oox: import Math objects from PPTX files

This is quite hacky and limited: in OOXML these are not OLE objects but
occur inside text boxes, and PPT 2010 allows inserting multiple Math
objects into one text box but Impress does not have as-character
anchored objects, so we can't import that properly; for now only import
Math if there is nothing else in the text box.

Also for now only import them as children of TextParagraphContext (a:p);
it's not clear what the possible parent elements could be since the
OOXML standard only lists WordProcessingML parent elements :(

Change-Id: I847f810084c9ddae4b60f93896fb73a742683cc2

1 files changed, 91 insertions, 1 deletions

diff --git a/oox/source/mathml/import.cxx b/oox/source/mathml/import.cxx
index bf49de250973..5b80dc4e7b06 100644
--- a/oox/source/mathml/import.cxx
+++ b/oox/source/mathml/import.cxx
@@ -9,6 +9,14 @@
 
 #include "oox/mathml/import.hxx"
 
+#include <oox/mathml/importutils.hxx>
+#include <oox/core/contexthandler.hxx>
+
+#include <drawingml/textparagraph.hxx>
+
+
+using namespace ::com::sun::star;
+
 namespace oox
 {
 
@@ -16,6 +24,88 @@ FormulaImportBase::FormulaImportBase()
 {
 }
 
-} // namespace
+namespace formulaimport {
+
+class LazyMathBufferingContext : public core::ContextHandler
+{
+private:
+    XmlStreamBuilder & m_rBuilder;
+    long m_Counter;
+
+public:
+    LazyMathBufferingContext(core::ContextHandler const& rParent,
+            drawingml::TextParagraph & rPara);
+
+    // com.sun.star.xml.sax.XFastContextHandler interface ---------------------
+
+    virtual void SAL_CALL startFastElement(::sal_Int32 Element, const uno::Reference<xml::sax::XFastAttributeList>& xAttribs) throw (xml::sax::SAXException, uno::RuntimeException, std::exception) override;
+    virtual void SAL_CALL endFastElement(::sal_Int32 Element) throw (xml::sax::SAXException, uno::RuntimeException, std::exception) override;
+    virtual uno::Reference< xml::sax::XFastContextHandler> SAL_CALL createFastChildContext(::sal_Int32 Element, const uno::Reference<xml::sax::XFastAttributeList >& xAttribs) throw (xml::sax::SAXException, uno::RuntimeException, std::exception) override;
+    virtual void SAL_CALL characters(const OUString& rChars) throw (xml::sax::SAXException, uno::RuntimeException, std::exception) override;
+
+};
+
+LazyMathBufferingContext::LazyMathBufferingContext(
+        core::ContextHandler const& rParent, drawingml::TextParagraph & rPara)
+    : core::ContextHandler(rParent)
+    , m_rBuilder(rPara.GetMathXml())
+    , m_Counter(0)
+{
+}
+
+void SAL_CALL LazyMathBufferingContext::startFastElement(
+        sal_Int32 const nElement,
+        uno::Reference<xml::sax::XFastAttributeList> const& xAttrs)
+    throw (xml::sax::SAXException, uno::RuntimeException, std::exception)
+{
+    if (0 < m_Counter) // ignore a14:m
+    {   // ignore outer oMathPara
+        if (1 != m_Counter || OOX_TOKEN(officeMath, oMathPara) != nElement)
+        {
+            m_rBuilder.appendOpeningTag(nElement, xAttrs);
+        }
+    }
+    ++m_Counter;
+}
+
+void SAL_CALL LazyMathBufferingContext::endFastElement(sal_Int32 const nElement)
+    throw (xml::sax::SAXException, uno::RuntimeException, std::exception)
+{
+    --m_Counter;
+    if (0 < m_Counter) // ignore a14:m
+    {   // ignore outer oMathPara
+        if (1 != m_Counter || OOX_TOKEN(officeMath, oMathPara) != nElement)
+        {
+            m_rBuilder.appendClosingTag(nElement);
+        }
+    }
+}
+
+uno::Reference<xml::sax::XFastContextHandler> SAL_CALL
+LazyMathBufferingContext::createFastChildContext(sal_Int32 const,
+        uno::Reference<xml::sax::XFastAttributeList> const&)
+    throw (xml::sax::SAXException, uno::RuntimeException, std::exception)
+{
+    return this;
+}
+
+void SAL_CALL LazyMathBufferingContext::characters(OUString const& rChars)
+    throw (xml::sax::SAXException, uno::RuntimeException, std::exception)
+{
+    if (0 < m_Counter) // ignore a14:m
+    {
+        m_rBuilder.appendCharacters(rChars);
+    }
+}
+
+} // namespace formulaimport
+
+core::ContextHandlerRef CreateLazyMathBufferingContext(
+        core::ContextHandler const& rParent, drawingml::TextParagraph & rPara)
+{
+    return new formulaimport::LazyMathBufferingContext(rParent, rPara);
+}
+
+} // namespace oox
 
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