mergeDocument method

@override void mergeDocument(PdfDocument pdfDocument)

Imports the existing objects into the new PDF document.

Implementation

@override
void mergeDocument(PdfDocument pdfDocument) {
  _ensureXrefParsed();

  final trailer = _trailerInfo ??
      PdfParserXref.readTrailerInfoFromReader(reader, xrefOffset);
  if (trailer.rootObj == null) {
    pdfDocument.catalog = PdfCatalog(pdfDocument, PdfPageList(pdfDocument));
    return;
  }

  final rootObj = _getObject(trailer.rootObj!);
  if (rootObj == null || rootObj.value is! PdfDictToken) {
    pdfDocument.catalog = PdfCatalog(pdfDocument, PdfPageList(pdfDocument));
    return;
  }

  final rootDict = rootObj.value as PdfDictToken;
  final pagesRef =
      PdfParserObjects.asRef(rootDict.values[PdfNameTokens.pages]);

  final pageList = PdfPageList(
    pdfDocument,
    objser: pagesRef?.obj,
    objgen: pagesRef?.gen ?? 0,
  );

  pdfDocument.catalog = PdfCatalog(
    pdfDocument,
    pageList,
    objser: rootObj.objId,
    objgen: rootObj.gen,
  );

  PdfParserObjects.mergeDictIntoPdfDict(
    pdfDocument.catalog.params,
    rootDict,
    ignoreKeys: const {PdfNameTokens.pages, PdfNameTokens.type},
  );

  if (pagesRef != null) {
    // The `PdfPage` constructor already registers the page in
    // `pdfDocument.pdfPageList`. Appending the result again duplicated
    // every page: a two-page document came out with
    // `/Kids [3 0 R 22 0 R 3 0 R 22 0 R] /Count 4`.
    _loadPages(pagesRef, pdfDocument);
  }
}