[API CHANGE] tdf#133423 Implement chart:regression-moving-type

Change-Id: Icb967367fbf12e5a1566b7f18ebe5e3d8a3534f0
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/110748
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>
Reviewed-by: Samuel Mehrbrodt <samuel.mehrbrodt@allotropia.de>

4 files changed, 61 insertions, 13 deletions

diff --git a/chart2/source/tools/LinearRegressionCurveCalculator.cxx b/chart2/source/tools/LinearRegressionCurveCalculator.cxx
index 9cf3492d8e8e..811381507cb6 100644
--- a/chart2/source/tools/LinearRegressionCurveCalculator.cxx
+++ b/chart2/source/tools/LinearRegressionCurveCalculator.cxx
@@ -35,13 +35,15 @@ void LinearRegressionCurveCalculator::setRegressionProperties(
     sal_Int32 /*aDegree*/,
     sal_Bool  aForceIntercept,
     double    aInterceptValue,
-    sal_Int32 aPeriod )
+    sal_Int32 aPeriod,
+    sal_Int32 /*nMovingType*/)
 {
     PolynomialRegressionCurveCalculator::setRegressionProperties(
                                             1,
                                             aForceIntercept,
                                             aInterceptValue,
-                                            aPeriod);
+                                            aPeriod,
+                                            0);
 }
 
 uno::Sequence< geometry::RealPoint2D > SAL_CALL LinearRegressionCurveCalculator::getCurveValues(
diff --git a/chart2/source/tools/MovingAverageRegressionCurveCalculator.cxx b/chart2/source/tools/MovingAverageRegressionCurveCalculator.cxx
index 7774bec02a4f..bca154047935 100644
--- a/chart2/source/tools/MovingAverageRegressionCurveCalculator.cxx
+++ b/chart2/source/tools/MovingAverageRegressionCurveCalculator.cxx
@@ -24,7 +24,10 @@
 
 #include <rtl/math.hxx>
 
+#include <com/sun/star/chart2/MovingAverageType.hpp>
+
 using namespace ::com::sun::star;
+using namespace ::com::sun::star::chart2;
 
 namespace chart
 {
@@ -47,25 +50,59 @@ void SAL_CALL MovingAverageRegressionCurveCalculator::recalculateRegression(
             aXValues, aYValues,
             RegressionCalculationHelper::isValid()));
 
-    const size_t aSize = aValues.first.size();
-
     aYList.clear();
     aXList.clear();
 
-    for( size_t i = mPeriod - 1; i < aSize; ++i )
+    switch (mnMovingType)
+    {
+        case MovingAverageType::Central:
+        {
+            sal_Int32 nCentralPeriod = (mPeriod % 2 == 0) ? (mPeriod / 2) : ((mPeriod - 1) / 2);
+            calculateValues(aValues, nCentralPeriod, false);
+            break;
+        }
+
+        case MovingAverageType::AveragedAbscissa:
+        {
+            calculateValues(aValues, mPeriod, true);
+            break;
+        }
+        case MovingAverageType::Prior:
+        default:
+        {
+            calculateValues(aValues, mPeriod, false);
+            break;
+        }
+    }
+}
+
+void MovingAverageRegressionCurveCalculator::calculateValues(
+    RegressionCalculationHelper::tDoubleVectorPair aValues, sal_Int32 nPeriod, bool bUseXAvg)
+{
+    const size_t aSize = aValues.first.size();
+    for (size_t i = nPeriod - 1; i < aSize; ++i)
     {
-        double yAvg;
-        yAvg = 0.0;
+        double xAvg = 0.0;
+        double yAvg = 0.0;
 
-        for (sal_Int32 j = 0; j < mPeriod; j++)
+        for (sal_Int32 j = 0; j < nPeriod; j++)
         {
+            xAvg += aValues.first[i - j];
             yAvg += aValues.second[i - j];
         }
-        yAvg /= mPeriod;
+        yAvg /= nPeriod;
+        xAvg /= nPeriod;
 
-        double x = aValues.first[i];
         aYList.push_back(yAvg);
-        aXList.push_back(x);
+        if (bUseXAvg)
+        {
+            aXList.push_back(xAvg);
+        }
+        else
+        {
+            double x = aValues.first[i];
+            aXList.push_back(x);
+        }
     }
 }
 
diff --git a/chart2/source/tools/RegressionCurveCalculator.cxx b/chart2/source/tools/RegressionCurveCalculator.cxx
index ba8a7423c01e..c27a47e502cd 100644
--- a/chart2/source/tools/RegressionCurveCalculator.cxx
+++ b/chart2/source/tools/RegressionCurveCalculator.cxx
@@ -72,12 +72,14 @@ void RegressionCurveCalculator::setRegressionProperties(
     sal_Int32   aDegree,
     sal_Bool    aForceIntercept,
     double      aInterceptValue,
-    sal_Int32   aPeriod )
+    sal_Int32   aPeriod,
+    sal_Int32   nMovingType )
 {
     mDegree = aDegree;
     mForceIntercept = aForceIntercept;
     mInterceptValue = aInterceptValue;
     mPeriod  = aPeriod;
+    mnMovingType = nMovingType;
 }
 
 OUString RegressionCurveCalculator::getFormattedString(
diff --git a/chart2/source/tools/RegressionCurveModel.cxx b/chart2/source/tools/RegressionCurveModel.cxx
index 649e93e2702f..0fb7662830af 100644
--- a/chart2/source/tools/RegressionCurveModel.cxx
+++ b/chart2/source/tools/RegressionCurveModel.cxx
@@ -44,7 +44,8 @@ enum
     PROPERTY_EXTRAPOLATE_BACKWARD,
     PROPERTY_FORCE_INTERCEPT,
     PROPERTY_INTERCEPT_VALUE,
-    PROPERTY_CURVE_NAME
+    PROPERTY_CURVE_NAME,
+    PROPERTY_MOVING_AVERAGE_TYPE
 };
 
 void lcl_AddPropertiesToVector(
@@ -62,6 +63,12 @@ void lcl_AddPropertiesToVector(
                 beans::PropertyAttribute::BOUND |
                 beans::PropertyAttribute::MAYBEDEFAULT );
 
+    rOutProperties.emplace_back( "MovingAverageType",
+                PROPERTY_MOVING_AVERAGE_TYPE,
+                cppu::UnoType<sal_Int32>::get(),
+                beans::PropertyAttribute::BOUND |
+                beans::PropertyAttribute::MAYBEDEFAULT );
+
     rOutProperties.emplace_back( "ExtrapolateForward",
                 PROPERTY_EXTRAPOLATE_FORWARD,
                 cppu::UnoType<double>::get(),