/// <summary>
/// Processes two cases of object copying:
/// <list type="number">
/// <item><description>copying to the other document
/// </description></item>
/// <item><description>cloning inside of the current document
/// </description></item>
/// </list>
/// </summary>
/// <remarks>
/// Processes two cases of object copying:
/// <list type="number">
/// <item><description>copying to the other document
/// </description></item>
/// <item><description>cloning inside of the current document
/// </description></item>
/// </list>
/// <para />
/// This two cases are distinguished by the state of
/// <c>document</c>
/// parameter:
/// the second case is processed if
/// <c>document</c>
/// is
/// <see langword="null"/>.
/// </remarks>
/// <param name="documentTo">if not null: document to copy object to; otherwise indicates that object is to be cloned.
/// </param>
/// <param name="allowDuplicating">
/// indicates if to allow copy objects which already have been copied.
/// If object is associated with any indirect reference and allowDuplicating is false then already existing reference will be returned instead of copying object.
/// If allowDuplicating is true then object will be copied and new indirect reference will be assigned.
/// </param>
/// <returns>copied object.</returns>
internal virtual PdfObject ProcessCopying(PdfDocument documentTo, bool allowDuplicating)
{
if (documentTo != null)
{
//copyTo case
PdfWriter writer = documentTo.GetWriter();
if (writer == null)
{
throw new PdfException(PdfException.CannotCopyToDocumentOpenedInReadingMode);
}
return(writer.CopyObject(this, documentTo, allowDuplicating));
}
else
{
//clone case
PdfObject obj = this;
if (obj.IsIndirectReference())
{
PdfObject refTo = ((PdfIndirectReference)obj).GetRefersTo();
obj = refTo != null ? refTo : obj;
}
if (obj.IsIndirect() && !allowDuplicating)
{
return(obj);
}
return(obj.Clone());
}
}
