//=================================================================================================
/*!
//  \file blaze/math/traits/RowTrait.h
//  \brief Header file for the row trait
//
//  Copyright (C) 2013 Klaus Iglberger - All Rights Reserved
//
//  This file is part of the Blaze library. You can redistribute it and/or modify it under
//  the terms of the New (Revised) BSD License. Redistribution and use in source and binary
//  forms, with or without modification, are permitted provided that the following conditions
//  are met:
//
//  1. Redistributions of source code must retain the above copyright notice, this list of
//     conditions and the following disclaimer.
//  2. Redistributions in binary form must reproduce the above copyright notice, this list
//     of conditions and the following disclaimer in the documentation and/or other materials
//     provided with the distribution.
//  3. Neither the names of the Blaze development group nor the names of its contributors
//     may be used to endorse or promote products derived from this software without specific
//     prior written permission.
//
//  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
//  EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
//  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
//  SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
//  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
//  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
//  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
//  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
//  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
//  DAMAGE.
*/
//=================================================================================================

#ifndef _BLAZE_MATH_TRAITS_ROWTRAIT_H_
#define _BLAZE_MATH_TRAITS_ROWTRAIT_H_


//*************************************************************************************************
// Includes
//*************************************************************************************************

#include <blaze/util/InvalidType.h>
#include <blaze/util/mpl/If.h>
#include <blaze/util/mpl/Or.h>
#include <blaze/util/typetraits/IsConst.h>
#include <blaze/util/typetraits/IsReference.h>
#include <blaze/util/typetraits/IsVolatile.h>
#include <blaze/util/typetraits/RemoveCV.h>
#include <blaze/util/typetraits/RemoveReference.h>


namespace blaze {

//=================================================================================================
//
//  CLASS DEFINITION
//
//=================================================================================================

//*************************************************************************************************
/*!\brief Base template for the RowTrait class.
// \ingroup math_traits
//
// \section rowtrait_general General
//
// The RowTrait class template offers the possibility to select the resulting data type when
// creating a view on a specific row of a dense or sparse matrix. RowTrait defines the nested
// type \a Type, which represents the resulting data type of the row operation. In case the
// given data type is not a dense or sparse matrix type, the resulting data type \a Type is
// set to \a INVALID_TYPE. Note that \a const and \a volatile qualifiers and reference modifiers
// are generally ignored.
//
// Per default, the RowTrait template only supports the following matrix types:
//
// <ul>
//    <li>blaze::StaticMatrix</li>
//    <li>blaze::DynamicMatrix</li>
//    <li>blaze::CompressedMatrix</li>
// </ul>
//
//
// \section rowtrait_specializations Creating custom specializations
//
// It is possible to specialize the RowTrait template for additional user-defined matrix types.
// The following example shows the according specialization for the DynamicMatrix class template:

   \code
   template< typename T1, bool SO >
   struct RowTrait< DynamicMatrix<T1,SO> >
   {
      typedef DynamicVector<T1,true>  Type;
   };
   \endcode

// \n \section rowtrait_examples Examples
//
// The following example demonstrates the use of the RowTrait template, where depending on
// the given matrix type the resulting row type is selected:

   \code
   using blaze::rowMajor;
   using blaze::columnMajor;

   // Definition of the row type of a row-major dynamic matrix
   typedef blaze::DynamicMatrix<int,rowMajor>    MatrixType1;
   typedef typename RowTrait<MatrixType1>::Type  RowType1;

   // Definition of the row type of the column-major static matrix
   typedef blaze::StaticMatrix<int,3UL,3UL,columnMajor>  MatrixType2;
   typedef typename RowTrait<MatrixType2>::Type          RowType2;
   \endcode
*/
template< typename MT >  // Type of the matrix
struct RowTrait
{
 private:
   //**********************************************************************************************
   /*! \cond BLAZE_INTERNAL */
   struct Failure { typedef INVALID_TYPE  Type; };
   /*! \endcond */
   //**********************************************************************************************

   //**********************************************************************************************
   /*! \cond BLAZE_INTERNAL */
   typedef typename RemoveReference< typename RemoveCV<MT>::Type >::Type  Tmp;
   /*! \endcond */
   //**********************************************************************************************

 public:
   //**********************************************************************************************
   /*! \cond BLAZE_INTERNAL */
   typedef typename If< Or< IsConst<MT>, IsVolatile<MT>, IsReference<MT> >
                      , RowTrait<Tmp>, Failure >::Type::Type  Type;
   /*! \endcond */
   //**********************************************************************************************
};
//*************************************************************************************************

} // namespace blaze

#endif
