#include <osgViewer/Viewer>
#include <osg/Texture2D>
#include <osg/State>

#include <osgDB/ReadFile>
#include <osgDB/WriteFile>
#include <osgDB/FileNameUtils>

#include <iostream>

#include <osg/GraphicsContext>

using namespace std;

int main( int argc, char **argv )
{
	if (argc < 2)
	{
		printf("Usage: %s texfiles\n", argv[0] );
		exit(1);
	}

	// create a graphics context to allow us to use OpenGL to compress textures.
	osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;
	traits->x = 1;
	traits->y = 1;
	traits->width = 1;
	traits->height = 1;
	traits->alpha = 8;
	traits->windowDecoration = false;
	traits->doubleBuffer = true;
	traits->sharedContext = 0;
	traits->pbuffer = true;

	osg::ref_ptr<osg::GraphicsContext> gfx = osg::GraphicsContext::createGraphicsContext(traits.get());
	if (!gfx || !gfx->valid())
	{
		osg::notify(osg::NOTICE)<<"Error: unable to create graphics window"<<std::endl;
		return 1;
	}

	gfx->realize();
	gfx->makeCurrent();

	for (int c=1;c<argc;c++) {
		osg::ref_ptr< osg::Image > image = osgDB::readImageFile( argv[c] );
		if (image.valid()) {
			int nc,sx,sy;
			nc = image->getPixelSizeInBits()/8;
			sx = image->s();
			sy = image->t();
			
			// Original Code
			//osg::ref_ptr< osg::State > state = new osg::State;
			
			// Robert correction
			// if valid
			osg::ref_ptr <osg::State> state = gfx->getState();
			
			osg::ref_ptr< osg::Texture2D > texture = new osg::Texture2D;
			texture->setInternalFormatMode( osg::Texture::USE_S3TC_DXT5_COMPRESSION );

			texture->setImage( image.get() );

			texture->apply( *state.get() );

			image->readImageFromCurrentTexture( 0, true );

			std::string compressedName = osgDB::getNameLessExtension( argv[c] ) + ".dds";
			osgDB::writeImageFile( *image, compressedName );
			cout<<compressedName<<" true "<<nc<<" "<<sx<<" "<<sy<<endl;
		}
		else {
			printf("Error: image not valid\n");
		}
	}
	
	return 0;
}