Fancier left/right signature visual representation

8 files changed, 172 insertions, 20 deletions

diff --git a/poppler/Annot.cc b/poppler/Annot.cc
index 7b7d37b3..0e36b209 100644
--- a/poppler/Annot.cc
+++ b/poppler/Annot.cc
@@ -4904,11 +4904,30 @@ bool AnnotAppearanceBuilder::drawFormFieldText(const FormFieldText *fieldText, c
 bool AnnotAppearanceBuilder::drawSignatureFieldText(const FormFieldSignature *field, const Form *form, const GfxResources *resources, const GooString *_da, const AnnotBorder *border, const AnnotAppearanceCharacs *appearCharacs,
                                                     const PDFRectangle *rect, XRef *xref, Dict *resourcesDict)
 {
-    DefaultAppearance da(_da);
     const GooString &contents = field->getCustomAppearanceContent();
     if (contents.toStr().empty())
         return false;
 
+    const GooString &leftText = field->getCustomAppearanceLeftContent();
+    if (leftText.toStr().empty()) {
+        drawSignatureFieldText(contents, DefaultAppearance(_da), border, rect, xref, resourcesDict, 0, false /* don't center vertically */, false /* don't center horizontally */);
+    } else {
+        DefaultAppearance daLeft(_da);
+        daLeft.setFontPtSize(field->getCustomAppearanceLeftFontSize());
+        const double halfWidth = (rect->x2 - rect->x1) / 2;
+        PDFRectangle rectLeft(rect->x1, rect->y1, rect->x1 + halfWidth, rect->y2);
+        drawSignatureFieldText(leftText, daLeft, border, &rectLeft, xref, resourcesDict, 0, true /* center vertically */, true /* center horizontally */);
+
+        PDFRectangle rectRight(rectLeft.x2, rect->y1, rect->x2, rect->y2);
+        drawSignatureFieldText(contents, DefaultAppearance(_da), border, &rectRight, xref, resourcesDict, halfWidth, true /* center vertically */, false /* don't center horizontally */);
+    }
+
+    return true;
+}
+
+void AnnotAppearanceBuilder::drawSignatureFieldText(const GooString &text, const DefaultAppearance &da, const AnnotBorder *border, const PDFRectangle *rect, XRef *xref, Dict *resourcesDict, double leftMargin, bool centerVertically,
+                                                    bool centerHorizontally)
+{
     double borderWidth = 0;
     append("q\n");
 
@@ -4921,40 +4940,58 @@ bool AnnotAppearanceBuilder::drawSignatureFieldText(const FormFieldSignature *fi
     // Box size
     const double width = rect->x2 - rect->x1;
     const double height = rect->y2 - rect->y1;
-
-    // Setup text clipping
     const double textmargin = borderWidth * 2;
     const double textwidth = width - 2 * textmargin;
-    appendf("{0:.2f} {0:.2f} {1:.2f} {2:.2f} re W n\n", textmargin, textwidth, height - 2 * textmargin);
-
-    GfxFont *font = nullptr;
 
     // create a Helvetica fake font
-    font = createAnnotDrawFont(xref, resourcesDict, da.getFontName().getName());
+    GfxFont *font = createAnnotDrawFont(xref, resourcesDict, da.getFontName().getName());
+
+    // calculate the string tokenization
+    int i = 0;
+    std::vector<std::pair<std::string, double>> outTexts;
+    while (i < text.getLength()) {
+        GooString out;
+        double textWidth;
+        Annot::layoutText(&text, &out, &i, font, &textWidth, textwidth / da.getFontPtSize(), nullptr, false);
+        outTexts.emplace_back(out.toStr(), textWidth * da.getFontPtSize());
+    }
+
+    // Setup text clipping
+    appendf("{0:.2f} {1:.2f} {2:.2f} {3:.2f} re W n\n", leftMargin + textmargin, textmargin, textwidth, height - 2 * textmargin);
 
     // Set font state
     setDrawColor(da.getFontColor(), true);
     appendf("BT 1 0 0 1 {0:.2f} {1:.2f} Tm\n", textmargin, height - textmargin - da.getFontPtSize() * font->getDescent());
     setTextFont(da.getFontName(), da.getFontPtSize());
 
-    int i = 0;
-    double xposPrev = 0;
-    while (i < contents.getLength()) {
-        GooString out;
-        double linewidth, xpos;
-        Annot::layoutText(&contents, &out, &i, font, &linewidth, textwidth / da.getFontPtSize(), nullptr, false);
-        linewidth *= da.getFontPtSize();
-        xpos = 0;
-        appendf("{0:.2f} {1:.2f} Td\n", xpos - xposPrev, -da.getFontPtSize());
-        writeString(out);
+    double xDelta = centerHorizontally ? 0 : leftMargin;
+    double currentX = 0;
+    double yDelta = -da.getFontPtSize();
+    if (centerVertically) {
+        const double outTextHeight = outTexts.size() * da.getFontPtSize();
+        if (outTextHeight < height) {
+            yDelta -= (height - outTextHeight) / 2;
+        }
+    }
+    for (const std::pair<std::string, double> &outText : outTexts) {
+        if (centerHorizontally) {
+            const double lineX = (width - outText.second) / 2;
+            xDelta = (lineX - currentX);
+            currentX += xDelta;
+        }
+
+        appendf("{0:.2f} {1:.2f} Td\n", xDelta, yDelta);
+        writeString(GooString(outText.first));
         append("Tj\n");
-        xposPrev = xpos;
+
+        if (!centerHorizontally) {
+            xDelta = 0;
+        }
+        yDelta = -da.getFontPtSize();
     }
 
     font->decRefCnt();
     append("ET Q\n");
-
-    return true;
 }
 
 bool AnnotAppearanceBuilder::drawFormFieldChoice(const FormFieldChoice *fieldChoice, const Form *form, const GfxResources *resources, const GooString *da, const AnnotBorder *border, const AnnotAppearanceCharacs *appearCharacs,
diff --git a/poppler/Annot.h b/poppler/Annot.h
index 5eb16472..0e97a50c 100644
--- a/poppler/Annot.h
+++ b/poppler/Annot.h
@@ -592,6 +592,7 @@ private:
     bool drawFormFieldChoice(const FormFieldChoice *fieldChoice, const Form *form, const GfxResources *resources, const GooString *da, const AnnotBorder *border, const AnnotAppearanceCharacs *appearCharacs, const PDFRectangle *rect);
     bool drawSignatureFieldText(const FormFieldSignature *field, const Form *form, const GfxResources *resources, const GooString *da, const AnnotBorder *border, const AnnotAppearanceCharacs *appearCharacs, const PDFRectangle *rect,
                                 XRef *xref, Dict *resourcesDict);
+    void drawSignatureFieldText(const GooString &text, const DefaultAppearance &da, const AnnotBorder *border, const PDFRectangle *rect, XRef *xref, Dict *resourcesDict, double leftMargin, bool centerVertically, bool centerHorizontally);
     bool drawText(const GooString *text, const GooString *da, const GfxResources *resources, const AnnotBorder *border, const AnnotAppearanceCharacs *appearCharacs, const PDFRectangle *rect, bool multiline, int comb, int quadding,
                   bool txField, bool forceZapfDingbats, XRef *xref, bool *addedDingbatsResource, // xref and addedDingbatsResource both must not be null if forceZapfDingbats is passed
                   bool password);
diff --git a/poppler/Form.cc b/poppler/Form.cc
index ff0e8d4a..b6488b59 100644
--- a/poppler/Form.cc
+++ b/poppler/Form.cc
@@ -2018,6 +2018,26 @@ void FormFieldSignature::setCustomAppearanceContent(const GooString &s)
     customAppearanceContent = GooString(s.toStr());
 }
 
+const GooString &FormFieldSignature::getCustomAppearanceLeftContent() const
+{
+    return customAppearanceLeftContent;
+}
+
+void FormFieldSignature::setCustomAppearanceLeftContent(const GooString &s)
+{
+    customAppearanceLeftContent = GooString(s.toStr());
+}
+
+double FormFieldSignature::getCustomAppearanceLeftFontSize() const
+{
+    return customAppearanceLeftFontSize;
+}
+
+void FormFieldSignature::setCustomAppearanceLeftFontSize(double size)
+{
+    customAppearanceLeftFontSize = size;
+}
+
 void FormFieldSignature::setCertificateInfo(std::unique_ptr<X509CertificateInfo> &certInfo)
 {
     certificate_info.swap(certInfo);
diff --git a/poppler/Form.h b/poppler/Form.h
index 4a796962..13ca1f5f 100644
--- a/poppler/Form.h
+++ b/poppler/Form.h
@@ -615,6 +615,12 @@ public:
     const GooString &getCustomAppearanceContent() const;
     void setCustomAppearanceContent(const GooString &s);
 
+    const GooString &getCustomAppearanceLeftContent() const;
+    void setCustomAppearanceLeftContent(const GooString &s);
+
+    double getCustomAppearanceLeftFontSize() const;
+    void setCustomAppearanceLeftFontSize(double size);
+
     void setCertificateInfo(std::unique_ptr<X509CertificateInfo> &);
 
     FormWidget *getCreateWidget();
@@ -628,6 +634,8 @@ private:
     GooString *signature;
     SignatureInfo *signature_info;
     GooString customAppearanceContent;
+    GooString customAppearanceLeftContent;
+    double customAppearanceLeftFontSize = 20;
     std::unique_ptr<X509CertificateInfo> certificate_info;
 
     void print(int indent) override;
diff --git a/qt5/src/poppler-pdf-converter.cc b/qt5/src/poppler-pdf-converter.cc
index d1355764..3f6b6447 100644
--- a/qt5/src/poppler-pdf-converter.cc
+++ b/qt5/src/poppler-pdf-converter.cc
@@ -156,6 +156,9 @@ bool PDFConverter::sign(const NewSignatureData &data)
     std::unique_ptr<GooString> gSignatureText = std::unique_ptr<GooString>(QStringToUnicodeGooString(data.signatureText()));
     field->setCustomAppearanceContent(*gSignatureText);
 
+    std::unique_ptr<GooString> gSignatureLeftText = std::unique_ptr<GooString>(QStringToUnicodeGooString(data.signatureLeftText()));
+    field->setCustomAppearanceLeftContent(*gSignatureLeftText);
+
     Object refObj(ref);
     AnnotWidget *signatureAnnot = new AnnotWidget(doc, &annotObj, &refObj, field.get());
     signatureAnnot->setFlags(signatureAnnot->getFlags() | Annot::flagPrint | Annot::flagLocked | Annot::flagNoRotate);
@@ -208,7 +211,9 @@ struct PDFConverter::NewSignatureData::NewSignatureDataPrivate
     int page;
     QRectF boundingRectangle;
     QString signatureText;
+    QString signatureLeftText;
     double fontSize = 10.0;
+    double leftFontSize = 20.0;
     QColor fontColor = Qt::red;
     QColor borderColor = Qt::red;
     double borderWidth = 1.5;
@@ -274,6 +279,16 @@ void PDFConverter::NewSignatureData::setSignatureText(const QString &text)
     d->signatureText = text;
 }
 
+QString PDFConverter::NewSignatureData::signatureLeftText() const
+{
+    return d->signatureLeftText;
+}
+
+void PDFConverter::NewSignatureData::setSignatureLeftText(const QString &text)
+{
+    d->signatureLeftText = text;
+}
+
 double PDFConverter::NewSignatureData::fontSize() const
 {
     return d->fontSize;
@@ -284,6 +299,16 @@ void PDFConverter::NewSignatureData::setFontSize(double fontSize)
     d->fontSize = fontSize;
 }
 
+double PDFConverter::NewSignatureData::leftFontSize() const
+{
+    return d->leftFontSize;
+}
+
+void PDFConverter::NewSignatureData::setLeftFontSize(double fontSize)
+{
+    d->leftFontSize = fontSize;
+}
+
 QColor PDFConverter::NewSignatureData::fontColor() const
 {
     return d->fontColor;
diff --git a/qt5/src/poppler-qt5.h b/qt5/src/poppler-qt5.h
index a3163572..56bab8a2 100644
--- a/qt5/src/poppler-qt5.h
+++ b/qt5/src/poppler-qt5.h
@@ -2172,12 +2172,30 @@ public:
         void setSignatureText(const QString &text);
 
         /**
+         * If this text is not empty, the signature representation
+         * will split in two, with this text on the left and signatureText
+         * on the right
+         *
+         * \since 21.06
+         */
+        QString signatureLeftText() const;
+        void setSignatureLeftText(const QString &text);
+
+        /**
          * Default: 10
          */
         double fontSize() const;
         void setFontSize(double fontSize);
 
         /**
+         * Default: 20
+         *
+         * \since 21.06
+         */
+        double leftFontSize() const;
+        void setLeftFontSize(double fontSize);
+
+        /**
          * Default: red
          */
         QColor fontColor() const;
diff --git a/qt6/src/poppler-pdf-converter.cc b/qt6/src/poppler-pdf-converter.cc
index 62e6d535..a0a64d62 100644
--- a/qt6/src/poppler-pdf-converter.cc
+++ b/qt6/src/poppler-pdf-converter.cc
@@ -156,6 +156,9 @@ bool PDFConverter::sign(const NewSignatureData &data)
     std::unique_ptr<GooString> gSignatureText = std::unique_ptr<GooString>(QStringToUnicodeGooString(data.signatureText()));
     field->setCustomAppearanceContent(*gSignatureText);
 
+    std::unique_ptr<GooString> gSignatureLeftText = std::unique_ptr<GooString>(QStringToUnicodeGooString(data.signatureLeftText()));
+    field->setCustomAppearanceLeftContent(*gSignatureLeftText);
+
     Object refObj(ref);
     AnnotWidget *signatureAnnot = new AnnotWidget(doc, &annotObj, &refObj, field.get());
     signatureAnnot->setFlags(signatureAnnot->getFlags() | Annot::flagPrint | Annot::flagLocked | Annot::flagNoRotate);
@@ -208,7 +211,9 @@ struct PDFConverter::NewSignatureData::NewSignatureDataPrivate
     int page;
     QRectF boundingRectangle;
     QString signatureText;
+    QString signatureLeftText;
     double fontSize = 10.0;
+    double leftFontSize = 20.0;
     QColor fontColor = Qt::red;
     QColor borderColor = Qt::red;
     double borderWidth = 1.5;
@@ -274,6 +279,16 @@ void PDFConverter::NewSignatureData::setSignatureText(const QString &text)
     d->signatureText = text;
 }
 
+QString PDFConverter::NewSignatureData::signatureLeftText() const
+{
+    return d->signatureLeftText;
+}
+
+void PDFConverter::NewSignatureData::setSignatureLeftText(const QString &text)
+{
+    d->signatureLeftText = text;
+}
+
 double PDFConverter::NewSignatureData::fontSize() const
 {
     return d->fontSize;
@@ -284,6 +299,16 @@ void PDFConverter::NewSignatureData::setFontSize(double fontSize)
     d->fontSize = fontSize;
 }
 
+double PDFConverter::NewSignatureData::leftFontSize() const
+{
+    return d->leftFontSize;
+}
+
+void PDFConverter::NewSignatureData::setLeftFontSize(double fontSize)
+{
+    d->leftFontSize = fontSize;
+}
+
 QColor PDFConverter::NewSignatureData::fontColor() const
 {
     return d->fontColor;
diff --git a/qt6/src/poppler-qt6.h b/qt6/src/poppler-qt6.h
index b59d9add..dbef56ae 100644
--- a/qt6/src/poppler-qt6.h
+++ b/qt6/src/poppler-qt6.h
@@ -1990,12 +1990,30 @@ public:
         void setSignatureText(const QString &text);
 
         /**
+         * If this text is not empty, the signature representation
+         * will split in two, with this text on the left and signatureText
+         * on the right
+         *
+         * \since 21.06
+         */
+        QString signatureLeftText() const;
+        void setSignatureLeftText(const QString &text);
+
+        /**
          * Default: 10
          */
         double fontSize() const;
         void setFontSize(double fontSize);
 
         /**
+         * Default: 20
+         *
+         * \since 21.06
+         */
+        double leftFontSize() const;
+        void setLeftFontSize(double fontSize);
+
+        /**
          * Default: red
          */
         QColor fontColor() const;