4 +155,5 @@ public class SplitPdfBySectionsController {
 
         return splitDocuments;
     }
+
 }

src/main/java/stirling/software/SPDF/model/api/SplitPdfBySectionsRequest.java

@@ -15,4 +15,7 @@ public class SplitPdfBySectionsRequest extends PDFFile {
 
     @Schema(description = "Number of vertical divisions for each PDF page", example = "2")
     private int verticalDivisions;
+
+    @Schema(description = "Merge the split documents into a single PDF", example = "true")
+    private boolean merge;
 }