#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/logging.hh>
#include <nv/logger.hh>
#include <nv/math.hh>
#include <nv/string.hh>
#include <nv/types.hh>
#include <nv/interface/mesh.hh>

const nv::uint16 size_x  = 16;
const nv::uint16 size_y  = 16;
const nv::uint16 size_xy = size_x * size_y;

static nv::uint8 height[size_xy] = 
{
	4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,
	4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,
	4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,
	4,  4,  4,  6,  6,  6,  6,  6,  6,  6,  4,  4,  4,  4,  4,  4,
	4,  4,  4,  6,  6,  6,  6,  6,  6,  6,  4,  4,  4,  4,  4,  4,
	4,  4,  4,  6,  6,  6,  6,  6,  6,  6,  4,  4,  4,  4,  4,  4,
	4,  4,  4,  5,  5,  5,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,
	4,  4,  4,  5,  5,  5,  4,  2,  2,  2,  2,  2,  2,  4,  4,  4,
	4,  4,  4,  5,  5,  5,  4,  2,  2,  2,  2,  2,  2,  4,  4,  4,
	4,  4,  4,  4,  4,  4,  4,  2,  2,  2,  2,  2,  2,  4,  4,  4,
	4,  4,  4,  4,  4,  4,  4,  2,  2,  2,  2,  2,  2,  4,  4,  4,
	4,  4,  4,  4,  4,  4,  4,  2,  2,  2,  2,  2,  2,  4,  4,  4,
	4,  4,  4,  4,  4,  4,  4,  2,  2,  2,  4,  4,  4,  4,  4,  4,
	4,  4,  4,  4,  4,  4,  4,  2,  2,  2,  4,  4,  4,  4,  4,  4,
	4,  4,  4,  4,  4,  4,  4,  2,  2,  2,  4,  4,  4,  4,  4,  4,
	4,  4,  4,  4,  4,  4,  4,  2,  2,  2,  4,  4,  4,  4,  4,  4,
};

static nv::uint8 map[size_xy] = 
{
	2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  6,  6,  6,  6,  6,  6,  2,  2,  2,
	3,  2,  2,  2,  2,  2,  2,  6,  6,  6,  6,  6,  6,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  6,  6,  6,  6,  6,  6,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  6,  6,  6,  6,  6,  6,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  6,  6,  6,  6,  6,  6,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  6,  6,  6,  2,  2,  2,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  6,  6,  6,  2,  2,  2,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  6,  6,  6,  2,  2,  2,  2,  2,  2,
	2,  2,  2,  2,  2,  2,  2,  6,  6,  6,  2,  2,  2,  2,  2,  2,
};

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

	nv::program* m_char_program;
	nv::program* m_box_program;
	nv::vertex_array* m_char_va;
	nv::vertex_array* m_box_va;
	unsigned int m_count;
};

application::application()
{
	m_device = new nv::gl_device();
	m_window = m_device->create_window( 800, 600 );
	
	nv::image_data* sprites = m_device->create_image_data( "spritesheet.png" );
	nv::sampler sampler( nv::sampler::NEAREST, nv::sampler::REPEAT );
	m_texture = m_device->create_texture2d( sprites->get_size(), nv::RGBA, nv::UBYTE, sampler, (void*)sprites->get_data() );
	delete sprites;

	m_clear_state.buffers = nv::clear_state::COLOR_AND_DEPTH_BUFFER;
	m_render_state.depth_test.enabled = true;
	m_render_state.blending.enabled   = true;
	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()
{
	{ // CHARACTER
		nv::mesh cmesh;
		nv::vertex_attribute<nv::i8vec3>::list& vtx = cmesh.add_attribute<nv::i8vec3>("coords")->get();
		nv::vertex_attribute<nv::i8vec3>::list& mat = cmesh.add_attribute<nv::i8vec3>("material")->get();
		int m = 16;	int x = 0; int y = 0; int h = 0;
		vtx.emplace_back( x,   h, y );  
		vtx.emplace_back( x,   h, y+1 );
		vtx.emplace_back( x+1, h, y+1 );
		vtx.emplace_back( x+1, h, y+1 );
		vtx.emplace_back( x+1, h, y );  
		vtx.emplace_back( x,   h, y );  
		mat.insert( mat.end(), 6, nv::i8vec3( m, 1, 0 ) );
		m_char_program = m_device->create_program( nv::slurp( "char.vert" ), nv::slurp( "char.frag" ) );
		m_char_va      = m_device->create_vertex_array( &cmesh, &(m_char_program->get_attributes()), nv::STATIC_DRAW );
	}

	{ // WORLD
		nv::mesh wmesh;
		nv::vertex_attribute<nv::i8vec3>::list& vtx = wmesh.add_attribute<nv::i8vec3>("coords")->get();
		nv::vertex_attribute<nv::i8vec3>::list& mat = wmesh.add_attribute<nv::i8vec3>("material")->get();

		for (int i = 0; i < size_x * size_y; ++i )
		{
			int x = i % size_x;
			int y = i / size_x;

			vtx.emplace_back( x,   height[i], y   ); 
			vtx.emplace_back( x,   height[i], y+1 ); 
			vtx.emplace_back( x+1, height[i], y+1 ); 
			vtx.emplace_back( x+1, height[i], y+1 ); 
			vtx.emplace_back( x+1, height[i], y );   
			vtx.emplace_back( x,   height[i], y );   
			mat.insert( mat.end(), 6, nv::i8vec3( map[i], 2, 0 ) );

			if (i > 0 && height[i-1] != height[i])
			{
				short dir   = height[i-1] > height[i] ? -1 : 1;
				nv::uint8 m = 1;
				for ( int h = height[i-1]; h != height[i]; h = h + dir )
				{
					m_count += 6;
					vtx.emplace_back( x, h,     y );   
					vtx.emplace_back( x, h,     y+1 ); 
					vtx.emplace_back( x, h+dir, y+1 ); 
					vtx.emplace_back( x, h+dir, y+1 ); 
					vtx.emplace_back( x, h+dir, y );   
					vtx.emplace_back( x, h,     y );   
					mat.insert( mat.end(), 6, nv::i8vec3( m, -dir, 0 ) );
				}
			}

			if (i >= size_x && height[i-size_x] != height[i])
			{
				short dir   = height[i-size_x] > height[i] ? -1 : 1;
				nv::uint8 m = 1;
				for ( int h = height[i-size_x]; h != height[i]; h = h + dir )
				{
					vtx.emplace_back( x,   h,     y ); 
					vtx.emplace_back( x,   h+dir, y ); 
					vtx.emplace_back( x+1, h+dir, y ); 

					vtx.emplace_back( x+1, h+dir, y ); 
					vtx.emplace_back( x+1, h,     y ); 
					vtx.emplace_back( x,   h,     y ); 
					mat.insert( mat.end(), 6, nv::i8vec3( m, -3*dir, 0 ) );
				}
			}

		}

		m_count       = vtx.size();
		m_box_program = m_device->create_program( nv::slurp( "box.vert" ), nv::slurp( "box.frag" ) );
		m_box_va      = m_device->create_vertex_array( &wmesh, &(m_box_program->get_attributes()), nv::STATIC_DRAW );
	}

	return true;
}

bool application::run()
{
	int keypress = 0;

	glm::vec3 move( 0, 0, 0 );

	while(!keypress) 
	{
		m_window->get_context()->clear( m_clear_state );

		glm::mat4 model = glm::translate(glm::mat4(1.0f), glm::vec3(-8.5, 0.0, -8.0));
		glm::mat4 view  = glm::lookAt(glm::vec3(0.0, 20.0, 5.0) + move, glm::vec3(0.0, 4.0, 0.0) + move, glm::vec3(0.0, 1.0, 0.0));
		glm::mat4 projection = glm::perspective(25.0f, 1.0f*800.0f/600.0f, 0.1f, 100.0f);
		glm::mat4 mv         = view * model;

		m_texture->bind( 0 );
		m_box_program->set_uniform( "matrix_mvp", projection * mv );
		m_box_program->set_uniform( "light", glm::vec3(8.5, 4.5, 6.5) + move );
		m_box_program->set_uniform( "tex", 0 );
		m_window->get_context()->draw( nv::TRIANGLES, m_render_state, m_box_program, m_box_va, m_count );

		m_char_program->set_uniform( "matrix_mvp", projection * mv );
		m_char_program->set_uniform( "pos", move + glm::vec3( 8, 4.1, 6 ) );
		m_char_program->set_uniform( "tex", 0 );
		m_window->get_context()->draw( nv::TRIANGLES, m_render_state, m_char_program, m_char_va, 6 );
		m_window->swap_buffers();

		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_LEFT   : move.x = move.x - 1.0f; break;
					case nv::KEY_RIGHT  : move.x = move.x + 1.0f; break;
					case nv::KEY_UP     : move.z = move.z - 1.0f; break;
					case nv::KEY_DOWN   : move.z = move.z + 1.0f; break;
					default: break;
					}
				}
				break;
			default: break;
			}
		}
	}
	return true;
}

application::~application()
{
	delete m_char_program;
	delete m_box_program;
	delete m_char_va;
	delete m_box_va;
	delete m_texture;
	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;
}