Add automatic TSLength calculation and tsIndex to TimesliceMetaData (mcbm2020 unpacking)

Up to now the TS length was hardcoded for the TimesliceMetaData object. This commit adds an automatic calculation and inserts it into the stored TimesliceMetaData objects.

fles/mcbm2018/CbmMcbm2018Source.cxx

@@ -259,9 +259,26 @@ Int_t CbmMcbm2018Source::FillBuffer() {
     }    // if( 0 == tsIndex % fuTsReduction )
 
     /// Save the TimeSlice meta-data for access by higher level tasks
-    /// TODO: do not hard-code the duration here!
+    if (fTSCounter == 1) {
+      auto nMsInTs = ts.num_core_microslices();
+      if (nMsInTs > 1) {
+        // This assumes that we have a component 0 and component independent ms/ts settings!
+        auto msDescA      = ts.descriptor(0, 0);
+        auto msDescB      = ts.descriptor(0, 1);
+        auto msLength     = msDescB.idx - msDescA.idx;
+        fTSLength         = msLength * nMsInTs;
+        fTSOverlappLength = msLength * (ts.num_microslices(0) - nMsInTs);
+      } else {
+        LOG(warning)
+          << "CbmMcbm2018Source::FillBuffer() - TS 1 - Calculate "
+             "TimesliceMetaData information - single microslice timeslices -> "
+             "TS duration can not be calculated with the given method. Hence, "
+             "TimesliceMetaData duration values are filled with 0";
+      }
+    }
     new ((*fTimeSliceMetaDataArray)[fTimeSliceMetaDataArray->GetEntriesFast()])
-      TimesliceMetaData(ts.descriptor(0, 0).idx);
+      TimesliceMetaData(
+        ts.descriptor(0, 0).idx, fTSLength, fTSOverlappLength, tsIndex);
 
     return 0;
   }