autotablelayout.cpp

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        Length& width = m_layoutStruct[i].effWidth;
        switch (width.type()) {
        case Percent:
            havePercent = true;
            totalPercent += width.rawValue();
            break;
        case Relative:
            haveRelative = true;
            totalRelative += width.value();
            break;
        case Fixed:
            numFixed++;
            totalFixed += m_layoutStruct[i].effMaxWidth;
            // fall through
            break;
        case Auto:
        case Static:
            if (m_layoutStruct[i].emptyCellsOnly) 
                numAutoEmptyCellsOnly++;            
            else {
                numAuto++;
                totalAuto += m_layoutStruct[i].effMaxWidth;
                allocAuto += w;
            }
            break;
        default:
            break;
        }
    }

    // allocate width to percent cols
    if (available > 0 && havePercent) {
        for (int i = 0; i < nEffCols; i++) {
            Length &width = m_layoutStruct[i].effWidth;
            if (width.isPercent()) {
                int w = max(int(m_layoutStruct[i].effMinWidth), width.calcMinValue(tableWidth));
                available += m_layoutStruct[i].calcWidth - w;
                m_layoutStruct[i].calcWidth = w;
            }
        }
        if (totalPercent > 100 * percentScaleFactor) {
            // remove overallocated space from the last columns
            int excess = tableWidth*(totalPercent - 100 * percentScaleFactor) / (100 * percentScaleFactor);
            for (int i = nEffCols-1; i >= 0; i--) {
                if (m_layoutStruct[i].effWidth.isPercent()) {
                    int w = m_layoutStruct[i].calcWidth;
                    int reduction = min(w,  excess);
                    // the lines below might look inconsistent, but that's the way it's handled in mozilla
                    excess -= reduction;
                    int newWidth = max(int (m_layoutStruct[i].effMinWidth), w - reduction);
                    available += w - newWidth;
                    m_layoutStruct[i].calcWidth = newWidth;
                }
            }
        }
    }
    
    // then allocate width to fixed cols
    if (available > 0) {
        for (int i = 0; i < nEffCols; ++i) {
            Length &width = m_layoutStruct[i].effWidth;
            if (width.isFixed() && width.value() > m_layoutStruct[i].calcWidth) {
                available += m_layoutStruct[i].calcWidth - width.value();
                m_layoutStruct[i].calcWidth = width.value();
            }
        }
    }

    // now satisfy relative
    if (available > 0) {
        for (int i = 0; i < nEffCols; i++) {
            Length &width = m_layoutStruct[i].effWidth;
            if (width.isRelative() && width.value() != 0) {
                // width=0* gets effMinWidth.
                int w = width.value() * tableWidth / totalRelative;
                available += m_layoutStruct[i].calcWidth - w;
                m_layoutStruct[i].calcWidth = w;
            }
        }
    }

    // now satisfy variable
    if (available > 0 && numAuto) {
        available += allocAuto; // this gets redistributed
        for (int i = 0; i < nEffCols; i++) {
            Length &width = m_layoutStruct[i].effWidth;
            if (width.isAuto() && totalAuto != 0 && !m_layoutStruct[i].emptyCellsOnly) {
                int w = max(m_layoutStruct[i].calcWidth, static_cast<int>(available * static_cast<float>(m_layoutStruct[i].effMaxWidth) / totalAuto));
                available -= w;
                totalAuto -= m_layoutStruct[i].effMaxWidth;
                m_layoutStruct[i].calcWidth = w;
            }
        }
    }

    // spread over fixed columns
    if (available > 0 && numFixed) {
        // still have some width to spread, distribute to fixed columns
        for (int i = 0; i < nEffCols; i++) {
            Length &width = m_layoutStruct[i].effWidth;
            if (width.isFixed()) {
                int w = static_cast<int>(available * static_cast<float>(m_layoutStruct[i].effMaxWidth) / totalFixed);
                available -= w;
                totalFixed -= m_layoutStruct[i].effMaxWidth;
                m_layoutStruct[i].calcWidth += w;
            }
        }
    }

    // spread over percent colums
    if (available > 0 && m_hasPercent && totalPercent < 100 * percentScaleFactor) {
        // still have some width to spread, distribute weighted to percent columns
        for (int i = 0; i < nEffCols; i++) {
            Length &width = m_layoutStruct[i].effWidth;
            if (width.isPercent()) {
                int w = available * width.rawValue() / totalPercent;
                available -= w;
                totalPercent -= width.rawValue();
                m_layoutStruct[i].calcWidth += w;
                if (!available || !totalPercent) break;
            }
        }
    }

    // spread over the rest
    if (available > 0 && nEffCols > numAutoEmptyCellsOnly) {
        int total = nEffCols - numAutoEmptyCellsOnly;
        // still have some width to spread
        int i = nEffCols;
        while (i--) {
            // variable columns with empty cells only don't get any width
            if (m_layoutStruct[i].effWidth.isAuto() && m_layoutStruct[i].emptyCellsOnly)
                continue;
            int w = available / total;
            available -= w;
            total--;
            m_layoutStruct[i].calcWidth += w;
        }
    }

    // if we have overallocated, reduce every cell according to the difference between desired width and minwidth
    // this seems to produce to the pixel exaxt results with IE. Wonder is some of this also holds for width distributing.
    if (available < 0) {
        // Need to reduce cells with the following prioritization:
        // (1) Auto
        // (2) Relative
        // (3) Fixed
        // (4) Percent
        // This is basically the reverse of how we grew the cells.
        if (available < 0) {
            int mw = 0;
            for (int i = nEffCols-1; i >= 0; i--) {
                Length &width = m_layoutStruct[i].effWidth;
                if (width.isAuto())
                    mw += m_layoutStruct[i].calcWidth - m_layoutStruct[i].effMinWidth;
            }
            
            for (int i = nEffCols-1; i >= 0 && mw > 0; i--) {
                Length &width = m_layoutStruct[i].effWidth;
                if (width.isAuto()) {
                    int minMaxDiff = m_layoutStruct[i].calcWidth-m_layoutStruct[i].effMinWidth;
                    int reduce = available * minMaxDiff / mw;
                    m_layoutStruct[i].calcWidth += reduce;
                    available -= reduce;
                    mw -= minMaxDiff;
                    if (available >= 0)
                        break;
                }
            }
        }

        if (available < 0) {
            int mw = 0;
            for (int i = nEffCols-1; i >= 0; i--) {
                Length& width = m_layoutStruct[i].effWidth;
                if (width.isRelative())
                    mw += m_layoutStruct[i].calcWidth - m_layoutStruct[i].effMinWidth;
            }
            
            for (int i = nEffCols-1; i >= 0 && mw > 0; i--) {
                Length& width = m_layoutStruct[i].effWidth;
                if (width.isRelative()) {
                    int minMaxDiff = m_layoutStruct[i].calcWidth-m_layoutStruct[i].effMinWidth;
                    int reduce = available * minMaxDiff / mw;
                    m_layoutStruct[i].calcWidth += reduce;
                    available -= reduce;
                    mw -= minMaxDiff;
                    if (available >= 0)
                        break;
                }
            }
        }

        if (available < 0) {
            int mw = 0;
            for (int i = nEffCols-1; i >= 0; i--) {
                Length& width = m_layoutStruct[i].effWidth;
                if (width.isFixed())
                    mw += m_layoutStruct[i].calcWidth - m_layoutStruct[i].effMinWidth;
            }
            
            for (int i = nEffCols-1; i >= 0 && mw > 0; i--) {
                Length& width = m_layoutStruct[i].effWidth;
                if (width.isFixed()) {
                    int minMaxDiff = m_layoutStruct[i].calcWidth-m_layoutStruct[i].effMinWidth;
                    int reduce = available * minMaxDiff / mw;
                    m_layoutStruct[i].calcWidth += reduce;
                    available -= reduce;
                    mw -= minMaxDiff;
                    if (available >= 0)
                        break;
                }
            }
        }

        if (available < 0) {
            int mw = 0;
            for (int i = nEffCols-1; i >= 0; i--) {
                Length& width = m_layoutStruct[i].effWidth;
                if (width.isPercent())
                    mw += m_layoutStruct[i].calcWidth - m_layoutStruct[i].effMinWidth;
            }
            
            for (int i = nEffCols-1; i >= 0 && mw > 0; i--) {
                Length& width = m_layoutStruct[i].effWidth;
                if (width.isPercent()) {
                    int minMaxDiff = m_layoutStruct[i].calcWidth-m_layoutStruct[i].effMinWidth;
                    int reduce = available * minMaxDiff / mw;
                    m_layoutStruct[i].calcWidth += reduce;
                    available -= reduce;
                    mw -= minMaxDiff;
                    if (available >= 0)
                        break;
                }
            }
        }
    }

    int pos = 0;
    for (int i = 0; i < nEffCols; i++) {
        m_table->columnPositions()[i] = pos;
        pos += m_layoutStruct[i].calcWidth + m_table->hBorderSpacing();
    }
    m_table->columnPositions()[m_table->columnPositions().size() - 1] = pos;
}


void AutoTableLayout::calcPercentages() const
{
    unsigned totalPercent = 0;
    for (unsigned i = 0; i < m_layoutStruct.size(); i++) {
        if (m_layoutStruct[i].width.isPercent())
            totalPercent += m_layoutStruct[i].width.rawValue();
    }
    m_totalPercent = totalPercent / percentScaleFactor;
    m_percentagesDirty = false;
}

#undef DEBUG_LAYOUT

}