[API CHANGE] oox: fix import of chart date categories

Before this fix, date categories imported in oox's DataSourceContext were
stored as formatted strings according to number format code in <c:formatCode>
under the <c:cat> tree. As a result chart2 could not recognize them
as dates. This causes problems like:

* The axis that is linked to date categories cannot use the
  scaling/range-selection(min/max)/increments specs mentioned as axis
  properties. This results in distorted/unreadable chart renders w.r.t
  the date axis.

* No re-formatting is attempted as per the number format provided for axis.

This patch introduces a role qualifer argument to the XDataProvider
interface method createDataSequenceByValueArray to support categories of
date type via this method.

When exporting to oox, write date categories and format code under
<c:cat>
  <c:numRef>
    <c:numCache>

This patch also fixes some discrepancies in date axis interval
computation (auto mode) found by already existing unit tests.

Change-Id: Ibc53b0a56fdddba80ba452d5567ce98d80460ea7
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/121525
Tested-by: Jenkins
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>

5 files changed, 61 insertions, 19 deletions

diff --git a/oox/source/drawingml/chart/chartconverter.cxx b/oox/source/drawingml/chart/chartconverter.cxx
index a864aac47e47..af49c561ae51 100644
--- a/oox/source/drawingml/chart/chartconverter.cxx
+++ b/oox/source/drawingml/chart/chartconverter.cxx
@@ -116,7 +116,7 @@ void ChartConverter::createDataProvider( const Reference< XChartDocument >& rxCh
 
 Reference< XDataSequence > ChartConverter::createDataSequence(
     const Reference< XDataProvider >& rxDataProvider, const DataSequenceModel& rDataSeq,
-    const OUString& rRole )
+    const OUString& rRole, const OUString& rRoleQualifier )
 {
     Reference< XDataSequence > xDataSeq;
     if( rxDataProvider.is() )
@@ -137,7 +137,7 @@ Reference< XDataSequence > ChartConverter::createDataSequence(
                 if (!aRangeRep.isEmpty())
                 {
                     // create or add a new level to the data sequence
-                    xDataSeq = rxDataProvider->createDataSequenceByValueArray(rRole, aRangeRep);
+                    xDataSeq = rxDataProvider->createDataSequenceByValueArray(rRole, aRangeRep, rRoleQualifier);
                     if (i == 0)
                         return xDataSeq;
                 }
diff --git a/oox/source/drawingml/chart/datasourcecontext.cxx b/oox/source/drawingml/chart/datasourcecontext.cxx
index 1b64089d4281..f4660f5db708 100644
--- a/oox/source/drawingml/chart/datasourcecontext.cxx
+++ b/oox/source/drawingml/chart/datasourcecontext.cxx
@@ -99,7 +99,7 @@ void DoubleSequenceContext::onCharacters( const OUString& rChars )
             if( mnPtIndex >= 0 )
             {
                 /* Import categories as String even though it could
-                 * be values.
+                 * be values except when the format code indicates that they are dates.
                  * n#810508: xVal needs to be imported as double
                  * TODO: NumberFormat conversion, remove the check then.
                  */
@@ -118,6 +118,8 @@ void DoubleSequenceContext::onCharacters( const OUString& rChars )
                             SvNumFormatType nType;
                             pNumFrmt->PutEntry( aFormatCode, nCheckPos, nType, nKey );
                             bNoKey = (nCheckPos != 0);
+                            if (!bNoKey)
+                                mrModel.meFormatType = nType;
                         }
                         if( bNoKey )
                         {
@@ -126,13 +128,18 @@ void DoubleSequenceContext::onCharacters( const OUString& rChars )
                         else
                         {
                             double fValue = rChars.toDouble();
-                            const ::Color* pColor = nullptr;
-                            OUString aFormattedValue;
-                            // tdf#91250: use UNLIMITED_PRECISION in case of GENERAL Number Format of category axis labels
-                            if( pNumFrmt->GetStandardPrec() != SvNumberFormatter::UNLIMITED_PRECISION )
-                                pNumFrmt->ChangeStandardPrec(SvNumberFormatter::UNLIMITED_PRECISION);
-                            pNumFrmt->GetOutputString( fValue, nKey, aFormattedValue, &pColor );
-                            mrModel.maData[ mnPtIndex ] <<= aFormattedValue;
+                            if (mrModel.meFormatType == SvNumFormatType::DATE)
+                                mrModel.maData[ mnPtIndex ] <<= fValue;
+                            else
+                            {
+                                const ::Color* pColor = nullptr;
+                                OUString aFormattedValue;
+                                // tdf#91250: use UNLIMITED_PRECISION in case of GENERAL Number Format of category axis labels
+                                if( pNumFrmt->GetStandardPrec() != SvNumberFormatter::UNLIMITED_PRECISION )
+                                    pNumFrmt->ChangeStandardPrec(SvNumberFormatter::UNLIMITED_PRECISION);
+                                pNumFrmt->GetOutputString( fValue, nKey, aFormattedValue, &pColor );
+                                mrModel.maData[ mnPtIndex ] <<= aFormattedValue;
+                            }
                         }
                     }
                     else
diff --git a/oox/source/drawingml/chart/datasourceconverter.cxx b/oox/source/drawingml/chart/datasourceconverter.cxx
index 72399426538d..92cacb4286bf 100644
--- a/oox/source/drawingml/chart/datasourceconverter.cxx
+++ b/oox/source/drawingml/chart/datasourceconverter.cxx
@@ -23,6 +23,7 @@
 #include <oox/drawingml/chart/chartconverter.hxx>
 #include <oox/drawingml/chart/datasourcemodel.hxx>
 #include <oox/token/properties.hxx>
+#include <svl/zforlist.hxx>
 
 namespace oox::drawingml::chart {
 
@@ -69,7 +70,10 @@ Reference< XDataSequence > DataSequenceConverter::createDataSequence( const OUSt
             mrModel.maData.insert(std::make_pair<sal_Int32, Any>(0, Any(aTitle.makeStringAndClear())));
         }
     }
-    xDataSeq = getChartConverter().createDataSequence(getChartDocument()->getDataProvider(), mrModel, rRole);
+
+    bool bDateCategories = (mrModel.meFormatType == SvNumFormatType::DATE) && (rRole == "categories");
+    xDataSeq = getChartConverter().createDataSequence(getChartDocument()->getDataProvider(), mrModel,
+        rRole, bDateCategories ? OUString("date") : OUString(""));
 
     // set sequence role
     PropertySet aSeqProp( xDataSeq );
diff --git a/oox/source/drawingml/chart/datasourcemodel.cxx b/oox/source/drawingml/chart/datasourcemodel.cxx
index e83b6b3558a5..51514437d33d 100644
--- a/oox/source/drawingml/chart/datasourcemodel.cxx
+++ b/oox/source/drawingml/chart/datasourcemodel.cxx
@@ -18,12 +18,14 @@
  */
 
 #include <oox/drawingml/chart/datasourcemodel.hxx>
+#include <svl/zforlist.hxx>
 
 namespace oox::drawingml::chart {
 
 DataSequenceModel::DataSequenceModel() :
     mnPointCount( -1 ),
-    mnLevelCount( 1 )
+    mnLevelCount( 1 ),
+    meFormatType( SvNumFormatType::UNDEFINED )
 {
 }
 
diff --git a/oox/source/export/chartexport.cxx b/oox/source/export/chartexport.cxx
index c39f2f146681..8bbd4ecd1990 100644
--- a/oox/source/export/chartexport.cxx
+++ b/oox/source/export/chartexport.cxx
@@ -158,8 +158,9 @@ private:
 
 }
 
-static Reference< chart2::data::XLabeledDataSequence > lcl_getCategories( const Reference< chart2::XDiagram > & xDiagram )
+static Reference< chart2::data::XLabeledDataSequence > lcl_getCategories( const Reference< chart2::XDiagram > & xDiagram, bool& bHasDateCategories )
 {
+    bHasDateCategories = false;
     Reference< chart2::data::XLabeledDataSequence >  xResult;
     try
     {
@@ -182,6 +183,7 @@ static Reference< chart2::data::XLabeledDataSequence > lcl_getCategories( const
                         chart2::ScaleData aScaleData = xAxis->getScaleData();
                         if( aScaleData.Categories.is())
                         {
+                            bHasDateCategories = aScaleData.AxisType == chart2::AxisType::DATE;
                             xResult.set( aScaleData.Categories );
                             break;
                         }
@@ -220,7 +222,8 @@ static bool lcl_hasCategoryLabels( const Reference< chart2::XChartDocument >& xC
 {
     //categories are always the first sequence
     Reference< chart2::XDiagram > xDiagram( xChartDoc->getFirstDiagram());
-    Reference< chart2::data::XLabeledDataSequence > xCategories( lcl_getCategories( xDiagram ) );
+    bool bDateCategories;
+    Reference< chart2::data::XLabeledDataSequence > xCategories( lcl_getCategories( xDiagram, bDateCategories ) );
     return xCategories.is();
 }
 
@@ -2861,7 +2864,26 @@ void ChartExport::exportSeriesCategory( const Reference< chart2::data::XDataSequ
     else
     {
         // export single category axis labels
-        pFS->startElement(FSNS(XML_c, XML_strRef));
+        bool bWriteDateCategories = mbHasDateCategories && (nValueType == XML_cat);
+        OUString aNumberFormatString;
+        if (bWriteDateCategories)
+        {
+            Reference< css::chart::XAxisXSupplier > xAxisXSupp( mxDiagram, uno::UNO_QUERY );
+            if( xAxisXSupp.is())
+            {
+                Reference< XPropertySet > xAxisProp = xAxisXSupp->getXAxis();
+                if (GetProperty(xAxisProp, "NumberFormat"))
+                {
+                    sal_Int32 nKey = 0;
+                    mAny >>= nKey;
+                    aNumberFormatString = getNumberFormatCode(nKey);
+                }
+            }
+            if (aNumberFormatString.isEmpty())
+                bWriteDateCategories = false;
+        }
+
+        pFS->startElement(FSNS(XML_c, bWriteDateCategories ? XML_numRef : XML_strRef));
 
         pFS->startElement(FSNS(XML_c, XML_f));
         pFS->writeEscaped(aCellRange);
@@ -2870,7 +2892,14 @@ void ChartExport::exportSeriesCategory( const Reference< chart2::data::XDataSequ
         ::std::vector< OUString > aCategories;
         lcl_fillCategoriesIntoStringVector(xValueSeq, aCategories);
         sal_Int32 ptCount = aCategories.size();
-        pFS->startElement(FSNS(XML_c, XML_strCache));
+        pFS->startElement(FSNS(XML_c, bWriteDateCategories ? XML_numCache : XML_strCache));
+        if (bWriteDateCategories)
+        {
+            pFS->startElement(FSNS(XML_c, XML_formatCode));
+            pFS->writeEscaped(aNumberFormatString);
+            pFS->endElement(FSNS(XML_c, XML_formatCode));
+        }
+
         pFS->singleElement(FSNS(XML_c, XML_ptCount), XML_val, OString::number(ptCount));
         for (sal_Int32 i = 0; i < ptCount; i++)
         {
@@ -2881,8 +2910,8 @@ void ChartExport::exportSeriesCategory( const Reference< chart2::data::XDataSequ
             pFS->endElement(FSNS(XML_c, XML_pt));
         }
 
-        pFS->endElement(FSNS(XML_c, XML_strCache));
-        pFS->endElement(FSNS(XML_c, XML_strRef));
+        pFS->endElement(FSNS(XML_c, bWriteDateCategories ? XML_numCache : XML_strCache));
+        pFS->endElement(FSNS(XML_c, bWriteDateCategories ? XML_numRef : XML_strRef));
     }
 
     pFS->endElement( FSNS( XML_c, nValueType ) );
@@ -3025,7 +3054,7 @@ void ChartExport::InitPlotArea( )
 
     if( mbHasCategoryLabels && mxNewDiagram.is())
     {
-        Reference< chart2::data::XLabeledDataSequence > xCategories( lcl_getCategories( mxNewDiagram ) );
+        Reference< chart2::data::XLabeledDataSequence > xCategories( lcl_getCategories( mxNewDiagram, mbHasDateCategories ) );
         if( xCategories.is() )
         {
             mxCategoriesValues.set( xCategories->getValues() );