From af2a4cc6b401cc10bb870841e146f3f6c4d10218 Mon Sep 17 00:00:00 2001
From: Anthony Geay <anthony.geay@edf.fr>
Date: Tue, 21 Apr 2020 08:45:31 +0200
Subject: [PATCH] WIP

---
 src/MEDCoupling/MEDCouplingMemArray.txx     |  2 +-
 src/MEDCoupling/MEDCouplingSkyLineArray.cxx | 50 +++++++++++++++++++++
 src/MEDCoupling/MEDCouplingSkyLineArray.hxx | 21 +++++++++
 3 files changed, 72 insertions(+), 1 deletion(-)

diff --git a/src/MEDCoupling/MEDCouplingMemArray.txx b/src/MEDCoupling/MEDCouplingMemArray.txx
index 373e9201b..1c7357cb8 100755
--- a/src/MEDCoupling/MEDCouplingMemArray.txx
+++ b/src/MEDCoupling/MEDCouplingMemArray.txx
@@ -5715,7 +5715,7 @@ struct NotInRange
    * - \a this : [0, 1, 1, 2, 2, 3, 4, 4, 5, 5, 5, 11]
    * - \a return is : [0, 1, 3, 5, 6, 8, 11, 12]
    *
-   * \return a newly allocated array containing the indexed array of
+   * \return a newly allocated array containing the indexed array format of groups by same consecutive value.
    * \throw if \a this is not allocated or if \a this has not exactly one component or if number of tuples is equal to 0.
    * \sa DataArrayInt::buildUnique, MEDCouplingSkyLineArray::groupPacks
    */
diff --git a/src/MEDCoupling/MEDCouplingSkyLineArray.cxx b/src/MEDCoupling/MEDCouplingSkyLineArray.cxx
index 5fdc66fa8..28dd21de0 100755
--- a/src/MEDCoupling/MEDCouplingSkyLineArray.cxx
+++ b/src/MEDCoupling/MEDCouplingSkyLineArray.cxx
@@ -347,6 +347,56 @@ MEDCouplingSkyLineArray *MEDCouplingSkyLineArray::uniqueNotSortedByPack() const
   MCAuto<MEDCouplingSkyLineArray> ret(MEDCouplingSkyLineArray::New(retIndex,retValues));
   return ret.retn();
 }
+/*!
+ * Take as input skylinearrays containing the same number of packs ( \a this->getNumberOf ).
+ * For each packs, this method aggregates corresponding pack in \a sks.
+ * 
+ * \throw if either a lenght of not nullptr instances in \a sks is zero or if number of packs of not nullptr instances in \a sks is not the same.
+ * \return a newly allocated skyline array that is the aggregated packs of inputs
+ */
+MEDCouplingSkyLineArray *MEDCouplingSkyLineArray::AggregatePacks(const std::vector<const MEDCouplingSkyLineArray *>& sks)
+{
+  std::vector<const MEDCouplingSkyLineArray *>sksEff;
+  mcIdType nbOfPacks(std::numeric_limits<mcIdType>::max());
+  constexpr char MSG[]="MEDCouplingSkyLineArray::AggregatePacks : ";
+  for(auto sk : sks)
+  {
+    if(!sk)
+    {
+      mcIdType curNbPacks(sk->getNumberOf());
+      if(sksEff.empty())
+        nbOfPacks = curNbPacks;
+      if(nbOfPacks != curNbPacks)
+      {
+        std::ostringstream oss; oss << MSG << "first not null input ska has " << nbOfPacks << " whereas there is presence of ska with " << curNbPacks << " !";
+        throw INTERP_KERNEL::Exception(oss.str());
+      }
+      sksEff.push_back(sk);
+    }
+  }
+  if(sksEff.empty())
+  {
+    std::ostringstream oss; oss << MSG << "input vector contains no not nullptr elements !";
+    throw INTERP_KERNEL::Exception(oss.str());
+  }
+  //
+  MCAuto<DataArrayIdType> index(DataArrayIdType::New()); index->alloc(nbOfPacks+1,1);
+  mcIdType *indexPtr(index->getPointer()); *indexPtr=0;
+  std::vector<const mcIdType *> indicesIn(SkyLineArrayIndexIterator(0,&sksEff),SkyLineArrayIndexIterator(sksEff.size(),&sksEff));
+  for( mcIdType packId = 0 ; packId < nbOfPacks ; ++packId, ++indexPtr )
+  {
+    mcIdType nbOfAggPacks(0);
+    std::for_each(indicesIn.begin(),indicesIn.end(),[packId,&nbOfPacks](const mcIdType *elt) { nbOfPacks+=elt[packId]; });
+    indexPtr[1] = indexPtr[0] + nbOfAggPacks;
+  }
+  mcIdType nbOfTuplesOut(index->back());
+  MCAuto<DataArrayIdType> values(DataArrayIdType::New()); values->alloc(nbOfTuplesOut,1);
+  mcIdType *valuesPtr(values->getPointer());
+  std::vector<const mcIdType *> valuesIn(SkyLineArrayValuesIterator(0,&sksEff),SkyLineArrayValuesIterator(sksEff.size(),&sksEff));
+  //
+  MCAuto<MEDCouplingSkyLineArray> ret;
+  return ret.retn();
+}
 
 /**
  * For a 2- or 3-level SkyLine array, return a copy of the absolute pack with given identifier.
diff --git a/src/MEDCoupling/MEDCouplingSkyLineArray.hxx b/src/MEDCoupling/MEDCouplingSkyLineArray.hxx
index a56d94b9a..74a63fea7 100644
--- a/src/MEDCoupling/MEDCouplingSkyLineArray.hxx
+++ b/src/MEDCoupling/MEDCouplingSkyLineArray.hxx
@@ -109,6 +109,7 @@ namespace MEDCoupling
 
     MEDCouplingSkyLineArray *groupPacks(const DataArrayIdType *indexedPacks) const;
     MEDCouplingSkyLineArray *uniqueNotSortedByPack() const;
+    static MEDCouplingSkyLineArray *AggregatePacks(const std::vector<const MEDCouplingSkyLineArray *>& sks);
 
     void getSimplePackSafe(const mcIdType absolutePackId, std::vector<mcIdType> & pack) const;
     const mcIdType * getSimplePackSafePtr(const mcIdType absolutePackId, mcIdType & packSize) const;
@@ -141,5 +142,25 @@ namespace MEDCoupling
     MCAuto<DataArrayIdType> _values;
   };
 
+  template<typename T>
+  class SkyLineArrayGenIterator : public std::iterator< std::input_iterator_tag, const mcIdType *, mcIdType, const mcIdType **, const mcIdType *>
+  {
+    std::size_t _num = 0;
+    std::vector<const MEDCouplingSkyLineArray *> *_data = nullptr;
+  public:
+    explicit SkyLineArrayGenIterator(std::size_t num , std::vector<const MEDCouplingSkyLineArray *> *data) : _num(num),_data(data) {}
+    SkyLineArrayGenIterator<T>& operator++() { ++_num; return *this; }
+    bool operator==(const SkyLineArrayGenIterator& other) const { return _num == other._num; }
+    bool operator!=(const SkyLineArrayGenIterator& other) const { return !(*this == other); }
+    reference operator*() const { T tt; return tt((*_data)[_num]); }
+  };
+
+  struct SkyLineArrayIndexPtrFunctor { const mcIdType *operator()(const MEDCouplingSkyLineArray *ska) { return ska->getIndex(); } };
+
+  using SkyLineArrayIndexIterator = SkyLineArrayGenIterator<SkyLineArrayIndexPtrFunctor>;
+  
+  struct SkyLineArrayValuesPtrFunctor { const mcIdType *operator()(const MEDCouplingSkyLineArray *ska) { return ska->getValues(); } };
+
+  using SkyLineArrayValuesIterator = SkyLineArrayGenIterator<SkyLineArrayValuesPtrFunctor>;
 }
 # endif
-- 
2.39.2