/**

 * Copyright (C) 1997 Martin Jones (mjones@kde.org)

 *           (C) 1997 Torben Weis (weis@kde.org)

 *           (C) 1998 Waldo Bastian (bastian@kde.org)

 *           (C) 1999 Lars Knoll (knoll@kde.org)

 *           (C) 1999 Antti Koivisto (koivisto@kde.org)

 * Copyright (C) 2003, 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.

 *

 * 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 "config.h"

#include "RenderTableCell.h"

#include "GraphicsContext.h"

#include "HTMLNames.h"

#include "HTMLTableCellElement.h"

#include "RenderTableCol.h"

#include "RenderView.h"

#include "TextStream.h"

using namespace std;

namespace WebCore {

using namespace HTMLNames;

RenderTableCell::RenderTableCell(Node* node)

    : RenderBlock(node)

    , m_row(-1)

    , m_column(-1)

    , m_rowSpan(1)

    , m_columnSpan(1)

    , m_topExtra(0)

    , m_bottomExtra(0)

    , m_widthChanged(false)

    , m_percentageHeight(0)

{

    updateFromElement();

}

void RenderTableCell::destroy()

{

    RenderTableSection* recalcSection = parent() ? section() : 0;

    RenderBlock::destroy();

    if (recalcSection)

        recalcSection->setNeedsCellRecalc();

}

void RenderTableCell::updateFromElement()

{

    Node* node = element();

    if (node && (node->hasTagName(tdTag) || node->hasTagName(thTag))) {

        HTMLTableCellElement* tc = static_cast<HTMLTableCellElement*>(node);

        int oldRSpan = m_rowSpan;

        int oldCSpan = m_columnSpan;

        m_columnSpan = tc->colSpan();

        m_rowSpan = tc->rowSpan();

        if ((oldRSpan != m_rowSpan || oldCSpan != m_columnSpan) && style() && parent()) {

            setNeedsLayoutAndPrefWidthsRecalc();

            if (section())

                section()->setNeedsCellRecalc();

        }

    }

}

Length RenderTableCell::styleOrColWidth() const

{

    Length w = style()->width();

    if (colSpan() > 1 || !w.isAuto())

        return w;

    RenderTableCol* tableCol = table()->colElement(col());

    if (tableCol) {

        w = tableCol->style()->width();

        // Column widths specified on <col> apply to the border box of the cell.

        // Percentages don't need to be handled since they're always treated this way (even when specified on the cells).

        // See Bugzilla bug 8126 for details.

        if (w.isFixed() && w.value() > 0)

            w = Length(max(0, w.value() - borderLeft() - borderRight() - paddingLeft() - paddingRight()), Fixed);

    }

    return w;

}

void RenderTableCell::calcPrefWidths()

{

    // The child cells rely on the grids up in the sections to do their calcPrefWidths work.  Normally the sections are set up early, as table

    // cells are added, but relayout can cause the cells to be freed, leaving stale pointers in the sections'

    // grids.  We must refresh those grids before the child cells try to use them.

    table()->recalcSectionsIfNeeded();

    RenderBlock::calcPrefWidths();

    if (element() && style()->autoWrap()) {

        // See if nowrap was set.

        Length w = styleOrColWidth();

        String nowrap = static_cast<Element*>(element())->getAttribute(nowrapAttr);

        if (!nowrap.isNull() && w.isFixed())

            // Nowrap is set, but we didn't actually use it because of the

            // fixed width set on the cell.  Even so, it is a WinIE/Moz trait

            // to make the minwidth of the cell into the fixed width.  They do this

            // even in strict mode, so do not make this a quirk.  Affected the top

            // of hiptop.com.

            m_minPrefWidth = max(w.value(), m_minPrefWidth);

    }

}

void RenderTableCell::calcWidth()

{

}

void RenderTableCell::setWidth(int width)

{

    if (width != m_width) {

        m_width = width;

        m_widthChanged = true;

    }

}

void RenderTableCell::layout()

{

    layoutBlock(m_widthChanged);

    m_widthChanged = false;

}

IntRect RenderTableCell::absoluteClippedOverflowRect()

{

    // If the table grid is dirty, we cannot get reliable information about adjoining cells,

    // so we ignore outside borders. This should not be a problem because it means that

    // the table is going to recalculate the grid, relayout and repaint its current rect, which

    // includes any outside borders of this cell.

    if (table()->collapseBorders() && !table()->needsSectionRecalc()) {

        bool rtl = table()->style()->direction() == RTL;

        int outlineSize = style()->outlineSize();

        int left = max(borderHalfLeft(true), outlineSize);

        int right = max(borderHalfRight(true), outlineSize);

        int top = max(borderHalfTop(true), outlineSize);

        int bottom = max(borderHalfBottom(true), outlineSize);

        if (left && !rtl || right && rtl) {

            if (RenderTableCell* before = table()->cellBefore(this)) {

                top = max(top, before->borderHalfTop(true));

                bottom = max(bottom, before->borderHalfBottom(true));

            }

        }

        if (left && rtl || right && !rtl) {

            if (RenderTableCell* after = table()->cellAfter(this)) {

                top = max(top, after->borderHalfTop(true));

                bottom = max(bottom, after->borderHalfBottom(true));

            }

        }

        if (top) {

            if (RenderTableCell* above = table()->cellAbove(this)) {

                left = max(left, above->borderHalfLeft(true));

                right = max(right, above->borderHalfRight(true));

            }

        }

        if (bottom) {

            if (RenderTableCell* below = table()->cellBelow(this)) {

                left = max(left, below->borderHalfLeft(true));

                right = max(right, below->borderHalfRight(true));

            }

        }

        left = max(left, -overflowLeft(false));

        top = max(top, -overflowTop(false) - borderTopExtra());

        IntRect r(-left, -borderTopExtra() - top, left + max(width() + right, overflowWidth(false)), borderTopExtra() + top + max(height() + bottom + borderBottomExtra(), overflowHeight(false)));

        if (RenderView* v = view())

            r.move(v->layoutDelta());

        computeAbsoluteRepaintRect(r);

        return r;

    }

    return RenderBlock::absoluteClippedOverflowRect();

}

void RenderTableCell::computeAbsoluteRepaintRect(IntRect& r, bool fixed)

{

    r.setY(r.y() + m_topExtra);

    RenderView* v = view();

    if (!v || !v->layoutState())

        r.move(-parent()->xPos(), -parent()->yPos()); // Rows are in the same coordinate space, so don't add their offset in.

    RenderBlock::computeAbsoluteRepaintRect(r, fixed);

}

bool RenderTableCell::absolutePosition(int& xPos, int& yPos, bool fixed) const

{

    bool result = RenderBlock::absolutePosition(xPos, yPos, fixed);

    RenderView* v = view();

    if (!v || !v->layoutState()) {

        xPos -= parent()->xPos(); // Rows are in the same coordinate space, so don't add their offset in.

        yPos -= parent()->yPos();

    }

    return result;

}

short RenderTableCell::baselinePosition(bool /*firstLine*/, bool /*isRootLineBox*/) const

{

    RenderObject* o = firstChild();

    int offset = paddingTop() + borderTop();

    if (!o)

        return offset + contentHeight();

    while (o->firstChild() && !o->isReplaced()) {

        if (!o->isInline())

            offset += o->paddingTop() + o->borderTop();

        o = o->firstChild();

    }

    if (!o->isInline())

        return paddingTop() + borderTop() + contentHeight();

    offset += o->baselinePosition(true);

    return offset;

}

void RenderTableCell::setStyle(RenderStyle* newStyle)

{

    if (parent() && section() && style() && style()->height() != newStyle->height())

        section()->setNeedsCellRecalc();

    newStyle->setDisplay(TABLE_CELL);

    if (newStyle->whiteSpace() == KHTML_NOWRAP) {

        // Figure out if we are really nowrapping or if we should just

        // use normal instead.  If the width of the cell is fixed, then

        // we don't actually use NOWRAP.

        if (newStyle->width().isFixed())

            newStyle->setWhiteSpace(NORMAL);

        else

            newStyle->setWhiteSpace(NOWRAP);

    }

    RenderBlock::setStyle(newStyle);

    setHasBoxDecorations(true);

}

bool RenderTableCell::requiresLayer()

{

    return isPositioned() || isTransparent() || hasOverflowClip();

}

// The following rules apply for resolving conflicts and figuring out which border

// to use.

// (1) Borders with the 'border-style' of 'hidden' take precedence over all other conflicting 

// borders. Any border with this value suppresses all borders at this location.

// (2) Borders with a style of 'none' have the lowest priority. Only if the border properties of all 

// the elements meeting at this edge are 'none' will the border be omitted (but note that 'none' is 

// the default value for the border style.)

// (3) If none of the styles are 'hidden' and at least one of them is not 'none', then narrow borders 

// are discarded in favor of wider ones. If several have the same 'border-width' then styles are preferred 

// in this order: 'double', 'solid', 'dashed', 'dotted', 'ridge', 'outset', 'groove', and the lowest: 'inset'.

// (4) If border styles differ only in color, then a style set on a cell wins over one on a row, 

// which wins over a row group, column, column group and, lastly, table. It is undefined which color 

// is used when two elements of the same type disagree.

static CollapsedBorderValue compareBorders(const CollapsedBorderValue& border1, const CollapsedBorderValue& border2)

{

    // Sanity check the values passed in.  If either is null, return the other.

    if (!border2.exists())

        return border1;

    if (!border1.exists())

        return border2;

    // Rule #1 above.

    if (border1.style() == BHIDDEN || border2.style() == BHIDDEN)

        return CollapsedBorderValue(); // No border should exist at this location.

    // Rule #2 above.  A style of 'none' has lowest priority and always loses to any other border.

    if (border2.style() == BNONE)

        return border1;

    if (border1.style() == BNONE)

        return border2;

    // The first part of rule #3 above. Wider borders win.

    if (border1.width() != border2.width())

        return border1.width() > border2.width() ? border1 : border2;

    // The borders have equal width.  Sort by border style.

    if (border1.style() != border2.style())

        return border1.style() > border2.style() ? border1 : border2;

    // The border have the same width and style.  Rely on precedence (cell over row over row group, etc.)

    return border1.precedence >= border2.precedence ? border1 : border2;

}

CollapsedBorderValue RenderTableCell::collapsedLeftBorder(bool rtl) const

{

    RenderTable* tableElt = table();

    bool leftmostColumn;

    if (!rtl)

        leftmostColumn = col() == 0;

    else {

        int effCol = tableElt->colToEffCol(col() + colSpan() - 1);

        leftmostColumn = effCol == tableElt->numEffCols() - 1;

    }

    // For border left, we need to check, in order of precedence:

    // (1) Our left border.

    CollapsedBorderValue result(&style()->borderLeft(), BCELL);

    // (2) The right border of the cell to the left.

    RenderTableCell* prevCell = rtl ? tableElt->cellAfter(this) : tableElt->cellBefore(this);

    if (prevCell) {

        result = compareBorders(result, CollapsedBorderValue(&prevCell->style()->borderRight(), BCELL));

        if (!result.exists())

            return result;

    } else if (leftmostColumn) {

        // (3) Our row's left border.

        result = compareBorders(result, CollapsedBorderValue(&parent()->style()->borderLeft(), BROW));

        if (!result.exists())

            return result;

        // (4) Our row group's left border.

        result = compareBorders(result, CollapsedBorderValue(&section()->style()->borderLeft(), BROWGROUP));

        if (!result.exists())

            return result;

    }

    // (5) Our column and column group's left borders.

    bool startColEdge;

    bool endColEdge;

    RenderTableCol* colElt = tableElt->colElement(col() + (rtl ? colSpan() - 1 : 0), &startColEdge, &endColEdge);

    if (colElt && (!rtl ? startColEdge : endColEdge)) {

        result = compareBorders(result, CollapsedBorderValue(&colElt->style()->borderLeft(), BCOL));

        if (!result.exists())

            return result;

        if (colElt->parent()->isTableCol() && (!rtl ? !colElt->previousSibling() : !colElt->nextSibling())) {

            result = compareBorders(result, CollapsedBorderValue(&colElt->parent()->style()->borderLeft(), BCOLGROUP));

            if (!result.exists())

                return result;

        }

    }

    // (6) The right border of the column to the left.

    if (!leftmostColumn) {

        colElt = tableElt->colElement(col() + (rtl ? colSpan() : -1), &startColEdge, &endColEdge);

        if (colElt && (!rtl ? endColEdge : startColEdge)) {

            result = compareBorders(result, CollapsedBorderValue(&colElt->style()->borderRight(), BCOL));

            if (!result.exists())

                return result;

        }

    } else {

        // (7) The table's left border.

        result = compareBorders(result, CollapsedBorderValue(&tableElt->style()->borderLeft(), BTABLE));

        if (!result.exists())

            return result;

    }

    return result;

}

CollapsedBorderValue RenderTableCell::collapsedRightBorder(bool rtl) const

{

    RenderTable* tableElt = table();

    bool rightmostColumn;

    if (rtl)

        rightmostColumn = col() == 0;

    else {

        int effCol = tableElt->colToEffCol(col() + colSpan() - 1);

        rightmostColumn = effCol == tableElt->numEffCols() - 1;

    }

    // For border right, we need to check, in order of precedence:

    // (1) Our right border.

    CollapsedBorderValue result = CollapsedBorderValue(&style()->borderRight(), BCELL);

    // (2) The left border of the cell to the right.

    if (!rightmostColumn) {

        RenderTableCell* nextCell = rtl ? tableElt->cellBefore(this) : tableElt->cellAfter(this);

        if (nextCell && nextCell->style()) {

            result = compareBorders(result, CollapsedBorderValue(&nextCell->style()->borderLeft(), BCELL));

            if (!result.exists())

                return result;

        }

    } else {

        // (3) Our row's right border.

        result = compareBorders(result, CollapsedBorderValue(&parent()->style()->borderRight(), BROW));

        if (!result.exists())

            return result;

        // (4) Our row group's right border.

        result = compareBorders(result, CollapsedBorderValue(&section()->style()->borderRight(), BROWGROUP));

        if (!result.exists())

            return result;

    }

    // (5) Our column and column group's right borders.

    bool startColEdge;

    bool endColEdge;

    RenderTableCol* colElt = tableElt->colElement(col() + (rtl ? 0 : colSpan() - 1), &startColEdge, &endColEdge);

    if (colElt && (!rtl ? endColEdge : startColEdge)) {

        result = compareBorders(result, CollapsedBorderValue(&colElt->style()->borderRight(), BCOL));

        if (!result.exists())

            return result;

        if (colElt->parent()->isTableCol() && (!rtl ? !colElt->nextSibling() : !colElt->previousSibling())) {

            result = compareBorders(result, CollapsedBorderValue(&colElt->parent()->style()->borderRight(), BCOLGROUP));

            if (!result.exists())

                return result;

        }

    }

    // (6) The left border of the column to the right.

    if (!rightmostColumn) {

        colElt = tableElt->colElement(col() + (rtl ? -1 : colSpan()), &startColEdge, &endColEdge);

        if (colElt && (!rtl ? startColEdge : endColEdge)) {

            result = compareBorders(result, CollapsedBorderValue(&colElt->style()->borderLeft(), BCOL));

            if (!result.exists())

                return result;

        }

    } else {

        // (7) The table's right border.

        result = compareBorders(result, CollapsedBorderValue(&tableElt->style()->borderRight(), BTABLE));

        if (!result.exists())

            return result;

    }

    return result;

}

CollapsedBorderValue RenderTableCell::collapsedTopBorder() const

{

    // For border top, we need to check, in order of precedence:

    // (1) Our top border.

    CollapsedBorderValue result = CollapsedBorderValue(&style()->borderTop(), BCELL);

    RenderTableCell* prevCell = table()->cellAbove(this);

    if (prevCell) {

        // (2) A previous cell's bottom border.

        result = compareBorders(result, CollapsedBorderValue(&prevCell->style()->borderBottom(), BCELL));

        if (!result.exists()) 

            return result;

    }

    // (3) Our row's top border.

    result = compareBorders(result, CollapsedBorderValue(&parent()->style()->borderTop(), BROW));

    if (!result.exists())

        return result;

    // (4) The previous row's bottom border.

    if (prevCell) {

        RenderObject* prevRow = 0;

        if (prevCell->section() == section())

            prevRow = parent()->previousSibling();

        else

            prevRow = prevCell->section()->lastChild();

        if (prevRow) {

            result = compareBorders(result, CollapsedBorderValue(&prevRow->style()->borderBottom(), BROW));

            if (!result.exists())

                return result;

        }

    }

    // Now check row groups.

    RenderTableSection* currSection = section();

    if (!row()) {

        // (5) Our row group's top border.

        result = compareBorders(result, CollapsedBorderValue(&currSection->style()->borderTop(), BROWGROUP));

        if (!result.exists())

            return result;

        // (6) Previous row group's bottom border.

        currSection = table()->sectionAbove(currSection);

        if (currSection) {

            result = compareBorders(result, CollapsedBorderValue(&currSection->style()->borderBottom(), BROWGROUP));

            if (!result.exists())

                return result;

        }

    }

    if (!currSection) {

        // (8) Our column and column group's top borders.

        RenderTableCol* colElt = table()->colElement(col());

        if (colElt) {

            result = compareBorders(result, CollapsedBorderValue(&colElt->style()->borderTop(), BCOL));

            if (!result.exists())

                return result;

            if (colElt->parent()->isTableCol()) {

                result = compareBorders(result, CollapsedBorderValue(&colElt->parent()->style()->borderTop(), BCOLGROUP));

                if (!result.exists())

                    return result;

            }

        }

        // (9) The table's top border.

        result = compareBorders(result, CollapsedBorderValue(&table()->style()->borderTop(), BTABLE));

        if (!result.exists())

            return result;

    }

    return result;

}

CollapsedBorderValue RenderTableCell::collapsedBottomBorder() const

{

    // For border top, we need to check, in order of precedence:

    // (1) Our bottom border.

    CollapsedBorderValue result = CollapsedBorderValue(&style()->borderBottom(), BCELL);

    RenderTableCell* nextCell = table()->cellBelow(this);

    if (nextCell) {

        // (2) A following cell's top border.

        result = compareBorders(result, CollapsedBorderValue(&nextCell->style()->borderTop(), BCELL));

        if (!result.exists())

            return result;

    }

    // (3) Our row's bottom border. (FIXME: Deal with rowspan!)

    result = compareBorders(result, CollapsedBorderValue(&parent()->style()->borderBottom(), BROW));

    if (!result.exists())

        return result;

    // (4) The next row's top border.

    if (nextCell) {