Support inline images with <img> tag in StyledText

Task-number: QTBUG-21793
Change-Id: Ie7b9f293c6c9a949c1899152c38b61251b0069d3
Reviewed-by: Yann Bodson <yann.bodson@nokia.com>

5 files changed, 276 insertions, 29 deletions

diff --git a/src/quick/items/qquicktext.cpp b/src/quick/items/qquicktext.cpp
index 16fbc85b77..e7673478bd 100644
--- a/src/quick/items/qquicktext.cpp
+++ b/src/quick/items/qquicktext.cpp
@@ -58,12 +58,13 @@
 #include <QtGui/qguiapplication.h>
 #include <QtGui/qinputpanel.h>
 
-#include <private/qdeclarativestyledtext_p.h>
 #include <QtQuick/private/qdeclarativepixmapcache_p.h>
 
 #include <qmath.h>
 #include <limits.h>
 
+DEFINE_BOOL_CONFIG_OPTION(qmlTextDebug, QML_TEXT_DEBUG)
+
 QT_BEGIN_NAMESPACE
 
 extern Q_GUI_EXPORT bool qt_applefontsmoothing_enabled;
@@ -85,12 +86,12 @@ QQuickTextPrivate::QQuickTextPrivate()
   disableDistanceField(false), internalWidthUpdate(false),
   requireImplicitWidth(false), truncated(false), hAlignImplicit(true), rightToLeftText(false),
   layoutTextElided(false), richTextAsImage(false), textureImageCacheDirty(false), textHasChanged(true),
-  naturalWidth(0), doc(0), elipsisLayout(0), textLine(0), nodeType(NodeIsNull), updateType(UpdatePaintNode)
+  needToUpdateLayout(false), naturalWidth(0), doc(0), elipsisLayout(0), textLine(0), nodeType(NodeIsNull),
+  updateType(UpdatePaintNode), nbActiveDownloads(0)
 
 #if defined(Q_OS_MAC)
 , layoutThread(0), paintingThread(0)
 #endif
-
 {
     cacheAllTextAsImage = enableImageCache();
     disableDistanceField = qmlDisableDistanceField();
@@ -266,6 +267,8 @@ QQuickTextPrivate::~QQuickTextPrivate()
     delete elipsisLayout;
     delete textLine; textLine = 0;
     delete imageCache;
+    qDeleteAll(imgTags);
+    imgTags.clear();
 }
 
 qreal QQuickTextPrivate::getImplicitWidth() const
@@ -295,6 +298,11 @@ void QQuickTextPrivate::updateLayout()
     }
     updateOnComponentComplete = false;
     layoutTextElided = false;
+
+    if (!visibleImgTags.isEmpty())
+        visibleImgTags.clear();
+    needToUpdateLayout = false;
+
     // Setup instance of QTextLayout for all cases other than richtext
     if (!richText) {
         if (elipsisLayout) {
@@ -329,7 +337,7 @@ void QQuickTextPrivate::updateLayout()
         } else {
             singleline = false;
             if (textHasChanged) {
-                QDeclarativeStyledText::parse(text, layout);
+                QDeclarativeStyledText::parse(text, layout, imgTags, qmlContext(q), !maximumLineCountValid);
                 textHasChanged = false;
             }
         }
@@ -346,6 +354,41 @@ void QQuickTextPrivate::updateLayout()
     }
 
     updateSize();
+
+    if (needToUpdateLayout) {
+        needToUpdateLayout = false;
+        textHasChanged = true;
+        updateLayout();
+    }
+}
+
+void QQuickText::imageDownloadFinished()
+{
+    Q_D(QQuickText);
+
+    (d->nbActiveDownloads)--;
+
+    // when all the remote images have been downloaded,
+    // if one of the sizes was not specified at parsing time
+    // we use the implicit size from pixmapcache and re-layout.
+
+    if (d->nbActiveDownloads == 0) {
+        bool needToUpdateLayout = false;
+        foreach (QDeclarativeStyledTextImgTag *img, d->visibleImgTags) {
+            if (!img->size.isValid()) {
+                img->size = img->pix->implicitSize();
+                needToUpdateLayout = true;
+            }
+        }
+
+        if (needToUpdateLayout) {
+            d->textHasChanged = true;
+            d->updateLayout();
+        } else {
+            d->updateType = QQuickTextPrivate::UpdatePaintNode;
+            update();
+        }
+    }
 }
 
 void QQuickTextPrivate::updateSize()
@@ -659,6 +702,7 @@ QRect QQuickTextPrivate::setupTextLayout()
         lineWidth = INT_MAX;
     int linesLeft = maximumLineCount;
     int visibleTextLength = 0;
+
     forever {
         QTextLine line = layout.createLine();
         if (!line.isValid())
@@ -667,13 +711,10 @@ QRect QQuickTextPrivate::setupTextLayout()
         visibleCount++;
 
         qreal preLayoutHeight = height;
-        if (customLayout) {
+        if (customLayout)
             setupCustomLineGeometry(line, height);
-        } else if (lineWidth) {
-            line.setLineWidth(lineWidth);
-            line.setPosition(QPointF(line.position().x(), height));
-            height += (lineHeightMode == QQuickText::FixedHeight) ? lineHeight : line.height() * lineHeight;
-        }
+        else if (lineWidth)
+            setLineGeometry(line, lineWidth, height);
 
         bool elide = false;
         if (multilineElideEnabled && q->heightValid() && height > q->height()) {
@@ -682,7 +723,7 @@ QRect QQuickTextPrivate::setupTextLayout()
             if (visibleCount > 1) {
                 --visibleCount;
                 height = preLayoutHeight;
-                line.setLineWidth(0.0);
+                setLineGeometry(line, 0.0, height);
                 line.setPosition(QPointF(FLT_MAX,FLT_MAX));
                 line = layout.lineAt(visibleCount-1);
             }
@@ -693,13 +734,14 @@ QRect QQuickTextPrivate::setupTextLayout()
         if (elide || (maximumLineCountValid && --linesLeft == 0)) {
             if (visibleTextLength < text.length()) {
                 truncate = true;
+                height = preLayoutHeight;
                 if (multilineElideEnabled) {
                     qreal elideWidth = fm.width(elideChar);
                     // Need to correct for alignment
                     if (customLayout)
                         setupCustomLineGeometry(line, height, elideWidth);
                     else
-                        line.setLineWidth(lineWidth - elideWidth);
+                        setLineGeometry(line, lineWidth - elideWidth, height);
                     if (layout.text().mid(line.textStart(), line.textLength()).isRightToLeft()) {
                         line.setPosition(QPointF(line.position().x() + elideWidth, line.position().y()));
                         elidePos.setX(line.naturalTextRect().left() - elideWidth);
@@ -722,6 +764,7 @@ QRect QQuickTextPrivate::setupTextLayout()
         br = br.united(line.naturalTextRect());
     }
     layout.endLayout();
+    br.moveTop(0);
 
     //Update truncated
     if (truncated != truncate) {
@@ -740,10 +783,71 @@ QRect QQuickTextPrivate::setupTextLayout()
         lineCount = visibleCount;
         emit q->lineCountChanged();
     }
-
     return QRect(qRound(br.x()), qRound(br.y()), qCeil(br.width()), qCeil(br.height()));
 }
 
+void QQuickTextPrivate::setLineGeometry(QTextLine &line, qreal lineWidth, qreal &height)
+{
+    Q_Q(QQuickText);
+    line.setLineWidth(lineWidth);
+
+    if (imgTags.isEmpty()) {
+        line.setPosition(QPointF(line.position().x(), height));
+        height += (lineHeightMode == QQuickText::FixedHeight) ? lineHeight : line.height() * lineHeight;
+        return;
+    }
+
+    qreal textTop = 0;
+    qreal textHeight = line.height();
+    qreal totalLineHeight = textHeight;
+
+    QList<QDeclarativeStyledTextImgTag *> imagesInLine;
+
+    foreach (QDeclarativeStyledTextImgTag *image, imgTags) {
+        if (image->position >= line.textStart() &&
+            image->position < line.textStart() + line.textLength()) {
+
+            if (!image->pix) {
+                QUrl url = qmlContext(q)->resolvedUrl(image->url);
+                image->pix = new QDeclarativePixmap(qmlEngine(q), url, image->size);
+                if (image->pix->isLoading()) {
+                    image->pix->connectFinished(q, SLOT(imageDownloadFinished()));
+                    nbActiveDownloads++;
+                } else if (image->pix->isReady()) {
+                    if (!image->size.isValid()) {
+                        image->size = image->pix->implicitSize();
+                        // if the size of the image was not explicitly set, we need to
+                        // call updateLayout() once again.
+                        needToUpdateLayout = true;
+                    }
+                } else if (image->pix->isError()) {
+                    qmlInfo(q) << image->pix->error();
+                }
+            }
+
+            qreal ih = qreal(image->size.height());
+            if (image->align == QDeclarativeStyledTextImgTag::Top)
+                image->pos.setY(0);
+            else if (image->align == QDeclarativeStyledTextImgTag::Middle)
+                image->pos.setY((textHeight / 2.0) - (ih / 2.0));
+            else
+                image->pos.setY(textHeight - ih);
+            imagesInLine << image;
+            textTop = qMax(textTop, qAbs(image->pos.y()));
+        }
+    }
+
+    foreach (QDeclarativeStyledTextImgTag *image, imagesInLine) {
+        totalLineHeight = qMax(totalLineHeight, textTop + image->pos.y() + image->size.height());
+        image->pos.setX(line.cursorToX(image->position));
+        image->pos.setY(image->pos.y() + height + textTop);
+        visibleImgTags << image;
+    }
+
+    line.setPosition(QPointF(line.position().x(), height + textTop));
+    height += (lineHeightMode == QQuickText::FixedHeight) ? lineHeight : totalLineHeight * lineHeight;
+}
+
 /*!
     Returns a painted version of the QQuickTextPrivate::layout QTextLayout.
     If \a drawStyle is true, the style color overrides all colors in the document.
@@ -1251,6 +1355,8 @@ void QQuickText::setText(const QString &n)
         d->determineHorizontalAlignment();
     }
     d->textHasChanged = true;
+    qDeleteAll(d->imgTags);
+    d->imgTags.clear();
     d->updateLayout();
     emit textChanged(d->text);
 }
@@ -1629,6 +1735,7 @@ void QQuickText::resetMaximumLineCount()
     <font color="color_name" size="1-7"></font>
     <h1> to <h6> - headers
     <a href=""> - anchor
+    <img src="" align="top,middle,bottom" width="" height=""> - inline images
     <ol type="">, <ul type=""> and <li> - ordered and unordered lists
     <pre></pre> - preformatted
     &gt; &lt; &amp;
@@ -1947,6 +2054,24 @@ QSGNode *QQuickText::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeData *data
                 node->addTextLayout(QPoint(0, bounds.y()), d->elipsisLayout, d->color, d->style, d->styleColor);
         }
 
+        foreach (QDeclarativeStyledTextImgTag *img, d->visibleImgTags) {
+            if (qmlTextDebug()) {
+                QSGRectangleNode *rectangle = d->sceneGraphContext()->createRectangleNode();
+                rectangle->setRect(QRectF(img->pos.x(), img->pos.y() + bounds.y(),img->size.width(), img->size.height()));
+                rectangle->setColor(QColor("red"));
+                rectangle->update();
+                node->appendChildNode(rectangle);
+            }
+            QDeclarativePixmap *pix = img->pix;
+            if (pix && pix->isReady()) {
+                QSGTexture *texture = d->sceneGraphContext()->textureForFactory(pix->textureFactory());
+                QSGImageNode *imgnode = d->sceneGraphContext()->createImageNode();
+                imgnode->setTexture(texture);
+                imgnode->setTargetRect(QRectF(img->pos.x(), img->pos.y() + bounds.y(), pix->width(), pix->height()));
+                node->appendChildNode(imgnode);
+                imgnode->update();
+            }
+        }
         return node;
     }
 }
diff --git a/src/quick/items/qquicktext_p.h b/src/quick/items/qquicktext_p.h
index 0725f53c66..ddc9d38c75 100644
--- a/src/quick/items/qquicktext_p.h
+++ b/src/quick/items/qquicktext_p.h
@@ -44,9 +44,7 @@
 #define QQUICKTEXT_P_H
 
 #include "qquickimplicitsizeitem_p.h"
-
 #include <private/qtquickglobal_p.h>
-
 #include <QtGui/qtextoption.h>
 
 QT_BEGIN_HEADER
@@ -212,6 +210,7 @@ protected:
 private Q_SLOTS:
     void q_imagesLoaded();
     void triggerPreprocess();
+    void imageDownloadFinished();
 
 private:
     Q_DISABLE_COPY(QQuickText)
diff --git a/src/quick/items/qquicktext_p_p.h b/src/quick/items/qquicktext_p_p.h
index 40c50378f0..e7b0478e21 100644
--- a/src/quick/items/qquicktext_p_p.h
+++ b/src/quick/items/qquicktext_p_p.h
@@ -60,6 +60,7 @@
 #include <QtDeclarative/qdeclarative.h>
 #include <QtGui/qabstracttextdocumentlayout.h>
 #include <QtGui/qtextlayout.h>
+#include <private/qdeclarativestyledtext_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -82,6 +83,7 @@ public:
     void mirrorChange();
     QTextDocument *textDocument();
     bool isLineLaidOutConnected();
+    void setLineGeometry(QTextLine &line, qreal lineWidth, qreal &height);
 
     QString text;
     QUrl baseUrl;
@@ -127,6 +129,7 @@ public:
     bool richTextAsImage:1;
     bool textureImageCacheDirty:1;
     bool textHasChanged:1;
+    bool needToUpdateLayout:1;
 
     QRect layedOutTextRect;
     QSize paintedSize;
@@ -168,6 +171,10 @@ public:
     };
     UpdateType updateType;
 
+    QList<QDeclarativeStyledTextImgTag*> imgTags;
+    QList<QDeclarativeStyledTextImgTag*> visibleImgTags;
+    int nbActiveDownloads;
+
 #if defined(Q_OS_MAC)
     QList<QRectF> linesRects;
     QThread *layoutThread;
diff --git a/src/quick/util/qdeclarativestyledtext.cpp b/src/quick/util/qdeclarativestyledtext.cpp
index d34601d09f..39ea6b1a22 100644
--- a/src/quick/util/qdeclarativestyledtext.cpp
+++ b/src/quick/util/qdeclarativestyledtext.cpp
@@ -46,6 +46,7 @@
 #include <QDebug>
 #include <qmath.h>
 #include "qdeclarativestyledtext_p.h"
+#include <QDeclarativeContext>
 
 /*
     QDeclarativeStyledText supports few tags:
@@ -61,6 +62,7 @@
     <a href=""> - anchor
     <ol type="">, <ul type=""> and <li> - ordered and unordered lists
     <pre></pre> - preformated
+    <img src=""> - images
 
     The opening and closing tags must be correctly nested.
 */
@@ -79,9 +81,12 @@ public:
         ListFormat format;
     };
 
-    QDeclarativeStyledTextPrivate(const QString &t, QTextLayout &l)
-        : text(t), layout(l), baseFont(layout.font()), hasNewLine(false)
-        , preFormat(false), prependSpace(false), hasSpace(true)
+    QDeclarativeStyledTextPrivate(const QString &t, QTextLayout &l,
+                                  QList<QDeclarativeStyledTextImgTag*> &imgTags,
+                                  QDeclarativeContext *context,
+                                  bool preloadImages)
+        : text(t), layout(l), imgTags(&imgTags), baseFont(layout.font()), hasNewLine(false), nbImages(0), updateImagePositions(false)
+        , preFormat(false), prependSpace(false), hasSpace(true), preloadImages(preloadImages), context(context)
     {
     }
 
@@ -94,6 +99,7 @@ public:
     bool parseOrderedListAttributes(const QChar *&ch, const QString &textIn);
     bool parseUnorderedListAttributes(const QChar *&ch, const QString &textIn);
     bool parseAnchorAttributes(const QChar *&ch, const QString &textIn, QTextCharFormat &format);
+    void parseImageAttributes(const QChar *&ch, const QString &textIn, QString &textOut);
     QPair<QStringRef,QStringRef> parseAttribute(const QChar *&ch, const QString &textIn);
     QStringRef parseValue(const QChar *&ch, const QString &textIn);
 
@@ -108,12 +114,17 @@ public:
 
     QString text;
     QTextLayout &layout;
+    QList<QDeclarativeStyledTextImgTag*> *imgTags;
     QFont baseFont;
     QStack<List> listStack;
     bool hasNewLine;
+    int nbImages;
+    bool updateImagePositions;
     bool preFormat;
     bool prependSpace;
     bool hasSpace;
+    bool preloadImages;
+    QDeclarativeContext *context;
 
     static const QChar lessThan;
     static const QChar greaterThan;
@@ -143,8 +154,10 @@ const QChar QDeclarativeStyledTextPrivate::square(0x25a1);
 const QChar QDeclarativeStyledTextPrivate::lineFeed(QLatin1Char('\n'));
 const QChar QDeclarativeStyledTextPrivate::space(QLatin1Char(' '));
 
-QDeclarativeStyledText::QDeclarativeStyledText(const QString &string, QTextLayout &layout)
-: d(new QDeclarativeStyledTextPrivate(string, layout))
+QDeclarativeStyledText::QDeclarativeStyledText(const QString &string, QTextLayout &layout,
+                                               QList<QDeclarativeStyledTextImgTag*> &imgTags, QDeclarativeContext *context,
+                                               bool preloadImages)
+    : d(new QDeclarativeStyledTextPrivate(string, layout, imgTags, context, preloadImages))
 {
 }
 
@@ -153,11 +166,13 @@ QDeclarativeStyledText::~QDeclarativeStyledText()
     delete d;
 }
 
-void QDeclarativeStyledText::parse(const QString &string, QTextLayout &layout)
+void QDeclarativeStyledText::parse(const QString &string, QTextLayout &layout,
+                                   QList<QDeclarativeStyledTextImgTag*> &imgTags, QDeclarativeContext *context,
+                                   bool preloadImages)
 {
     if (string.isEmpty())
         return;
-    QDeclarativeStyledText styledText(string, layout);
+    QDeclarativeStyledText styledText(string, layout, imgTags, context, preloadImages);
     styledText.d->parse();
 }
 
@@ -169,6 +184,8 @@ void QDeclarativeStyledTextPrivate::parse()
     QString drawText;
     drawText.reserve(text.count());
 
+    updateImagePositions = !imgTags->isEmpty();
+
     int textStart = 0;
     int textLength = 0;
     int rangeStart = 0;
@@ -401,6 +418,10 @@ bool QDeclarativeStyledTextPrivate::parseTag(const QChar *&ch, const QString &te
             if (tag == QLatin1String("a")) {
                 return parseAnchorAttributes(ch, textIn, format);
             }
+            if (tag == QLatin1String("img")) {
+                parseImageAttributes(ch, textIn, textOut);
+                return false;
+            }
             if (*ch == greaterThan || ch->isNull())
                 continue;
         } else if (*ch != slash) {
@@ -606,6 +627,69 @@ bool QDeclarativeStyledTextPrivate::parseAnchorAttributes(const QChar *&ch, cons
     return valid;
 }
 
+void QDeclarativeStyledTextPrivate::parseImageAttributes(const QChar *&ch, const QString &textIn, QString &textOut)
+{
+    qreal imgWidth = 0.0;
+
+    if (!updateImagePositions) {
+        QDeclarativeStyledTextImgTag *image = new QDeclarativeStyledTextImgTag;
+        image->position = textOut.length() + 1;
+
+        QPair<QStringRef,QStringRef> attr;
+        do {
+            attr = parseAttribute(ch, textIn);
+            if (attr.first == QLatin1String("src")) {
+                image->url =  QUrl(attr.second.toString());
+            } else if (attr.first == QLatin1String("width")) {
+                image->size.setWidth(attr.second.toString().toInt());
+            } else if (attr.first == QLatin1String("height")) {
+                image->size.setHeight(attr.second.toString().toInt());
+            } else if (attr.first == QLatin1String("align")) {
+                if (attr.second.toString() == QLatin1String("top")) {
+                    image->align = QDeclarativeStyledTextImgTag::Top;
+                } else if (attr.second.toString() == QLatin1String("middle")) {
+                    image->align = QDeclarativeStyledTextImgTag::Middle;
+                }
+            }
+        } while (!ch->isNull() && !attr.first.isEmpty());
+
+        if (preloadImages && !image->size.isValid()) {
+            // if we don't know its size but the image is a local image,
+            // we load it in the pixmap cache and save its implicit size
+            // to avoid a relayout later on.
+            QUrl url = context->resolvedUrl(image->url);
+            if (url.isLocalFile()) {
+                QDeclarativePixmap *pix = new QDeclarativePixmap(context->engine(), url, image->size);
+                if (pix && pix->isReady()) {
+                    image->size = pix->implicitSize();
+                    image->pix = pix;
+                }
+            }
+        }
+
+        imgWidth = image->size.width();
+        imgTags->append(image);
+
+    } else {
+        // if we already have a list of img tags for this text
+        // we only want to update the positions of these tags.
+        QDeclarativeStyledTextImgTag *image = imgTags->value(nbImages);
+        image->position = textOut.length() + 1;
+        imgWidth = image->size.width();
+        QPair<QStringRef,QStringRef> attr;
+        do {
+            attr = parseAttribute(ch, textIn);
+        } while (!ch->isNull() && !attr.first.isEmpty());
+        nbImages++;
+    }
+
+    QFontMetricsF fm(layout.font());
+    QString padding(qFloor(imgWidth / fm.width(QChar::Nbsp)), QChar::Nbsp);
+    textOut += QChar(' ');
+    textOut += padding;
+    textOut += QChar(' ');
+}
+
 QPair<QStringRef,QStringRef> QDeclarativeStyledTextPrivate::parseAttribute(const QChar *&ch, const QString &textIn)
 {
     skipSpace(ch);
diff --git a/src/quick/util/qdeclarativestyledtext_p.h b/src/quick/util/qdeclarativestyledtext_p.h
index f3e9fef457..1c9086e7d1 100644
--- a/src/quick/util/qdeclarativestyledtext_p.h
+++ b/src/quick/util/qdeclarativestyledtext_p.h
@@ -42,23 +42,55 @@
 #ifndef QDECLARATIVESTYLEDTEXT_H
 #define QDECLARATIVESTYLEDTEXT_H
 
-#include <QSizeF>
+#include <QSize>
+#include <QPointF>
+#include <QList>
+#include <QUrl>
+#include <QtQuick/private/qdeclarativepixmapcache_p.h>
 
 QT_BEGIN_NAMESPACE
 
-class QPainter;
-class QPointF;
-class QString;
+class QDeclarativeStyledTextImgTag;
 class QDeclarativeStyledTextPrivate;
-class QTextLayout;
+class QString;
+class QDeclarativeContext;
+
+class Q_AUTOTEST_EXPORT QDeclarativeStyledTextImgTag
+{
+public:
+    QDeclarativeStyledTextImgTag()
+        : position(0), align(QDeclarativeStyledTextImgTag::Bottom), pix(0)
+    { }
+
+    ~QDeclarativeStyledTextImgTag() { delete pix; }
+
+    enum Align {
+        Bottom,
+        Middle,
+        Top
+    };
+
+    QUrl url;
+    QPointF pos;
+    QSize size;
+    int position;
+    Align align;
+    QDeclarativePixmap *pix;
+};
 
 class Q_AUTOTEST_EXPORT QDeclarativeStyledText
 {
 public:
-    static void parse(const QString &string, QTextLayout &layout);
+    static void parse(const QString &string, QTextLayout &layout,
+                      QList<QDeclarativeStyledTextImgTag*> &imgTags,
+                      QDeclarativeContext *context,
+                      bool preloadImages);
 
 private:
-    QDeclarativeStyledText(const QString &string, QTextLayout &layout);
+    QDeclarativeStyledText(const QString &string, QTextLayout &layout,
+                           QList<QDeclarativeStyledTextImgTag*> &imgTags,
+                           QDeclarativeContext *context,
+                           bool preloadImages);
     ~QDeclarativeStyledText();
 
     QDeclarativeStyledTextPrivate *d;