gecko-dev/layout/generic/nsHTMLContainerFrame.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * The contents of this file are subject to the Netscape Public License
 * Version 1.0 (the "NPL"); you may not use this file except in
 * compliance with the NPL.  You may obtain a copy of the NPL at
 * http://www.mozilla.org/NPL/
 *
 * Software distributed under the NPL is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
 * for the specific language governing rights and limitations under the
 * NPL.
 *
 * The Initial Developer of this code under the NPL is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
 * Reserved.
 */
#include "nsHTMLContainerFrame.h"
#include "nsIRenderingContext.h"
#include "nsIPresContext.h"
#include "nsIPresShell.h"
#include "nsIStyleContext.h"
#include "nsStyleConsts.h"
#include "nsCSSRendering.h"
#include "nsIContent.h"
#include "nsHTMLAtoms.h"
#include "nsIWidget.h"
#include "nsILinkHandler.h"
#include "nsHTMLValue.h"
#include "nsGUIEvent.h"
#include "nsIDocument.h"
#include "nsIURL.h"
#include "nsIPtr.h"
#include "nsAbsoluteFrame.h"
#include "nsPlaceholderFrame.h"
#include "nsIContentDelegate.h"
#include "nsIHTMLContent.h"
#include "nsHTMLParts.h"
#include "nsHTMLBase.h"
#include "nsScrollFrame.h"
#include "nsIView.h"
#include "nsIReflowCommand.h"

NS_DEF_PTR(nsIStyleContext);

nsHTMLContainerFrame::nsHTMLContainerFrame(nsIContent* aContent, nsIFrame* aParent)
  : nsContainerFrame(aContent, aParent)
{
}

nsHTMLContainerFrame::~nsHTMLContainerFrame()
{
}

NS_METHOD nsHTMLContainerFrame::Paint(nsIPresContext& aPresContext,
                                      nsIRenderingContext& aRenderingContext,
                                      const nsRect& aDirtyRect)
{
  // Paint our background and border
  const nsStyleDisplay* disp =
    (const nsStyleDisplay*)mStyleContext->GetStyleData(eStyleStruct_Display);

  if (disp->mVisible && mRect.width && mRect.height) {
    PRIntn skipSides = GetSkipSides();
    const nsStyleColor* color =
      (const nsStyleColor*)mStyleContext->GetStyleData(eStyleStruct_Color);
    const nsStyleSpacing* spacing =
      (const nsStyleSpacing*)mStyleContext->GetStyleData(eStyleStruct_Spacing);

    nsRect  rect(0, 0, mRect.width, mRect.height);
    nsCSSRendering::PaintBackground(aPresContext, aRenderingContext, this,
                                    aDirtyRect, rect, *color);
    nsCSSRendering::PaintBorder(aPresContext, aRenderingContext, this,
                                aDirtyRect, rect, *spacing, skipSides);
  }

  PaintChildren(aPresContext, aRenderingContext, aDirtyRect);

  if (nsIFrame::GetShowFrameBorders()) {
    nsIView* view;
    GetView(view);
    if (nsnull != view) {
      aRenderingContext.SetColor(NS_RGB(0,0,255));
    }
    else {
      aRenderingContext.SetColor(NS_RGB(255,0,0));
    }
    aRenderingContext.DrawRect(0, 0, mRect.width, mRect.height);
  }
  return NS_OK;
}

NS_METHOD nsHTMLContainerFrame::HandleEvent(nsIPresContext& aPresContext,
                                            nsGUIEvent* aEvent,
                                            nsEventStatus& aEventStatus)
{
  return nsContainerFrame::HandleEvent(aPresContext, aEvent, aEventStatus);
}

NS_METHOD nsHTMLContainerFrame::GetCursorAndContentAt(nsIPresContext& aPresContext,
                                            const nsPoint& aPoint,
                                            nsIFrame** aFrame,
                                            nsIContent** aContent,
                                            PRInt32& aCursor)
{
  // Set content here, child will override if found.
  *aContent = mContent;
  
  // Get my cursor
  const nsStyleColor* styleColor = (const nsStyleColor*)
    mStyleContext->GetStyleData(eStyleStruct_Color);
  PRInt32 myCursor = styleColor->mCursor;

  // Get child's cursor, if any
  nsContainerFrame::GetCursorAndContentAt(aPresContext, aPoint, aFrame, aContent, aCursor);
  if (aCursor != NS_STYLE_CURSOR_INHERIT) {
    nsIAtom* tag = mContent->GetTag();
    if (nsHTMLAtoms::a == tag) {
      // Anchor tags override their child cursors in some cases.
      if ((NS_STYLE_CURSOR_IBEAM == aCursor) &&
          (NS_STYLE_CURSOR_INHERIT != myCursor)) {
        aCursor = myCursor;
      }
    }
    NS_RELEASE(tag);
    return NS_OK;
  }

  if (NS_STYLE_CURSOR_INHERIT != myCursor) {
    // If this container has a particular cursor, use it, otherwise
    // let the child decide.
    *aFrame = this;
    aCursor = myCursor;
    return NS_OK;
  }

  // No specific cursor for us
  aCursor = NS_STYLE_CURSOR_INHERIT;
  return NS_OK;
}

NS_METHOD nsHTMLContainerFrame::ContentAppended(nsIPresShell*   aShell,
                                                nsIPresContext* aPresContext,
                                                nsIContent*     aContainer)
{
  // Get the last-in-flow
  nsHTMLContainerFrame* lastInFlow = (nsHTMLContainerFrame*)GetLastInFlow();

  // Generate a reflow command for the frame
  nsIReflowCommand* cmd;
  nsresult          result;
                                                  
  result = NS_NewHTMLReflowCommand(&cmd, lastInFlow, nsIReflowCommand::FrameAppended);
  if (NS_OK == result) {
    aShell->AppendReflowCommand(cmd);
    NS_RELEASE(cmd);
  }
  
  return NS_OK;
}

NS_IMETHODIMP
nsHTMLContainerFrame::ContentInserted(nsIPresShell*   aShell,
                                      nsIPresContext* aPresContext,
                                      nsIContent*     aContainer,
                                      nsIContent*     aChild,
                                      PRInt32         aIndexInParent)
{
  NS_ASSERTION(!IsPseudoFrame(), "pseudos not supported here");

  // Find the frame that precedes the insertion point
  nsIFrame* prevSibling = nsnull;
  if (aIndexInParent > 0) {
    nsIContent* precedingContent = aContainer->ChildAt(aIndexInParent - 1);
    prevSibling = aShell->FindFrameWithContent(precedingContent);
    NS_RELEASE(precedingContent);

    // The frame may have a next-in-flow. Get the last-in-flow
    nsIFrame* nextInFlow;
    do {
      prevSibling->GetNextInFlow(nextInFlow);
      if (nsnull != nextInFlow) {
        prevSibling = nextInFlow;
      }
    } while (nsnull != nextInFlow);
  }

  // Get the geometric parent for the prevSibling. We expect it to be
  // this frame or one of its next-in-flow(s).
  nsHTMLContainerFrame* flow = this;
  if (nsnull != prevSibling) {
    prevSibling->GetGeometricParent((nsIFrame*&)flow);
  }

  // Create the new frame as a child of the same parent as prevSibling
  nsIFrame* newFrame;
  nsresult rv = nsHTMLBase::CreateFrame(aPresContext, flow, aChild, nsnull,
                                        newFrame);
  if (NS_OK != rv) {
    return rv;
  }
  flow->mChildCount++;

  // Place the new frame into the parents sibling list
  if (nsnull == prevSibling) {
    newFrame->SetNextSibling(flow->mFirstChild);
    flow->mFirstChild = newFrame;
  }
  else {
    nsIFrame* nextSibling;
    prevSibling->GetNextSibling(nextSibling);
    newFrame->SetNextSibling(nextSibling);
    prevSibling->SetNextSibling(newFrame);
    if (nsnull == nextSibling) {
      // newFrame ended up being flow's last child
      flow->mLastContentIsComplete = PR_TRUE;
    }
  }
  flow->mLastContentOffset++;

  // Generate a reflow command
  nsIReflowCommand* cmd;
  rv = NS_NewHTMLReflowCommand(&cmd, flow,
                               nsIReflowCommand::FrameInserted,
                               newFrame);
  if (NS_OK != rv) {
    return rv;
  }
  aShell->AppendReflowCommand(cmd);
  NS_RELEASE(cmd);

  // Fix up the next-in-flows of parent now that it has a new child
  flow = (nsHTMLContainerFrame*) flow->mNextInFlow;
  while (nsnull != flow) {
    flow->mFirstContentOffset++;
    flow->mLastContentOffset++;
  }
  return rv;
}

NS_IMETHODIMP
nsHTMLContainerFrame::ContentDeleted(nsIPresShell*   aShell,
                                     nsIPresContext* aPresContext,
                                     nsIContent*     aContainer,
                                     nsIContent*     aChild,
                                     PRInt32         aIndexInParent)
{
  NS_ASSERTION(!IsPseudoFrame(), "pseudos not supported here");

  // Find the frame that precedes the deletion point
  nsHTMLContainerFrame* flow;
  nsIFrame* deadFrame;
  nsIFrame* prevSibling;
  if (aIndexInParent > 0) {
    nsIContent* precedingContent = aContainer->ChildAt(aIndexInParent - 1);
    prevSibling = aShell->FindFrameWithContent(precedingContent);
    NS_RELEASE(precedingContent);

    // The frame may have a next-in-flow. Get the last-in-flow
    nsIFrame* nextInFlow;
    do {
      prevSibling->GetNextInFlow(nextInFlow);
      if (nsnull != nextInFlow) {
        prevSibling = nextInFlow;
      }
    } while (nsnull != nextInFlow);

    // Get the dead frame (maybe)
    prevSibling->GetGeometricParent((nsIFrame*&)flow);
    prevSibling->GetNextSibling(deadFrame);
    if (nsnull == deadFrame) {
      // The deadFrame must be prevSibling's parent's next-in-flows
      // first frame. Therefore it doesn't have a prevSibling.
      flow = (nsHTMLContainerFrame*) flow->mNextInFlow;
      if (nsnull != flow) {
        deadFrame = flow->mFirstChild;
      }
      prevSibling = nsnull;
    }
  }
  else {
    prevSibling = nsnull;
    flow = this;
    deadFrame = flow->mFirstChild;
  }
  NS_ASSERTION(nsnull != deadFrame, "yikes! couldn't find frame");
  if (nsnull == deadFrame) {
    return NS_OK;
  }

  // Generate a reflow command
  nsIReflowCommand* cmd;
  nsresult rv = NS_NewHTMLReflowCommand(&cmd, flow,
                                        nsIReflowCommand::FrameDeleted);
  if (NS_OK != rv) {
    return rv;
  }
  aShell->AppendReflowCommand(cmd);
  NS_RELEASE(cmd);

  // Take the frame away; Note that we also have to take away any
  // continuations so we loop here until deadFrame is nsnull.
  while (nsnull != deadFrame) {
    // If the last frame for the flow is the frame we are deleting
    // then the flow will become complete.
    if (!flow->mLastContentIsComplete) {
      nsIFrame* lastFrame;
      flow->LastChild(lastFrame);
      if (lastFrame == deadFrame) {
        flow->mLastContentIsComplete = PR_TRUE;
      }
    }

    // Remove frame from sibling list
    nsIFrame* nextSib;
    deadFrame->GetNextSibling(nextSib);
    if (nsnull != prevSibling) {
      prevSibling->SetNextSibling(nextSib);
    }
    else {
      flow->mFirstChild = nextSib;
    }

    // Update flows child count and last-content-offset. Note that
    // only the last content needs updating when a deadFrame is
    // removed from flow (because only the children that follow the
    // deletion need renumbering).
    flow->mChildCount--;
    flow->mLastContentOffset--;

    // Break frame out of its flow and then destroy it
    nsIFrame* nextInFlow;
    deadFrame->GetNextInFlow(nextInFlow);
    deadFrame->BreakFromNextFlow();
    deadFrame->DeleteFrame(*aPresContext);
    deadFrame = nextInFlow;

    if (nsnull != deadFrame) {
      // Get the parent of deadFrame's continuation
      deadFrame->GetGeometricParent((nsIFrame*&) flow);

      // When we move to a next-in-flow then the deadFrame will be the
      // first child of the new parent. Therefore we know that
      // prevSibling will be null.
      prevSibling = nsnull;
    }
  }

  // Repair any remaining next-in-flows content offsets; these are the
  // next-in-flows the follow the last flow container that contained
  // one of the deadFrame's. Therefore both content offsets need
  // updating (because all the children are following the deletion).
  flow = (nsHTMLContainerFrame*) flow->mNextInFlow;
  while (nsnull != flow) {
    flow->mFirstContentOffset--;
    flow->mLastContentOffset--;
    flow = (nsHTMLContainerFrame*) flow->mNextInFlow;
  }

  return rv;
}

nsresult
nsHTMLContainerFrame::ProcessInitialReflow(nsIPresContext* aPresContext)
{
  if (nsnull == mPrevInFlow) {
    const nsStyleDisplay* display = (const nsStyleDisplay*)
      mStyleContext->GetStyleData(eStyleStruct_Display);
    NS_FRAME_LOG(NS_FRAME_TRACE_CALLS,
                 ("nsHTMLContainerFrame::ProcessInitialReflow: display=%d",
                  display->mDisplay));
    if (NS_STYLE_DISPLAY_LIST_ITEM == display->mDisplay) {
      // This container is a list-item container. Therefore it needs a
      // bullet content object.
      nsIHTMLContent* bullet;
      nsresult rv = NS_NewHTMLBullet(&bullet);
      if (NS_OK != rv) {
        return rv;
      }

      // Insert the bullet. Do not allow an incremental reflow operation
      // to occur.
      mContent->InsertChildAt(bullet, 0, PR_FALSE);
    }
  }

  return NS_OK;
}