From 415c172354bff731462a2135536a913ca5f688b4 Mon Sep 17 00:00:00 2001
From: John Whitington <john@coherentgraphics.co.uk>
Date: Mon, 22 Jan 2024 15:53:41 +0000
Subject: [PATCH] Adds -merge-no-struct-trees

---
 Changes        |  2 ++
 cpdfcommand.ml | 11 ++++++++++-
 cpdfmanual.tex |  1 +
 3 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/Changes b/Changes
index c28660b..4ceabea 100644
--- a/Changes
+++ b/Changes
@@ -32,6 +32,7 @@ o Report number of annotations in -page-info
 o Specify image based only on file extension
 o -squeeze updates old compression methods
 o Show page size summary in -info
+o Add -no-merge-struct-trees to prevent merging of structure trees
 
 Fixes:
 
@@ -40,6 +41,7 @@ o Fixed -set-annotations with page links
 o Allow Exif JPEGs as well as JFIF ones in -jpeg and -draw-jpeg
 o Only compress a stream if it actually makes it smaller
 
+
 2.6.1 (September 2023)
 
 o Fixed regression in UTF8 text with -add-text
diff --git a/cpdfcommand.ml b/cpdfcommand.ml
index 61c6b3a..77e11ce 100644
--- a/cpdfcommand.ml
+++ b/cpdfcommand.ml
@@ -459,6 +459,7 @@ type args =
    mutable boxes : bool;
    mutable encrypt_metadata : bool;
    mutable retain_numbering : bool;
+   mutable merge_struct_trees : bool;
    mutable remove_duplicate_fonts : bool;
    mutable remove_duplicate_streams : bool;
    mutable encoding : Cpdfmetadata.encoding;
@@ -593,6 +594,7 @@ let args =
    boxes = false;
    encrypt_metadata = true;
    retain_numbering = false;
+   merge_struct_trees = true;
    remove_duplicate_fonts = false;
    remove_duplicate_streams = false;
    encoding = Cpdfmetadata.UTF8;
@@ -732,6 +734,7 @@ let reset_arguments () =
   args.boxes <- false;
   args.encrypt_metadata <- true;
   args.retain_numbering <- false;
+  args.merge_struct_trees <- true;
   args.remove_duplicate_fonts <- false;
   args.remove_duplicate_streams <- false;
   args.encoding <- Cpdfmetadata.UTF8;
@@ -2013,6 +2016,9 @@ let setextractstreamdecomp i =
 let setprintobj i =
   args.op <- Some (PrintObj i)
 
+let setnomergestructtrees () =
+  args.merge_struct_trees <- false
+
 (* Parse a control file, make an argv, and then make Arg parse it. *)
 let rec make_control_argv_and_parse filename =
   control_args := !control_args @ parse_control_file filename
@@ -2129,6 +2135,9 @@ and specs =
    ("-merge-add-bookmarks-use-titles",
        Arg.Unit setmergeaddbookmarksusetitles,
        " Use title of document rather than filename");
+   ("-no-merge-struct-trees",
+       Arg.Unit setnomergestructtrees,
+       " Do not merge structure trees");
    ("-remove-duplicate-fonts",
        Arg.Unit set_remove_duplicate_fonts,
        " Remove duplicate fonts when merging");
@@ -3652,7 +3661,7 @@ let go () =
                         in
                         let outpdf =
                           Pdfmerge.merge_pdfs
-                            args.retain_numbering args.remove_duplicate_fonts names pdfs rangenums
+                            args.retain_numbering args.remove_duplicate_fonts ~struct_hierarchy:args.merge_struct_trees names pdfs rangenums
                         in
                           if args.remove_duplicate_streams then Pdfmerge.remove_duplicate_fonts outpdf; (* JBIG2 Globals *)
                           write_pdf false outpdf
diff --git a/cpdfmanual.tex b/cpdfmanual.tex
index 899df54..4a32394 100644
--- a/cpdfmanual.tex
+++ b/cpdfmanual.tex
@@ -15,6 +15,7 @@
 %Document -png -jpeg -jbig2 by extension
 %Document -extract-stream - check enc
 %Document -obj - check enc
+%Document -merge-no-struct-trees in merge and collate
 \documentclass{book}
 % Edit here to produce cpdfmanual.pdf, cpdflibmanual.pdf, pycpdfmanual.pdf,
 % dotnetcpdflibmanual.pdf, jcpdflibmanual.pdf jscpdflibmanual.pdf etc.