/*
 * The contents of this file are subject to the Mozilla Public
 * License Version 1.1 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code is Mozilla MathML Project.
 *
 * The Initial Developer of the Original Code is The University Of
 * Queensland.  Portions created by The University Of Queensland are
 * Copyright (C) 1999 The University Of Queensland.  All Rights Reserved.
 *
 * Contributor(s):
 *   Roger B. Sidje <rbs@maths.uq.edu.au>
 */


#include "nsCOMPtr.h"
#include "nsHTMLParts.h"
#include "nsIHTMLContent.h"
#include "nsFrame.h"
#include "nsLineLayout.h"
#include "nsHTMLIIDs.h"
#include "nsIPresContext.h"
#include "nsHTMLAtoms.h"
#include "nsUnitConversion.h"
#include "nsIStyleContext.h"
#include "nsStyleConsts.h"
#include "nsINameSpaceManager.h"
#include "nsIRenderingContext.h"
#include "nsIFontMetrics.h"
#include "nsStyleUtil.h"

#include "nsIDOMText.h"

#include "nsMathMLmsFrame.h"

//
// <ms> -- string literal - implementation
//

nsresult
NS_NewMathMLmsFrame(nsIPresShell* aPresShell, nsIFrame** aNewFrame)
{
  NS_PRECONDITION(aNewFrame, "null OUT ptr");
  if (nsnull == aNewFrame) {
    return NS_ERROR_NULL_POINTER;
  }
  nsMathMLmsFrame* it = new (aPresShell) nsMathMLmsFrame;
  if (nsnull == it) {
    return NS_ERROR_OUT_OF_MEMORY;
  }
  *aNewFrame = it;
  return NS_OK;
}

nsMathMLmsFrame::nsMathMLmsFrame()
{
}

nsMathMLmsFrame::~nsMathMLmsFrame()
{
}


NS_IMETHODIMP
nsMathMLmsFrame::SetInitialChildList(nsIPresContext* aPresContext,
                                     nsIAtom*        aListName,
                                     nsIFrame*       aChildList)
{
  // It is assumed that the mathml.css file contains two rules:
  // ms:before { content: open-quote; }
  // ms:after { content: close-quote; }
  // With these two rules, the frame construction code will
  // create inline frames that contain text frames which themselves
  // contain the text content of the quotes.
  // So the main idea in this code is to see if there are lquote and 
  // rquote attributes. If these are there, we ovewrite the default
  // quotes in the text frames.

  // But what if the mathml.css file wasn't loaded? 
  // We also check that we are not relying on null pointers...

  PRInt32 count = 0;
  nsIFrame* rightFrame = nsnull;
  nsIFrame* leftFrame = nsnull;
  nsIFrame* childFrame = aChildList;
  while (childFrame) {
    if (0 == count) leftFrame = childFrame;
    // 1 == count is the the frame for the actual content of <ms>
    else if (2 == count) rightFrame = childFrame;
    count++;
    childFrame->GetNextSibling(&childFrame);
  }

  if (3 == count && leftFrame && rightFrame) {
    nsAutoString value;
    nsIFrame* textFrame;
    nsCOMPtr<nsIContent> quoteContent;
    // lquote
    if (NS_CONTENT_ATTR_HAS_VALUE == GetAttribute(mContent, mPresentationData.mstyle,
                     nsMathMLAtoms::lquote_, value)) {
      leftFrame->FirstChild(aPresContext, nsnull, &textFrame);
      if (textFrame) {
        textFrame->GetContent(getter_AddRefs(quoteContent));
        if (quoteContent.get()) {
          nsCOMPtr<nsIDOMText> domText(do_QueryInterface(quoteContent));
          if (domText.get()) domText->SetData(value);
        }
      }
    }
    // rquote
    if (NS_CONTENT_ATTR_HAS_VALUE == GetAttribute(mContent, mPresentationData.mstyle,
                     nsMathMLAtoms::rquote_, value)) {
      rightFrame->FirstChild(aPresContext, nsnull, &textFrame);
      if (textFrame) {
        textFrame->GetContent(getter_AddRefs(quoteContent));
        if (quoteContent.get()) {
          nsCOMPtr<nsIDOMText> domText(do_QueryInterface(quoteContent));
          if (domText.get()) domText->SetData(value);
        }
      }
    }
  }

  // let the base class take care of the rest
  return nsMathMLContainerFrame::SetInitialChildList(aPresContext, aListName, aChildList);
}