#include <nv/common.hh>
#include <iomanip>
#include <nv/gfx/keyframed_mesh.hh>
#include <nv/interface/vertex_buffer.hh>
#include <nv/gl/gl_device.hh>
#include <nv/gfx/image.hh>
#include <nv/interface/context.hh>
#include <nv/interface/window.hh>
#include <nv/interface/program.hh>
#include <nv/interface/texture2d.hh>
#include <nv/interface/mesh_loader.hh>
#include <nv/io/c_file_system.hh>
#include <nv/formats/md5_loader.hh>
#include <nv/profiler.hh>
#include <nv/logging.hh>
#include <nv/logger.hh>
#include <nv/math.hh>
#include <nv/time.hh>
#include <nv/string.hh>
#include <nv/interface/mesh.hh>
#include <nv/gfx/skeletal_mesh.hh>
#include <glm/gtx/rotate_vector.hpp>
#include <glm/gtc/matrix_access.hpp>
#include <glm/gtx/matrix_interpolation.hpp>

class mesh_part
{
public:
	mesh_part( const std::string& path, nv::program* program, nv::window* window )
		: m_mesh( nullptr ), m_program( program ), m_loader( nullptr ), m_animation( nullptr ), m_window( window )
	{
		
		NV_PROFILE("mesh_construct");
		{
			NV_PROFILE("loader->load");
			nv::c_file_system fs;
			nv::stream* mesh_file = fs.open( path.c_str() );
			m_loader = new nv::md5_loader();
			m_loader->load( *mesh_file );
			delete mesh_file;
		}

		{
			NV_PROFILE("create_mesh");
			m_mesh = new nv::skeletal_mesh( window->get_context(), m_loader );
		}

	}

	void load_animation( const std::string& path )
	{
		delete m_animation;
		m_animation = nullptr;
		NV_PROFILE("load_animation");
		nv::c_file_system fs;
		nv::stream* anim_file = fs.open( path.c_str() );

		if ( anim_file != nullptr )
		{
			m_animation = new nv::md5_animation();
			if ( !m_animation->load_animation(*anim_file) )
			{
				delete m_animation;
				m_animation = nullptr;
			}
			m_mesh->setup_animation( m_animation );
			delete anim_file;
		}
	}

	void update( nv::uint32 ms )
	{
		m_mesh->update( ms );
	}

	void draw( nv::context* context, nv::render_state& rstate, const glm::mat4& m, const glm::mat4& v, const glm::mat4& p )
	{
 		NV_PROFILE( "mesh-draw" );
 		glm::mat4 mv = v * m;
		m_program->set_opt_uniform( "nv_m_model", m );
 		m_program->set_opt_uniform( "nv_m_modelview", mv );
		m_program->set_opt_uniform( "nv_m_view_inv", glm::inverse( v ) );
 		m_program->set_opt_uniform( "nv_m_normal", glm::transpose(glm::inverse(glm::mat3(mv))) );
		m_program->set_uniform( "matrix_mvp", p * mv );
		context->draw( rstate, m_program, m_mesh );
	}

	~mesh_part()
	{
 		delete m_mesh;
	}

private:
	nv::skeletal_mesh* m_mesh;
	nv::program*       m_program;
	nv::md5_loader*    m_loader;
	nv::md5_animation* m_animation;
	nv::window*        m_window;
};

class application
{
public:
	application();
	bool initialize();
	bool run();
	~application();
protected:
	nv::device*       m_device;
	nv::window*       m_window;
	nv::texture2d*    m_diffuse;
	nv::texture2d*    m_specular;
	nv::texture2d*    m_normal;
	nv::clear_state   m_clear_state;
	nv::render_state  m_render_state;

	mesh_part*   m_mesh;
	nv::program* m_program;
};

application::application()
{
	NV_PROFILE( "app_construct" );
	m_device = new nv::gl_device();
	m_window = m_device->create_window( 800, 600, false );

	nv::sampler sampler( nv::sampler::LINEAR, nv::sampler::REPEAT );
	nv::image_data* data = m_device->create_image_data( "data/qshambler_d.png" );
	m_diffuse  = m_device->create_texture2d( data->get_size(), nv::RGBA, nv::UBYTE, sampler, (void*)data->get_data() );
	delete data;
	data = m_device->create_image_data( "data/qshambler_s.png" );
	m_specular = m_device->create_texture2d( data->get_size(), nv::RGBA, nv::UBYTE, sampler, (void*)data->get_data() );
	delete data;

	data = m_device->create_image_data( "data/qshambler_local.png" );
	m_normal = m_device->create_texture2d( data->get_size(), nv::RGBA, nv::UBYTE, sampler, (void*)data->get_data() );
	delete data;

	m_clear_state.buffers = nv::clear_state::COLOR_AND_DEPTH_BUFFER;
	m_render_state.depth_test.enabled = true;
	m_render_state.culling.enabled    = true;
	m_render_state.culling.order      = nv::culling::CCW;
	m_render_state.blending.enabled   = false;
	m_render_state.blending.src_rgb_factor   = nv::blending::SRC_ALPHA;
	m_render_state.blending.dst_rgb_factor   = nv::blending::ONE_MINUS_SRC_ALPHA;
	m_render_state.blending.src_alpha_factor = nv::blending::SRC_ALPHA;
	m_render_state.blending.dst_alpha_factor = nv::blending::ONE_MINUS_SRC_ALPHA;
}

bool application::initialize()
{
	NV_PROFILE( "app_initialize" );
	m_program = m_device->create_program( nv::slurp( "md5.vert" ), nv::slurp( "md5.frag" ) );
	m_mesh    = new mesh_part( "data/qshambler.md5mesh", m_program, m_window );
	m_mesh->load_animation( "data/idle02.md5anim" );
	return true;
}

bool application::run()
{
	nv::profiler::pointer()->log_report(); 
	NV_PROFILE( "app_run" );
	int keypress = 0;

	glm::vec3 move( 0, 50.f, 0 );

	nv::uint32 ticks   = m_device->get_ticks();
	nv::uint32 last_ticks;
	nv::fps_counter_class< nv::system_us_timer > fps_counter;

	//m_mesh->setup_animation( 0, m_mesh->get_max_frames(), 2, true );

	while(!keypress) 
	{
		last_ticks = ticks;
		ticks      = m_device->get_ticks();
		nv::uint32 elapsed = ticks - last_ticks;
		m_mesh->update( elapsed );
		{
			NV_PROFILE( "clear" );
			m_window->get_context()->clear( m_clear_state );
		}

		glm::mat4 view;
		glm::mat4 projection;
		{
			NV_PROFILE( "update_sh" );

			glm::vec3 source( 150.0f, 0.0f, 0.0f );
			glm::vec3 eye = glm::rotate( source, (ticks / 20.f), glm::vec3( 0.0,1.0,0.0 ) );

			view       = glm::lookAt(eye + move, glm::vec3(0.0f, 0.0f, 0.0f) + move, glm::vec3(0.0, 1.0, 0.0));
			projection = glm::perspective(60.0f, 1.0f*800.0f/600.0f, 0.1f, 1000.0f);

			m_diffuse ->bind( 0 );
			m_specular->bind( 1 );
			m_normal  ->bind( 2 );
			m_program->set_opt_uniform( "nv_m_projection", projection );
			m_program->set_uniform( "light_position", glm::vec3(180.0, 180.0, 0) );
			m_program->set_uniform( "light_diffuse",  glm::vec4(0.7,0.7,0.7,1.0) );
			m_program->set_uniform( "light_specular", glm::vec4(1.0,1.0,1.0,1.0) );
			m_program->set_uniform( "diffuse", 0 );
			m_program->set_uniform( "specular", 1 );
			m_program->set_uniform( "normalmap", 2 );
		}

		{
			NV_PROFILE( "draw" );
			glm::mat4 model      = 
				glm::mat4(1.f,0.f,0.f,0.f,
				          0.f,0.f,1.f,0.f,
						  0.f,1.f,0.f,0.f,
						  0.f,0.f,0.f,1.f);

			m_mesh->draw( m_window->get_context(), m_render_state, model, view, projection );
		}

		{
			NV_PROFILE( "swap" );
			m_window->swap_buffers();
		}

		{
			NV_PROFILE( "pollevent" );
			nv::io_event event;
			while(m_window->poll_event(event)) 
			{      
				switch (event.type) 
				{
				case nv::EV_QUIT:
					keypress = 1;
					break;
				case nv::EV_KEY:
					if (event.key.pressed)
					{
						switch (event.key.code) 
						{
						case nv::KEY_ESCAPE : keypress = 1; break;
						case nv::KEY_F1 : nv::profiler::pointer()->log_report(); break;
						default: break;
						}
					}
					break;
				default: break;
				}
			}
		}
		fps_counter.tick();
	}
	return true;
}

application::~application()
{
	delete m_program;
	delete m_mesh;
	delete m_diffuse;
	delete m_window;
	delete m_device;
}


int main(int, char* [])
{
	nv::logger log(nv::LOG_TRACE);
	log.add_sink( new nv::log_file_sink("log.txt"), nv::LOG_TRACE );
	log.add_sink( new nv::log_console_sink(), nv::LOG_TRACE );
	
	NV_LOG( nv::LOG_NOTICE, "Logging started" );
	application app;
	if ( app.initialize() )
	{
		app.run();
	}
	NV_LOG( nv::LOG_NOTICE, "Logging stopped" );

	return 0;
}