public PdfReference GetIndirectReference(PdfCrossReference xref)
{
return(new PdfReference(this)
{
ObjectNumber = xref.ObjectNumber, Generation = xref.Generation
});
}
private void WriteIndirectObject(PdfCrossReference obj)
{
if (obj.EntryType != XrefEntryType.Used)
{
return;
}
AsciiToOutput($"{obj.ObjectNumber} {obj.Generation} obj\n");
WriteObject(obj.Object);
AsciiToOutput("\nendobj\n");
}
private PdfCrossReference ParseFromStream(PdfCrossReference indirectObj)
{
PdfCrossReference streamObjRef = _doc.Xref.Get(indirectObj.StreamObjectNumber, 0);
if (streamObjRef == null || streamObjRef.EntryType != XrefEntryType.Used)
{
throw new Exception("Indirect object stream could not be found");
}
ParseIndirectObjectDefinition(streamObjRef);
var objectStream = streamObjRef.Object as ObjectStream;
indirectObj.Object = objectStream[indirectObj.Offset];
indirectObj.Loaded = true;
return(indirectObj);
}
private IPdfStream SetObjectType(PdfCrossReference xref, PdfStream stream)
{
if (!stream.Dict.ContainsKey("/Type"))
{
return(stream);
}
string objType = stream.Dict.Get <PdfName>("/Type").Name;
switch (objType)
{
case "/XRef": return(new XrefObject(stream, xref.ObjectNumber));
case "/ObjStm": return(new ObjectStream(_doc, stream));
case "/XObject": return(new XObject(stream));
default: return(stream);
}
}
internal IPdfObject ResolveReference(PdfReference reference)
{
PdfCrossReference indirectObj = Xref.Get(reference.ObjectNumber, reference.Generation);
if (indirectObj == null)
{
return(null);
}
if (!indirectObj.Loaded)
{
Parser.ParseIndirectObjectDefinition(indirectObj);
}
IPdfObject obj = indirectObj.Object;
if (obj is PdfReference)
{
return(ResolveReference(obj as PdfReference));
}
return(obj);
}
// For some objects it is useful to have access to special properties for access or manipulation.
// Those are selected from the /Type here
private IPdfObject SetObjectType(PdfCrossReference xref, PdfDictionary dict)
{
if (dict.ContainsKey("/Type"))
{
string objType = dict.Get <PdfName>("/Type").Name;
switch (objType)
{
case "/Catalog": return(new Catalog(dict));
case "/Pages": return(new Pages(dict));
case "/Page": return(new Page(dict));
case "/Font": return(new Font(dict));
}
}
if (xref.ObjectNumber == _doc.Trailer.Info.ObjectNumber && xref.Generation == _doc.Trailer.Info.Generation)
{
return(new InformationDictionary(dict));
}
return(dict);
}
protected internal void Write(PdfIndirectObject indirect, int refNumber)
{
PdfCrossReference pxref = new PdfCrossReference(refNumber, position);
xrefs.Remove(pxref);
xrefs[pxref] = null;
indirect.WriteTo(writer.Os);
position = writer.Os.Counter;
}
internal PdfIndirectObject Add(PdfObject objecta, int refNumber, bool inObjStm)
{
if (inObjStm && objecta.CanBeInObjStm() && writer.FullCompression) {
PdfCrossReference pxref = AddToObjStm(objecta, refNumber);
PdfIndirectObject indirect = new PdfIndirectObject(refNumber, objecta, writer);
xrefs.Remove(pxref);
xrefs[pxref] = null;
return indirect;
}
else {
PdfIndirectObject indirect = new PdfIndirectObject(refNumber, objecta, writer);
PdfCrossReference pxref = new PdfCrossReference(refNumber, position);
xrefs.Remove(pxref);
xrefs[pxref] = null;
indirect.WriteTo(writer.Os);
position = writer.Os.Counter;
return indirect;
}
}
internal PdfCrossReference ParseIndirectObjectDefinition(PdfCrossReference indirectObj)
{
int offset = -1;
if (indirectObj == null)
{
offset = _lexer.Current.Offset;
}
else
{
if (indirectObj.Loaded)
{
return(indirectObj);
}
// Entry points to an indirect object stream - resolve that.
if (indirectObj != null && indirectObj.EntryType == XrefEntryType.InStream)
{
return(ParseFromStream(indirectObj));
}
_lexer.Seek(indirectObj.Offset);
_lexer.Next();
Expect(TokenType.Integer);
}
int objectNumber = (int)_lexer.Current.Value;
_lexer.Next();
Expect(TokenType.Integer);
int generation = (int)_lexer.Current.Value;
if (indirectObj == null)
{
indirectObj = new PdfCrossReference()
{
EntryType = XrefEntryType.Used, ObjectNumber = objectNumber, Generation = generation, Offset = offset
}
}
;
else if (objectNumber != indirectObj.ObjectNumber || generation != indirectObj.Generation)
{
throw new ParserException($"Expecting object {indirectObj.ObjectNumber} {indirectObj.Generation} at offset {indirectObj.Offset} but got {objectNumber} {generation}");
}
_lexer.Next();
Expect(TokenType.Object);
IPdfObject obj = ParseObject();
_lexer.Next();
if (Accept(TokenType.Stream))
{
if (!(obj is PdfDictionary))
{
throw new ParserException("Stream objects must be preceded by a dictionary");
}
obj = SetObjectType(indirectObj, ParseStream(obj as PdfDictionary));
_lexer.Next();
}
else if (obj is PdfDictionary)
{
obj = SetObjectType(indirectObj, obj as PdfDictionary);
}
Expect(TokenType.EndObject);
indirectObj.Object = obj;
indirectObj.Loaded = true;
return(indirectObj);
}
