Ref T259, Ref T243 timestamp utility functions

src/blackmisc/timestampbased.h

@@ -46,6 +46,9 @@ namespace BlackMisc
         //! Timestamp as ms value
         qint64 getMSecsSinceEpoch() const { return m_timestampMSecsSinceEpoch; }
 
+        //! Time difference in ms
+        qint64 getTimeDifferenceMs(qint64 compareTime) const { return compareTime - this->getMSecsSinceEpoch(); }
+
         //! Set to null
         void setTimestampToNull();
 
@@ -170,6 +173,9 @@ namespace BlackMisc
         //! Timestamp with offset added for interpolation
         qint64 getAdjustedMSecsSinceEpoch() const { return this->getMSecsSinceEpoch() + this->getTimeOffsetMs(); }
 
+        //! Time difference in ms (this -> compare)
+        qint64 getAdjustedTimeDifferenceMs(qint64 compareTime) const { return this->getAdjustedMSecsSinceEpoch() - compareTime; }
+
         //! Timestamp and offset
         QString getTimestampAndOffset(bool formatted) const;
 

src/blackmisc/timestampobjectlist.cpp

@@ -102,6 +102,17 @@ namespace BlackMisc
         });
     }
 
+    template<class OBJ, class CONTAINER>
+    OBJ ITimestampObjectList<OBJ, CONTAINER>::findClosestTimeDistance(qint64 msSinceEpoch) const
+    {
+        if (this->container().isEmpty()) { return OBJ(); }
+        const auto closest = std::min_element(this->container().cbegin(), this->container().cend(), [ = ](const ITimestampBased & a, const ITimestampBased & b)
+        {
+            return qAbs(a.getTimeDifferenceMs(msSinceEpoch)) < qAbs(b.getTimeDifferenceMs(msSinceEpoch));
+        });
+        return *closest;
+    }
+
     template <class OBJ, class CONTAINER>
     bool ITimestampObjectList<OBJ, CONTAINER>::hasInvalidTimestamps() const
     {
@@ -377,6 +388,17 @@ namespace BlackMisc
         return true;
     }
 
+    template<class OBJ, class CONTAINER>
+    OBJ ITimestampWithOffsetObjectList<OBJ, CONTAINER>::findClosestTimeDistanceAdjusted(qint64 msSinceEpoch) const
+    {
+        if (this->container().isEmpty()) { return OBJ(); }
+        const auto closest = std::min_element(this->container().cbegin(), this->container().cend(), [ = ](const ITimestampWithOffsetBased & a, const ITimestampWithOffsetBased & b)
+        {
+            return qAbs(a.getAdjustedTimeDifferenceMs(msSinceEpoch)) < qAbs(b.getAdjustedTimeDifferenceMs(msSinceEpoch));
+        });
+        return *closest;
+    }
+
     // see here for the reason of thess forward instantiations
     // https://isocpp.org/wiki/faq/templates#separate-template-fn-defn-from-decl
     //! \cond PRIVATE

src/blackmisc/timestampobjectlist.h

@@ -47,6 +47,9 @@ namespace BlackMisc
         //! Objects without valid timestamp
         CONTAINER findInvalidTimestamps() const;
 
+        //! Find closest (or default)
+        OBJ findClosestTimeDistance(qint64 msSinceEpoch) const;
+
         //! Has invalid timestamp
         bool hasInvalidTimestamps() const;
 
@@ -146,7 +149,10 @@ namespace BlackMisc
         //! \remark all object must have a valid timestamp
         bool isSortedAdjustedLatestFirst() const;
 
-    protected:
+        //! Closest adjusted time difference
+        OBJ findClosestTimeDistanceAdjusted(qint64 msSinceEpoch) const;
+
+protected:
         //! Constructor
         ITimestampWithOffsetObjectList();
     };