Undo/redo manager, fixing form bugs

PdfForQtLib/sources/pdfdocument.h

@@ -479,6 +479,8 @@ private:
     PDFCatalog m_catalog;
 };
 
+using PDFDocumentPointer = QSharedPointer<PDFDocument>;
+
 /// Helper class for document updates (for example, add/delete annotations,
 /// fill form fields, do some other minor operations) and also for major
 /// updates (document reset). It also contains modification flags, which are

PdfForQtLib/sources/pdfform.cpp

@@ -22,19 +22,19 @@
 namespace pdf
 {
 
-PDFForm PDFForm::parse(const PDFObjectStorage* storage, PDFObject object)
+PDFForm PDFForm::parse(const PDFDocument* document, PDFObject object)
 {
     PDFForm form;
 
-    if (const PDFDictionary* formDictionary = storage->getDictionaryFromObject(object))
+    if (const PDFDictionary* formDictionary = document->getDictionaryFromObject(object))
     {
-        PDFDocumentDataLoaderDecorator loader(storage);
+        PDFDocumentDataLoaderDecorator loader(document);
 
         std::vector<PDFObjectReference> fieldRoots = loader.readReferenceArrayFromDictionary(formDictionary, "Fields");
         form.m_formFields.reserve(fieldRoots.size());
         for (const PDFObjectReference& fieldRootReference : fieldRoots)
         {
-            form.m_formFields.emplace_back(PDFFormField::parse(storage, fieldRootReference, nullptr));
+            form.m_formFields.emplace_back(PDFFormField::parse(&document->getStorage(), fieldRootReference, nullptr));
         }
 
         form.m_formType = FormType::AcroForm;
@@ -51,11 +51,73 @@ PDFForm PDFForm::parse(const PDFObjectStorage* storage, PDFObject object)
             // Jakub Melka: handle XFA form
             form.m_formType = FormType::XFAForm;
         }
+
+        // As post-processing, delete all form fields, which are nullptr (are incorrectly defined)
+        form.m_formFields.erase(std::remove_if(form.m_formFields.begin(), form.m_formFields.end(), [](const auto& field){ return !field; }), form.m_formFields.end());
+        form.updateWidgetToFormFieldMapping();
+
+        // If we have form, then we must also look for 'rogue' form fields, which are
+        // incorrectly not in the 'Fields' entry of this form. We do this by iterating
+        // all pages, and their annotations and try to find these 'rogue' fields.
+        bool rogueFieldFound = false;
+        const size_t pageCount = document->getCatalog()->getPageCount();
+        for (size_t i = 0; i < pageCount; ++i)
+        {
+            const PDFPage* page = document->getCatalog()->getPage(i);
+            for (PDFObjectReference annotationReference : page->getAnnotations())
+            {
+                const PDFDictionary* annotationDictionary = document->getDictionaryFromObject(document->getObjectByReference(annotationReference));
+
+                if (form.m_widgetToFormField.count(annotationReference))
+                {
+                    // This widget/form field is already present
+                    continue;
+                }
+
+                if (loader.readNameFromDictionary(annotationDictionary, "Subtype") == "Widget")
+                {
+                    rogueFieldFound = true;
+                    form.m_formFields.emplace_back(PDFFormField::parse(&document->getStorage(), annotationReference, nullptr));
+                }
+            }
+        }
+
+        // As post-processing, delete all form fields, which are nullptr (are incorrectly defined)
+        form.m_formFields.erase(std::remove_if(form.m_formFields.begin(), form.m_formFields.end(), [](const auto& field){ return !field; }), form.m_formFields.end());
+
+        if (rogueFieldFound)
+        {
+            form.updateWidgetToFormFieldMapping();
+        }
     }
 
     return form;
 }
 
+void PDFForm::updateWidgetToFormFieldMapping()
+{
+    m_widgetToFormField.clear();
+
+    if (isAcroForm() || isXFAForm())
+    {
+        for (const PDFFormFieldPointer& formFieldPtr : getFormFields())
+        {
+            formFieldPtr->fillWidgetToFormFieldMapping(m_widgetToFormField);
+        }
+    }
+}
+
+const PDFFormField* PDFForm::getFormFieldForWidget(PDFObjectReference widget) const
+{
+    auto it = m_widgetToFormField.find(widget);
+    if (it != m_widgetToFormField.cend())
+    {
+        return it->second;
+    }
+
+    return nullptr;
+}
+
 void PDFFormField::fillWidgetToFormFieldMapping(PDFWidgetToFormFieldMapping& mapping)
 {
     for (const auto& childField : m_childFields)
@@ -142,6 +204,34 @@ PDFFormFieldPointer PDFFormField::parse(const PDFObjectStorage* storage, PDFObje
         }
         result.reset(formField);
 
+        PDFObject parentV = parentField ? parentField->getValue() : PDFObject();
+        PDFObject parentDV = parentField ? parentField->getDefaultValue() : PDFObject();
+        FieldFlags parentFlags = parentField ? parentField->getFlags() : None;
+
+        formField->m_selfReference = reference;
+        formField->m_fieldType = formFieldType;
+        formField->m_parentField = parentField;
+        formField->m_fieldNames[Partial] = loader.readTextStringFromDictionary(fieldDictionary, "T", QString());
+        formField->m_fieldNames[UserCaption] = loader.readTextStringFromDictionary(fieldDictionary, "TU", QString());
+        formField->m_fieldNames[Export] = loader.readTextStringFromDictionary(fieldDictionary, "TM", QString());
+        formField->m_fieldFlags = fieldDictionary->hasKey("Ff") ? static_cast<FieldFlags>(loader.readIntegerFromDictionary(fieldDictionary, "Ff", 0)) : parentFlags;
+        formField->m_value = fieldDictionary->hasKey("V") ? fieldDictionary->get("V") : parentV;
+        formField->m_defaultValue = fieldDictionary->hasKey("DV") ? fieldDictionary->get("DV") : parentDV;
+        formField->m_additionalActions = PDFAnnotationAdditionalActions::parse(storage, fieldDictionary->get("AA"));
+
+        // Generate fully qualified name. If partial name is empty, then fully qualified name
+        // is generated from parent fully qualified name (i.e. it is same as parent's name).
+        // This is according the PDF specification 1.7.
+        QStringList names;
+        if (parentField)
+        {
+            names << parentField->getName(FullyQualified);
+        }
+        names << formField->m_fieldNames[Partial];
+        names.removeAll(QString());
+
+        formField->m_fieldNames[FullyQualified] = names.join(".");
+
         std::vector<PDFObjectReference> kids = loader.readReferenceArrayFromDictionary(fieldDictionary, "Kids");
         if (kids.empty())
         {
@@ -182,22 +272,6 @@ PDFFormFieldPointer PDFFormField::parse(const PDFObjectStorage* storage, PDFObje
 
         }
 
-        PDFObject parentV = parentField ? parentField->getValue() : PDFObject();
-        PDFObject parentDV = parentField ? parentField->getDefaultValue() : PDFObject();
-        FieldFlags parentFlags = parentField ? parentField->getFlags() : None;
-
-        formField->m_selfReference = reference;
-        formField->m_fieldType = formFieldType;
-        formField->m_parentField = parentField;
-        formField->m_fieldNames[Partial] = loader.readTextStringFromDictionary(fieldDictionary, "T", QString());
-        formField->m_fieldNames[UserCaption] = loader.readTextStringFromDictionary(fieldDictionary, "TU", QString());
-        formField->m_fieldNames[Export] = loader.readTextStringFromDictionary(fieldDictionary, "TM", QString());
-        formField->m_fieldNames[FullyQualified] = parentField ? QString("%1.%2").arg(parentField->getName(FullyQualified), formField->m_fieldNames[Partial]) : formField->m_fieldNames[Partial];
-        formField->m_fieldFlags = fieldDictionary->hasKey("Ff") ? static_cast<FieldFlags>(loader.readIntegerFromDictionary(fieldDictionary, "Ff", 0)) : parentFlags;
-        formField->m_value = fieldDictionary->hasKey("V") ? fieldDictionary->get("V") : parentV;
-        formField->m_defaultValue = fieldDictionary->hasKey("DV") ? fieldDictionary->get("DV") : parentDV;
-        formField->m_additionalActions = PDFAnnotationAdditionalActions::parse(storage, fieldDictionary->get("AA"));
-
         if (formFieldButton)
         {
             formFieldButton->m_options = loader.readTextStringList(fieldDictionary->get("Opt"));
@@ -297,17 +371,6 @@ PDFFormManager::~PDFFormManager()
 
 }
 
-const PDFFormField* PDFFormManager::getFormFieldForWidget(PDFObjectReference widget) const
-{
-    auto it = m_widgetToFormField.find(widget);
-    if (it != m_widgetToFormField.cend())
-    {
-        return it->second;
-    }
-
-    return nullptr;
-}
-
 PDFAnnotationManager* PDFFormManager::getAnnotationManager() const
 {
     return m_annotationManager;
@@ -333,15 +396,13 @@ void PDFFormManager::setDocument(const PDFModifiedDocument& document)
         {
             if (m_document)
             {
-                m_form = PDFForm::parse(&m_document->getStorage(), m_document->getCatalog()->getFormObject());
+                m_form = PDFForm::parse(m_document, m_document->getCatalog()->getFormObject());
             }
             else
             {
                 // Clean the form
                 m_form = PDFForm();
             }
-
-            updateWidgetToFormFieldMapping();
         }
         else if (document.hasFlag(PDFModifiedDocument::FormField))
         {
@@ -372,17 +433,4 @@ void PDFFormManager::updateFieldValues()
     }
 }
 
-void PDFFormManager::updateWidgetToFormFieldMapping()
-{
-    m_widgetToFormField.clear();
-
-    if (hasAcroForm() || hasXFAForm())
-    {
-        for (const PDFFormFieldPointer& formFieldPtr : m_form.getFormFields())
-        {
-            formFieldPtr->fillWidgetToFormFieldMapping(m_widgetToFormField);
-        }
-    }
-}
-
 }   // namespace pdf

PdfForQtLib/sources/pdfform.h

@@ -329,13 +329,23 @@ public:
     const std::optional<PDFInteger>& getQuadding() const { return m_quadding; }
     const PDFObject& getXFA() const { return m_xfa; }
 
+    bool isAcroForm() const { return getFormType() == PDFForm::FormType::AcroForm; }
+    bool isXFAForm() const { return getFormType() == PDFForm::FormType::XFAForm; }
+
+    /// Returns form field for widget. If widget doesn't have attached form field,
+    /// then nullptr is returned.
+    /// \param widget Widget annotation
+    const PDFFormField* getFormFieldForWidget(PDFObjectReference widget) const;
+
     /// Parses form from the object. If some error occurs
     /// then empty form is returned, no exception is thrown.
-    /// \param storage Storage
+    /// \param document Document
     /// \param reference Field reference
-    static PDFForm parse(const PDFObjectStorage* storage, PDFObject object);
+    static PDFForm parse(const PDFDocument* document, PDFObject object);
 
 private:
+    void updateWidgetToFormFieldMapping();
+
     FormType m_formType = FormType::None;
     PDFFormFields m_formFields;
     bool m_needAppearances = false;
@@ -345,6 +355,7 @@ private:
     std::optional<QByteArray> m_defaultAppearance;
     std::optional<PDFInteger> m_quadding;
     PDFObject m_xfa;
+    PDFWidgetToFormFieldMapping m_widgetToFormField;
 };
 
 /// Form manager. Manages all form widgets functionality - triggers actions,
@@ -375,7 +386,7 @@ public:
     /// Returns form field for widget. If widget doesn't have attached form field,
     /// then nullptr is returned.
     /// \param widget Widget annotation
-    const PDFFormField* getFormFieldForWidget(PDFObjectReference widget) const;
+    const PDFFormField* getFormFieldForWidget(PDFObjectReference widget) const { return m_form.getFormFieldForWidget(widget); }
 
     PDFAnnotationManager* getAnnotationManager() const;
     void setAnnotationManager(PDFAnnotationManager* annotationManager);
@@ -391,14 +402,12 @@ public:
 
 private:
     void updateFieldValues();
-    void updateWidgetToFormFieldMapping();
 
     PDFDrawWidgetProxy* m_proxy;
     PDFAnnotationManager* m_annotationManager;
     const PDFDocument* m_document;
     FormAppearanceFlags m_flags;
     PDFForm m_form;
-    PDFWidgetToFormFieldMapping m_widgetToFormField;
 };
 
 }   // namespace pdf

PdfForQtViewer/PdfForQtViewer.pro

@@ -42,6 +42,7 @@ SOURCES += \
         pdfsendmail.cpp \
         pdfsidebarwidget.cpp \
         pdftexttospeech.cpp \
+        pdfundoredomanager.cpp \
         pdfviewermainwindow.cpp \
         pdfviewersettings.cpp \
         pdfviewersettingsdialog.cpp
@@ -55,6 +56,7 @@ HEADERS += \
         pdfsendmail.h \
         pdfsidebarwidget.h \
         pdftexttospeech.h \
+        pdfundoredomanager.h \
         pdfviewermainwindow.h \
         pdfviewersettings.h \
         pdfviewersettingsdialog.h

PdfForQtViewer/pdfforqtviewer.qrc

@@ -44,5 +44,7 @@
         <file>resources/screenshot-tool.svg</file>
         <file>resources/extract-image.svg</file>
         <file>resources/form-settings.svg</file>
+        <file>resources/undo.svg</file>
+        <file>resources/redo.svg</file>
     </qresource>
 </RCC>

PdfForQtViewer/pdfundoredomanager.cpp

@@ -0,0 +1,92 @@
+//    Copyright (C) 2020 Jakub Melka
+//
+//    This file is part of PdfForQt.
+//
+//    PdfForQt is free software: you can redistribute it and/or modify
+//    it under the terms of the GNU Lesser General Public License as published by
+//    the Free Software Foundation, either version 3 of the License, or
+//    (at your option) any later version.
+//
+//    PdfForQt is distributed in the hope that it will be useful,
+//    but WITHOUT ANY WARRANTY; without even the implied warranty of
+//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//    GNU Lesser General Public License for more details.
+//
+//    You should have received a copy of the GNU Lesser General Public License
+//    along with PDFForQt.  If not, see <https://www.gnu.org/licenses/>.
+
+#include "pdfundoredomanager.h"
+
+namespace pdfviewer
+{
+
+PDFUndoRedoManager::PDFUndoRedoManager(QObject* parent) :
+    BaseClass(parent)
+{
+
+}
+
+PDFUndoRedoManager::~PDFUndoRedoManager()
+{
+
+}
+
+void PDFUndoRedoManager::doUndo()
+{
+    if (!canUndo())
+    {
+        // Undo operation can't be performed
+        return;
+    }
+
+    UndoRedoItem item = m_undoSteps.back();
+    m_undoSteps.pop_back();
+    m_redoSteps.insert(m_redoSteps.begin(), item);
+    clampUndoRedoSteps();
+
+    emit undoRedoStateChanged();
+    emit documentChangeRequest(item.document, item.flags);
+}
+
+void PDFUndoRedoManager::doRedo()
+{
+    if (!canRedo())
+    {
+        // Redo operation can't be performed
+        return;
+    }
+
+    UndoRedoItem item = m_redoSteps.front();
+    m_redoSteps.erase(m_redoSteps.begin());
+    m_undoSteps.push_back(item);
+    clampUndoRedoSteps();
+
+    emit undoRedoStateChanged();
+    emit documentChangeRequest(item.document, item.flags);
+}
+
+void PDFUndoRedoManager::clear()
+{
+    if (canUndo() || canRedo())
+    {
+        m_undoSteps.clear();
+        m_redoSteps.clear();
+        emit undoRedoStateChanged();
+    }
+}
+
+void PDFUndoRedoManager::clampUndoRedoSteps()
+{
+    if (m_undoSteps.size() > m_undoLimit)
+    {
+        // We erase from oldest steps to newest
+        m_undoSteps.erase(m_undoSteps.begin(), std::next(m_undoSteps.begin(), m_undoSteps.size() - m_undoLimit));
+    }
+    if (m_redoSteps.size() > m_redoLimit)
+    {
+        // Newest steps are erased
+        m_redoSteps.resize(m_redoLimit);
+    }
+}
+
+}   // namespace pdfviewer

PdfForQtViewer/pdfundoredomanager.h

@@ -0,0 +1,85 @@
+//    Copyright (C) 2020 Jakub Melka
+//
+//    This file is part of PdfForQt.
+//
+//    PdfForQt is free software: you can redistribute it and/or modify
+//    it under the terms of the GNU Lesser General Public License as published by
+//    the Free Software Foundation, either version 3 of the License, or
+//    (at your option) any later version.
+//
+//    PdfForQt is distributed in the hope that it will be useful,
+//    but WITHOUT ANY WARRANTY; without even the implied warranty of
+//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//    GNU Lesser General Public License for more details.
+//
+//    You should have received a copy of the GNU Lesser General Public License
+//    along with PDFForQt.  If not, see <https://www.gnu.org/licenses/>.
+
+#ifndef PDFUNDOREDOMANAGER_H
+#define PDFUNDOREDOMANAGER_H
+
+#include "pdfdocument.h"
+
+#include <QObject>
+
+namespace pdfviewer
+{
+
+/// Undo/Redo document manager, it is managing undo and redo steps,
+/// when document is modified.
+class PDFUndoRedoManager : public QObject
+{
+    Q_OBJECT
+
+private:
+    using BaseClass = QObject;
+
+public:
+    explicit PDFUndoRedoManager(QObject* parent);
+    virtual ~PDFUndoRedoManager() override;
+
+    bool canUndo() const { return !m_undoSteps.empty(); }
+    bool canRedo() const { return !m_redoSteps.empty(); }
+
+    /// Performs single undo step. If Undo action can't be performed,
+    /// then nothing happens.
+    void doUndo();
+
+    /// Performs single redo step. If Redo action can't be performed,
+    /// then nothing happens.
+    void doRedo();
+
+    /// Clears all undo/redo steps
+    void clear();
+
+signals:
+    /// This signals are emitted, when undo/redo action availability has
+    /// been changed (for example, user pressed undo/redo action)
+    void undoRedoStateChanged();
+
+    /// This signal is being emitted, when user performs undo/redo action.
+    /// Before signal is emitted, this object is in corrected state, as action
+    /// is performed.
+    /// \param document Active document
+    /// \param flags Change flags
+    void documentChangeRequest(pdf::PDFDocumentPointer document, pdf::PDFModifiedDocument::ModificationFlags flags);
+
+private:
+    /// Clamps undo/redo steps so they fit the limits
+    void clampUndoRedoSteps();
+
+    struct UndoRedoItem
+    {
+        pdf::PDFDocumentPointer document;
+        pdf::PDFModifiedDocument::ModificationFlags flags = pdf::PDFModifiedDocument::None;
+    };
+
+    size_t m_undoLimit = 0;
+    size_t m_redoLimit = 0;
+    std::vector<UndoRedoItem> m_undoSteps;
+    std::vector<UndoRedoItem> m_redoSteps;
+};
+
+}   // namespace pdfviewer
+
+#endif // PDFUNDOREDOMANAGER_H

PdfForQtViewer/pdfviewermainwindow.cpp

@@ -117,6 +117,8 @@ PDFViewerMainWindow::PDFViewerMainWindow(QWidget* parent) :
     ui->actionRotateRight->setShortcut(QKeySequence("Ctrl+Shift++"));
     ui->actionRotateLeft->setShortcut(QKeySequence("Ctrl+Shift+-"));
     ui->actionPrint->setShortcut(QKeySequence::Print);
+    ui->actionUndo->setShortcut(QKeySequence::Undo);
+    ui->actionRedo->setShortcut(QKeySequence::Redo);
 
     for (QAction* action : m_recentFileManager->getActions())
     {

PdfForQtViewer/pdfviewermainwindow.h

@@ -34,7 +34,6 @@
 #include <QFuture>
 #include <QTreeView>
 #include <QMainWindow>
-#include <QSharedPointer>
 #include <QWinTaskbarButton>
 #include <QWinTaskbarProgress>
 #include <QFutureWatcher>
@@ -147,7 +146,7 @@ private:
 
     struct AsyncReadingResult
     {
-        QSharedPointer<pdf::PDFDocument> document;
+        pdf::PDFDocumentPointer document;
         QString errorMessage;
         pdf::PDFDocumentReader::Result result = pdf::PDFDocumentReader::Result::Cancelled;
     };
@@ -157,7 +156,7 @@ private:
     PDFRecentFileManager* m_recentFileManager;
     PDFViewerSettings* m_settings;
     pdf::PDFWidget* m_pdfWidget;
-    QSharedPointer<pdf::PDFDocument> m_pdfDocument;
+    pdf::PDFDocumentPointer m_pdfDocument;
     QString m_currentFile;
     PDFSidebarWidget* m_sidebarWidget;
     QDockWidget* m_sidebarDockWidget;

PdfForQtViewer/pdfviewermainwindow.ui

@@ -112,6 +112,9 @@
     <property name="title">
      <string>Edit</string>
     </property>
+    <addaction name="actionUndo"/>
+    <addaction name="actionRedo"/>
+    <addaction name="separator"/>
     <addaction name="actionFind"/>
     <addaction name="actionFindPrevious"/>
     <addaction name="actionFindNext"/>
@@ -508,6 +511,24 @@
     <string>Display Annotations</string>
    </property>
   </action>
+  <action name="actionUndo">
+   <property name="icon">
+    <iconset resource="pdfforqtviewer.qrc">
+     <normaloff>:/resources/undo.svg</normaloff>:/resources/undo.svg</iconset>
+   </property>
+   <property name="text">
+    <string>Undo</string>
+   </property>
+  </action>
+  <action name="actionRedo">
+   <property name="icon">
+    <iconset resource="pdfforqtviewer.qrc">
+     <normaloff>:/resources/redo.svg</normaloff>:/resources/redo.svg</iconset>
+   </property>
+   <property name="text">
+    <string>Redo</string>
+   </property>
+  </action>
  </widget>
  <layoutdefault spacing="6" margin="11"/>
  <resources>

PdfForQtViewer/resources/redo.svg

@@ -0,0 +1,108 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
+<svg
+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   width="30mm"
+   height="30mm"
+   viewBox="0 0 30 30"
+   version="1.1"
+   id="svg5291"
+   inkscape:version="0.92.4 (5da689c313, 2019-01-14)"
+   sodipodi:docname="redo.svg">
+  <defs
+     id="defs5285">
+    <inkscape:perspective
+       sodipodi:type="inkscape:persp3d"
+       inkscape:vp_x="0 : 15 : 1"
+       inkscape:vp_y="0 : 1000 : 0"
+       inkscape:vp_z="30 : 15 : 1"
+       inkscape:persp3d-origin="15 : 10 : 1"
+       id="perspective5921" />
+  </defs>
+  <sodipodi:namedview
+     id="base"
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1.0"
+     inkscape:pageopacity="0.0"
+     inkscape:pageshadow="2"
+     inkscape:zoom="11.313708"
+     inkscape:cx="82.017664"
+     inkscape:cy="53.86011"
+     inkscape:document-units="mm"
+     inkscape:current-layer="layer1"
+     showgrid="false"
+     inkscape:window-width="3840"
+     inkscape:window-height="2035"
+     inkscape:window-x="-13"
+     inkscape:window-y="-13"
+     inkscape:window-maximized="1" />
+  <metadata
+     id="metadata5288">
+    <rdf:RDF>
+      <cc:Work
+         rdf:about="">
+        <dc:format>image/svg+xml</dc:format>
+        <dc:type
+           rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
+        <dc:title></dc:title>
+        <dc:creator>
+          <cc:Agent>
+            <dc:title>Jakub Melka</dc:title>
+          </cc:Agent>
+        </dc:creator>
+        <cc:license
+           rdf:resource="http://creativecommons.org/licenses/by-sa/4.0/" />
+      </cc:Work>
+      <cc:License
+         rdf:about="http://creativecommons.org/licenses/by-sa/4.0/">
+        <cc:permits
+           rdf:resource="http://creativecommons.org/ns#Reproduction" />
+        <cc:permits
+           rdf:resource="http://creativecommons.org/ns#Distribution" />
+        <cc:requires
+           rdf:resource="http://creativecommons.org/ns#Notice" />
+        <cc:requires
+           rdf:resource="http://creativecommons.org/ns#Attribution" />
+        <cc:permits
+           rdf:resource="http://creativecommons.org/ns#DerivativeWorks" />
+        <cc:requires
+           rdf:resource="http://creativecommons.org/ns#ShareAlike" />
+      </cc:License>
+    </rdf:RDF>
+  </metadata>
+  <g
+     inkscape:label="Vrstva 1"
+     inkscape:groupmode="layer"
+     id="layer1"
+     transform="translate(0,-267)">
+    <flowRoot
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