adding variableWellStateIndices to MultisegmentWells

to remove the using of stdWells() in BlackoilMultiSegmentModel
The code is copied from StandardWells, better solution need to be
exploited.

opm/autodiff/BlackoilMultiSegmentModel.hpp

@@ -140,7 +140,7 @@ namespace Opm {
 
         MultisegmentWells ms_wells_;
 
-        using Base::stdWells;
+        // using Base::stdWells;
         using Base::wells;
         using Base::wellsActive;
         using Base::updatePrimalVariableFromState;

opm/autodiff/BlackoilMultiSegmentModel_impl.hpp

@@ -630,7 +630,7 @@ namespace Opm {
         V aliveWells;
         const int np = wells().number_of_phases;
         std::vector<ADB> cq_s(np, ADB::null());
-        std::vector<int> indices = stdWells().variableWellStateIndices();
+        std::vector<int> indices = msWells().variableWellStateIndices();
         SolutionState state0 = state;
         WellState well_state0 = well_state;
         makeConstantState(state0);

opm/autodiff/MultisegmentWells.cpp

@@ -234,6 +234,38 @@ namespace Opm {
         well_segment_perforation_pressure_diffs_ = grav * well_segment_perforation_depth_diffs_ * well_segment_perforation_densities;
     }
 
+
+
+
+
+    void
+    MultisegmentWells::
+    variableStateWellIndices(std::vector<int>& indices,
+                             int& next) const
+    {
+        indices[Qs] = next++;
+        indices[Bhp] = next++;
+    }
+
+
+
+
+
+    std::vector<int>
+    MultisegmentWells::
+    variableWellStateIndices() const
+    {
+        // Black oil model standard is 5 equation.
+        // For the pure well solve, only the well equations are picked.
+        std::vector<int> indices(5, -1);
+        int next = 0;
+
+        variableStateWellIndices(indices, next);
+
+        assert(next == 2);
+        return indices;
+    }
+
 } // end of namespace Opm
 
 

opm/autodiff/MultisegmentWells.hpp

@@ -163,6 +163,14 @@ namespace Opm {
             updateWellControls(const bool terminal_output,
                                WellState& xw) const;
 
+            // TODO: these code are same with the StandardWells
+            // to find a better solution later.
+            void
+            variableStateWellIndices(std::vector<int>& indices,
+                                     int& next) const;
+            std::vector<int>
+            variableWellStateIndices() const;
+
     protected:
         // TODO: probably a wells_active_ will be required here.
         const std::vector<WellMultiSegmentConstPtr> wells_multisegment_;