gecko-dev/editor/libeditor/base/nsEditorUtils.cpp

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 * The Original Code is mozilla.org code.
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#include "nsEditorUtils.h"
#include "nsIDOMDocument.h"
#include "nsIDOMRange.h"
#include "nsIContent.h"
#include "nsLayoutCID.h"
#include "nsIEnumerator.h"
#include "nsISupportsArray.h"


/******************************************************************************
 * nsAutoSelectionReset
 *****************************************************************************/

nsAutoSelectionReset::nsAutoSelectionReset(nsISelection *aSel, nsEditor *aEd) : 
mSel(nsnull)
,mEd(nsnull)
{ 
  if (!aSel || !aEd) return;    // not much we can do, bail.
  if (aEd->ArePreservingSelection()) return;   // we already have initted mSavedSel, so this must be nested call.
  mSel = do_QueryInterface(aSel);
  mEd = aEd;
  if (mSel)
  {
    mEd->PreserveSelectionAcrossActions(mSel);
  }
}

nsAutoSelectionReset::~nsAutoSelectionReset()
{
  if (mSel && mEd->ArePreservingSelection())   // mSel will be null if this was nested call
  {
    mEd->RestorePreservedSelection(mSel);
  }
}

void
nsAutoSelectionReset::Abort()
{
  mEd->StopPreservingSelection();
}


/******************************************************************************
 * some helper classes for iterating the dom tree
 *****************************************************************************/

static NS_DEFINE_IID(kSubtreeIteratorCID, NS_SUBTREEITERATOR_CID);
static NS_DEFINE_IID(kContentIteratorCID, NS_CONTENTITERATOR_CID);

nsDOMIterator::nsDOMIterator() :
mIter(nsnull)
{
}
    
nsDOMIterator::~nsDOMIterator()
{
}
    
nsresult
nsDOMIterator::Init(nsIDOMRange* aRange)
{
  nsresult res = nsComponentManager::CreateInstance(kContentIteratorCID,
                                        nsnull,
                                        NS_GET_IID(nsIContentIterator), 
                                        getter_AddRefs(mIter));
  if (NS_FAILED(res)) return res;
  return mIter->Init(aRange);
}

nsresult
nsDOMIterator::Init(nsIDOMNode* aNode)
{
  nsresult res = nsComponentManager::CreateInstance(kContentIteratorCID,
                                        nsnull,
                                        NS_GET_IID(nsIContentIterator), 
                                        getter_AddRefs(mIter));
  if (NS_FAILED(res)) return res;
  nsCOMPtr<nsIContent> content = do_QueryInterface(aNode);
  return mIter->Init(content);
}

void
nsDOMIterator::ForEach(nsDomIterFunctor& functor) const
{
  nsCOMPtr<nsIContent> content;
  nsCOMPtr<nsIDOMNode> node;
  nsresult res;
  
  // iterate through dom
  while (NS_ENUMERATOR_FALSE == mIter->IsDone())
  {
    res = mIter->CurrentNode(getter_AddRefs(content));
    if (NS_FAILED(res)) return;
    node = do_QueryInterface(content);
    if (!node) return;
    functor(node);
    res = mIter->Next();
    if (NS_FAILED(res)) return;
  }
}

nsresult
nsDOMIterator::MakeList(nsBoolDomIterFunctor& functor,
                        nsCOMArray<nsIDOMNode>& outArrayOfNodes) const
{
  NS_PRECONDITION(outArrayOfNodes.Count() == 0,
                  "Calling MakeList on non-empty list!");
  return AppendList(functor, outArrayOfNodes);
}

nsresult
nsDOMIterator::AppendList(nsBoolDomIterFunctor& functor,
                          nsCOMArray<nsIDOMNode>& arrayOfNodes) const
{
  nsCOMPtr<nsIContent> content;
  nsCOMPtr<nsIDOMNode> node;
  nsresult res;
  
  // iterate through dom and build list
  while (NS_ENUMERATOR_FALSE == mIter->IsDone())
  {
    res = mIter->CurrentNode(getter_AddRefs(content));
    if (NS_FAILED(res)) return res;
    node = do_QueryInterface(content);
    if (!node) return NS_ERROR_NULL_POINTER;
    if (functor(node))
    {
      arrayOfNodes.AppendObject(node);
    }
    res = mIter->Next();
    if (NS_FAILED(res)) return res;
  }
  return NS_OK;
}

nsDOMSubtreeIterator::nsDOMSubtreeIterator()
{
}
    
nsDOMSubtreeIterator::~nsDOMSubtreeIterator()
{
}
    
nsresult
nsDOMSubtreeIterator::Init(nsIDOMRange* aRange)
{
  nsresult res = nsComponentManager::CreateInstance(kSubtreeIteratorCID,
                                        nsnull,
                                        NS_GET_IID(nsIContentIterator), 
                                        getter_AddRefs(mIter));
  if (NS_FAILED(res)) return res;
  return mIter->Init(aRange);
}

nsresult
nsDOMSubtreeIterator::Init(nsIDOMNode* aNode)
{
  nsresult res = nsComponentManager::CreateInstance(kSubtreeIteratorCID,
                                        nsnull,
                                        NS_GET_IID(nsIContentIterator), 
                                        getter_AddRefs(mIter));
  if (NS_FAILED(res)) return res;
  nsCOMPtr<nsIContent> content = do_QueryInterface(aNode);
  return mIter->Init(content);
}

/******************************************************************************
 * some general purpose editor utils
 *****************************************************************************/

PRBool 
nsEditorUtils::IsDescendantOf(nsIDOMNode *aNode, nsIDOMNode *aParent, PRInt32 *aOffset) 
{
  if (!aNode && !aParent) return PR_FALSE;
  if (aNode == aParent) return PR_FALSE;
  
  nsCOMPtr<nsIDOMNode> parent, node = do_QueryInterface(aNode);
  nsresult res;
  
  do
  {
    res = node->GetParentNode(getter_AddRefs(parent));
    if (NS_FAILED(res)) return PR_FALSE;
    if (parent.get() == aParent) 
    {
      if (aOffset)
      {
        nsCOMPtr<nsIContent> pCon(do_QueryInterface(parent));
        nsCOMPtr<nsIContent> cCon(do_QueryInterface(node));
        if (pCon && cCon)
        {
          pCon->IndexOf(cCon, *aOffset);
        }
      }
      return PR_TRUE;
    }
    node = parent;
  } while (parent);
  
  return PR_FALSE;
}

PRBool
nsEditorUtils::IsLeafNode(nsIDOMNode *aNode)
{
  if (!aNode) return PR_FALSE;
  PRBool hasChildren = PR_FALSE;
  aNode->HasChildNodes(&hasChildren);
  return !hasChildren;
}