/**
 * 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) 2003-2006 Apple Computer, Inc.
 *
 * 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 <kdebug.h>
#include <assert.h>
#include <qpainter.h>
#include <kglobal.h>

#include "rendering/render_flow.h"
#include "rendering/render_text.h"
#include "rendering/render_table.h"
#include "rendering/render_canvas.h"
#include "rendering/render_inline.h"
#include "rendering/render_block.h"
#include "rendering/render_arena.h"
#include "rendering/render_line.h"
#include "xml/dom_nodeimpl.h"
#include "xml/dom_docimpl.h"
#include "misc/htmltags.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(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);
    while(beforeChild && beforeChild->parent() != flow && !beforeChild->parent()->isAnonymousBlock()) {
        // skip implicit containers around beforeChild
        beforeChild = beforeChild->parent();
    }
    RenderFlow* beforeChildParent = beforeChild ? static_cast<RenderFlow*>(beforeChild->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, 0); // Just treat like an append.
        else
            return beforeChildParent->addChildToFlow(newChild, beforeChild);
    }
}

void RenderFlow::addChild(RenderObject *newChild, RenderObject *beforeChild)
{
#ifdef DEBUG_LAYOUT
    kdDebug( 6040 ) << renderName() << "(RenderFlow)::addChild( " << newChild->renderName() <<
                       ", " << (beforeChild ? beforeChild->renderName() : "0") << " )" << endl;
    kdDebug( 6040 ) << "current height = " << m_height << endl;
#endif

    if (continuation())
        return addChildWithContinuation(newChild, beforeChild);
    return addChildToFlow(newChild, beforeChild);
}

void RenderFlow::deleteInlineBoxes(RenderArena* arena)
{
    RenderBox::deleteInlineBoxes(arena); //In case we upcalled
                                         //during construction
    if (m_firstLineBox) {
        if (!arena)
            arena = renderArena();
        InlineRunBox *curr=m_firstLineBox, *next=0;
        while (curr) {
            next = curr->nextLineBox();
            curr->detach(arena);
            curr = next;
        }
        m_firstLineBox = 0;
        m_lastLineBox = 0;
    }
}

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 = 0;
        else {
            prev = curr->prevLineBox();
            while (!prev->isInlineFlowBox()) {
                prev = prev->prevLineBox();
                prev->detach(arena);
            }
            m_lastLineBox = static_cast<InlineFlowBox*>(prev);
            prev->setNextLineBox(0);
        }
        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 = 0;
    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::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) {
          QValueList<RenderFlow *>::iterator it;;
          for( it = (*i.outlineObjects).begin(); it != (*i.outlineObjects).end(); ++it )
              if ((*it)->isRenderInline())
                  static_cast<RenderInline*>(*it)->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() == RELATIVE && inlineFlow->layer()) {
                KHTMLAssert(inlineFlow->isBox());
                static_cast<RenderBox*>(inlineFlow)->relativePositionOffset(left, top);
             }
        }

        RootInlineBox *lastRoot = lastLineBox() && !needsLayout() ? lastLineBox()->root() : 0;
        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 = RenderBox::lowestPosition(includeOverflowInterior, includeSelf);
    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 = kMax(bottom, lp);
        }
    }

    if (isRelPositioned()) {
        int x;
        relativePositionOffset(x, bottom);
    }

    return bottom;
}

int RenderFlow::rightmostPosition(bool includeOverflowInterior, bool includeSelf) const
{
    int right = RenderBox::rightmostPosition(includeOverflowInterior, includeSelf);
    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 = kMax(right, rp);
        }
    }

    if (isRelPositioned()) {
        int y;
        relativePositionOffset(right, y);
    }

    return right;
}

int RenderFlow::leftmostPosition(bool includeOverflowInterior, bool includeSelf) const
{
    int left = RenderBox::leftmostPosition(includeOverflowInterior, includeSelf);
    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 = kMin(left, lp);
        }
    }

    if (isRelPositioned()) {
        int y;
        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 = kMin(top, hp);
        }
    }

    if (isRelPositioned()) {
        int x;
        relativePositionOffset(x, top);
    }

    return top;
}