/*
    Copyright 2007-2008 Christian Henning, Andreas Pokorny, Lubomir Bourdev
    Use, modification and distribution are subject to the Boost Software License,
    Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
    http://www.boost.org/LICENSE_1_0.txt).
*/

/*************************************************************************************************/

#ifndef BOOST_GIL_EXTENSION_IO_READ_VIEW_HPP_INCLUDED
#define BOOST_GIL_EXTENSION_IO_READ_VIEW_HPP_INCLUDED

////////////////////////////////////////////////////////////////////////////////////////
/// \file
/// \brief
/// \author Christian Henning, Andreas Pokorny, Lubomir Bourdev \n
///
/// \date   2007-2008 \n
///
////////////////////////////////////////////////////////////////////////////////////////

#include <boost/type_traits/is_base_and_derived.hpp>
#include <boost/mpl/and.hpp>
#include <boost/utility/enable_if.hpp>

#include "base.hpp"
#include "io_device.hpp"
#include "path_spec.hpp"

namespace boost{ namespace gil {

/// \ingroup IO

/// \brief Reads an image view without conversion. No memory is allocated.
/// \param file      It's a device. Must satisfy is_input_device metafunction.
/// \param view      The image view in which the data is read into.
/// \param settings  Specifies read settings depending on the image format.
/// \throw std::ios_base::failure
template < typename Device
         , typename View
         , typename FormatTag
         >
inline
void read_view( Device&                                 file
              , const View&                             view
              , const image_read_settings< FormatTag >& settings
              , typename enable_if< typename mpl::and_< typename detail::is_input_device< Device    >::type
                                                      , typename is_format_tag          < FormatTag >::type
                                                      , typename is_read_supported      < typename get_pixel_type< View >::type
                                                                                        , FormatTag
                                                                                        >::type
                                                       >::type
                                  >::type* /* ptr */ = 0
              )
{
    detail::reader< Device
                  , FormatTag
                  , detail::read_and_no_convert
                  > reader( file
                          , settings
                          );

    reader.init_view( view
                    , reader.get_info()
                    );

    reader.apply( view );
}

/// \brief Reads an image view without conversion. No memory is allocated.
/// \param file      It's a device. Must satisfy is_adaptable_input_device metafunction.
/// \param view      The image view in which the data is read into.
/// \param settings  Specifies read settings depending on the image format.
/// \throw std::ios_base::failure
template < typename Device
         , typename View
         , typename FormatTag
         >
inline
void read_view( Device&                                 file
              , const View&                             view
              , const image_read_settings< FormatTag >& settings
              , typename enable_if< typename mpl::and_< typename detail::is_adaptable_input_device< FormatTag
                                                                                                  , Device
                                                                                                  >::type
                                                      , typename is_format_tag<FormatTag>::type
                                                      , typename is_read_supported< typename get_pixel_type< View >::type
                                                                                  , FormatTag
                                                                                  >::type
                                                      >::type
                                  >::type* /* ptr */ = 0
              )
{
    typedef typename detail::is_adaptable_input_device< FormatTag
                                                      , Device
                                                      >::device_type device_type;

    device_type dev( file );

    detail::reader< device_type
                  , FormatTag
                  , detail::read_and_no_convert
                  > reader( dev
                          , settings
                          );

    reader.init_view( view
                    , reader.get_info()
                    );

    reader.apply( view );
}

/// \brief Reads an image view without conversion. No memory is allocated.
/// \param file_name File name. Must satisfy is_supported_path_spec metafunction.
/// \param view      The image view in which the data is read into.
/// \param settings  Specifies read settings depending on the image format.
/// \throw std::ios_base::failure
template < typename String
         , typename View
         , typename FormatTag
         >
inline
void read_view( const String&                           file_name
              , const View&                             view
              , const image_read_settings< FormatTag >& settings
              , typename enable_if< typename mpl::and_< typename detail::is_supported_path_spec< String >::type
                                                      , typename is_format_tag< FormatTag >::type
                                                      , typename is_read_supported< typename get_pixel_type< View >::type
                                                                                  , FormatTag
                                                                                  >::type
                                                      >::type
                                  >::type* /* ptr */ = 0
              )
{
    detail::file_stream_device<FormatTag> device( detail::convert_to_string( file_name )
                                                , typename detail::file_stream_device< FormatTag >::read_tag()
                                                );

    read_view( device
             , view
             , settings
             );
}

/// \brief Reads an image view without conversion. No memory is allocated.
/// \param file_name File name. Must satisfy is_supported_path_spec metafunction.
/// \param view      The image view in which the data is read into.
/// \param tag       Defines the image format. Must satisfy is_format_tag metafunction. 
/// \throw std::ios_base::failure
template < typename String
         , typename View
         , typename FormatTag
         >
inline
void read_view( const String&    file_name
              , const View&      view
              , const FormatTag&
              , typename enable_if< typename mpl::and_< typename detail::is_supported_path_spec< String >::type
                                                      , typename is_format_tag< FormatTag >::type
                                                      , typename is_read_supported< typename get_pixel_type< View >::type
                                                                                  , FormatTag
                                                                                  >::type
                                                      >::type
                                  >::type* /* ptr */ = 0
              )
{
    read_view( file_name
             , view
             , image_read_settings< FormatTag >()
             );
}

/// \brief Reads an image view without conversion. No memory is allocated.
/// \param file It's a device. Must satisfy is_input_device metafunction or is_adaptable_input_device.
/// \param view The image view in which the data is read into.
/// \param tag  Defines the image format. Must satisfy is_format_tag metafunction. 
/// \throw std::ios_base::failure
template< typename Device
        , typename View
        , typename FormatTag
        >
inline
void read_view( Device&          device
              , const View&      view
              , const FormatTag&
              , typename enable_if< typename mpl::and_< typename is_format_tag< FormatTag >::type
                                                      , typename mpl::or_< typename detail::is_input_device< Device >::type
                                                                         , typename detail::is_adaptable_input_device< FormatTag
                                                                                                                     , Device
                                                                                                                     >::type
                                                                         >::type
                                                      , typename is_read_supported< typename get_pixel_type< View >::type
                                                                                  , FormatTag
                                                                                  >::type
                                                      >::type
                                  >::type* /* ptr */ = 0
              )
{
    read_view( device
             , view
             , image_read_settings< FormatTag >()
             );
}

} // namespace gil
} // namespace boost

#endif // BOOST_GIL_EXTENSION_IO_READ_VIEW_HPP_INCLUDED