/*******************************************************************************
 *
 * TRIQS: a Toolbox for Research in Interacting Quantum Systems
 *
 * Copyright (C) 2011-2014 by O. Parcollet
 *
 * TRIQS is free software: you can redistribute it and/or modify it under the
 * terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later
 * version.
 *
 * TRIQS is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * TRIQS. If not, see <http://www.gnu.org/licenses/>.
 *
 ******************************************************************************/
#pragma once
#include <triqs/utility/first_include.hpp>
#include "indexmaps/cuboid/map.hpp"
#include "indexmaps/cuboid/slice.hpp"
#include "impl/indexmap_storage_pair.hpp"
#include "impl/assignment.hpp"
namespace triqs { namespace arrays {

 template <typename ValueType, int Rank, typename TraversalOrder= void, bool Borrowed = false, bool IsConst = false> class array_view;
 template <typename ValueType, int Rank, typename TraversalOrder= void> class array;

 // ---------------------- array_view  --------------------------------

#define IMPL_TYPE                                                                                                                \
 indexmap_storage_pair<indexmaps::cuboid::map<Rank,TraversalOrder>, storages::shared_block<ValueType, Borrowed>, TraversalOrder, IsConst, true, \
                       Tag::array_view>

 template <typename ValueType, int Rank, typename TraversalOrder, bool Borrowed, bool IsConst>
  class array_view: Tag::array_view, TRIQS_CONCEPT_TAG_NAME(MutableArray), public IMPL_TYPE {
   static_assert( Rank>0, " Rank must be >0");

   public:
   using indexmap_type = typename IMPL_TYPE::indexmap_type;
   using storage_type = typename IMPL_TYPE::storage_type;
   using regular_type = array<ValueType, Rank, TraversalOrder>;
   using view_type = array_view<ValueType, Rank, TraversalOrder>;
   using const_view_type = array_view<ValueType, Rank, TraversalOrder, false, true>;
   using weak_view_type = array_view<ValueType, Rank, TraversalOrder, true>;

   /// Build from an IndexMap and a storage
   template <typename S> array_view(indexmap_type const& Ind, S const& Mem) : IMPL_TYPE(Ind, Mem) {}

   /// Copy constructor
   array_view(array_view const& X) : IMPL_TYPE(X.indexmap(), X.storage()) {}

   /// Build from anything that has an indexmap and a storage compatible with this class
   template <typename ISP> array_view(const ISP& X) : IMPL_TYPE(X.indexmap(), X.storage()) {
    // to be activated
    static_assert(IsConst || (!ISP::is_const), "Cannot construct a non const view from a const one !");
   }

#ifdef TRIQS_WITH_PYTHON_SUPPORT
   /// Build from a numpy.array (X is a borrowed reference) : throws if X is not a numpy.array 
   explicit array_view (PyObject * X): IMPL_TYPE(X, false, "array_view "){}
#endif

   array_view () = delete;

   // Move
   array_view(array_view && X) { this->swap_me(X); }

   /// Swap
   friend void swap( array_view & A, array_view & B) { A.swap_me(B);}

   /// Rebind the view
   void rebind(array_view const& X) {
    this->indexmap_ = X.indexmap_;
    this->storage_ = X.storage_;
   }

   // rebind the other view, iif this is const, and the other is not.
   template <typename To, bool C = IsConst> ENABLE_IFC(C) rebind(array_view<ValueType, Rank, To, Borrowed, !IsConst> const& X) {
    this->indexmap_ = X.indexmap_;
    this->storage_ = X.storage_;
   }

   /// Assignment. The size of the array MUST match exactly, except in the empty case 
   template<typename RHS> array_view & operator=(RHS const & X) { triqs_arrays_assign_delegation(*this,X); return *this; }

   ///
   array_view & operator=(array_view const & X) { triqs_arrays_assign_delegation(*this,X); return *this; } //without this, the standard = is synthetized...

   // Move assignment not defined : will use the copy = since view must copy data

   TRIQS_DEFINE_COMPOUND_OPERATORS(array_view);
   // to forbid serialization of views...
   //template<class Archive> void serialize(Archive & ar, const unsigned int version) = delete;

   template <typename... INT> friend view_type transposed_view(array_view const& a, INT... is) {
    return transposed_view(a,  mini_vector<int, Rank>{is...});
   }

   friend view_type transposed_view(array_view const& a, mini_vector<int, Rank> const& perm) {
    return {transpose(a.indexmap_, perm), a.storage_};
   }

   friend view_type c_ordered_transposed_view(array_view const& a) {
    return transposed_view(a, a.indexmap().get_memory_layout().get_memory_positions());
   }
 };
#undef IMPL_TYPE

 template <typename ValueType, int Rank, typename TraversalOrder = void, bool Borrowed = false>
 using array_const_view = array_view<ValueType, Rank, TraversalOrder, Borrowed, true>;

 //------------------------------- array ---------------------------------------------------

#define IMPL_TYPE                                                                                                                \
 indexmap_storage_pair<indexmaps::cuboid::map<Rank,TraversalOrder>, storages::shared_block<ValueType>, TraversalOrder, false, false, Tag::array_view>

 template <typename ValueType, int Rank, typename TraversalOrder>
 class array : Tag::array, TRIQS_CONCEPT_TAG_NAME(MutableArray), public IMPL_TYPE {
  public:
  using value_type = typename IMPL_TYPE::value_type;
  using storage_type = typename IMPL_TYPE::storage_type;
  using indexmap_type = typename IMPL_TYPE::indexmap_type;
  using regular_type = array<ValueType, Rank, TraversalOrder>;
  using view_type = array_view<ValueType, Rank, TraversalOrder>;
  using const_view_type = array_view<ValueType, Rank, TraversalOrder, false, true>;
  using weak_view_type = array_view<ValueType, Rank, TraversalOrder, true>;

  /// Empty array.
  explicit array(memory_layout<Rank> ml = memory_layout<Rank>{}) : IMPL_TYPE(ml) {}

  /// From a domain
  explicit array(typename indexmap_type::domain_type const& dom, memory_layout<Rank> ml = memory_layout<Rank>{})
     : IMPL_TYPE(indexmap_type(dom, ml)) {}

#ifdef TRIQS_DOXYGEN
    /// Construction from the dimensions. NB : the number of parameters must be exactly rank (checked at compile time). 
    array (size_t I_1, .... , size_t I_rank);
#else
#define IMPL(z, NN, unused)                                \
    explicit array (BOOST_PP_ENUM_PARAMS(BOOST_PP_INC(NN), size_t I_),memory_layout<Rank> ml = memory_layout<Rank>{}): \
    IMPL_TYPE(indexmap_type(mini_vector<size_t,BOOST_PP_INC(NN)>(BOOST_PP_ENUM_PARAMS(BOOST_PP_INC(NN), I_)),ml)) {\
     static_assert(IMPL_TYPE::rank-1==NN,"array : incorrect number of variables in constructor");}
    BOOST_PP_REPEAT(ARRAY_NRANK_MAX , IMPL, nil)
#undef IMPL
#endif

    // Makes a true (deep) copy of the data. 
    array(const array & X): IMPL_TYPE(X.indexmap(),X.storage().clone()) {}

    // Move
    explicit array(array && X) { this->swap_me(X); } 

    // from a temporary storage and an indexmap. Used for reshaping a temporary array
    explicit array(typename indexmap_type::domain_type const& dom, storage_type&& sto, memory_layout<Rank> ml = memory_layout<Rank>{})
       : IMPL_TYPE(indexmap_type(dom, ml), std::move(sto)) {}

    /** 
     * Build a new array from X.domain() and fill it with by evaluating X. X can be : 
     *  - another type of array, array_view, matrix,.... (any <IndexMap, Storage> pair)
     *  - a expression : e.g. array<int> A = B+ 2*C;
     */
    template <typename T>
    array(const T& X, TYPE_ENABLE_IF(memory_layout<Rank>, ImmutableCuboidArray<T>) ml = memory_layout<Rank>{})
       : IMPL_TYPE(indexmap_type(X.domain(), ml)) {
     triqs_arrays_assign_delegation(*this, X);
    }

#ifdef TRIQS_WITH_PYTHON_SUPPORT
    ///Build from a numpy.array X (or any object from which numpy can make a numpy.array). Makes a copy.
    explicit array (PyObject * X): IMPL_TYPE(X, true, "array "){}
#endif

    // build from a init_list
    template<typename T, int R=Rank>
     array(std::initializer_list<T> const & l, typename std::enable_if<R==1>::type * dummy =0):
      IMPL_TYPE(indexmap_type(mini_vector<size_t,1>(l.size()),memory_layout<Rank>())) {
       size_t i=0;
       for (auto const & x : l) (*this)(i++) = x;
      }

    template<typename T, int R=Rank>
     array (std::initializer_list<std::initializer_list<T>> const & l, typename std::enable_if<R==2>::type * dummy =0):
      IMPL_TYPE(memory_layout<Rank>()) {
       size_t i=0,j=0; int s=-1;
       for (auto const & l1 : l) { if (s==-1) s= l1.size(); else if (s != l1.size()) TRIQS_RUNTIME_ERROR << "initializer list not rectangular !";}
       IMPL_TYPE::resize(typename IMPL_TYPE::domain_type (mini_vector<size_t,2>(l.size(),s)));
       for (auto const & l1 : l) {
	for (auto const & x : l1) { (*this)(i,j++) = x;}
	j=0; ++i;
       }
      }

    /** 
     * Resizes the array. NB : all references to the storage is invalidated.
     * Does not initialize the array by default: to resize and init, do resize(IND).init()
     */
    array & resize (const indexmaps::cuboid::domain_t<IMPL_TYPE::rank> & l) { IMPL_TYPE::resize(l); return *this; }

    /// Assignement resizes the array.  All references to the storage are therefore invalidated.
    array & operator=(const array & X) { IMPL_TYPE::resize_and_clone_data(X); return *this; }

    /// Move assignment
    array & operator=(array && X) { this->swap_me(X); return *this;}

    /// Swap
    friend void swap( array & A, array & B) { A.swap_me(B);}

    /** 
     * Assignement resizes the array (if necessary).
     * All references to the storage are therefore invalidated.
     * NB : to avoid that, do make_view(A) = X instead of A = X
     */
    template<typename RHS> 
     array & operator=(const RHS & X) { 
      static_assert(ImmutableCuboidArray<RHS>::value, "Assignment : RHS not supported");
      IMPL_TYPE::resize(X.domain());
      triqs_arrays_assign_delegation(*this,X);
      return *this; 
     }

    TRIQS_DEFINE_COMPOUND_OPERATORS(array);

    template <typename... INT> friend const_view_type transposed_view(array const& a, INT... is) {
     return transposed_view(a(), is...);
    };
    template <typename... INT> friend view_type transposed_view(array& a, INT... is) {
     return transposed_view(a(), is...);
    };

  };//array class

#undef IMPL_TYPE

 //----------------------------------------------------------------------------------

 // how to build the view type ....
 template <class V, int R, typename TraversalOrder, bool Borrowed, bool IsConst>
 struct ISPViewType<V, R, TraversalOrder, Tag::array_view, Borrowed, IsConst> {
  using type = array_view<V, R, TraversalOrder, Borrowed, IsConst>;
 };
}}//namespace triqs::arrays

// The std::swap is WRONG for a view because of the copy/move semantics of view.
// Use swap instead (the correct one, found by ADL).
namespace std {
template <typename V, typename To1, typename To2, int R, bool B1, bool B2, bool C1, bool C2>
void swap(triqs::arrays::array_view<V, R, To1, B1, C1>& a, triqs::arrays::array_view<V, R, To2, B2, C2>& b) = delete;
}

#include "./expression_template/array_algebra.hpp"