File indexing completed on 2024-04-28 15:23:59

 /**
  * This file is part of the html renderer for KDE.
  *
  * Copyright (C) 1999-2003 Lars Knoll (knoll@kde.org)
  *           (C) 1999-2003 Antti Koivisto (koivisto@kde.org)
  *           (C) 2002-2003 Dirk Mueller (mueller@kde.org)
  *           (C) 2003-2007 Apple Computer, Inc.
  *           (C) 2007 Germain Garand (germain@ebooksfrance.org)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */
 // -------------------------------------------------------------------------
 
 #include "render_flow.h"
 
 #include "khtml_debug.h"
 #include <assert.h>
 #include <QPainter>
 
 #include "render_text.h"
 #include "render_table.h"
 #include "render_canvas.h"
 #include "render_inline.h"
 #include "render_block.h"
 #include "render_arena.h"
 #include <xml/dom_nodeimpl.h>
 #include <xml/dom_docimpl.h>
 #include <html/html_formimpl.h>
 
 #include <khtmlview.h>
 
 using namespace DOM;
 using namespace khtml;
 
 RenderFlow *RenderFlow::createFlow(DOM::NodeImpl *node, RenderStyle *style, RenderArena *arena)
 {
     RenderFlow *result;
     if (style->display() == INLINE) {
         result = new(arena) RenderInline(node);
     } else {
         result = new(arena) RenderBlock(node);
     }
     result->setStyle(style);
     return result;
 }
 
 RenderFlow *RenderFlow::continuationBefore(const RenderObject *beforeChild)
 {
     if (beforeChild && beforeChild->parent() == this) {
         return this;
     }
 
     RenderFlow *curr = continuation();
     RenderFlow *nextToLast = this;
     RenderFlow *last = this;
     while (curr) {
         if (beforeChild && beforeChild->parent() == curr) {
             if (curr->firstChild() == beforeChild) {
                 return last;
             }
             return curr;
         }
 
         nextToLast = last;
         last = curr;
         curr = curr->continuation();
     }
 
     if (!beforeChild && !last->firstChild()) {
         return nextToLast;
     }
     return last;
 }
 
 void RenderFlow::addChildWithContinuation(RenderObject *newChild, RenderObject *beforeChild)
 {
     RenderFlow *flow = continuationBefore(beforeChild);
 
     RenderObject *bc = beforeChild;
     while (bc && bc->parent() != flow && !bc->parent()->isAnonymousBlock()) {
         // skip implicit containers around beforeChild
         bc = bc->parent();
     }
 
     RenderFlow *beforeChildParent = bc ? static_cast<RenderFlow *>(bc->parent()) :
                                     (flow->continuation() ? flow->continuation() : flow);
 
     if (newChild->isFloatingOrPositioned()) {
         return beforeChildParent->addChildToFlow(newChild, beforeChild);
     }
 
     // A continuation always consists of two potential candidates: an inline or an anonymous
     // block box holding block children.
     bool childInline = newChild->isInline();
     bool bcpInline = beforeChildParent->isInline();
     bool flowInline = flow->isInline();
 
     if (flow == beforeChildParent) {
         return flow->addChildToFlow(newChild, beforeChild);
     } else {
         // The goal here is to match up if we can, so that we can coalesce and create the
         // minimal # of continuations needed for the inline.
         if (childInline == bcpInline) {
             return beforeChildParent->addChildToFlow(newChild, beforeChild);
         } else if (flowInline == childInline) {
             return flow->addChildToFlow(newChild, nullptr);    // Just treat like an append.
         } else {
             return beforeChildParent->addChildToFlow(newChild, beforeChild);
         }
     }
 }
 
 void RenderFlow::addChild(RenderObject *newChild, RenderObject *beforeChild)
 {
 #ifdef DEBUG_LAYOUT
     // qCDebug(KHTML_LOG) << renderName() << "(RenderFlow)::addChild( " << newChild->renderName() <<
     // ", " << (beforeChild ? beforeChild->renderName() : "0") << " )";
     // qCDebug(KHTML_LOG) << "current height = " << m_height;
 #endif
 
     if (continuation()) {
         return addChildWithContinuation(newChild, beforeChild);
     }
     return addChildToFlow(newChild, beforeChild);
 }
 
 void RenderFlow::extractLineBox(InlineFlowBox *box)
 {
     m_lastLineBox = box->prevFlowBox();
     if (box == m_firstLineBox) {
         m_firstLineBox = nullptr;
     }
     if (box->prevLineBox()) {
         box->prevLineBox()->setNextLineBox(nullptr);
     }
     box->setPreviousLineBox(nullptr);
     for (InlineRunBox *curr = box; curr; curr = curr->nextLineBox()) {
         curr->setExtracted();
     }
 }
 
 void RenderFlow::attachLineBox(InlineFlowBox *box)
 {
     if (m_lastLineBox) {
         m_lastLineBox->setNextLineBox(box);
         box->setPreviousLineBox(m_lastLineBox);
     } else {
         m_firstLineBox = box;
     }
     InlineFlowBox *last = box;
     for (InlineFlowBox *curr = box; curr; curr = curr->nextFlowBox()) {
         curr->setExtracted(false);
         last = curr;
     }
     m_lastLineBox = last;
 }
 
 void RenderFlow::removeInlineBox(InlineBox *_box)
 {
     if (_box->isInlineFlowBox()) {
         InlineFlowBox *box = static_cast<InlineFlowBox *>(_box);
         if (box == m_firstLineBox) {
             m_firstLineBox = box->nextFlowBox();
         }
         if (box == m_lastLineBox) {
             m_lastLineBox = box->prevFlowBox();
         }
         if (box->nextLineBox()) {
             box->nextLineBox()->setPreviousLineBox(box->prevLineBox());
         }
         if (box->prevLineBox()) {
             box->prevLineBox()->setNextLineBox(box->nextLineBox());
         }
     }
     RenderBox::removeInlineBox(_box);
 }
 
 void RenderFlow::deleteInlineBoxes(RenderArena *arena)
 {
     if (m_firstLineBox) {
         if (!arena) {
             arena = renderArena();
         }
         InlineRunBox *curr = m_firstLineBox, *next = nullptr;
         while (curr) {
             next = curr->nextLineBox();
             if (!curr->isPlaceHolderBox()) {
                 curr->detach(arena, true /*noRemove*/);
             }
             curr = next;
         }
         m_firstLineBox = nullptr;
         m_lastLineBox = nullptr;
     }
 }
 
 void RenderFlow::dirtyInlineBoxes(bool fullLayout, bool isRootLineBox)
 {
     if (!isRootLineBox && (isReplaced() || isPositioned())) {
         return RenderBox::dirtyInlineBoxes(fullLayout, isRootLineBox);
     }
 
     if (fullLayout) {
         deleteInlineBoxes();
     } else {
         for (InlineRunBox *curr = firstLineBox(); curr; curr = curr->nextLineBox()) {
             curr->dirtyInlineBoxes();
         }
     }
 }
 
 void RenderFlow::deleteLastLineBox(RenderArena *arena)
 {
     if (m_lastLineBox) {
         if (!arena) {
             arena = renderArena();
         }
         InlineRunBox *curr = m_lastLineBox, *prev = m_lastLineBox;
         if (m_firstLineBox == m_lastLineBox) {
             m_firstLineBox = m_lastLineBox = nullptr;
         } else {
             prev = curr->prevLineBox();
             while (!prev->isInlineFlowBox()) {
                 prev = prev->prevLineBox();
                 prev->detach(arena);
             }
             m_lastLineBox = static_cast<InlineFlowBox *>(prev);
             prev->setNextLineBox(nullptr);
         }
         if (curr->parent()) {
             curr->parent()->removeFromLine(curr);
         }
         curr->detach(arena);
     }
 }
 
 InlineBox *RenderFlow::createInlineBox(bool makePlaceHolderBox, bool isRootLineBox)
 {
     if (!isRootLineBox &&
             (isReplaced() || makePlaceHolderBox)) {      // Inline tables and inline blocks
         return RenderBox::createInlineBox(false, false);    // (or positioned element placeholders).
     }
 
     InlineFlowBox *flowBox = nullptr;
     if (isInlineFlow()) {
         flowBox = new(renderArena()) InlineFlowBox(this);
     } else {
         flowBox = new(renderArena()) RootInlineBox(this);
     }
 
     if (!m_firstLineBox) {
         m_firstLineBox = m_lastLineBox = flowBox;
     } else {
         m_lastLineBox->setNextLineBox(flowBox);
         flowBox->setPreviousLineBox(m_lastLineBox);
         m_lastLineBox = flowBox;
     }
 
     return flowBox;
 }
 
 void RenderFlow::dirtyLinesFromChangedChild(RenderObject *child)
 {
     if (!parent() || (selfNeedsLayout() && !isInlineFlow()) || isTable()) {
         return;
     }
 
     // If we have no first line box, then just bail early.
     if (!firstLineBox()) {
         // For an empty inline, propagate the check up to our parent, unless the parent
         // is already dirty.
         if (isInline() && !parent()->selfNeedsLayout() && parent()->isInlineFlow()) {
             static_cast<RenderFlow *>(parent())->dirtyLinesFromChangedChild(this);
         }
         return;
     }
 
     // Try to figure out which line box we belong in.  First try to find a previous
     // line box by examining our siblings.  If we didn't find a line box, then use our
     // parent's first line box.
     RootInlineBox *box = nullptr;
     RenderObject *curr = nullptr;
     for (curr = child->previousSibling(); curr; curr = curr->previousSibling()) {
         if (curr->isFloatingOrPositioned()) {
             continue;
         }
 
         if (curr->isReplaced() && curr->isBox()) {
             InlineBox *placeHolderBox = static_cast<RenderBox *>(curr)->placeHolderBox();
             if (placeHolderBox) {
                 box = placeHolderBox->root();
             }
         } else if (curr->isText()) {
             InlineTextBox *textBox = static_cast<RenderText *>(curr)->lastTextBox();
             if (textBox) {
                 box = textBox->root();
             }
         } else if (curr->isInlineFlow()) {
             InlineRunBox *runBox = static_cast<RenderFlow *>(curr)->lastLineBox();
             if (runBox) {
                 box = runBox->root();
             }
         }
 
         if (box) {
             break;
         }
     }
     if (!box) {
         box = firstLineBox()->root();
     }
 
     // If we found a line box, then dirty it.
     if (box) {
         RootInlineBox *adjacentBox;
         box->markDirty();
 
         // dirty the adjacent lines that might be affected
         // NOTE: we dirty the previous line because RootInlineBox objects cache
         // the address of the first object on the next line after a BR, which we may be
         // invalidating here.  For more info, see how RenderBlock::layoutInlineChildren
         // calls setLineBreakInfo with the result of findNextLineBreak.  findNextLineBreak,
         // despite the name, actually returns the first RenderObject after the BR.
 
         adjacentBox = box->prevRootBox();
         if (adjacentBox) {
             adjacentBox->markDirty();
         }
         if (child->isBR() || (curr && curr->isBR())) {
             adjacentBox = box->nextRootBox();
             if (adjacentBox) {
                 adjacentBox->markDirty();
             }
         }
     }
 }
 
 QList< QRectF > RenderFlow::getClientRects()
 {
     if (isRenderInline() && isInlineFlow()) {
         QList<QRectF> list;
 
         InlineFlowBox *child = firstLineBox();
         if (child) {
             int x = 0, y = 0;
             absolutePosition(x,y);
             do {
                 QRectF rect(x + child->xPos(), y + child->yPos(), child->width(), child->height());
                 list.append(clientRectToViewport(rect));
                 child = child->nextFlowBox();
             } while (child);
         }
 
         // In case our flow is splitted by blocks
         for (RenderObject *cont = continuation(); cont; cont = cont->continuation()) {
             list.append(cont->getClientRects());
         }
 
         // Empty Flow, return the Flow itself
         if (list.isEmpty()) {
             return RenderObject::getClientRects();
         }
 
         return list;
     } else {
         return RenderObject::getClientRects();
     }
 }
 
 void RenderFlow::detach()
 {
     if (continuation()) {
         continuation()->detach();
     }
     m_continuation = nullptr;
 
     // Make sure to destroy anonymous children first while they are still connected to the rest of the tree, so that they will
     // properly dirty line boxes that they are removed from.  Effects that do :before/:after only on hover could crash otherwise.
     detachRemainingChildren();
 
     if (!documentBeingDestroyed()) {
         if (m_firstLineBox) {
             // We can't wait for RenderContainer::destroy to clear the selection,
             // because by then we will have nuked the line boxes.
             if (isSelectionBorder()) {
                 canvas()->clearSelection();
             }
 
             // If line boxes are contained inside a root, that means we're an inline.
             // In that case, we need to remove all the line boxes so that the parent
             // lines aren't pointing to deleted children. If the first line box does
             // not have a parent that means they are either already disconnected or
             // root lines that can just be destroyed without disconnecting.
             if (m_firstLineBox->parent()) {
                 for (InlineRunBox *box = m_firstLineBox; box; box = box->nextLineBox()) {
                     box->remove();
                 }
             }
 
             // If we are an anonymous block, then our line boxes might have children
             // that will outlast this block. In the non-anonymous block case those
             // children will be destroyed by the time we return from this function.
             if (isAnonymousBlock()) {
                 for (InlineFlowBox *box = m_firstLineBox; box; box = box->nextFlowBox()) {
                     while (InlineBox *childBox = box->firstChild()) {
                         childBox->remove();
                     }
                 }
             }
         } else if (isInline() && parent())
             // empty inlines propagate linebox dirtying to the parent
         {
             parent()->dirtyLinesFromChangedChild(this);
         }
     }
 
     deleteInlineBoxes();
 
     RenderBox::detach();
 }
 
 void RenderFlow::paintLines(PaintInfo &i, int _tx, int _ty)
 {
     // Only paint during the foreground/selection phases.
     if (i.phase != PaintActionForeground && i.phase != PaintActionSelection && i.phase != PaintActionOutline) {
         return;
     }
 
     if (!firstLineBox()) {
         return;
     }
 
     // We can check the first box and last box and avoid painting if we don't
     // intersect.  This is a quick short-circuit that we can take to avoid walking any lines.
     // FIXME: This check is flawed in two extremely obscure ways.
     // (1) If some line in the middle has a huge overflow, it might actually extend below the last line.
     // (2) The overflow from an inline block on a line is not reported to the line.
     int maxOutlineSize = maximalOutlineSize(i.phase);
     int yPos = firstLineBox()->root()->topOverflow() - maxOutlineSize;
     int h = maxOutlineSize + lastLineBox()->root()->bottomOverflow() - yPos;
     yPos += _ty;
     if ((yPos >= i.r.y() + i.r.height()) || (yPos + h <= i.r.y())) {
         return;
     }
     for (InlineFlowBox *curr = firstLineBox(); curr; curr = curr->nextFlowBox()) {
         yPos = curr->root()->topOverflow() - maxOutlineSize;
         h = curr->root()->bottomOverflow() + maxOutlineSize - yPos;
         yPos += _ty;
         if ((yPos < i.r.y() + i.r.height()) && (yPos + h > i.r.y())) {
             curr->paint(i, _tx, _ty);
         }
     }
 
     if (i.phase == PaintActionOutline && i.outlineObjects) {
         foreach (RenderFlow *oo, *i.outlineObjects)
             if (oo->isRenderInline()) {
                 static_cast<RenderInline *>(oo)->paintOutlines(i.p, _tx, _ty);
             }
         i.outlineObjects->clear();
     }
 }
 
 bool RenderFlow::hitTestLines(NodeInfo &i, int x, int y, int tx, int ty, HitTestAction hitTestAction)
 {
     (void) hitTestAction;
     /*
      if (hitTestAction != HitTestForeground) // ### port hitTest
          return false;
     */
 
     if (!firstLineBox()) {
         return false;
     }
 
     // We can check the first box and last box and avoid hit testing if we don't
     // contain the point.  This is a quick short-circuit that we can take to avoid walking any lines.
     // FIXME: This check is flawed in two extremely obscure ways.
     // (1) If some line in the middle has a huge overflow, it might actually extend below the last line.
     // (2) The overflow from an inline block on a line is not reported to the line.
     if ((y >= ty + lastLineBox()->root()->bottomOverflow()) || (y < ty + firstLineBox()->root()->topOverflow())) {
         return false;
     }
 
     // See if our root lines contain the point.  If so, then we hit test
     // them further.  Note that boxes can easily overlap, so we can't make any assumptions
     // based off positions of our first line box or our last line box.
     for (InlineFlowBox *curr = lastLineBox(); curr; curr = curr->prevFlowBox()) {
         if (y >= ty + curr->root()->topOverflow() && y < ty + curr->root()->bottomOverflow()) {
             bool inside = curr->nodeAtPoint(i, x, y, tx, ty);
             if (inside) {
                 setInnerNode(i);
                 return true;
             }
         }
     }
 
     return false;
 }
 
 void RenderFlow::repaint(Priority prior)
 {
     if (isInlineFlow()) {
         // Find our leftmost position.
         int left = 0;
         // root inline box not reliably availabe during relayout
         int top = firstLineBox() ? (
                       needsLayout() ? firstLineBox()->xPos() : firstLineBox()->root()->topOverflow()
                   ) : 0;
         for (InlineRunBox *curr = firstLineBox(); curr; curr = curr->nextLineBox())
             if (curr == firstLineBox() || curr->xPos() < left) {
                 left = curr->xPos();
             }
 
         // Now invalidate a rectangle.
         int ow = style() ? style()->outlineSize() : 0;
 
         // We need to add in the relative position offsets of any inlines (including us) up to our
         // containing block.
         RenderBlock *cb = containingBlock();
         for (RenderObject *inlineFlow = this; inlineFlow && inlineFlow->isInlineFlow() && inlineFlow != cb;
                 inlineFlow = inlineFlow->parent()) {
             if (inlineFlow->style() && inlineFlow->style()->position() == PRELATIVE && inlineFlow->layer()) {
                 KHTMLAssert(inlineFlow->isBox());
                 static_cast<RenderBox *>(inlineFlow)->relativePositionOffset(left, top);
             }
         }
 
         RootInlineBox *lastRoot = lastLineBox() && !needsLayout() ? lastLineBox()->root() : nullptr;
         containingBlock()->repaintRectangle(-ow + left, -ow + top,
                                             width() + ow * 2,
                                             (lastRoot ? lastRoot->bottomOverflow() - top : height()) + ow * 2, prior);
     } else {
         if (firstLineBox() && firstLineBox()->topOverflow() < 0) {
             int ow = style() ? style()->outlineSize() : 0;
             repaintRectangle(-ow, -ow + firstLineBox()->topOverflow(),
                              effectiveWidth() + ow * 2, effectiveHeight() + ow * 2, prior);
         } else {
             return RenderBox::repaint(prior);
         }
     }
 }
 
 int
 RenderFlow::lowestPosition(bool includeOverflowInterior, bool includeSelf) const
 {
     int bottom = includeSelf && m_width > 0 ? m_height : 0;
     if (!includeOverflowInterior && hasOverflowClip()) {
         return bottom;
     }
 
     // FIXME: Come up with a way to use the layer tree to avoid visiting all the kids.
     // For now, we have to descend into all the children, since we may have a huge abs div inside
     // a tiny rel div buried somewhere deep in our child tree.  In this case we have to get to
     // the abs div.
     for (RenderObject *c = firstChild(); c; c = c->nextSibling()) {
         if (!c->isFloatingOrPositioned() && !c->isText() && !c->isInlineFlow()) {
             int lp = c->yPos() + c->lowestPosition(false);
             bottom = qMax(bottom, lp);
         }
     }
 
     if (includeSelf && isRelPositioned()) {
         int x = 0;
         relativePositionOffset(x, bottom);
     }
 
     return bottom;
 }
 
 int RenderFlow::rightmostPosition(bool includeOverflowInterior, bool includeSelf) const
 {
     int right = includeSelf && m_height > 0 ? m_width : 0;
     if (!includeOverflowInterior && hasOverflowClip()) {
         return right;
     }
 
     // FIXME: Come up with a way to use the layer tree to avoid visiting all the kids.
     // For now, we have to descend into all the children, since we may have a huge abs div inside
     // a tiny rel div buried somewhere deep in our child tree.  In this case we have to get to
     // the abs div.
     for (RenderObject *c = firstChild(); c; c = c->nextSibling()) {
         if (!c->isFloatingOrPositioned() && !c->isText() && !c->isInlineFlow()) {
             int rp = c->xPos() + c->rightmostPosition(false);
             right = qMax(right, rp);
         }
     }
 
     if (includeSelf && isRelPositioned()) {
         int y = 0;
         relativePositionOffset(right, y);
     }
 
     return right;
 }
 
 int RenderFlow::leftmostPosition(bool includeOverflowInterior, bool includeSelf) const
 {
     int left = includeSelf && m_height > 0 ? 0 : m_width;
     if (!includeOverflowInterior && hasOverflowClip()) {
         return left;
     }
 
     // FIXME: Come up with a way to use the layer tree to avoid visiting all the kids.
     // For now, we have to descend into all the children, since we may have a huge abs div inside
     // a tiny rel div buried somewhere deep in our child tree.  In this case we have to get to
     // the abs div.
     for (RenderObject *c = firstChild(); c; c = c->nextSibling()) {
         if (!c->isFloatingOrPositioned() && !c->isText() && !c->isInlineFlow()) {
             int lp = c->xPos() + c->leftmostPosition(false);
             left = qMin(left, lp);
         }
     }
 
     if (includeSelf && isRelPositioned()) {
         int y = 0;
         relativePositionOffset(left, y);
     }
 
     return left;
 }
 
 int RenderFlow::highestPosition(bool includeOverflowInterior, bool includeSelf) const
 {
     int top = RenderBox::highestPosition(includeOverflowInterior, includeSelf);
     if (!includeOverflowInterior && hasOverflowClip()) {
         return top;
     }
 
     // FIXME: Come up with a way to use the layer tree to avoid visiting all the kids.
     // For now, we have to descend into all the children, since we may have a huge abs div inside
     // a tiny rel div buried somewhere deep in our child tree.  In this case we have to get to
     // the abs div.
     for (RenderObject *c = firstChild(); c; c = c->nextSibling()) {
         if (!c->isFloatingOrPositioned() && !c->isText() && !c->isInlineFlow()) {
             int hp = c->yPos() + c->highestPosition(false);
             top = qMin(top, hp);
         }
     }
 
     if (includeSelf && isRelPositioned()) {
         int x = 0;
         relativePositionOffset(x, top);
     }
 
     return top;
 }