text: /* -*- 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/. */
  
  //
  // Eric Vaughan
  // Netscape Communications
  //
  // See documentation in associated header file
  //
  
  #include "nsGridRowLayout.h"
  #include "nsBoxLayoutState.h"
  #include "nsIScrollableFrame.h"
  #include "nsBox.h"
  #include "nsStackLayout.h"
  #include "nsGrid.h"
  
  nsGridRowLayout::nsGridRowLayout():nsSprocketLayout()
  {
  }
  
  void
  nsGridRowLayout::ChildrenInserted(nsIFrame* aBox, nsBoxLayoutState& aState,
                                    nsIFrame* aPrevBox,
                                    const nsFrameList::Slice& aNewChildren)
  {
    ChildAddedOrRemoved(aBox, aState);
  }
  
  void
  nsGridRowLayout::ChildrenAppended(nsIFrame* aBox, nsBoxLayoutState& aState,
                                    const nsFrameList::Slice& aNewChildren)
  {
    ChildAddedOrRemoved(aBox, aState);
  }
  
  void
  nsGridRowLayout::ChildrenRemoved(nsIFrame* aBox, nsBoxLayoutState& aState, nsIFrame* aChildList)
  {
    ChildAddedOrRemoved(aBox, aState);
  }
  
  void
  nsGridRowLayout::ChildrenSet(nsIFrame* aBox, nsBoxLayoutState& aState, nsIFrame* aChildList)
  {
    ChildAddedOrRemoved(aBox, aState);
  }
  
  nsIGridPart*
  nsGridRowLayout::GetParentGridPart(nsIFrame* aBox, nsIFrame** aParentBox)
  {
    // go up and find our parent gridRow. Skip and non gridRow
    // parents.
    *aParentBox = nullptr;
    
    // walk up through any scrollboxes
    aBox = nsGrid::GetScrollBox(aBox);
  
    // get the parent
    if (aBox)
      aBox = aBox->GetParentBox();
  
    if (aBox)
    {
      nsIGridPart* parentGridRow = nsGrid::GetPartFromBox(aBox);
      if (parentGridRow && parentGridRow->CanContain(this)) {
        *aParentBox = aBox;
        return parentGridRow;
      }
    }
  
    return nullptr;
  }
  
  
  nsGrid*
  nsGridRowLayout::GetGrid(nsIFrame* aBox, int32_t* aIndex, nsGridRowLayout* aRequestor)
  {
  
     if (aRequestor == nullptr)
     {
        nsIFrame* parentBox; // nsIFrame is implemented by nsIFrame and is not refcounted.
        nsIGridPart* parent = GetParentGridPart(aBox, &parentBox);
        if (parent)
           return parent->GetGrid(parentBox, aIndex, this);
        return nullptr;
     }
  
     int32_t index = -1;
     nsIFrame* child = aBox->GetChildBox();
     int32_t count = 0;
     while(child)
     {
       // if there is a scrollframe walk inside it to its child
       nsIFrame* childBox = nsGrid::GetScrolledBox(child);
  
       nsBoxLayout* layout = childBox->GetLayoutManager();
       nsIGridPart* gridRow = nsGrid::GetPartFromBox(childBox);
       if (gridRow) 
       {
         if (layout == aRequestor) {
            index = count;
            break;
         }
         count += gridRow->GetRowCount();
       } else 
         count++;
  
       child = child->GetNextBox();
     }
  
     // if we didn't find ourselves then the tree isn't properly formed yet
     // this could happen during initial construction so lets just
     // fail.
     if (index == -1) {
       *aIndex = -1;
       return nullptr;
     }
  
     (*aIndex) += index;
  
     nsIFrame* parentBox; // nsIFrame is implemented by nsIFrame and is not refcounted.
     nsIGridPart* parent = GetParentGridPart(aBox, &parentBox);
     if (parent)
       return parent->GetGrid(parentBox, aIndex, this);
  
     return nullptr;
  }
  
  nsMargin
  nsGridRowLayout::GetTotalMargin(nsIFrame* aBox, bool aIsHorizontal)
  {
    // get our parents margin
    nsMargin margin(0,0,0,0);
    nsIFrame* parent = nullptr;
    nsIGridPart* part = GetParentGridPart(aBox, &parent);
    if (part && parent) {
      // if we are the first or last child walk upward and add margins.
  
      // make sure we check for a scrollbox
      aBox = nsGrid::GetScrollBox(aBox);
  
      // see if we have a next to see if we are last
      nsIFrame* next = aBox->GetNextBox();
  
      // get the parent first child to see if we are first
      nsIFrame* child = parent->GetChildBox();
  
      margin = part->GetTotalMargin(parent, aIsHorizontal);
  
      // if first or last
      if (child == aBox || next == nullptr) {
  
         // if it's not the first child remove the top margin
         // we don't need it.
         if (child != aBox)
         {
            if (aIsHorizontal)
                margin.top = 0;
            else 
                margin.left = 0;
         }
  
         // if it's not the last child remove the bottom margin
         // we don't need it.
         if (next != nullptr)
         {
            if (aIsHorizontal)
                margin.bottom = 0;
            else 
                margin.right = 0;
         }
  
      }
    }
      
    // add ours to it.
    nsMargin ourMargin;
    aBox->GetMargin(ourMargin);
    margin += ourMargin;
  
    return margin;
  }
  
  NS_IMPL_ADDREF_INHERITED(nsGridRowLayout, nsBoxLayout)
  NS_IMPL_RELEASE_INHERITED(nsGridRowLayout, nsBoxLayout)
  
  NS_INTERFACE_MAP_BEGIN(nsGridRowLayout)
    NS_INTERFACE_MAP_ENTRY(nsIGridPart)
    NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIGridPart)
  NS_INTERFACE_MAP_END_INHERITING(nsBoxLayout)
  