path: root/src/declarative/graphicsitems/qdeclarativetext.cpp

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#include "private/qdeclarativetext_p.h"
#include "private/qdeclarativetext_p_p.h"
#include <private/qtextdocumentlayout_p.h>
#include <qdeclarativestyledtext_p.h>
#include <qdeclarativeinfo.h>
#include <qdeclarativepixmapcache_p.h>

#include <QSet>
#include <QTextLayout>
#include <QTextLine>
#include <QTextDocument>
#include <QTextCursor>
#include <QGraphicsSceneMouseEvent>
#include <QPainter>
#include <QAbstractTextDocumentLayout>
#include <qmath.h>
#include <limits.h>

QT_BEGIN_NAMESPACE

extern Q_GUI_EXPORT bool qt_applefontsmoothing_enabled;

class QTextDocumentWithImageResources : public QTextDocument {
    Q_OBJECT

public:
    QTextDocumentWithImageResources(QDeclarativeText *parent);
    virtual ~QTextDocumentWithImageResources();

    void setText(const QString &);
    int resourcesLoading() const { return outstanding; }

protected:
    QVariant loadResource(int type, const QUrl &name);

private slots:
    void requestFinished();

private:
    QHash<QUrl, QDeclarativePixmap *> m_resources;

    int outstanding;
    static QSet<QUrl> errors;
};

class QDeclarativeTextDocumentLayout : public QTextDocumentLayout
{
    Q_OBJECT
public:
    QDeclarativeTextDocumentLayout(QTextDocument *doc);
    void setLineHeight(qreal lineHeight, QDeclarativeText::LineHeightMode mode);
};

DEFINE_BOOL_CONFIG_OPTION(enableImageCache, QML_ENABLE_TEXT_IMAGE_CACHE);

QString QDeclarativeTextPrivate::elideChar = QString(0x2026);

QDeclarativeTextPrivate::QDeclarativeTextPrivate()
: color((QRgb)0), style(QDeclarativeText::Normal), hAlign(QDeclarativeText::AlignLeft), 
  vAlign(QDeclarativeText::AlignTop), elideMode(QDeclarativeText::ElideNone),
  format(QDeclarativeText::AutoText), wrapMode(QDeclarativeText::NoWrap), lineHeight(1), lineHeightMode(QDeclarativeText::MultiplyHeight),
  lineCount(1), truncated(false), maximumLineCount(INT_MAX),
  maximumLineCountValid(false), imageCacheDirty(true), updateOnComponentComplete(true), richText(false), singleline(false),
  cacheAllTextAsImage(true), internalWidthUpdate(false), requireImplicitWidth(false), naturalWidth(0), doc(0)
{
    cacheAllTextAsImage = enableImageCache();
    QGraphicsItemPrivate::acceptedMouseButtons = Qt::LeftButton;
    QGraphicsItemPrivate::flags = QGraphicsItemPrivate::flags & ~QGraphicsItem::ItemHasNoContents;
}

QTextDocumentWithImageResources::QTextDocumentWithImageResources(QDeclarativeText *parent) 
: QTextDocument(parent), outstanding(0)
{
}

QTextDocumentWithImageResources::~QTextDocumentWithImageResources()
{
    if (!m_resources.isEmpty()) 
        qDeleteAll(m_resources);
}

QVariant QTextDocumentWithImageResources::loadResource(int type, const QUrl &name)
{
    QDeclarativeContext *context = qmlContext(parent());
    QUrl url = context->resolvedUrl(name);

    if (type == QTextDocument::ImageResource) {
        QHash<QUrl, QDeclarativePixmap *>::Iterator iter = m_resources.find(url);

        if (iter == m_resources.end()) {
            QDeclarativePixmap *p = new QDeclarativePixmap(context->engine(), url);
            iter = m_resources.insert(name, p);

            if (p->isLoading()) {
                p->connectFinished(this, SLOT(requestFinished()));
                outstanding++;
            }
        }

        QDeclarativePixmap *p = *iter;
        if (p->isReady()) {
            return p->pixmap();
        } else if (p->isError()) {
            if (!errors.contains(url)) {
                errors.insert(url);
                qmlInfo(parent()) << p->error();
            }
        }
    }

    return QTextDocument::loadResource(type,url); // The *resolved* URL
}

void QTextDocumentWithImageResources::requestFinished()
{
    outstanding--;
    if (outstanding == 0) {
        QDeclarativeText *textItem = static_cast<QDeclarativeText*>(parent());
        QString text = textItem->text();
#ifndef QT_NO_TEXTHTMLPARSER
        setHtml(text);
#else
        setPlainText(text);
#endif
        QDeclarativeTextPrivate *d = QDeclarativeTextPrivate::get(textItem);
        d->updateLayout();
    }
}

void QTextDocumentWithImageResources::setText(const QString &text)
{
    if (!m_resources.isEmpty()) {
        qDeleteAll(m_resources);
        m_resources.clear();
        outstanding = 0;
    }

#ifndef QT_NO_TEXTHTMLPARSER
    setHtml(text);
#else
    setPlainText(text);
#endif
}

QSet<QUrl> QTextDocumentWithImageResources::errors;

QDeclarativeTextDocumentLayout::QDeclarativeTextDocumentLayout(QTextDocument *doc)
    : QTextDocumentLayout(doc) {
}

void QDeclarativeTextDocumentLayout::setLineHeight(qreal lineHeight, QDeclarativeText::LineHeightMode mode = QDeclarativeText::MultiplyHeight)
{
    QTextDocumentLayout::setLineHeight(lineHeight, QTextDocumentLayout::LineHeightMode(mode));
}

QDeclarativeTextPrivate::~QDeclarativeTextPrivate()
{
}

qreal QDeclarativeTextPrivate::implicitWidth() const
{
    if (!requireImplicitWidth) {
        // We don't calculate implicitWidth unless it is required.
        // We need to force a size update now to ensure implicitWidth is calculated
        QDeclarativeTextPrivate *me = const_cast<QDeclarativeTextPrivate*>(this);
        me->requireImplicitWidth = true;
        me->updateSize();
    }
    return mImplicitWidth;
}

void QDeclarativeTextPrivate::updateLayout()
{
    Q_Q(QDeclarativeText);
    if (!q->isComponentComplete()) {
        updateOnComponentComplete = true;
        return;
    }

    // Setup instance of QTextLayout for all cases other than richtext
    if (!richText) {
        layout.clearLayout();
        layout.setFont(font);
        if (format != QDeclarativeText::StyledText) {
            QString tmp = text;
            tmp.replace(QLatin1Char('\n'), QChar::LineSeparator);
            singleline = !tmp.contains(QChar::LineSeparator);
            if (singleline && !maximumLineCountValid && elideMode != QDeclarativeText::ElideNone && q->widthValid()) {
                QFontMetrics fm(font);
                tmp = fm.elidedText(tmp,(Qt::TextElideMode)elideMode,q->width()); // XXX still worth layout...?
                if (tmp != text && !truncated) {
                    truncated = true;
                    emit q->truncatedChanged();
                }
            }
            layout.setText(tmp);
        } else {
            singleline = false;
            QDeclarativeStyledText::parse(text, layout);
        }
    } else {
        ensureDoc();
        QDeclarativeTextDocumentLayout *layout = new QDeclarativeTextDocumentLayout(doc);
        layout->setLineHeight(lineHeight, lineHeightMode);
        doc->setDocumentLayout(layout);
    }

    updateSize();
}

void QDeclarativeTextPrivate::updateSize()
{
    Q_Q(QDeclarativeText);

    if (!q->isComponentComplete()) {
        updateOnComponentComplete = true;
        return;
    }

    if (!requireImplicitWidth) {
        emit q->implicitWidthChanged();
        // if the implicitWidth is used, then updateSize() has already been called (recursively)
        if (requireImplicitWidth)
            return;
    }

    invalidateImageCache();

    QFontMetrics fm(font);
    if (text.isEmpty()) {
        q->setImplicitWidth(0);
        q->setImplicitHeight(fm.height());
        paintedSize = QSize(0, fm.height());
        emit q->paintedSizeChanged();
        q->update();
        return;
    }

    int dy = q->height();
    QSize size(0, 0);

    //setup instance of QTextLayout for all cases other than richtext
    if (!richText) {
        size = setupTextLayout();
        if (layedOutTextSize != size) {
            q->prepareGeometryChange();
            layedOutTextSize = size;
        }
        dy -= size.height();
    } else {
        singleline = false; // richtext can't elide or be optimized for single-line case
        ensureDoc();
        doc->setDefaultFont(font);
        QTextOption option;
        option.setAlignment((Qt::Alignment)int(hAlign | vAlign));
        option.setWrapMode(QTextOption::WrapMode(wrapMode));
        doc->setDefaultTextOption(option);
        if (requireImplicitWidth && q->widthValid()) {
            doc->setTextWidth(-1);
            naturalWidth = doc->idealWidth();
        }
        if (wrapMode != QDeclarativeText::NoWrap && q->widthValid())
            doc->setTextWidth(q->width());
        else
            doc->setTextWidth(doc->idealWidth()); // ### Text does not align if width is not set (QTextDoc bug)
        dy -= (int)doc->size().height();
        QSize dsize = doc->size().toSize();
        if (dsize != layedOutTextSize) {
            q->prepareGeometryChange();
            layedOutTextSize = dsize;
        }
        size = QSize(int(doc->idealWidth()),dsize.height());
    }
    int yoff = 0;

    if (q->heightValid()) {
        if (vAlign == QDeclarativeText::AlignBottom)
            yoff = dy;
        else if (vAlign == QDeclarativeText::AlignVCenter)
            yoff = dy/2;
    }
    q->setBaselineOffset(fm.ascent() + yoff);

    //### need to comfirm cost of always setting these for richText
    internalWidthUpdate = true;
    if (!q->widthValid())
        q->setImplicitWidth(size.width());
    else if (requireImplicitWidth)
        q->setImplicitWidth(naturalWidth);
    internalWidthUpdate = false;
    q->setImplicitHeight(size.height());
    if (paintedSize != size) {
        paintedSize = size;
        emit q->paintedSizeChanged();
    }
    q->update();
}

/*!
    Lays out the QDeclarativeTextPrivate::layout QTextLayout in the constraints of the QDeclarativeText.

    Returns the size of the final text.  This can be used to position the text vertically (the text is
    already absolutely positioned horizontally).
*/
QSize QDeclarativeTextPrivate::setupTextLayout()
{
    // ### text layout handling should be profiled and optimized as needed
    // what about QStackTextEngine engine(tmp, d->font.font()); QTextLayout textLayout(&engine);
    Q_Q(QDeclarativeText);
    layout.setCacheEnabled(true);

    qreal height = 0;
    qreal widthUsed = 0;
    qreal lineWidth = 0;
    int visibleTextLength = 0;
    int visibleCount = 0;

    //set manual width
    if ((wrapMode != QDeclarativeText::NoWrap || elideMode != QDeclarativeText::ElideNone) && q->widthValid())
        lineWidth = q->width();

    QTextOption textOption = layout.textOption();
    if (hAlign == QDeclarativeText::AlignJustify)
        textOption.setAlignment(Qt::Alignment(hAlign));
    textOption.setWrapMode(QTextOption::WrapMode(wrapMode));
    layout.setTextOption(textOption);

    QDeclarativeText::HAlignment hAlignment = hAlign;
    if(text.isRightToLeft()) {
        if ((hAlign == QDeclarativeText::AlignLeft) || (hAlign == QDeclarativeText::AlignJustify)) {
            hAlignment = QDeclarativeText::AlignRight;
        } else if (hAlign == QDeclarativeText::AlignRight) {
            hAlignment = QDeclarativeText::AlignLeft;
        } else {
            hAlignment = hAlign;
        }
    }

    bool elideText = false;
    bool truncate = false;

    QFontMetrics fm(layout.font());
    qreal elideWidth = fm.width(elideChar);
    elidePos = QPointF();

    if (requireImplicitWidth && q->widthValid()) {
        // requires an extra layout
        layout.beginLayout();
        forever {
            QTextLine line = layout.createLine();
            if (!line.isValid())
                break;
        }
        layout.endLayout();
        naturalWidth = 0;
        for (int i = 0; i < layout.lineCount(); ++i) {
            QTextLine line = layout.lineAt(i);
            naturalWidth = qMax(naturalWidth, line.naturalTextWidth());
        }
    }

    if (maximumLineCountValid) {
        layout.beginLayout();
        if (!lineWidth)
            lineWidth = INT_MAX;
        int y = 0;
        int linesLeft = maximumLineCount;
        while (linesLeft > 0) {
            QTextLine line = layout.createLine();
            if (!line.isValid())
                break;

            visibleCount++;
            line.setLineWidth(lineWidth);
            visibleTextLength += line.textLength();

            if (--linesLeft == 0) {
                if (visibleTextLength < text.length()) {
                    truncate = true;
                    if (elideMode==QDeclarativeText::ElideRight && q->widthValid()) {
                        // Need to correct for alignment
                        line.setLineWidth(lineWidth-elideWidth);
                        int x = line.naturalTextWidth();
                        if (hAlignment == QDeclarativeText::AlignRight) {
                            x = q->width()-elideWidth;
                        } else if (hAlignment == QDeclarativeText::AlignHCenter) {
                            x = (q->width()+line.naturalTextWidth()-elideWidth)/2;
                        }
                        elidePos = QPointF(x, y + fm.ascent());
                        elideText = true;
                    }
                }
            }

            y += line.height();
        }
        layout.endLayout();

        //Update truncated
        if (truncated != truncate) {
            truncated = truncate;
            emit q->truncatedChanged();
        }
    } else {
        layout.beginLayout();
        forever {
            QTextLine line = layout.createLine();
            if (!line.isValid())
                break;
            visibleCount++;
            if (lineWidth)
                line.setLineWidth(lineWidth);
        }
        layout.endLayout();
    }

    for (int i = 0; i < layout.lineCount(); ++i) {
        QTextLine line = layout.lineAt(i);
        widthUsed = qMax(widthUsed, line.naturalTextWidth());
    }

    qreal layoutWidth = q->widthValid() ? q->width() : widthUsed;
    if (!q->widthValid())
        naturalWidth = layoutWidth;

    qreal x = 0;
    for (int i = 0; i < layout.lineCount(); ++i) {
        QTextLine line = layout.lineAt(i);
        line.setPosition(QPointF(0, height));
        height += (lineHeightMode == QDeclarativeText::PixelHeight) ? lineHeight : line.height() * lineHeight;

        if (!cacheAllTextAsImage) {
            if ((hAlignment == QDeclarativeText::AlignLeft) || (hAlignment == QDeclarativeText::AlignJustify)) {
                x = 0;
            } else if (hAlignment == QDeclarativeText::AlignRight) {
                x = layoutWidth - line.naturalTextWidth();
                if (elideText && i == layout.lineCount()-1)
                    x -= elideWidth; // Correct for when eliding multilines
            } else if (hAlignment == QDeclarativeText::AlignHCenter) {
                x = (layoutWidth - line.naturalTextWidth()) / 2;
                if (elideText && i == layout.lineCount()-1)
                    x -= elideWidth/2; // Correct for when eliding multilines
            }
            line.setPosition(QPointF(x, line.y()));
        }
    }

    //Update the number of visible lines
    if (lineCount != visibleCount) {
        lineCount = visibleCount;
        emit q->lineCountChanged();
    }

    return QSize(qCeil(widthUsed), qCeil(height));
}

/*!
    Returns a painted version of the QDeclarativeTextPrivate::layout QTextLayout.
    If \a drawStyle is true, the style color overrides all colors in the document.
*/
QPixmap QDeclarativeTextPrivate::textLayoutImage(bool drawStyle)
{
    //do layout
    QSize size = layedOutTextSize;

    qreal x = 0;
    for (int i = 0; i < layout.lineCount(); ++i) {
        QTextLine line = layout.lineAt(i);
        if ((hAlign == QDeclarativeText::AlignLeft) || (hAlign == QDeclarativeText::AlignJustify)) {
            x = 0;
        } else if (hAlign == QDeclarativeText::AlignRight) {
            x = size.width() - line.naturalTextWidth();
        } else if (hAlign == QDeclarativeText::AlignHCenter) {
            x = (size.width() - line.naturalTextWidth()) / 2;
        }
        line.setPosition(QPointF(x, line.y()));
    }

    //paint text
    QPixmap img(size);
    if (!size.isEmpty()) {
        img.fill(Qt::transparent);
#ifdef Q_WS_MAC
        bool oldSmooth = qt_applefontsmoothing_enabled;
        qt_applefontsmoothing_enabled = false;
#endif
        QPainter p(&img);
#ifdef Q_WS_MAC
        qt_applefontsmoothing_enabled = oldSmooth;
#endif
        drawTextLayout(&p, QPointF(0,0), drawStyle);
    }
    return img;
}

/*!
    Paints the QDeclarativeTextPrivate::layout QTextLayout into \a painter at \a pos.  If 
    \a drawStyle is true, the style color overrides all colors in the document.
*/
void QDeclarativeTextPrivate::drawTextLayout(QPainter *painter, const QPointF &pos, bool drawStyle)
{
    if (drawStyle)
        painter->setPen(styleColor);
    else
        painter->setPen(color);
    painter->setFont(font);
    layout.draw(painter, pos);
    if (!elidePos.isNull())
        painter->drawText(elidePos, elideChar);
}

/*!
    Returns a painted version of the QDeclarativeTextPrivate::doc QTextDocument.
    If \a drawStyle is true, the style color overrides all colors in the document.
*/
QPixmap QDeclarativeTextPrivate::textDocumentImage(bool drawStyle)
{
    QSize size = doc->size().toSize();

    //paint text
    QPixmap img(size);
    img.fill(Qt::transparent);
#ifdef Q_WS_MAC
    bool oldSmooth = qt_applefontsmoothing_enabled;
    qt_applefontsmoothing_enabled = false;
#endif
    QPainter p(&img);
#ifdef Q_WS_MAC
    qt_applefontsmoothing_enabled = oldSmooth;
#endif

    QAbstractTextDocumentLayout::PaintContext context;

    QTextOption oldOption(doc->defaultTextOption());
    if (drawStyle) {
        context.palette.setColor(QPalette::Text, styleColor);
        QTextOption colorOption(doc->defaultTextOption());
        colorOption.setFlags(QTextOption::SuppressColors);
        doc->setDefaultTextOption(colorOption);
    } else {
        context.palette.setColor(QPalette::Text, color);
    }
    doc->documentLayout()->draw(&p, context);
    if (drawStyle)
        doc->setDefaultTextOption(oldOption);
    return img;
}

/*!
    Mark the image cache as dirty.
*/
void QDeclarativeTextPrivate::invalidateImageCache() 
{
    Q_Q(QDeclarativeText);

    if(cacheAllTextAsImage || style != QDeclarativeText::Normal){//If actually using the image cache
        if (imageCacheDirty)
            return;

        imageCacheDirty = true;
        imageCache = QPixmap();
    }
    if (q->isComponentComplete())
        q->update();
}

/*!
    Tests if the image cache is dirty, and repaints it if it is.
*/
void QDeclarativeTextPrivate::checkImageCache()
{
    if (!imageCacheDirty)
        return;

    if (text.isEmpty()) {

        imageCache = QPixmap();

    } else {

        QPixmap textImage;
        QPixmap styledImage;

        if (richText) {
            textImage = textDocumentImage(false);
            if (style != QDeclarativeText::Normal)
                styledImage = textDocumentImage(true); //### should use styleColor
        } else {
            textImage = textLayoutImage(false);
            if (style != QDeclarativeText::Normal)
                styledImage = textLayoutImage(true); //### should use styleColor
        }

        switch (style) {
        case QDeclarativeText::Outline:
            imageCache = drawOutline(textImage, styledImage);
            break;
        case QDeclarativeText::Sunken:
            imageCache = drawOutline(textImage, styledImage, -1);
            break;
        case QDeclarativeText::Raised:
            imageCache = drawOutline(textImage, styledImage, 1);
            break;
        default:
            imageCache = textImage;
            break;
        }

    } 

    imageCacheDirty = false;
}

/*! 
    Ensures the QDeclarativeTextPrivate::doc variable is set to a valid text document 
*/
void QDeclarativeTextPrivate::ensureDoc()
{
    if (!doc) {
        Q_Q(QDeclarativeText);
        doc = new QTextDocumentWithImageResources(q);
        doc->setDocumentMargin(0);
    }
}

/*!
    Draw \a styleSource as an outline around \a source and return the new image.
*/
QPixmap QDeclarativeTextPrivate::drawOutline(const QPixmap &source, const QPixmap &styleSource)
{
    QPixmap img = QPixmap(styleSource.width() + 2, styleSource.height() + 2);
    img.fill(Qt::transparent);

    QPainter ppm(&img);

    QPoint pos(0, 0);
    pos += QPoint(-1, 0);
    ppm.drawPixmap(pos, styleSource);
    pos += QPoint(2, 0);
    ppm.drawPixmap(pos, styleSource);
    pos += QPoint(-1, -1);
    ppm.drawPixmap(pos, styleSource);
    pos += QPoint(0, 2);
    ppm.drawPixmap(pos, styleSource);

    pos += QPoint(0, -1);
    ppm.drawPixmap(pos, source);
    ppm.end();

    return img;
}

/*!
    Draw \a styleSource below \a source at \a yOffset and return the new image.
*/
QPixmap QDeclarativeTextPrivate::drawOutline(const QPixmap &source, const QPixmap &styleSource, int yOffset)
{
    QPixmap img = QPixmap(styleSource.width() + 2, styleSource.height() + 2);
    img.fill(Qt::transparent);

    QPainter ppm(&img);

    ppm.drawPixmap(QPoint(0, yOffset), styleSource);
    ppm.drawPixmap(0, 0, source);

    ppm.end();

    return img;
}

/*!
    \qmlclass Text QDeclarativeText
    \ingroup qml-basic-visual-elements
    \since 4.7
    \brief The Text item allows you to add formatted text to a scene.
    \inherits Item

    A Text item can display both plain and rich text. For example:

    \qml
    Text { text: "Hello World!"; font.family: "Helvetica"; font.pointSize: 24; color: "red" }
    Text { text: "<b>Hello</b> <i>World!</i>" }
    \endqml

    \image declarative-text.png

    If height and width are not explicitly set, Text will attempt to determine how
    much room is needed and set it accordingly. Unless \l wrapMode is set, it will always
    prefer width to height (all text will be placed on a single line).

    The \l elide property can alternatively be used to fit a single line of
    plain text to a set width.

    Note that the \l{Supported HTML Subset} is limited. Also, if the text contains
    HTML img tags that load remote images, the text is reloaded.

    Text provides read-only text. For editable text, see \l TextEdit.

    \sa {declarative/text/fonts}{Fonts example}
*/
QDeclarativeText::QDeclarativeText(QDeclarativeItem *parent)
  : QDeclarativeImplicitSizeItem(*(new QDeclarativeTextPrivate), parent)
{
}

QDeclarativeText::~QDeclarativeText()
{
}

/*!
  \qmlproperty bool Text::clip
  This property holds whether the text is clipped.

  Note that if the text does not fit in the bounding rectangle it will be abruptly chopped.

  If you want to display potentially long text in a limited space, you probably want to use \c elide instead.
*/

/*!
    \qmlproperty bool Text::smooth

    This property holds whether the text is smoothly scaled or transformed.

    Smooth filtering gives better visual quality, but is slower.  If
    the item is displayed at its natural size, this property has no visual or
    performance effect.

    \note Generally scaling artifacts are only visible if the item is stationary on
    the screen.  A common pattern when animating an item is to disable smooth
    filtering at the beginning of the animation and reenable it at the conclusion.
*/

/*!
    \qmlsignal Text::onLinkActivated(string link)

    This handler is called when the user clicks on a link embedded in the text.
    The link must be in rich text or HTML format and the 
    \a link string provides access to the particular link. 

    \snippet doc/src/snippets/declarative/text/onLinkActivated.qml 0

    The example code will display the text 
    "The main website is at \l{http://qt.nokia.com}{Nokia Qt DF}."

    Clicking on the highlighted link will output 
    \tt{http://qt.nokia.com link activated} to the console.
*/

/*!
    \qmlproperty string Text::font.family

    Sets the family name of the font.

    The family name is case insensitive and may optionally include a foundry name, e.g. "Helvetica [Cronyx]".
    If the family is available from more than one foundry and the foundry isn't specified, an arbitrary foundry is chosen.
    If the family isn't available a family will be set using the font matching algorithm.
*/

/*!
    \qmlproperty bool Text::font.bold

    Sets whether the font weight is bold.
*/

/*!
    \qmlproperty enumeration Text::font.weight

    Sets the font's weight.

    The weight can be one of:
    \list
    \o Font.Light
    \o Font.Normal - the default
    \o Font.DemiBold
    \o Font.Bold
    \o Font.Black
    \endlist

    \qml
    Text { text: "Hello"; font.weight: Font.DemiBold }
    \endqml
*/

/*!
    \qmlproperty bool Text::font.italic

    Sets whether the font has an italic style.
*/

/*!
    \qmlproperty bool Text::font.underline

    Sets whether the text is underlined.
*/

/*!
    \qmlproperty bool Text::font.strikeout

    Sets whether the font has a strikeout style.
*/

/*!
    \qmlproperty real Text::font.pointSize

    Sets the font size in points. The point size must be greater than zero.
*/

/*!
    \qmlproperty int Text::font.pixelSize

    Sets the font size in pixels.

    Using this function makes the font device dependent.
    Use \c pointSize to set the size of the font in a device independent manner.
*/

/*!
    \qmlproperty real Text::font.letterSpacing

    Sets the letter spacing for the font.

    Letter spacing changes the default spacing between individual letters in the font.
    A positive value increases the letter spacing by the corresponding pixels; a negative value decreases the spacing.
*/

/*!
    \qmlproperty real Text::font.wordSpacing

    Sets the word spacing for the font.

    Word spacing changes the default spacing between individual words.
    A positive value increases the word spacing by a corresponding amount of pixels,
    while a negative value decreases the inter-word spacing accordingly.
*/

/*!
    \qmlproperty enumeration Text::font.capitalization

    Sets the capitalization for the text.

    \list
    \o Font.MixedCase - This is the normal text rendering option where no capitalization change is applied.
    \o Font.AllUppercase - This alters the text to be rendered in all uppercase type.
    \o Font.AllLowercase	 - This alters the text to be rendered in all lowercase type.
    \o Font.SmallCaps -	This alters the text to be rendered in small-caps type.
    \o Font.Capitalize - This alters the text to be rendered with the first character of each word as an uppercase character.
    \endlist

    \qml
    Text { text: "Hello"; font.capitalization: Font.AllLowercase }
    \endqml
*/
QFont QDeclarativeText::font() const
{
    Q_D(const QDeclarativeText);
    return d->sourceFont;
}

void QDeclarativeText::setFont(const QFont &font)
{
    Q_D(QDeclarativeText);
    if (d->sourceFont == font)
        return;

    d->sourceFont = font;
    QFont oldFont = d->font;
    d->font = font;
    if (d->font.pointSizeF() != -1) {
        // 0.5pt resolution
        qreal size = qRound(d->font.pointSizeF()*2.0);
        d->font.setPointSizeF(size/2.0);
    }

    if (oldFont != d->font)
        d->updateLayout();

    emit fontChanged(d->sourceFont);
}

/*!
    \qmlproperty string Text::text

    The text to display. Text supports both plain and rich text strings.

    The item will try to automatically determine whether the text should
    be treated as rich text. This determination is made using Qt::mightBeRichText().
*/
QString QDeclarativeText::text() const
{
    Q_D(const QDeclarativeText);
    return d->text;
}

void QDeclarativeText::setText(const QString &n)
{
    Q_D(QDeclarativeText);
    if (d->text == n)
        return;

    d->richText = d->format == RichText || (d->format == AutoText && Qt::mightBeRichText(n));
    if (d->richText && isComponentComplete()) {
        d->ensureDoc();
        d->doc->setText(n);
    }

    d->text = n;
    d->updateLayout();

    emit textChanged(d->text);
}


/*!
    \qmlproperty color Text::color

    The text color.

    \qml
    //green text using hexadecimal notation
    Text { color: "#00FF00"; ... }

    //steelblue text using SVG color name
    Text { color: "steelblue"; ... }
    \endqml
*/
QColor QDeclarativeText::color() const
{
    Q_D(const QDeclarativeText);
    return d->color;
}

void QDeclarativeText::setColor(const QColor &color)
{
    Q_D(QDeclarativeText);
    if (d->color == color)
        return;

    d->color = color;
    d->invalidateImageCache();
    emit colorChanged(d->color);
}

/*!
    \qmlproperty enumeration Text::style

    Set an additional text style.

    Supported text styles are:
    \list
    \o Text.Normal - the default
    \o Text.Outline
    \o Text.Raised
    \o Text.Sunken
    \endlist

    \qml
    Row {
        Text { font.pointSize: 24; text: "Normal" }
        Text { font.pointSize: 24; text: "Raised"; style: Text.Raised; styleColor: "#AAAAAA" }
        Text { font.pointSize: 24; text: "Outline";style: Text.Outline; styleColor: "red" }
        Text { font.pointSize: 24; text: "Sunken"; style: Text.Sunken; styleColor: "#AAAAAA" }
    }
    \endqml

    \image declarative-textstyle.png
*/
QDeclarativeText::TextStyle QDeclarativeText::style() const
{
    Q_D(const QDeclarativeText);
    return d->style;
}

void QDeclarativeText::setStyle(QDeclarativeText::TextStyle style)
{
    Q_D(QDeclarativeText);
    if (d->style == style)
        return;

    // changing to/from Normal requires the boundingRect() to change
    if (isComponentComplete() && (d->style == Normal || style == Normal))
        prepareGeometryChange();
    d->style = style;
    d->invalidateImageCache();
    emit styleChanged(d->style);
}

/*!
    \qmlproperty color Text::styleColor

    Defines the secondary color used by text styles.

    \c styleColor is used as the outline color for outlined text, and as the
    shadow color for raised or sunken text. If no style has been set, it is not
    used at all.

    \qml
    Text { font.pointSize: 18; text: "hello"; style: Text.Raised; styleColor: "gray" }
    \endqml

    \sa style
 */
QColor QDeclarativeText::styleColor() const
{
    Q_D(const QDeclarativeText);
    return d->styleColor;
}

void QDeclarativeText::setStyleColor(const QColor &color)
{
    Q_D(QDeclarativeText);
    if (d->styleColor == color)
        return;

    d->styleColor = color;
    d->invalidateImageCache();
    emit styleColorChanged(d->styleColor);
}


/*!
    \qmlproperty enumeration Text::horizontalAlignment
    \qmlproperty enumeration Text::verticalAlignment

    Sets the horizontal and vertical alignment of the text within the Text items
    width and height.  By default, the text is top-left aligned.

    The valid values for \c horizontalAlignment are \c Text.AlignLeft, \c Text.AlignRight, \c Text.AlignHCenter and
    \c Text.AlignJustify.  The valid values for \c verticalAlignment are \c Text.AlignTop, \c Text.AlignBottom
    and \c Text.AlignVCenter.

    Note that for a single line of text, the size of the text is the area of the text. In this common case,
    all alignments are equivalent. If you want the text to be, say, centered in its parent, then you will
    need to either modify the Item::anchors, or set horizontalAlignment to Text.AlignHCenter and bind the width to 
    that of the parent.
*/
QDeclarativeText::HAlignment QDeclarativeText::hAlign() const
{
    Q_D(const QDeclarativeText);
    return d->hAlign;
}

void QDeclarativeText::setHAlign(HAlignment align)
{
    Q_D(QDeclarativeText);
    if (d->hAlign == align)
        return;

    if (isComponentComplete())
        prepareGeometryChange();

    d->hAlign = align;
    d->updateLayout();

    emit horizontalAlignmentChanged(align);
}

QDeclarativeText::VAlignment QDeclarativeText::vAlign() const
{
    Q_D(const QDeclarativeText);
    return d->vAlign;
}

void QDeclarativeText::setVAlign(VAlignment align)
{
    Q_D(QDeclarativeText);
    if (d->vAlign == align)
        return;

    if (isComponentComplete())
        prepareGeometryChange();
    d->vAlign = align;
    emit verticalAlignmentChanged(align);
}

/*!
    \qmlproperty enumeration Text::wrapMode

    Set this property to wrap the text to the Text item's width.  The text will only
    wrap if an explicit width has been set.  wrapMode can be one of:

    \list
    \o Text.NoWrap (default) - no wrapping will be performed. If the text contains insufficient newlines, then \l paintedWidth will exceed a set width.
    \o Text.WordWrap - wrapping is done on word boundaries only. If a word is too long, \l paintedWidth will exceed a set width.
    \o Text.WrapAnywhere - wrapping is done at any point on a line, even if it occurs in the middle of a word.
    \o Text.Wrap - if possible, wrapping occurs at a word boundary; otherwise it will occur at the appropriate point on the line, even in the middle of a word.
    \endlist
*/
QDeclarativeText::WrapMode QDeclarativeText::wrapMode() const
{
    Q_D(const QDeclarativeText);
    return d->wrapMode;
}

void QDeclarativeText::setWrapMode(WrapMode mode)
{
    Q_D(QDeclarativeText);
    if (mode == d->wrapMode)
        return;

    d->wrapMode = mode;
    d->updateLayout();
    
    emit wrapModeChanged();
}

/*!
    \qmlproperty int Text::lineCount

    Returns the number of lines visible in the text item.

    This property is not supported for rich text.

    \sa maximumLineCount
*/
int QDeclarativeText::lineCount() const
{
    Q_D(const QDeclarativeText);
    return d->lineCount;
}

/*!
    \qmlproperty bool Text::truncated

    Returns true if the text has been truncated due to \l maximumLineCount
    or \l elide.

    This property is not supported for rich text.

    \sa maximumLineCount, elide
*/
bool QDeclarativeText::truncated() const
{
    Q_D(const QDeclarativeText);
    return d->truncated;
}

/*!
    \qmlproperty int Text::maximumLineCount

    Set this property to limit the number of lines that the text item will show.
    If elide is set to Text.ElideRight, the text will be elided appropriately.
    By default, this is the value of the largest possible integer.

    This property is not supported for rich text.

    \sa lineCount, elide
*/
int QDeclarativeText::maximumLineCount() const
{
    Q_D(const QDeclarativeText);
    return d->maximumLineCount;
}

void QDeclarativeText::setMaximumLineCount(int lines)
{
    Q_D(QDeclarativeText);

    d->maximumLineCountValid = lines==INT_MAX ? false : true;
    if (d->maximumLineCount != lines) {
        d->maximumLineCount = lines;
        d->updateLayout();
        emit maximumLineCountChanged();
    }
}

void QDeclarativeText::resetMaximumLineCount()
{
    Q_D(QDeclarativeText);
    setMaximumLineCount(INT_MAX);
    d->elidePos = QPointF();
    if (d->truncated != false) {
        d->truncated = false;
        emit truncatedChanged();
    }
}

/*!
    \qmlproperty enumeration Text::textFormat

    The way the text property should be displayed.

    Supported text formats are:
    
    \list
    \o Text.AutoText (default)
    \o Text.PlainText
    \o Text.RichText
    \o Text.StyledText
    \endlist

    If the text format is \c Text.AutoText the text element
    will automatically determine whether the text should be treated as
    rich text.  This determination is made using Qt::mightBeRichText().

    Text.StyledText is an optimized format supporting some basic text
    styling markup, in the style of html 3.2:

    \code
    <font size="4" color="#ff0000">font size and color</font>
    <b>bold</b>
    <i>italic</i>
    <br>
    &gt; &lt; &amp;
    \endcode

    \c Text.StyledText parser is strict, requiring tags to be correctly nested.

    \table
    \row
    \o
    \qml
Column {
    Text {
        font.pointSize: 24
        text: "<b>Hello</b> <i>World!</i>"
    }
    Text {
        font.pointSize: 24
        textFormat: Text.RichText
        text: "<b>Hello</b> <i>World!</i>"
    }
    Text {
        font.pointSize: 24
        textFormat: Text.PlainText
        text: "<b>Hello</b> <i>World!</i>"
    }
}
    \endqml
    \o \image declarative-textformat.png
    \endtable
*/
QDeclarativeText::TextFormat QDeclarativeText::textFormat() const
{
    Q_D(const QDeclarativeText);
    return d->format;
}

void QDeclarativeText::setTextFormat(TextFormat format)
{
    Q_D(QDeclarativeText);
    if (format == d->format)
        return;
    d->format = format;
    bool wasRich = d->richText;
    d->richText = format == RichText || (format == AutoText && Qt::mightBeRichText(d->text));

    if (!wasRich && d->richText && isComponentComplete()) {
        d->ensureDoc();
        d->doc->setText(d->text);
    }

    d->updateLayout();

    emit textFormatChanged(d->format);
}

/*!
    \qmlproperty enumeration Text::elide

    Set this property to elide parts of the text fit to the Text item's width.
    The text will only elide if an explicit width has been set.

    This property cannot be used with rich text.

    Eliding can be:
    \list
    \o Text.ElideNone  - the default
    \o Text.ElideLeft
    \o Text.ElideMiddle
    \o Text.ElideRight
    \endlist

    If this property is set to Text.ElideRight, it can be used with multiline
    text. The text will only elide if maximumLineCount has been set.

    If the text is a multi-length string, and the mode is not \c Text.ElideNone,
    the first string that fits will be used, otherwise the last will be elided.

    Multi-length strings are ordered from longest to shortest, separated by the
    Unicode "String Terminator" character \c U009C (write this in QML with \c{"\u009C"} or \c{"\x9C"}).
*/
QDeclarativeText::TextElideMode QDeclarativeText::elideMode() const
{
    Q_D(const QDeclarativeText);
    return d->elideMode;
}

void QDeclarativeText::setElideMode(QDeclarativeText::TextElideMode mode)
{
    Q_D(QDeclarativeText);
    if (mode == d->elideMode)
        return;

    d->elideMode = mode;
    d->updateLayout();
    
    emit elideModeChanged(d->elideMode);
}

/*! \internal */
QRectF QDeclarativeText::boundingRect() const
{
    Q_D(const QDeclarativeText);

    int w = width();
    int h = height();

    int x = 0;
    int y = 0;

    QSize size = d->layedOutTextSize;
    if (d->style != Normal)
        size += QSize(2,2);

    // Could include font max left/right bearings to either side of rectangle.

    switch (d->hAlign) {
    case AlignLeft:
    case AlignJustify:
        x = 0;
        break;
    case AlignRight:
        x = w - size.width();
        break;
    case AlignHCenter:
        x = (w - size.width()) / 2;
        break;
    }

    switch (d->vAlign) {
    case AlignTop:
        y = 0;
        break;
    case AlignBottom:
        y = h - size.height();
        break;
    case AlignVCenter:
        y = (h - size.height()) / 2;
        break;
    }

    return QRectF(x,y,size.width(),size.height());
}

/*! \internal */
void QDeclarativeText::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)
{
    Q_D(QDeclarativeText);
    if ((!d->internalWidthUpdate && newGeometry.width() != oldGeometry.width())
            && (d->wrapMode != QDeclarativeText::NoWrap
                || d->elideMode != QDeclarativeText::ElideNone
                || d->hAlign != QDeclarativeText::AlignLeft)) {
        if ((d->singleline || d->maximumLineCountValid) && d->elideMode != QDeclarativeText::ElideNone && widthValid()) {
            // We need to re-elide
            d->updateLayout();
        } else {
            // We just need to re-layout
            d->updateSize();
        }
    }

    QDeclarativeItem::geometryChanged(newGeometry, oldGeometry);
}

/*!
    \qmlproperty real Text::paintedWidth

    Returns the width of the text, including width past the width
    which is covered due to insufficient wrapping if WrapMode is set.
*/
qreal QDeclarativeText::paintedWidth() const
{
    Q_D(const QDeclarativeText);
    return d->paintedSize.width();
}

/*!
    \qmlproperty real Text::paintedHeight

    Returns the height of the text, including height past the height
    which is covered due to there being more text than fits in the set height.
*/
qreal QDeclarativeText::paintedHeight() const
{
    Q_D(const QDeclarativeText);
    return d->paintedSize.height();
}

/*!
    \qmlproperty real Text::lineHeight

    Sets the line height for the text.
    The value can be in pixels or a multiplier depending on lineHeightMode.

*/
qreal QDeclarativeText::lineHeight() const
{
    Q_D(const QDeclarativeText);
    return d->lineHeight;
}

void QDeclarativeText::setLineHeight(qreal lineHeight)
{
    Q_D(QDeclarativeText);

    if ((d->lineHeight == lineHeight) || (lineHeight < 0.0))
        return;

    d->lineHeight = lineHeight;
    d->updateLayout();
    emit lineHeightChanged(lineHeight);
}

/*!
    \qmlproperty real Text::lineHeightMode

    This property determines how the line height is specified.
    The possible values are:

    \list
    \o Text.MultiplyHeight (default) - specifies a line height multiplier,
    \o Text.PixelHeight - specifies the line height in pixels.
    \endlist
*/
QDeclarativeText::LineHeightMode QDeclarativeText::lineHeightMode() const
{
    Q_D(const QDeclarativeText);
    return d->lineHeightMode;
}

void QDeclarativeText::setLineHeightMode(LineHeightMode mode)
{
    Q_D(QDeclarativeText);
    if (mode == d->lineHeightMode)
        return;

    d->lineHeightMode = mode;
    d->updateLayout();

    emit lineHeightModeChanged(mode);
}

/*!
    Returns the number of resources (images) that are being loaded asynchronously.
*/
int QDeclarativeText::resourcesLoading() const
{
    Q_D(const QDeclarativeText);
    return d->doc ? d->doc->resourcesLoading() : 0;
}

/*! \internal */
void QDeclarativeText::paint(QPainter *p, const QStyleOptionGraphicsItem *, QWidget *)
{
    Q_D(QDeclarativeText);

    if (d->cacheAllTextAsImage || d->style != Normal) {
        d->checkImageCache();
        if (d->imageCache.isNull())
            return;

        bool oldAA = p->testRenderHint(QPainter::Antialiasing);
        bool oldSmooth = p->testRenderHint(QPainter::SmoothPixmapTransform);
        if (d->smooth)
            p->setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform, d->smooth);

        QRect br = boundingRect().toRect();

        bool needClip = clip() && (d->imageCache.width() > width() ||
                                   d->imageCache.height() > height());

        if (needClip)
            p->drawPixmap(0, 0, width(), height(), d->imageCache, -br.x(), -br.y(), width(), height());
        else
            p->drawPixmap(br.x(), br.y(), d->imageCache);

        if (d->smooth) {
            p->setRenderHint(QPainter::Antialiasing, oldAA);
            p->setRenderHint(QPainter::SmoothPixmapTransform, oldSmooth);
        }
    } else {
        QRectF bounds = boundingRect();

        bool needClip = clip() && (d->layedOutTextSize.width() > width() ||
                                   d->layedOutTextSize.height() > height());

        if (needClip) {
            p->save();
            p->setClipRect(0, 0, width(), height(), Qt::IntersectClip);
        }
        if (d->richText) {
            QAbstractTextDocumentLayout::PaintContext context;
            context.palette.setColor(QPalette::Text, d->color);
            p->translate(bounds.x(), bounds.y());
            d->doc->documentLayout()->draw(p, context);
            p->translate(-bounds.x(), -bounds.y());
        } else {
            d->drawTextLayout(p, QPointF(0, bounds.y()), false);
        }

        if (needClip) {
            p->restore();
        }
    }
}

/*! \internal */
void QDeclarativeText::componentComplete()
{
    Q_D(QDeclarativeText);
    QDeclarativeItem::componentComplete();
    if (d->updateOnComponentComplete) {
        d->updateOnComponentComplete = false;
        if (d->richText) {
            d->ensureDoc();
            d->doc->setText(d->text);
        }
        d->updateLayout();
    }
}

/*!  \internal */
void QDeclarativeText::mousePressEvent(QGraphicsSceneMouseEvent *event)
{
    Q_D(QDeclarativeText);

    if (!d->richText || !d->doc || d->doc->documentLayout()->anchorAt(event->pos()).isEmpty()) {
        event->setAccepted(false);
        d->activeLink.clear();
    } else {
        d->activeLink = d->doc->documentLayout()->anchorAt(event->pos());
    }

    // ### may malfunction if two of the same links are clicked & dragged onto each other)

    if (!event->isAccepted())
        QDeclarativeItem::mousePressEvent(event);

}

/*! \internal */
void QDeclarativeText::mouseReleaseEvent(QGraphicsSceneMouseEvent *event)
{
    Q_D(QDeclarativeText);

        // ### confirm the link, and send a signal out
    if (d->richText && d->doc && d->activeLink == d->doc->documentLayout()->anchorAt(event->pos()))
        emit linkActivated(d->activeLink);
    else
        event->setAccepted(false);

    if (!event->isAccepted())
        QDeclarativeItem::mouseReleaseEvent(event);
}

QT_END_NAMESPACE

#include "qdeclarativetext.moc"