private static DictionaryToken ParseTrailer(CrossReferenceTable crossReferenceTable, bool isLenientParsing, IPdfTokenScanner pdfTokenScanner,
out EncryptionDictionary encryptionDictionary)
{
encryptionDictionary = null;
if (crossReferenceTable.Trailer.EncryptionToken != null)
{
if (!DirectObjectFinder.TryGet(crossReferenceTable.Trailer.EncryptionToken, pdfTokenScanner, out DictionaryToken encryptionDictionaryToken))
{
throw new PdfDocumentFormatException($"Unrecognized encryption token in trailer: {crossReferenceTable.Trailer.EncryptionToken}.");
}
encryptionDictionary = EncryptionDictionaryFactory.Read(encryptionDictionaryToken, pdfTokenScanner);
//throw new NotSupportedException("Cannot currently parse a document using encryption: " + crossReferenceTable.Trailer.EncryptionToken);
}
var rootDictionary = DirectObjectFinder.Get <DictionaryToken>(crossReferenceTable.Trailer.Root, pdfTokenScanner);
if (!rootDictionary.ContainsKey(NameToken.Type) && isLenientParsing)
{
rootDictionary = rootDictionary.With(NameToken.Type, NameToken.Catalog);
}
return(rootDictionary);
}
// This method is a basically a copy of the method UglyToad.PdfPig.Parser.PdfDocumentFactory.ParseTrailer()
private static DictionaryToken ParseCatalog(CrossReferenceTable crossReferenceTable,
IPdfTokenScanner pdfTokenScanner,
out EncryptionDictionary encryptionDictionary)
{
encryptionDictionary = null;
if (crossReferenceTable.Trailer.EncryptionToken != null)
{
if (!DirectObjectFinder.TryGet(crossReferenceTable.Trailer.EncryptionToken, pdfTokenScanner,
out DictionaryToken encryptionDictionaryToken))
{
throw new PdfDocumentFormatException($"Unrecognized encryption token in trailer: {crossReferenceTable.Trailer.EncryptionToken}.");
}
encryptionDictionary = EncryptionDictionaryFactory.Read(encryptionDictionaryToken, pdfTokenScanner);
}
var rootDictionary = DirectObjectFinder.Get <DictionaryToken>(crossReferenceTable.Trailer.Root, pdfTokenScanner);
if (!rootDictionary.ContainsKey(NameToken.Type))
{
rootDictionary = rootDictionary.With(NameToken.Type, NameToken.Catalog);
}
return(rootDictionary);
}
private static EncryptionDictionary GetEncryptionDictionary(CrossReferenceTable crossReferenceTable, IPdfTokenScanner pdfTokenScanner)
{
if (crossReferenceTable.Trailer.EncryptionToken == null)
{
return(null);
}
if (!DirectObjectFinder.TryGet(crossReferenceTable.Trailer.EncryptionToken, pdfTokenScanner, out DictionaryToken encryptionDictionaryToken))
{
if (DirectObjectFinder.TryGet(crossReferenceTable.Trailer.EncryptionToken, pdfTokenScanner, out NullToken _))
{
return(null);
}
throw new PdfDocumentFormatException($"Unrecognized encryption token in trailer: {crossReferenceTable.Trailer.EncryptionToken}.");
}
var result = EncryptionDictionaryFactory.Read(encryptionDictionaryToken, pdfTokenScanner);
return(result);
}
