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 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this

  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

 #include "nsTableFrame.h"

 #include "nsTableRowGroupFrame.h"

 #include "nsTableRowFrame.h"

 #include "nsTableColGroupFrame.h"

 #include "nsTableColFrame.h"

 #include "nsTableCellFrame.h"

 #include "nsTablePainter.h"

 #include "nsCSSRendering.h"

 #include "nsDisplayList.h"

 /* ~*~ Table Background Painting ~*~

    Mozilla's Table Background painting follows CSS2.1:17.5.1

    That section does not, however, describe the effect of

    borders on background image positioning. What we do is:

      - in separate borders, the borders are passed in so that

        their width figures in image positioning, even for rows/cols, which

        don't have visible borders. This is done to allow authors

        to position row backgrounds by, for example, aligning the

        top left corner with the top left padding corner of the

        top left table cell in the row in cases where all cells

        have consistent border widths. If we didn't honor these

        invisible borders, there would be no way to align

        backgrounds with the padding edges, and designs would be

        lost underneath the border.

      - in collapsing borders, because the borders collapse, we

        use the -continuous border- width to synthesize a border

        style and pass that in instead of using the element's

        assigned style directly.

        The continuous border on a given edge of an element is

        the collapse of all borders guaranteed to be continuous

        along that edge. Cell borders are ignored (because, for

        example, setting a thick border on the leftmost cell

        should not shift the row background over; this way a

        striped background set on <tr> will line up across rows

        even if the cells are assigned arbitrary border widths.

        For example, the continuous border on the top edge of a

        row group is the collapse of any row group, row, and

        table borders involved. (The first row group's top would

        be [table-top + row group top + first row top]. It's bottom

        would be [row group bottom + last row bottom + next row

        top + next row group top].)

        The top edge of a column group likewise includes the

        table top, row group top, and first row top borders. However,

        it *also* includes its own top border, since that is guaranteed

        to be continuous. It does not include column borders because

        those are not guaranteed to be continuous: there may be two

        columns with different borders in a single column group.

        An alternative would be to define the continuous border as

          [table? + row group + row] for horizontal

          [table? + col group + col] for vertical

        This makes it easier to line up backgrounds across elements

        despite varying border widths, but it does not give much

        flexibility in aligning /to/ those border widths.

 */

 /* ~*~ TableBackgroundPainter ~*~

    The TableBackgroundPainter is created and destroyed in one painting call.

    Its principal function is PaintTable, which paints all table element

    backgrounds. The initial code in that method sets up an array of column

    data that caches the background styles and the border sizes for the

    columns and colgroups in TableBackgroundData structs in mCols. Data for

    BC borders are calculated and stashed in a synthesized border style struct

    in the data struct since collapsed borders aren't the same width as style-

    assigned borders. The data struct optimizes by only doing this if there's

    an image background; otherwise we don't care. //XXX should also check background-origin

    The class then loops through the row groups, rows, and cells. It uses

    the mRowGroup and mRow TableBackgroundData structs to cache data for

    the current frame in the loop. At the cell level, it paints the backgrounds,

    one over the other, inside the cell rect.

    The exception to this pattern is when a table element creates a (pseudo)

    stacking context. Elements with stacking contexts (e.g., 'opacity' applied)

    are <dfn>passed through</dfn>, which means their data (and their

    descendants' data) are not cached. The full loop is still executed, however,

    so that underlying layers can get painted at the cell level.

    The TableBackgroundPainter is then destroyed.

    Elements with stacking contexts set up their own painter to finish the

    painting process, since they were skipped. They call the appropriate

    sub-part of the loop (e.g. PaintRow) which will paint the frame and

    descendants. Note that it is permissible according to CSS2.1 to ignore'

    'position:relative' (and implicitly, 'opacity') on table parts so that

    table parts can never create stacking contexts; if we want to, we can

    implement that, and then we won't have to deal with TableBackgroundPainter

    being used anywhere but from the nsTableFrame.

    XXX views are going 

  */

 TableBackgroundPainter::TableBackgroundData::TableBackgroundData()

   : mFrame(nullptr),

     mVisible(false),

     mBorder(nullptr),

     mSynthBorder(nullptr)

 {

   MOZ_COUNT_CTOR(TableBackgroundData);

 }

 TableBackgroundPainter::TableBackgroundData::~TableBackgroundData()

 {

   NS_ASSERTION(!mSynthBorder, "must call Destroy before dtor");

   MOZ_COUNT_DTOR(TableBackgroundData);

 }

 void

 TableBackgroundPainter::TableBackgroundData::Destroy(nsPresContext* aPresContext)

 {

   NS_PRECONDITION(aPresContext, "null prescontext");

   if (mSynthBorder) {

     mSynthBorder->Destroy(aPresContext);

     mSynthBorder = nullptr;

   }

 }

 void

 TableBackgroundPainter::TableBackgroundData::Clear()

 {

   mRect.SetEmpty();

   mFrame = nullptr;

   mBorder = nullptr;

   mVisible = false;

 }

 void

 TableBackgroundPainter::TableBackgroundData::SetFrame(nsIFrame* aFrame)

 {

   NS_PRECONDITION(aFrame, "null frame");

   mFrame = aFrame;

   mRect = aFrame->GetRect();

 }

 void

 TableBackgroundPainter::TableBackgroundData::SetData()

 {

   NS_PRECONDITION(mFrame, "null frame");

   if (mFrame->IsVisibleForPainting()) {

     mVisible = true;

     mBorder = mFrame->StyleBorder();

   }

 }

 void

 TableBackgroundPainter::TableBackgroundData::SetFull(nsIFrame* aFrame)

 {

   NS_PRECONDITION(aFrame, "null frame");

   SetFrame(aFrame);

   SetData();

 }

 inline bool

 TableBackgroundPainter::TableBackgroundData::ShouldSetBCBorder()

 {

   /* we only need accurate border data when positioning background images*/

   if (!mVisible) {

     return false;

   }

   const nsStyleBackground *bg = mFrame->StyleBackground();

   NS_FOR_VISIBLE_BACKGROUND_LAYERS_BACK_TO_FRONT(i, bg) {

     if (!bg->mLayers[i].mImage.IsEmpty())

       return true;

   }

   return false;

 }

 nsresult

 TableBackgroundPainter::TableBackgroundData::SetBCBorder(nsMargin& aBorder,

                                                          TableBackgroundPainter* aPainter)

 {

   NS_PRECONDITION(aPainter, "null painter");

   if (!mSynthBorder) {

     mSynthBorder = new (aPainter->mPresContext)

                         nsStyleBorder(aPainter->mZeroBorder);

     if (!mSynthBorder) return NS_ERROR_OUT_OF_MEMORY;

   }

   NS_FOR_CSS_SIDES(side) {

     mSynthBorder->SetBorderWidth(side, aBorder.Side(side));

   }

   mBorder = mSynthBorder;

   return NS_OK;

 }

 TableBackgroundPainter::TableBackgroundPainter(nsTableFrame*        aTableFrame,

                                                Origin               aOrigin,

                                                nsPresContext*       aPresContext,

                                                nsRenderingContext& aRenderingContext,

                                                const nsRect&        aDirtyRect,

                                                const nsPoint&       aRenderPt,

                                                uint32_t             aBGPaintFlags)

   : mPresContext(aPresContext),

     mRenderingContext(aRenderingContext),

     mRenderPt(aRenderPt),

     mDirtyRect(aDirtyRect),

     mOrigin(aOrigin),

     mCols(nullptr),

     mZeroBorder(aPresContext),

     mBGPaintFlags(aBGPaintFlags)

 {

   MOZ_COUNT_CTOR(TableBackgroundPainter);

   NS_FOR_CSS_SIDES(side) {

     mZeroBorder.SetBorderStyle(side, NS_STYLE_BORDER_STYLE_SOLID);

     mZeroBorder.SetBorderWidth(side, 0);

   }

   mIsBorderCollapse = aTableFrame->IsBorderCollapse();

 #ifdef DEBUG

   mCompatMode = mPresContext->CompatibilityMode();

 #endif

   mNumCols = aTableFrame->GetColCount();

 }

 TableBackgroundPainter::~TableBackgroundPainter()

 {

   if (mCols) {

     TableBackgroundData* lastColGroup = nullptr;

     for (uint32_t i = 0; i < mNumCols; i++) {

       if (mCols[i].mColGroup != lastColGroup) {

         lastColGroup = mCols[i].mColGroup;

         NS_ASSERTION(mCols[i].mColGroup, "colgroup data should not be null - bug 237421");

         // we need to wallpaper a over zero pointer deref, bug 237421 will have the real fix

         if(lastColGroup)

           lastColGroup->Destroy(mPresContext);

         delete lastColGroup;

       }

       mCols[i].mColGroup = nullptr;

       mCols[i].mCol.Destroy(mPresContext);

     }

     delete [] mCols;

   }

   mRowGroup.Destroy(mPresContext);

   mRow.Destroy(mPresContext);

   MOZ_COUNT_DTOR(TableBackgroundPainter);

 }

 nsresult

 TableBackgroundPainter::PaintTableFrame(nsTableFrame*         aTableFrame,

                                         nsTableRowGroupFrame* aFirstRowGroup,

                                         nsTableRowGroupFrame* aLastRowGroup,

                                         const nsMargin&       aDeflate)

 {

   NS_PRECONDITION(aTableFrame, "null frame");

   TableBackgroundData tableData;

   tableData.SetFull(aTableFrame);

   tableData.mRect.MoveTo(0,0); //using table's coords

   tableData.mRect.Deflate(aDeflate);

   if (mIsBorderCollapse && tableData.ShouldSetBCBorder()) {

     if (aFirstRowGroup && aLastRowGroup && mNumCols > 0) {

       //only handle non-degenerate tables; we need a more robust BC model

       //to make degenerate tables' borders reasonable to deal with

       nsMargin border, tempBorder;

       nsTableColFrame* colFrame = aTableFrame->GetColFrame(mNumCols - 1);

       if (colFrame) {

         colFrame->GetContinuousBCBorderWidth(tempBorder);

       }

       border.right = tempBorder.right;

       aLastRowGroup->GetContinuousBCBorderWidth(tempBorder);

       border.bottom = tempBorder.bottom;

       nsTableRowFrame* rowFrame = aFirstRowGroup->GetFirstRow();

       if (rowFrame) {

         rowFrame->GetContinuousBCBorderWidth(tempBorder);

         border.top = tempBorder.top;

       }

       border.left = aTableFrame->GetContinuousLeftBCBorderWidth();

       nsresult rv = tableData.SetBCBorder(border, this);

       if (NS_FAILED(rv)) {

         tableData.Destroy(mPresContext);

         return rv;

       }

     }

   }

   if (tableData.IsVisible()) {

     nsCSSRendering::PaintBackgroundWithSC(mPresContext, mRenderingContext,

                                           tableData.mFrame, mDirtyRect,

                                           tableData.mRect + mRenderPt,

                                           tableData.mFrame->StyleContext(),

                                           *tableData.mBorder,

                                           mBGPaintFlags);

   }

   tableData.Destroy(mPresContext);

   return NS_OK;

 }

 void

 TableBackgroundPainter::TranslateContext(nscoord aDX,

                                          nscoord aDY)

 {

   mRenderPt += nsPoint(aDX, aDY);

   if (mCols) {

     TableBackgroundData* lastColGroup = nullptr;

     for (uint32_t i = 0; i < mNumCols; i++) {

       mCols[i].mCol.mRect.MoveBy(-aDX, -aDY);

       if (lastColGroup != mCols[i].mColGroup) {

         NS_ASSERTION(mCols[i].mColGroup, "colgroup data should not be null - bug 237421");

         // we need to wallpaper a over zero pointer deref, bug 237421 will have the real fix

         if (!mCols[i].mColGroup)

           return;

         mCols[i].mColGroup->mRect.MoveBy(-aDX, -aDY);

         lastColGroup = mCols[i].mColGroup;

       }

     }

   }

 }

 nsresult

 TableBackgroundPainter::PaintTable(nsTableFrame*   aTableFrame,

                                    const nsMargin& aDeflate,

                                    bool            aPaintTableBackground)

 {

   NS_PRECONDITION(aTableFrame, "null table frame");

   nsTableFrame::RowGroupArray rowGroups;

   aTableFrame->OrderRowGroups(rowGroups);

   if (rowGroups.Length() < 1) { //degenerate case

     if (aPaintTableBackground) {

       PaintTableFrame(aTableFrame, nullptr, nullptr, nsMargin(0,0,0,0));

     }

     /* No cells; nothing else to paint */

     return NS_OK;

   }

   if (aPaintTableBackground) {

     PaintTableFrame(aTableFrame, rowGroups[0], rowGroups[rowGroups.Length() - 1],

                     aDeflate);

   }

   /*Set up column background/border data*/

   if (mNumCols > 0) {

     nsFrameList& colGroupList = aTableFrame->GetColGroups();

     NS_ASSERTION(colGroupList.FirstChild(), "table should have at least one colgroup");

     mCols = new ColData[mNumCols];

     if (!mCols) return NS_ERROR_OUT_OF_MEMORY;

     TableBackgroundData* cgData = nullptr;

     nsMargin border;

     /* BC left borders aren't stored on cols, but the previous column's

        right border is the next one's left border.*/

     //Start with table's left border.

     nscoord lastLeftBorder = aTableFrame->GetContinuousLeftBCBorderWidth();

     for (nsTableColGroupFrame* cgFrame = static_cast<nsTableColGroupFrame*>(colGroupList.FirstChild());

          cgFrame; cgFrame = static_cast<nsTableColGroupFrame*>(cgFrame->GetNextSibling())) {

       if (cgFrame->GetColCount() < 1) {

         //No columns, no cells, so no need for data

         continue;

       }

       /*Create data struct for column group*/

       cgData = new TableBackgroundData;

       if (!cgData) return NS_ERROR_OUT_OF_MEMORY;

       cgData->SetFull(cgFrame);

       if (mIsBorderCollapse && cgData->ShouldSetBCBorder()) {

         border.left = lastLeftBorder;

         cgFrame->GetContinuousBCBorderWidth(border);

         nsresult rv = cgData->SetBCBorder(border, this);

         if (NS_FAILED(rv)) {

           cgData->Destroy(mPresContext);

           delete cgData;

           return rv;

         }

       }

       // Boolean that indicates whether mCols took ownership of cgData

       bool cgDataOwnershipTaken = false;

       /*Loop over columns in this colgroup*/

       for (nsTableColFrame* col = cgFrame->GetFirstColumn(); col;

            col = static_cast<nsTableColFrame*>(col->GetNextSibling())) {

         /*Create data struct for column*/

         uint32_t colIndex = col->GetColIndex();

         NS_ASSERTION(colIndex < mNumCols, "prevent array boundary violation");

         if (mNumCols <= colIndex)

           break;

         mCols[colIndex].mCol.SetFull(col);

         //Bring column mRect into table's coord system

         mCols[colIndex].mCol.mRect.MoveBy(cgData->mRect.x, cgData->mRect.y);

         //link to parent colgroup's data

         mCols[colIndex].mColGroup = cgData;

         cgDataOwnershipTaken = true;

         if (mIsBorderCollapse) {

           border.left = lastLeftBorder;

           lastLeftBorder = col->GetContinuousBCBorderWidth(border);

           if (mCols[colIndex].mCol.ShouldSetBCBorder()) {

             nsresult rv = mCols[colIndex].mCol.SetBCBorder(border, this);

             if (NS_FAILED(rv)) return rv;

           }

         }

       }

       if (!cgDataOwnershipTaken) {

         cgData->Destroy(mPresContext);

         delete cgData;

       }

     }

   }

   for (uint32_t i = 0; i < rowGroups.Length(); i++) {

     nsTableRowGroupFrame* rg = rowGroups[i];

     mRowGroup.SetFrame(rg);

     // Need to compute the right rect via GetOffsetTo, since the row

     // group may not be a child of the table.

     mRowGroup.mRect.MoveTo(rg->GetOffsetTo(aTableFrame));

     if (mRowGroup.mRect.Intersects(mDirtyRect - mRenderPt)) {

       nsresult rv = PaintRowGroup(rg, rg->IsPseudoStackingContextFromStyle());

       if (NS_FAILED(rv)) return rv;

     }

   }

   return NS_OK;

 }

 nsresult

 TableBackgroundPainter::PaintRowGroup(nsTableRowGroupFrame* aFrame,

                                       bool                  aPassThrough)

 {

   NS_PRECONDITION(aFrame, "null frame");

   if (!mRowGroup.mFrame) {

     mRowGroup.SetFrame(aFrame);

   }

   nsTableRowFrame* firstRow = aFrame->GetFirstRow();

   /* Load row group data */

   if (!aPassThrough) {

     mRowGroup.SetData();

     if (mIsBorderCollapse && mRowGroup.ShouldSetBCBorder()) {

       nsMargin border;

       if (firstRow) {

         //pick up first row's top border (= rg top border)

         firstRow->GetContinuousBCBorderWidth(border);

         /* (row group doesn't store its top border) */

       }

       //overwrite sides+bottom borders with rg's own

       aFrame->GetContinuousBCBorderWidth(border);

       nsresult res = mRowGroup.SetBCBorder(border, this);

       if (!NS_SUCCEEDED(res)) {

         return res;

       }

     }

     aPassThrough = !mRowGroup.IsVisible();

   }

   /* translate everything into row group coord system*/

   if (eOrigin_TableRowGroup != mOrigin) {

     TranslateContext(mRowGroup.mRect.x, mRowGroup.mRect.y);

   }

   nsRect rgRect = mRowGroup.mRect;

   mRowGroup.mRect.MoveTo(0, 0);

   /* Find the right row to start with */

   nscoord ignored; // We don't care about overflow above, since what we really

                    // care about are backgrounds and overflow above doesn't

                    // correspond to backgrounds, since cells can't span up from

                    // their originating row.  We do care about overflow below,

                    // however, since that can be due to rowspans.

   // Note that mDirtyRect  - mRenderPt is guaranteed to be in the row

   // group's coordinate system here, so passing its .y to

   // GetFirstRowContaining is ok.

   nsIFrame* cursor = aFrame->GetFirstRowContaining(mDirtyRect.y - mRenderPt.y, &ignored);

   // Sadly, it seems like there may be non-row frames in there... or something?

   // There are certainly null-checks in GetFirstRow() and GetNextRow().  :(

   while (cursor && cursor->GetType() != nsGkAtoms::tableRowFrame) {

     cursor = cursor->GetNextSibling();

   }

   // It's OK if cursor is null here.

   nsTableRowFrame* row = static_cast<nsTableRowFrame*>(cursor);  

   if (!row) {

     // No useful cursor; just start at the top.  Don't bother to set up a

     // cursor; if we've gotten this far then we've already built the display

     // list for the rowgroup, so not having a cursor means that there's some

     // good reason we don't have a cursor and we shouldn't create one here.

     row = firstRow;

   }

   /* Finally paint */

   for (; row; row = row->GetNextRow()) {

     mRow.SetFrame(row);

     if (mDirtyRect.YMost() - mRenderPt.y < mRow.mRect.y) { // Intersect wouldn't handle

                                              // rowspans.

       // All done; cells originating in later rows can't intersect mDirtyRect.

       break;

     }

     nsresult rv = PaintRow(row, aPassThrough || row->IsPseudoStackingContextFromStyle());

     if (NS_FAILED(rv)) return rv;

   }

   /* translate back into table coord system */

   if (eOrigin_TableRowGroup != mOrigin) {

     TranslateContext(-rgRect.x, -rgRect.y);

   }

   /* unload rg data */

   mRowGroup.Clear();

   return NS_OK;

 }

 nsresult

 TableBackgroundPainter::PaintRow(nsTableRowFrame* aFrame,

                                  bool             aPassThrough)

 {

   NS_PRECONDITION(aFrame, "null frame");

   if (!mRow.mFrame) {

     mRow.SetFrame(aFrame);

   }

   /* Load row data */

   if (!aPassThrough) {

     mRow.SetData();

     if (mIsBorderCollapse && mRow.ShouldSetBCBorder()) {

       nsMargin border;

       nsTableRowFrame* nextRow = aFrame->GetNextRow();

       if (nextRow) { //outer top below us is inner bottom for us

         border.bottom = nextRow->GetOuterTopContBCBorderWidth();

       }

       else { //acquire rg's bottom border

         nsTableRowGroupFrame* rowGroup = static_cast<nsTableRowGroupFrame*>(aFrame->GetParent());

         rowGroup->GetContinuousBCBorderWidth(border);

       }

       //get the rest of the borders; will overwrite all but bottom

       aFrame->GetContinuousBCBorderWidth(border);

       nsresult res = mRow.SetBCBorder(border, this);

       if (!NS_SUCCEEDED(res)) {

         return res;

       }

     }

     aPassThrough = !mRow.IsVisible();

   }

   /* Translate */

   if (eOrigin_TableRow == mOrigin) {

     /* If we originate from the row, then make the row the origin. */

     mRow.mRect.MoveTo(0, 0);

   }

   //else: Use row group's coord system -> no translation necessary

   for (nsTableCellFrame* cell = aFrame->GetFirstCell(); cell; cell = cell->GetNextCell()) {

     //Translate to use the same coord system as mRow.

     mCellRect = cell->GetRect() + mRow.mRect.TopLeft() + mRenderPt;

     if (mCellRect.Intersects(mDirtyRect)) {

       nsresult rv = PaintCell(cell, aPassThrough || cell->IsPseudoStackingContextFromStyle());

       if (NS_FAILED(rv)) return rv;

     }

   }

   /* Unload row data */

   mRow.Clear();

   return NS_OK;

 }

 nsresult

 TableBackgroundPainter::PaintCell(nsTableCellFrame* aCell,

                                   bool aPassSelf)

 {

   NS_PRECONDITION(aCell, "null frame");

   const nsStyleTableBorder* cellTableStyle;

   cellTableStyle = aCell->StyleTableBorder();

   if (!(NS_STYLE_TABLE_EMPTY_CELLS_SHOW == cellTableStyle->mEmptyCells ||

         NS_STYLE_TABLE_EMPTY_CELLS_SHOW_BACKGROUND == cellTableStyle->mEmptyCells)

       && aCell->GetContentEmpty() && !mIsBorderCollapse) {

     return NS_OK;

   }

   int32_t colIndex;

   aCell->GetColIndex(colIndex);

   NS_ASSERTION(colIndex < int32_t(mNumCols), "prevent array boundary violation");

   if (int32_t(mNumCols) <= colIndex)

     return NS_OK;

   //Paint column group background

   if (mCols && mCols[colIndex].mColGroup && mCols[colIndex].mColGroup->IsVisible()) {

     nsCSSRendering::PaintBackgroundWithSC(mPresContext, mRenderingContext,

                                           mCols[colIndex].mColGroup->mFrame, mDirtyRect,

                                           mCols[colIndex].mColGroup->mRect + mRenderPt,

                                           mCols[colIndex].mColGroup->mFrame->StyleContext(),

                                           *mCols[colIndex].mColGroup->mBorder,

                                           mBGPaintFlags, &mCellRect);

   }

   //Paint column background

   if (mCols && mCols[colIndex].mCol.IsVisible()) {

     nsCSSRendering::PaintBackgroundWithSC(mPresContext, mRenderingContext,

                                           mCols[colIndex].mCol.mFrame, mDirtyRect,

                                           mCols[colIndex].mCol.mRect + mRenderPt,

                                           mCols[colIndex].mCol.mFrame->StyleContext(),

                                           *mCols[colIndex].mCol.mBorder,

                                           mBGPaintFlags, &mCellRect);

   }

   //Paint row group background

   if (mRowGroup.IsVisible()) {

     nsCSSRendering::PaintBackgroundWithSC(mPresContext, mRenderingContext,

                                           mRowGroup.mFrame, mDirtyRect,

                                           mRowGroup.mRect + mRenderPt,

                                           mRowGroup.mFrame->StyleContext(),

                                           *mRowGroup.mBorder,

                                           mBGPaintFlags, &mCellRect);

   }

   //Paint row background

   if (mRow.IsVisible()) {

     nsCSSRendering::PaintBackgroundWithSC(mPresContext, mRenderingContext,

                                           mRow.mFrame, mDirtyRect,

                                           mRow.mRect + mRenderPt,

                                           mRow.mFrame->StyleContext(),

                                           *mRow.mBorder,

                                           mBGPaintFlags, &mCellRect);

   }

   //Paint cell background in border-collapse unless we're just passing

   if (mIsBorderCollapse && !aPassSelf) {

     aCell->PaintCellBackground(mRenderingContext, mDirtyRect,

                                mCellRect.TopLeft(), mBGPaintFlags);

   }

   return NS_OK;

 }