/*!
    \fn QString QTextList::itemText(const QTextBlock &block) const

    Returns the text of the list item that corresponds to the given \a block.
*/
QString QTextList::itemText(const QTextBlock &blockIt) const
{
    Q_D(const QTextList);
    int item = d->blocks.indexOf(blockIt) + 1;
    if (item <= 0)
        return QString();

    QTextBlock block = d->blocks.at(item-1);
    QTextBlockFormat blockFormat = block.blockFormat();

    QString result;

    const int style = format().style();
    QString numberPrefix;
    QString numberSuffix = QLatin1String(".");

    if (format().hasProperty(QTextFormat::ListNumberPrefix))
        numberPrefix = format().numberPrefix();
    if (format().hasProperty(QTextFormat::ListNumberSuffix))
        numberSuffix = format().numberSuffix();

    switch (style) {
        case QTextListFormat::ListDecimal:
            result = QString::number(item);
            break;
            // from the old richtext
        case QTextListFormat::ListLowerAlpha:
        case QTextListFormat::ListUpperAlpha:
            {
                const char baseChar = style == QTextListFormat::ListUpperAlpha ? 'A' : 'a';

                int c = item;
                while (c > 0) {
                    c--;
                    result.prepend(QChar(baseChar + (c % 26)));
                    c /= 26;
                }
            }
            break;
        case QTextListFormat::ListLowerRoman:
        case QTextListFormat::ListUpperRoman:
            {
                if (item < 5000) {
                    QByteArray romanNumeral;

                    // works for up to 4999 items
                    static const char romanSymbolsLower[] = "iiivixxxlxcccdcmmmm";
                    static const char romanSymbolsUpper[] = "IIIVIXXXLXCCCDCMMMM";
                    QByteArray romanSymbols; // wrap to have "mid"
                    if (style == QTextListFormat::ListLowerRoman)
                        romanSymbols = QByteArray::fromRawData(romanSymbolsLower, sizeof(romanSymbolsLower));
                    else
                        romanSymbols = QByteArray::fromRawData(romanSymbolsUpper, sizeof(romanSymbolsUpper));

                    int c[] = { 1, 4, 5, 9, 10, 40, 50, 90, 100, 400, 500, 900, 1000 };
                    int n = item;
                    for (int i = 12; i >= 0; n %= c[i], i--) {
                        int q = n / c[i];
                        if (q > 0) {
                            int startDigit = i + (i+3)/4;
                            int numDigits;
                            if (i % 4) {
                                // c[i] == 4|5|9|40|50|90|400|500|900
                                if ((i-2) % 4) {
                                    // c[i] == 4|9|40|90|400|900 => with subtraction (IV, IX, XL, XC, ...)
                                    numDigits = 2;
                                }
                                else {
                                    // c[i] == 5|50|500 (V, L, D)
                                    numDigits = 1;
                                }
                            }
                            else {
                                // c[i] == 1|10|100|1000 (I, II, III, X, XX, ...)
                                numDigits = q;
                            }

                            romanNumeral.append(romanSymbols.mid(startDigit, numDigits));
                        }
                    }
                    result = QString::fromLatin1(romanNumeral);
                }
                else {
                    result = QLatin1String("?");
                }

            }
            break;
        default:
            Q_ASSERT(false);
    }
    if (blockIt.textDirection() == Qt::RightToLeft)
        return numberSuffix + result + numberPrefix;
    else
        return numberPrefix + result + numberSuffix;
}
void QQuickTextNodeEngine::addTextBlock(QTextDocument *textDocument, const QTextBlock &block, const QPointF &position, const QColor &textColor, const QColor &anchorColor, int selectionStart, int selectionEnd)
{
    Q_ASSERT(textDocument);
#ifndef QT_NO_IM
    int preeditLength = block.isValid() ? block.layout()->preeditAreaText().length() : 0;
    int preeditPosition = block.isValid() ? block.layout()->preeditAreaPosition() : -1;
#endif

    QVarLengthArray<QTextLayout::FormatRange> colorChanges;
    mergeFormats(block.layout(), &colorChanges);

    QPointF blockPosition = textDocument->documentLayout()->blockBoundingRect(block).topLeft() + position;
    if (QTextList *textList = block.textList()) {
        QPointF pos = blockPosition;
        QTextLayout *layout = block.layout();
        if (layout->lineCount() > 0) {
            QTextLine firstLine = layout->lineAt(0);
            Q_ASSERT(firstLine.isValid());

            setCurrentLine(firstLine);

            QRectF textRect = firstLine.naturalTextRect();
            pos += textRect.topLeft();
            if (block.textDirection() == Qt::RightToLeft)
                pos.rx() += textRect.width();

            const QTextCharFormat charFormat = block.charFormat();
            QFont font(charFormat.font());
            QFontMetricsF fontMetrics(font);
            QTextListFormat listFormat = textList->format();

            QString listItemBullet;
            switch (listFormat.style()) {
            case QTextListFormat::ListCircle:
                listItemBullet = QChar(0x25E6); // White bullet
                break;
            case QTextListFormat::ListSquare:
                listItemBullet = QChar(0x25AA); // Black small square
                break;
            case QTextListFormat::ListDecimal:
            case QTextListFormat::ListLowerAlpha:
            case QTextListFormat::ListUpperAlpha:
            case QTextListFormat::ListLowerRoman:
            case QTextListFormat::ListUpperRoman:
                listItemBullet = textList->itemText(block);
                break;
            default:
                listItemBullet = QChar(0x2022); // Black bullet
                break;
            };

            QSizeF size(fontMetrics.width(listItemBullet), fontMetrics.height());
            qreal xoff = fontMetrics.width(QLatin1Char(' '));
            if (block.textDirection() == Qt::LeftToRight)
                xoff = -xoff - size.width();
            setPosition(pos + QPointF(xoff, 0));

            QTextLayout layout;
            layout.setFont(font);
            layout.setText(listItemBullet); // Bullet
            layout.beginLayout();
            QTextLine line = layout.createLine();
            line.setPosition(QPointF(0, 0));
            layout.endLayout();

            QList<QGlyphRun> glyphRuns = layout.glyphRuns();
            for (int i=0; i<glyphRuns.size(); ++i)
                addUnselectedGlyphs(glyphRuns.at(i));
        }
    }

    int textPos = block.position();
    QTextBlock::iterator blockIterator = block.begin();

    while (!blockIterator.atEnd()) {
        QTextFragment fragment = blockIterator.fragment();
        QString text = fragment.text();
        if (text.isEmpty())
            continue;

        QTextCharFormat charFormat = fragment.charFormat();
        QFont font(charFormat.font());
        QFontMetricsF fontMetrics(font);

        int fontHeight = fontMetrics.descent() + fontMetrics.ascent();
        int valign = charFormat.verticalAlignment();
        if (valign == QTextCharFormat::AlignSuperScript)
            setPosition(QPointF(blockPosition.x(), blockPosition.y() - fontHeight / 2));
        else if (valign == QTextCharFormat::AlignSubScript)
            setPosition(QPointF(blockPosition.x(), blockPosition.y() + fontHeight / 6));
        else
            setPosition(blockPosition);

        if (text.contains(QChar::ObjectReplacementCharacter)) {
            QTextFrame *frame = qobject_cast<QTextFrame *>(textDocument->objectForFormat(charFormat));
            if (frame && frame->frameFormat().position() == QTextFrameFormat::InFlow) {
                int blockRelativePosition = textPos - block.position();
                QTextLine line = block.layout()->lineForTextPosition(blockRelativePosition);
                if (!currentLine().isValid()
                        || line.lineNumber() != currentLine().lineNumber()) {
                    setCurrentLine(line);
                }

                QQuickTextNodeEngine::SelectionState selectionState =
                        (selectionStart < textPos + text.length()
                         && selectionEnd >= textPos)
                        ? QQuickTextNodeEngine::Selected
                        : QQuickTextNodeEngine::Unselected;

                addTextObject(QPointF(), charFormat, selectionState, textDocument, textPos);
            }
            textPos += text.length();
        } else {
            if (charFormat.foreground().style() != Qt::NoBrush)
                setTextColor(charFormat.foreground().color());
            else if (charFormat.isAnchor())
                setTextColor(anchorColor);
            else
                setTextColor(textColor);

            int fragmentEnd = textPos + fragment.length();
#ifndef QT_NO_IM
            if (preeditPosition >= 0
                    && (preeditPosition + block.position()) >= textPos
                    && (preeditPosition + block.position()) <= fragmentEnd) {
                fragmentEnd += preeditLength;
            }
#endif
            if (charFormat.background().style() != Qt::NoBrush) {
                QTextLayout::FormatRange additionalFormat;
                additionalFormat.start = textPos - block.position();
                additionalFormat.length = fragmentEnd - textPos;
                additionalFormat.format = charFormat;
                colorChanges << additionalFormat;
            }

            textPos = addText(block, charFormat, textColor, colorChanges, textPos, fragmentEnd,
                                                 selectionStart, selectionEnd);
        }

        ++blockIterator;
    }

#ifndef QT_NO_IM
    if (preeditLength >= 0 && textPos <= block.position() + preeditPosition) {
        setPosition(blockPosition);
        textPos = block.position() + preeditPosition;
        QTextLine line = block.layout()->lineForTextPosition(preeditPosition);
        if (!currentLine().isValid()
                || line.lineNumber() != currentLine().lineNumber()) {
            setCurrentLine(line);
        }
        textPos = addText(block, block.charFormat(), textColor, colorChanges,
                                             textPos, textPos + preeditLength,
                                             selectionStart, selectionEnd);
    }
#endif

    setCurrentLine(QTextLine()); // Reset current line because the text layout changed
    m_hasContents = true;
}