From f739e9f544ebab02724c3ef7920cd7ca10d9213b Mon Sep 17 00:00:00 2001
From: Jakub Melka <Mgr.Jakub.Melka@gmail.com>
Date: Thu, 4 Nov 2021 20:01:30 +0100
Subject: [PATCH] XFA: xfa engine parsing template

---
 Pdf4QtLib/Pdf4QtLib.pro            |  2 +-
 Pdf4QtLib/sources/pdfform.cpp      |  2 +
 Pdf4QtLib/sources/pdfform.h        |  3 ++
 Pdf4QtLib/sources/pdfxfaengine.cpp | 83 +++++++++++++++++++++++++++++-
 Pdf4QtLib/sources/pdfxfaengine.h   |  4 ++
 5 files changed, 92 insertions(+), 2 deletions(-)

diff --git a/Pdf4QtLib/Pdf4QtLib.pro b/Pdf4QtLib/Pdf4QtLib.pro
index 218002a..3ba04c8 100644
--- a/Pdf4QtLib/Pdf4QtLib.pro
+++ b/Pdf4QtLib/Pdf4QtLib.pro
@@ -242,7 +242,7 @@ DEPENDPATH += $$Pdf4Qt_DEPENDENCIES_PATH/lcms2/include
 # ensure debug info even for RELEASE build
 CONFIG += force_debug_info
 
-QMAKE_CXXFLAGS += /std:c++latest /utf-8
+QMAKE_CXXFLAGS += /std:c++latest /utf-8 /bigobj
 QMAKE_RESOURCE_FLAGS += -threshold 0 -compress 9
 
 PdfforQt_library.files = $$DESTDIR/Pdf4QtLib.dll
diff --git a/Pdf4QtLib/sources/pdfform.cpp b/Pdf4QtLib/sources/pdfform.cpp
index 64d9e3c..8d4c854 100644
--- a/Pdf4QtLib/sources/pdfform.cpp
+++ b/Pdf4QtLib/sources/pdfform.cpp
@@ -1161,6 +1161,8 @@ void PDFFormManager::setDocument(const PDFModifiedDocument& document)
             // Just update field values
             updateFieldValues();
         }
+
+        m_xfaEngine.setDocument(document, &m_form);
     }
 }
 
diff --git a/Pdf4QtLib/sources/pdfform.h b/Pdf4QtLib/sources/pdfform.h
index 9d05f9d..0449db8 100644
--- a/Pdf4QtLib/sources/pdfform.h
+++ b/Pdf4QtLib/sources/pdfform.h
@@ -23,6 +23,7 @@
 #include "pdfannotation.h"
 #include "pdfdocumentdrawinterface.h"
 #include "pdfsignaturehandler.h"
+#include "pdfxfaengine.h"
 
 #include <QTextLayout>
 
@@ -720,6 +721,8 @@ private:
     PDFForm m_form;
     bool m_isCommitDisabled;
 
+    PDFXFAEngine m_xfaEngine;
+
     std::vector<PDFFormFieldWidgetEditor*> m_widgetEditors;
     PDFFormFieldWidgetEditor* m_focusedEditor;
     MouseGrabInfo m_mouseGrabInfo;
diff --git a/Pdf4QtLib/sources/pdfxfaengine.cpp b/Pdf4QtLib/sources/pdfxfaengine.cpp
index f2e7409..28e7ffa 100644
--- a/Pdf4QtLib/sources/pdfxfaengine.cpp
+++ b/Pdf4QtLib/sources/pdfxfaengine.cpp
@@ -16,8 +16,10 @@
 //    along with PDF4QT.  If not, see <https://www.gnu.org/licenses/>.
 
 #include "pdfxfaengine.h"
+#include "pdfform.h"
 
 #include <QDomElement>
+#include <QDomDocument>
 
 #include <optional>
 
@@ -8887,10 +8889,16 @@ std::optional<XFA_variables> XFA_variables::parse(const QDomElement& element)
 class PDFXFAEngineImpl
 {
 public:
-    PDFXFAEngineImpl() = default;
+    PDFXFAEngineImpl();
+
+    void setDocument(const PDFModifiedDocument& document, PDFForm* form);
 
 private:
+    void clear();
+
     xfa::XFA_Node<xfa::XFA_template> m_template;
+    const PDFDocument* m_document;
+    PDFForm* m_form;
 };
 
 PDFXFAEngine::PDFXFAEngine() :
@@ -8904,4 +8912,77 @@ PDFXFAEngine::~PDFXFAEngine()
 
 }
 
+void PDFXFAEngine::setDocument(const PDFModifiedDocument& document, PDFForm* form)
+{
+    m_impl->setDocument(document, form);
+}
+
+PDFXFAEngineImpl::PDFXFAEngineImpl() :
+    m_document(nullptr),
+    m_form(nullptr)
+{
+
+}
+
+void PDFXFAEngineImpl::setDocument(const PDFModifiedDocument& document, PDFForm* form)
+{
+    if (m_document != document || document.hasReset())
+    {
+        m_document = document;
+
+        if (document.hasReset())
+        {
+            clear();
+
+            if (form->getFormType() == PDFForm::FormType::XFAForm)
+            {
+                try
+                {
+                    const PDFObject& xfaObject = m_document->getObject(form->getXFA());
+
+                    std::map<QByteArray, QByteArray> xfaData;
+                    if (xfaObject.isArray())
+                    {
+                        const PDFArray* xfaArrayData = xfaObject.getArray();
+                        const size_t pairCount = xfaArrayData->getCount() / 2;
+
+                        for (size_t i = 0; i < pairCount; ++i)
+                        {
+                            const PDFObject& itemName = m_document->getObject(xfaArrayData->getItem(2 * i + 0));
+                            const PDFObject& streamObject = m_document->getObject(xfaArrayData->getItem(2 * i + 1));
+
+                            if (itemName.isString() && streamObject.isStream())
+                            {
+                                xfaData[itemName.getString()] = m_document->getDecodedStream(streamObject.getStream());
+                            }
+                        }
+                    }
+                    else if (xfaObject.isStream())
+                    {
+                        xfaData["template"] = m_document->getDecodedStream(xfaObject.getStream());
+                    }
+
+                    QDomDocument document;
+                    if (document.setContent(xfaData["template"]))
+                    {
+                        m_template = xfa::XFA_template::parse(document.firstChildElement("template"));
+                    }
+                }
+                catch (PDFException)
+                {
+                    // Just clear once again - if some errorneous data
+                    // were read, we want to clear them.
+                    clear();
+                }
+            }
+        }
+    }
+}
+
+void PDFXFAEngineImpl::clear()
+{
+    // Clear the template
+    m_template = xfa::XFA_Node<xfa::XFA_template>();
+}
+
 }   // namespace pdf
diff --git a/Pdf4QtLib/sources/pdfxfaengine.h b/Pdf4QtLib/sources/pdfxfaengine.h
index aec10fd..7b74b6d 100644
--- a/Pdf4QtLib/sources/pdfxfaengine.h
+++ b/Pdf4QtLib/sources/pdfxfaengine.h
@@ -19,12 +19,14 @@
 #define PDFXFAENGINE_H
 
 #include "pdfglobal.h"
+#include "pdfdocument.h"
 
 #include <memory>
 
 namespace pdf
 {
 
+class PDFForm;
 class PDFXFAEngineImpl;
 
 class PDFXFAEngine
@@ -33,6 +35,8 @@ public:
     PDFXFAEngine();
     ~PDFXFAEngine();
 
+    void setDocument(const PDFModifiedDocument& document, PDFForm* form);
+
 private:
     std::unique_ptr<PDFXFAEngineImpl> m_impl;
 };