/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* 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/. */

/*

 * a list of the recomputation that needs to be done in response to a

 * style change

 */

#include "nsStyleChangeList.h"

#include "mozilla/dom/ElementInlines.h"

#include "nsCSSFrameConstructor.h"

#include "nsIContent.h"

#include "nsIFrame.h"

void

nsStyleChangeList::AppendChange(nsIFrame* aFrame, nsIContent* aContent, nsChangeHint aHint)

{

  MOZ_ASSERT(aFrame || (aHint & nsChangeHint_ReconstructFrame),

             "must have frame");

  MOZ_ASSERT(aHint, "No hint to process?");

  MOZ_ASSERT(!(aHint & nsChangeHint_NeutralChange),

             "Neutral changes do not need extra processing, "

             "and should be stripped out");

  MOZ_ASSERT(aContent || !(aHint & nsChangeHint_ReconstructFrame),

             "must have content");

  // XXXbz we should make this take Element instead of nsIContent

  MOZ_ASSERT(!aContent || aContent->IsElement() ||

             // display:contents elements posts the changes for their children:

             (aFrame && aContent->GetFlattenedTreeParentElementForStyle() &&

              Servo_Element_IsDisplayContents(

                aContent->GetFlattenedTreeParentElementForStyle())) ||

             (aContent->IsText() &&

              aContent->HasFlag(NODE_NEEDS_FRAME) &&

              aHint & nsChangeHint_ReconstructFrame),

             "Shouldn't be trying to restyle non-elements directly, "

             "except if it's a display:contents child or a text node "

             "doing lazy frame construction");

  MOZ_ASSERT(!(aHint & nsChangeHint_AllReflowHints) ||

             (aHint & nsChangeHint_NeedReflow),

             "Reflow hint bits set without actually asking for a reflow");

  if (aHint & nsChangeHint_ReconstructFrame) {

    // If Servo fires reconstruct at a node, it is the only change hint fired at

    // that node.

    // Note: Because we check whether |aHint| is a reconstruct above (which is

    // necessary to avoid debug test timeouts on certain crashtests), this check

    // will not find bugs where we add a non-reconstruct hint for an element after

    // adding a reconstruct. This is ok though, since ProcessRestyledFrames will

    // handle that case via mDestroyedFrames.

#ifdef DEBUG

    for (size_t i = 0; i < Length(); ++i) {

      MOZ_ASSERT(aContent != (*this)[i].mContent ||

                 !((*this)[i].mHint & nsChangeHint_ReconstructFrame),

                 "Should not append a non-ReconstructFrame hint after \

                 appending a ReconstructFrame hint for the same \

                 content.");

    }

#endif

  }

  if (!IsEmpty() && aFrame && aFrame == LastElement().mFrame) {

    LastElement().mHint |= aHint;

    return;

  }

  AppendElement(nsStyleChangeData { aFrame, aContent, aHint });

}