private static int SeparateStructure(PdfDocument document, int startPage, int beforePage, int startPageStructTopIndex
) {
if (!document.IsTagged() || 1 > startPage || startPage > beforePage || beforePage > document.GetNumberOfPages
() + 1) {
return -1;
}
else {
if (beforePage == startPage) {
return startPageStructTopIndex;
}
else {
if (beforePage == document.GetNumberOfPages() + 1) {
return document.GetStructTreeRoot().GetKidsObject().Size();
}
}
}
// Here we separate the structure tree in two parts: struct elems that belong to the pages which indexes are
// less then separateBeforePage and those struct elems that belong to other pages. Some elems might belong
// to both parts and actually these are the ones that we are looking for.
ICollection<PdfObject> firstPartElems = new HashSet<PdfObject>();
for (int i = startPage; i < beforePage; ++i) {
PdfPage pageOfFirstHalf = document.GetPage(i);
ICollection<PdfMcr> pageMcrs = document.GetStructTreeRoot().GetPageMarkedContentReferences(pageOfFirstHalf
);
if (pageMcrs != null) {
foreach (PdfMcr mcr in pageMcrs) {
firstPartElems.Add(mcr.GetPdfObject());
PdfDictionary top = AddAllParentsToSet(mcr, firstPartElems);
if (top != null && top.IsFlushed()) {
throw new PdfException(PdfException.TagFromTheExistingTagStructureIsFlushedCannotAddCopiedPageTags);
}
}
}
}
IList<PdfDictionary> clonedTops = new List<PdfDictionary>();
PdfArray tops = document.GetStructTreeRoot().GetKidsObject();
// Now we "walk" through all the elems which belong to the first part, and look for the ones that contain both
// kids from first and second part. We clone found elements and move kids from the second part to cloned elems.
int lastTopBefore = startPageStructTopIndex - 1;
for (int i = 0; i < tops.Size(); ++i) {
PdfDictionary top = tops.GetAsDictionary(i);
if (firstPartElems.Contains(top)) {
lastTopBefore = i;
StructureTreeCopier.LastClonedAncestor lastCloned = new StructureTreeCopier.LastClonedAncestor();
lastCloned.ancestor = top;
PdfDictionary topClone = top.Clone(ignoreKeysForClone);
topClone.Put(PdfName.P, document.GetStructTreeRoot().GetPdfObject());
lastCloned.clone = topClone;
SeparateKids(top, firstPartElems, lastCloned, document);
if (topClone.ContainsKey(PdfName.K)) {
topClone.MakeIndirect(document);
clonedTops.Add(topClone);
}
}
}
for (int i = 0; i < clonedTops.Count; ++i) {
document.GetStructTreeRoot().AddKidObject(lastTopBefore + 1 + i, clonedTops[i]);
}
return lastTopBefore + 1;
}
private static void CloneParents(PdfDictionary structElem, StructureTreeCopier.LastClonedAncestor lastCloned
, PdfDocument document) {
if (lastCloned.ancestor != structElem) {
PdfDictionary structElemClone = (PdfDictionary)structElem.Clone(ignoreKeysForClone).MakeIndirect(document);
PdfDictionary currClone = structElemClone;
PdfDictionary currElem = structElem;
while (currElem.Get(PdfName.P) != lastCloned.ancestor) {
PdfDictionary parent = currElem.GetAsDictionary(PdfName.P);
PdfDictionary parentClone = (PdfDictionary)parent.Clone(ignoreKeysForClone).MakeIndirect(document);
currClone.Put(PdfName.P, parentClone);
parentClone.Put(PdfName.K, currClone);
currClone = parentClone;
currElem = parent;
}
PdfStructElem.AddKidObject(lastCloned.clone, -1, currClone);
lastCloned.clone = structElemClone;
lastCloned.ancestor = structElem;
}
}
private static void SeparateKids(PdfDictionary structElem, ICollection <PdfObject> firstPartElems, StructureTreeCopier.LastClonedAncestor
lastCloned)
{
PdfObject k = structElem.Get(PdfName.K);
// If /K entry is not a PdfArray - it would be a kid which we won't clone at the moment, because it won't contain
// kids from both parts at the same time. It would either be cloned as an ancestor later, or not cloned at all.
// If it's kid is struct elem - it would definitely be structElem from the first part, so we simply call separateKids for it.
if (!k.IsArray())
{
if (k.IsDictionary() && PdfStructElem.IsStructElem((PdfDictionary)k))
{
SeparateKids((PdfDictionary)k, firstPartElems, lastCloned);
}
}
else
{
PdfDocument document = structElem.GetIndirectReference().GetDocument();
PdfArray kids = (PdfArray)k;
for (int i = 0; i < kids.Size(); ++i)
{
PdfObject kid = kids.Get(i);
PdfDictionary dictKid = null;
if (kid.IsDictionary())
{
dictKid = (PdfDictionary)kid;
}
if (dictKid != null && PdfStructElem.IsStructElem(dictKid))
{
if (firstPartElems.Contains(kid))
{
SeparateKids((PdfDictionary)kid, firstPartElems, lastCloned);
}
else
{
if (dictKid.IsFlushed())
{
throw new PdfException(PdfException.TagFromTheExistingTagStructureIsFlushedCannotAddCopiedPageTags);
}
// elems with no kids will not be marked as from the first part,
// but nonetheless we don't want to move all of them to the second part; we just leave them as is
if (dictKid.ContainsKey(PdfName.K))
{
CloneParents(structElem, lastCloned, document);
kids.Remove(i--);
PdfStructElem.AddKidObject(lastCloned.clone, -1, kid);
}
}
}
else
{
if (!firstPartElems.Contains(kid))
{
CloneParents(structElem, lastCloned, document);
PdfMcr mcr;
if (dictKid != null)
{
if (dictKid.Get(PdfName.Type).Equals(PdfName.MCR))
{
mcr = new PdfMcrDictionary(dictKid, new PdfStructElem(lastCloned.clone));
}
else
{
mcr = new PdfObjRef(dictKid, new PdfStructElem(lastCloned.clone));
}
}
else
{
mcr = new PdfMcrNumber((PdfNumber)kid, new PdfStructElem(lastCloned.clone));
}
kids.Remove(i--);
PdfStructElem.AddKidObject(lastCloned.clone, -1, kid);
document.GetStructTreeRoot().GetParentTreeHandler().RegisterMcr(mcr);
}
}
}
}
// re-register mcr
if (lastCloned.ancestor == structElem)
{
lastCloned.ancestor = lastCloned.ancestor.GetAsDictionary(PdfName.P);
lastCloned.clone = lastCloned.clone.GetAsDictionary(PdfName.P);
}
}
/// <summary>
/// Copies structure to a
/// <paramref name="destDocument"/>
/// and insert it in a specified position in the document.
/// <br/><br/>
/// NOTE: Works only for
/// <c>PdfStructTreeRoot</c>
/// that is read from the document opened in reading mode,
/// otherwise an exception is thrown.
/// <br/>
/// Also, to insert a tagged page into existing tag structure, existing tag structure shouldn't be flushed, otherwise
/// an exception may be raised.
/// </summary>
/// <param name="destDocument">document to copy structure to.</param>
/// <param name="insertBeforePage">indicates where the structure to be inserted.</param>
/// <param name="page2page">association between original page and copied page.</param>
public static void CopyTo(PdfDocument destDocument, int insertBeforePage, IDictionary <PdfPage, PdfPage> page2page
, PdfDocument callingDocument)
{
if (!destDocument.IsTagged())
{
return;
}
// Here we separate the structure tree in two parts: struct elems that belong to the pages which indexes are
// less then insertBeforePage and those struct elems that belong to other pages. Some elems might belong
// to both parts and actually these are the ones that we are looking for.
ICollection <PdfObject> firstPartElems = new HashSet <PdfObject>();
PdfStructTreeRoot destStructTreeRoot = destDocument.GetStructTreeRoot();
for (int i = 1; i < insertBeforePage; ++i)
{
PdfPage pageOfFirstHalf = destDocument.GetPage(i);
ICollection <PdfMcr> pageMcrs = destStructTreeRoot.GetPageMarkedContentReferences(pageOfFirstHalf);
if (pageMcrs != null)
{
foreach (PdfMcr mcr in pageMcrs)
{
firstPartElems.Add(mcr.GetPdfObject());
PdfDictionary top = AddAllParentsToSet(mcr, firstPartElems);
if (top.IsFlushed())
{
throw new PdfException(PdfException.TagFromTheExistingTagStructureIsFlushedCannotAddCopiedPageTags);
}
}
}
}
IList <PdfDictionary> clonedTops = new List <PdfDictionary>();
PdfArray tops = destStructTreeRoot.GetKidsObject();
// Now we "walk" through all the elems which belong to the first part, and look for the ones that contain both
// kids from first and second part. We clone found elements and move kids from the second part to cloned elems.
int lastTopBefore = 0;
for (int i_1 = 0; i_1 < tops.Size(); ++i_1)
{
PdfDictionary top = tops.GetAsDictionary(i_1);
if (firstPartElems.Contains(top))
{
lastTopBefore = i_1;
StructureTreeCopier.LastClonedAncestor lastCloned = new StructureTreeCopier.LastClonedAncestor();
lastCloned.ancestor = top;
PdfDictionary topClone = top.Clone(ignoreKeysForClone);
topClone.Put(PdfName.P, destStructTreeRoot.GetPdfObject());
lastCloned.clone = topClone;
SeparateKids(top, firstPartElems, lastCloned);
if (topClone.ContainsKey(PdfName.K))
{
topClone.MakeIndirect(destDocument);
clonedTops.Add(topClone);
}
}
}
for (int i_2 = 0; i_2 < clonedTops.Count; ++i_2)
{
destStructTreeRoot.AddKidObject(lastTopBefore + 1 + i_2, clonedTops[i_2]);
}
CopyTo(destDocument, page2page, callingDocument, false, lastTopBefore + 1);
}
