INIT: Activate EPS-Related Flags in LOGIHEAD

This commit ensures that we set the correct end-point scaling flags in
LOGIHEAD (items 17..20, zero-based indices 16..19) according to the
run's requested end-point scaling behaviour.  This in turn enables the
ResInsight postprocessor to distinguish between scaled and unscaled
saturation function curves in its "RelPerm" plot window.

Note that in order to set the correct flags and to not impact the
restart files, we've elected to copy the CreateLogiHead function here.
This incurs non-zero technical debt.  We should seek to reunify the two
implementations to the extent possible.

src/opm/output/eclipse/WriteInit.cpp

@@ -27,11 +27,13 @@
 #include <opm/io/eclipse/OutputStream.hpp>
 
 #include <opm/output/data/Solution.hpp>
+#include <opm/output/eclipse/LogiHEAD.hpp>
 #include <opm/output/eclipse/Tables.hpp>
 #include <opm/output/eclipse/WriteRestartHelpers.hpp>
 
 #include <opm/parser/eclipse/EclipseState/Eclipse3DProperties.hpp>
 #include <opm/parser/eclipse/EclipseState/EclipseState.hpp>
+#include <opm/parser/eclipse/EclipseState/EndpointScaling.hpp>
 #include <opm/parser/eclipse/EclipseState/Grid/EclipseGrid.hpp>
 #include <opm/parser/eclipse/EclipseState/Grid/GridProperties.hpp>
 #include <opm/parser/eclipse/EclipseState/Grid/GridProperty.hpp>
@@ -231,6 +233,58 @@ namespace {
         return { x.begin(), x.end() };
     }
 
+    ::Opm::RestartIO::LogiHEAD::PVTModel
+    pvtFlags(const ::Opm::Runspec& rspec, const ::Opm::TableManager& tabMgr)
+    {
+        auto pvt = ::Opm::RestartIO::LogiHEAD::PVTModel{};
+
+        const auto& phases = rspec.phases();
+
+        pvt.isLiveOil = phases.active(::Opm::Phase::OIL) &&
+            !tabMgr.getPvtoTables().empty();
+
+        pvt.isWetGas = phases.active(::Opm::Phase::GAS) &&
+            !tabMgr.getPvtgTables().empty();
+
+        pvt.constComprOil = phases.active(::Opm::Phase::OIL) &&
+            !(pvt.isLiveOil ||
+              tabMgr.hasTables("PVDO") ||
+              tabMgr.getPvcdoTable().empty());
+
+        return pvt;
+    }
+
+    ::Opm::RestartIO::LogiHEAD::SatfuncFlags
+    satfuncFlags(const ::Opm::Runspec& rspec)
+    {
+        auto flags = ::Opm::RestartIO::LogiHEAD::SatfuncFlags{};
+
+        const auto& eps = rspec.endpointScaling();
+        if (eps) {
+            flags.useEndScale       = true;
+            flags.useDirectionalEPS = eps.directional();
+            flags.useReversibleEPS  = eps.reversible();
+            flags.useAlternateEPS   = eps.threepoint();
+        }
+
+        return flags;
+    }
+
+    std::vector<bool> logihead(const ::Opm::EclipseState& es)
+    {
+        const auto& rspec   = es.runspec();
+        const auto& wsd     = rspec.wellSegmentDimensions();
+        const auto& hystPar = rspec.hysterPar();
+
+        const auto lh = ::Opm::RestartIO::LogiHEAD{}
+            .variousParam(false, false, wsd.maxSegmentedWells(), hystPar.active())
+            .pvtModel(pvtFlags(rspec, es.getTableManager()))
+            .saturationFunction(satfuncFlags(rspec))
+            ;
+
+        return lh.data();
+    }
+
     void writeInitFileHeader(const ::Opm::EclipseState&      es,
                              const ::Opm::EclipseGrid&       grid,
                              const ::Opm::Schedule&          sched,
@@ -244,10 +298,7 @@ namespace {
         }
 
         {
-            const auto lh = ::Opm::RestartIO::Helpers::
-                createLogiHead(es);
-
-            initFile.write("LOGIHEAD", lh);
+            initFile.write("LOGIHEAD", logihead(es));
         }
 
         {