/*

 * 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, 2008, 2009 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 "FloatQuad.h"

#include "GraphicsContext.h"

#include "HTMLNames.h"

#include "HTMLTableCellElement.h"

#include "RenderTableCol.h"

#include "RenderView.h"

#include "TransformState.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_intrinsicPaddingTop(0)

    , m_intrinsicPaddingBottom(0)

    , m_percentageHeight(0)

{

    updateFromElement();

}

void RenderTableCell::destroy()

{

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

    RenderBlock::destroy();

    if (recalcSection)

        recalcSection->setNeedsCellRecalc();

}

void RenderTableCell::updateFromElement()

{

    Node* n = node();

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

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

        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 (!w.isAuto())

        return w;

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

    if (tableCol) {

        int colSpanCount = colSpan();

        Length colWidthSum = Length(0, Fixed);

        for (int i = 1; i <= colSpanCount; i++) {

            Length colWidth = tableCol->style()->width();

            // Percentage value should be returned only for colSpan == 1.

            // Otherwise we return original width for the cell.

            if (!colWidth.isFixed()) {

                if (colSpanCount > 1)

                    return w;

                return colWidth;

            }

            colWidthSum = Length(colWidthSum.value() + colWidth.value(), Fixed);

            tableCol = table()->nextColElement(tableCol);

            // If no next <col> tag found for the span we just return what we have for now.

            if (!tableCol)

                break;

        }

        // 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 (colWidthSum.isFixed() && colWidthSum.value() > 0)

            colWidthSum = Length(max(0, colWidthSum.value() - borderAndPaddingWidth()), Fixed);

        return colWidthSum;

    }

    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 (node() && style()->autoWrap()) {

        // See if nowrap was set.

        Length w = styleOrColWidth();

        String nowrap = static_cast<Element*>(node())->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::updateWidth(int w)

{

    if (w != width()) {

        setWidth(w);

        setCellWidthChanged(true);

    }

}

void RenderTableCell::layout()

{

    layoutBlock(cellWidthChanged());

    setCellWidthChanged(false);

}

int RenderTableCell::paddingTop(bool includeIntrinsicPadding) const

{

    return RenderBlock::paddingTop() + (includeIntrinsicPadding ? intrinsicPaddingTop() : 0);

}

int RenderTableCell::paddingBottom(bool includeIntrinsicPadding) const

{

    return RenderBlock::paddingBottom() + (includeIntrinsicPadding ? intrinsicPaddingBottom() : 0);

}

void RenderTableCell::setOverrideSize(int size)

{

    clearIntrinsicPadding();

    RenderBlock::setOverrideSize(size);

}

IntSize RenderTableCell::offsetFromContainer(RenderObject* o, const IntPoint& point) const

{

    ASSERT(o == container());

    IntSize offset = RenderBlock::offsetFromContainer(o, point);

    if (parent())

        offset.expand(-parentBox()->x(), -parentBox()->y());

    return offset;

}

IntRect RenderTableCell::clippedOverflowRectForRepaint(RenderBoxModelObject* repaintContainer)

{

    // 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())

        return RenderBlock::clippedOverflowRectForRepaint(repaintContainer);

    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, -leftVisibleOverflow());

    top = max(top, -topVisibleOverflow());

    IntRect r(-left, - top, left + max(width() + right, rightVisibleOverflow()), top + max(height() + bottom, bottomVisibleOverflow()));

    if (RenderView* v = view()) {

        // FIXME: layoutDelta needs to be applied in parts before/after transforms and

        // repaint containers. https://bugs.webkit.org/show_bug.cgi?id=23308

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

    }

    computeRectForRepaint(repaintContainer, r);

    return r;

}

void RenderTableCell::computeRectForRepaint(RenderBoxModelObject* repaintContainer, IntRect& r, bool fixed)

{

    if (repaintContainer == this)

        return;

    r.setY(r.y());

    RenderView* v = view();

    if ((!v || !v->layoutStateEnabled() || repaintContainer) && parent())

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

    RenderBlock::computeRectForRepaint(repaintContainer, r, fixed);

}

int RenderTableCell::baselinePosition(bool firstLine, bool isRootLineBox) const

{

    if (isRootLineBox)

        return RenderBox::baselinePosition(firstLine, isRootLineBox);

    // <http://www.w3.org/TR/2007/CR-CSS21-20070719/tables.html#height-layout>: The baseline of a cell is the baseline of

    // the first in-flow line box in the cell, or the first in-flow table-row in the cell, whichever comes first. If there

    // is no such line box or table-row, the baseline is the bottom of content edge of the cell box.

    int firstLineBaseline = firstLineBoxBaseline();

    if (firstLineBaseline != -1)

        return firstLineBaseline;

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

}

void RenderTableCell::styleWillChange(StyleDifference diff, const RenderStyle* newStyle)

{

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

        section()->setNeedsCellRecalc();

    ASSERT(newStyle->display() == TABLE_CELL);

    RenderBlock::styleWillChange(diff, newStyle);

}

void RenderTableCell::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)

{

    RenderBlock::styleDidChange(diff, oldStyle);

    setHasBoxDecorations(true);

}

// 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.

    int left = CSSPropertyBorderLeftColor;

    int right = CSSPropertyBorderRightColor;

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

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

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

    if (prevCell) {

        CollapsedBorderValue prevCellBorder = CollapsedBorderValue(&prevCell->style()->borderRight(), prevCell->style()->visitedDependentColor(right), BCELL);

        result = rtl ? compareBorders(result, prevCellBorder) : compareBorders(prevCellBorder, result);

        if (!result.exists())

            return result;

    } else if (leftmostColumn) {

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

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

        if (!result.exists())

            return result;

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

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

        if (!result.exists())

            return result;

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

            result = compareBorders(result, CollapsedBorderValue(&colElt->parent()->style()->borderLeft(), colElt->parent()->style()->visitedDependentColor(left), 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)) {

            CollapsedBorderValue rightBorder = CollapsedBorderValue(&colElt->style()->borderRight(), colElt->style()->visitedDependentColor(right), BCOL);

            result = rtl ? compareBorders(result, rightBorder) : compareBorders(rightBorder, result);

            if (!result.exists())

                return result;

        }

    } else {

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

        result = compareBorders(result, CollapsedBorderValue(&tableElt->style()->borderLeft(), tableElt->style()->visitedDependentColor(left), 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.

    int left = CSSPropertyBorderLeftColor;

    int right = CSSPropertyBorderRightColor;

    CollapsedBorderValue result = CollapsedBorderValue(&style()->borderRight(), style()->visitedDependentColor(right), 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()) {

            CollapsedBorderValue leftBorder = CollapsedBorderValue(&nextCell->style()->borderLeft(), nextCell->style()->visitedDependentColor(left), BCELL);

            result = rtl ? compareBorders(leftBorder, result) : compareBorders(result, leftBorder);

            if (!result.exists())

                return result;

        }

    } else {

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

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

        if (!result.exists())

            return result;

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

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

        if (!result.exists())

            return result;

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

            result = compareBorders(result, CollapsedBorderValue(&colElt->parent()->style()->borderRight(), colElt->parent()->style()->visitedDependentColor(right), 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)) {

            CollapsedBorderValue leftBorder = CollapsedBorderValue(&colElt->style()->borderLeft(), colElt->style()->visitedDependentColor(left), BCOL);

            result = rtl ? compareBorders(leftBorder, result) : compareBorders(result, leftBorder);

            if (!result.exists())

                return result;

        }

    } else {

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

        result = compareBorders(result, CollapsedBorderValue(&tableElt->style()->borderRight(), tableElt->style()->visitedDependentColor(right), 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.

    int top = CSSPropertyBorderTopColor;

    int bottom = CSSPropertyBorderBottomColor;

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

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

    if (prevCell) {

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

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

        if (!result.exists()) 

            return result;

    }

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

    result = compareBorders(result, CollapsedBorderValue(&parent()->style()->borderTop(), parent()->style()->visitedDependentColor(top), 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(CollapsedBorderValue(&prevRow->style()->borderBottom(), prevRow->style()->visitedDependentColor(bottom), BROW), result);

            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(), currSection->style()->visitedDependentColor(top), BROWGROUP));

        if (!result.exists())

            return result;

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

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

        if (currSection) {

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

            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(), colElt->style()->visitedDependentColor(top), BCOL));

            if (!result.exists())