#include "main.h"
#include "data/axis.h"
#include "data/shaders.h"
#include <stdlib.h>
#include <GL/glew.h>
#include <cglm/vec3.h>
#include <cglm/vec4.h>

#define WIDTH 512
#define HEIGHT 512

unsigned char coordanate[4] = {0,1,2,3};

unsigned char palette[] =
{
	16,
	0xEB,0xD3,0xF8,0xff,
	0xEB,0xD4,0xF8,0xff,
	0xEB,0xD5,0xF8,0xff,
	0x7A,0x1C,0xAC,0xff,
};

void calc_normal(float* v1, float* v2, float* v3,float* normal, unsigned char n)
{
	vec4 lado1, lado2, lado3;
	vec4 u1, u2, u3;
	
	switch (n)
	{
	case 3:

		glm_vec3_sub(v2, v1, lado1); 
		glm_vec3_sub(v3, v1, lado2); 

		glm_vec3_cross(lado1, lado2, normal); 
		glm_vec3_normalize(normal);
		return;
	
	case 4:

        glm_vec4_sub(v2, v1, lado1); 
        glm_vec4_sub(v3, v1, lado2); 
        glm_vec4_sub(v2, v1, lado3); 
        
        glm_vec4_copy(lado1, u1);

        float alpha = glm_vec4_dot(lado2, u1) / glm_vec4_dot(u1, u1);
        vec4 proj_u1;
        glm_vec4_scale(u1, alpha, proj_u1);
        glm_vec4_sub(lado2, proj_u1, u2); 

        glm_vec4_normalize(u2);

        float beta = glm_vec4_dot(lado3, u1) / glm_vec4_dot(u1, u1);
        vec4 proj_u1_lado3;
        glm_vec4_scale(u1, beta, proj_u1_lado3);
        
        float gamma = glm_vec4_dot(lado3, u2) / glm_vec4_dot(u2, u2);
        vec4 proj_u2;
        glm_vec4_scale(u2, gamma, proj_u2);
        
        glm_vec4_sub(lado3, proj_u1_lado3, u3);
        glm_vec4_sub(u3, proj_u2, u3);
        
        glm_vec4_normalize(u3);

        glm_vec4_copy(u3, normal);
		return;
	}	
}

float * fill_normal( float * d, unsigned char m )
{
	float * n;
	n = malloc( (*d+1)*sizeof(float));
	*n = *d;
	for (int i = 0; i < *d; i += 3*m)
	{

		vec4 norm_vec;

		calc_normal((d+1)+i, (d+1)+i+m, (d+1)+i+2*m, norm_vec, m);
		glm_vec3_copy( norm_vec, (n+1)+i );
		glm_vec3_copy( norm_vec, (n+1)+i+m );
		glm_vec3_copy( norm_vec, (n+1)+i+2*m );
	}
	return n;
}

const char * wname = "manigraph: manifold grapher";
float * generate_surface();

int main( void )
{
	id_t shader, texture, shader_plain;
	mesh_t m_cube, m_axis;
	window_t window;

	if( !( window = init_window( WIDTH, HEIGHT, wname ) ) )
		goto error_window;

	use_window( window );
	set_clean_color_context( 0x2E, 0x07, 0x3F );

	glewInit(); 

	texture=create_palette_texture( palette );
	use_texture( texture );

	if( !( shader = create_shader() ) )
		goto error_shader;
	gload_program( shader, vs, VERTEX );
	gload_program( shader, fs, FRAGMENT );

	if( !( shader_plain = create_shader() ) )
		goto error_shader_plain;
	gload_program( shader_plain, vs, VERTEX );
	gload_program( shader_plain, fs_plain, FRAGMENT );

	load_fix_matrix( shader, (float)WIDTH/HEIGHT );
	load_fix_matrix( shader_plain, (float)WIDTH/HEIGHT );

	/* Fill m_cube */
	{
		float * n_cube, *d_cube;
		d_cube = generate_surface(16);
		n_cube = fill_normal( d_cube, 4 );
		if( !( m_cube = create_mesh( d_cube, n_cube, coordanate, 4 ) ) )
			goto error_mesh_cube; 
		free( n_cube );
		free( d_cube);
	}

	/* Fill m_axis */
	{
		float * n_axis;
		n_axis = fill_normal( d_axis, 3 );
		if( !( m_axis = create_mesh( d_axis, n_axis, coordanate, 3 ) ) )
			goto error_mesh_axis; 
		free( n_axis );
	}

	while( is_open_window( window ) )
	{
		quat_t q;

		q=poll_input( window );
		load_rot_matrix( shader, q );
		load_rot_matrix( shader_plain, q );
		
		clean_context();

#ifndef DEBUG
		load_mdl_matrix( shader_plain, 0, 0 );
		draw_mesh( m_axis );
		load_mdl_matrix( shader_plain, 1, 1 );
		draw_mesh( m_axis );
		load_mdl_matrix( shader_plain, 2, 2 );
		draw_mesh( m_axis );
#endif

		load_mdl_matrix( shader, 0, 3 );
		draw_mesh( m_cube );

	}

	destroy_mesh( m_axis );
	destroy_mesh( m_cube );
	destroy_shader( shader_plain );
	destroy_shader( shader );
	destroy_texture( texture );
	close_window( window );
	return 0;

error_mesh_axis:
	destroy_mesh( m_cube );
error_mesh_cube:
	destroy_shader( shader_plain );
error_shader_plain:
	destroy_shader( shader );
error_shader:
	close_window( window );
	destroy_texture( texture );
error_window:
	return 1;
}