add single image PDF support

CCBUG: 299517

src/SkanliteImageSaver.cpp

@@ -11,10 +11,11 @@
 #include "SkanliteImageSaver.h"
 
 #include <QMutex>
-#include <QDebug>
-
-#include <KSaneWidget>
+#include <QString>
 #include <QUrl>
+#include <QImage>
+#include <QPdfWriter>
+#include <QPainter>
 
 struct SkanliteImageSaver::Private {
     bool   m_savedOk;
@@ -23,13 +24,13 @@ struct SkanliteImageSaver::Private {
     QUrl       m_url;
     QString    m_name;
     QImage     m_image;
-    int        m_dpi;
     QString    m_fileFormat;
     int        m_quality;
 
     SkanliteImageSaver *q;
 
     bool saveQImage();
+    bool savePDF();
 };
 
 // ------------------------------------------------------------------------
@@ -62,7 +63,12 @@ bool SkanliteImageSaver::saveQImage(const QUrl &url, const QString &name, const
 
 void SkanliteImageSaver::run()
 {
-    d->m_savedOk = d->saveQImage();
+    if (d->m_fileFormat == QLatin1String("pdf")) {
+        d->m_savedOk = d->savePDF();
+    } else {
+        d->m_savedOk = d->saveQImage();
+    }
+
     Q_EMIT imageSaved(d->m_url, d->m_name, d->m_savedOk);
 
     d->m_runMutex.unlock();
@@ -73,3 +79,26 @@ bool SkanliteImageSaver::Private::saveQImage()
     return m_image.save(m_name, qPrintable(m_fileFormat), m_quality);
 }
 
+bool SkanliteImageSaver::Private::savePDF()
+{
+    const QPageSize pageSize = QPageSize(QSizeF(m_image.width() * 1000.0 / m_image.dotsPerMeterX() , m_image.height() * 1000.0 / m_image.dotsPerMeterY()), QPageSize::Millimeter);
+    const int dpi = qRound(m_image.dotsPerMeterX() / 1000.0 * 25.4);
+
+    QPainter painter;
+    QPdfWriter writer(m_name);
+    writer.setPageOrientation(QPageLayout::Portrait);
+    writer.setResolution(dpi);
+    writer.setPageSize(pageSize);
+    writer.setPageMargins(QMarginsF(0, 0, 0, 0));
+    writer.setCreator(QStringLiteral("Skanlite"));
+    writer.setTitle(m_name);
+
+    QRect paintArea(0, 0, writer.width(), writer.height());
+    if (!painter.begin(&writer)) {
+        return false;
+    }
+
+    painter.drawImage(paintArea, m_image);
+
+    return painter.end();
+}

src/skanlite.cpp

@@ -144,6 +144,7 @@ Skanlite::Skanlite(const QString &device, QWidget *parent)
         m_filterList.insert(0, QStringLiteral("image/png"));
         m_filterList.insert(1, QStringLiteral("image/jpeg"));
         m_filterList.insert(2, QStringLiteral("image/tiff"));
+        m_filterList.insert(3, QStringLiteral("application/pdf"));
 
         m_filter16BitList << QStringLiteral("image/png");
         m_filter16BitList << QStringLiteral("image/tiff");
@@ -511,6 +512,9 @@ void Skanlite::saveImage()
     if (suffix.isEmpty()) {
         fileFormat = QStringLiteral("png");
     }
+    if (suffix == QLatin1String("pdf")) {
+        fileFormat = QStringLiteral("pdf");
+    }
 
     if (!fileUrl.isLocalFile()) {
         QTemporaryFile tmp;