#include <boost/mpl/vector.hpp>
#include <boost/gil/extension/io/jpeg_dynamic_io.hpp>
//#include <boost/gil/gil_all.hpp>

#include <boost/lexical_cast.hpp>

#include <iostream>

void usage()
{
	std::cout << "Usage:\n";
	std::cout << "\t GIL_extract_channel <input_image_path> <channel_index> <output_image_path>\n";
}

namespace boost
{
	namespace gil
	{
		/// Extension a GIL pour gerer les pixels "double" ...
		typedef pixel< double, boost::gil::gray_layout_t > gray64_pixel_t;
		typedef image< gray64_pixel_t, false > gray64_image_t;
		typedef image< gray64_pixel_t, true  > gray64_planar_image_t;

		//typedef image_view< gray64_pixel_t > gray64_view_t;
	}
}

int main ( int argc , char **argv)
{
	typedef boost::mpl::vector<
		boost::gil::gray8_image_t,
		boost::gil::gray16_image_t,
		boost::gil::gray32_image_t,
		//boost::gil::gray64_image_t,
		boost::gil::rgb8_image_t,
		boost::gil::rgb16_image_t,
		boost::gil::rgb32_image_t > my_img_types;

	typedef boost::mpl::vector<
		boost::gil::gray8_view_t,
		boost::gil::gray16_view_t,
		boost::gil::gray32_view_t,
		//boost::gil::gray64_view_t,
		boost::gil::rgb8_view_t,
		boost::gil::rgb16_view_t,
		boost::gil::rgb32_view_t > my_view_types;

	if ( argc < 4 )
	{
		usage();
		return 1;
	}

	std::string input_filename( argv[1] );
	std::string output_filename( argv[3] );
	int channel_index;
	try
	{
		channel_index = boost::lexical_cast<int>( argv[2] );
	}
	catch( boost::bad_lexical_cast &e)
	{
		std::cout << "bad_lexical_cast exception : " << e.what() << std::endl;
		return 1;
	}

	boost::gil::any_image<my_img_types> runtime_image;
	boost::gil::any_image_view<my_view_types> runtime_view;

	try
	{
		boost::gil::jpeg_read_image( input_filename , runtime_image );
		runtime_view = boost::gil::nth_channel_view( const_view(runtime_image) , channel_index );
		boost::gil::jpeg_write_view( output_filename , runtime_view );
	}
	catch( std::exception &e )
	{
		std::cout << e.what() << std::endl;
		return 1;
	}

	return 0;
}