/*!
	\file
	\ingroup
	\author
	\brief
	\date    2001
*/


#include "TinyGL/gl_zgl.h"
#include <stdlib.h>
#include <stdio.h>


#define X v[0]
#define Y v[1]
#define Z v[2]
#define W v[3]


GLContext *gl_ctx;


void initSharedState( GLContext *c ){
	GLSharedState *s = &c->shared_state;

	s->lists              = (GLList    **)calloc( sizeof(GLList    *), MAX_DISPLAY_LISTS       );
	s->texture_hash_table = (GLTexture **)calloc( sizeof(GLTexture *), TEXTURE_HASH_TABLE_SIZE );
	alloc_texture( c, 0 );
}

void endSharedState( GLContext *c ){
	GLSharedState *s = &c->shared_state;
	int            i;

	for( i=0; i<MAX_DISPLAY_LISTS; i++ ){
		/* TODO */
	}
	free( s->lists );
	free( s->texture_hash_table );
}


void glInit( void *zbuffer1 ){
	ZBuffer    *zbuffer = (ZBuffer *)zbuffer1;
	GLContext  *c       = (GLContext*)calloc( 1, sizeof(GLContext) );
	GLViewport *v;
	int         i;

	gl_ctx = c;

	c->zb = zbuffer;

	/* allocate GLVertex array */
	c->vertex_max = POLYGON_MAX_VERTEX;
	c->vertex     = (GLVertex*)malloc( POLYGON_MAX_VERTEX * sizeof(GLVertex) );
  
	/* viewport */
	v          = &c->viewport;
	v->xmin    = 0;
	v->ymin    = 0;
	v->xsize   = zbuffer->xsize;
	v->ysize   = zbuffer->ysize;
	v->updated = 1;

	/* shared state */
	initSharedState(c);

	/* lists */
	c->exec_flag    = 1;
	c->compile_flag = 0;
	c->print_flag   = 0;
	c->in_begin     = 0;

	/* lights */
	for(i=0;i<MAX_LIGHTS;i++) {
		GLLight *l = &c->lights[i];
		l->ambient        = gl_V4_New(0,0,0,1);
		l->diffuse        = gl_V4_New(1,1,1,1);
		l->specular       = gl_V4_New(1,1,1,1);
		l->position       = gl_V4_New(0,0,1,0);
		l->norm_position  = gl_V3_New(0,0,1);
		l->spot_direction = gl_V3_New(0,0,-1);
		l->norm_spot_direction = gl_V3_New(0,0,-1);
		l->spot_exponent  =   0;
		l->spot_cutoff    = 180;
		l->attenuation[0] =   1;
		l->attenuation[1] =   0;
		l->attenuation[2] =   0;
		l->enabled        =   0;
	}
	c->first_light          = NULL;
	c->ambient_light_model  = gl_V4_New(0.2f,0.2f,0.2f,1);
	c->local_light_model    = 0;
	c->lighting_enabled     = 0;
	c->light_model_two_side = 0;

	/* default materials */
	for(i=0;i<2;i++) {
		GLMaterial *m = &c->materials[i];
		m->emission   = gl_V4_New(0,0,0,1);
		m->ambient    = gl_V4_New(0.2f,0.2f,0.2f,1);
		m->diffuse    = gl_V4_New(0.8f,0.8f,0.8f,1);
		m->specular   = gl_V4_New(0,0,0,1);
		m->shininess  = 0;
	}
	c->current_color_material_mode = GL_FRONT_AND_BACK;
	c->current_color_material_type = GL_AMBIENT_AND_DIFFUSE;
	c->color_material_enabled      = 0;

	/* textures */
	glInitTextures( c );

	/* default state */
	c->current_color.X      = 1;
	c->current_color.Y      = 1;
	c->current_color.Z      = 1;
	c->current_color.W      = 1;
	c->longcurrent_color[0] = 65535;
	c->longcurrent_color[1] = 65535;
	c->longcurrent_color[2] = 65535;
	c->current_normal.X     = 1;
	c->current_normal.Y     = 0;
	c->current_normal.Z     = 0;
	c->current_normal.W     = 0;
	c->current_edge_flag    = 1;  
	c->current_tex_coord.X  = 0;
	c->current_tex_coord.Y  = 0;
	c->current_tex_coord.Z  = 0;
	c->current_tex_coord.W  = 1;
	c->polygon_mode_front   = GL_FILL;
	c->polygon_mode_back    = GL_FILL;
	c->current_front_face   = 0; /* 0 = GL_CCW  1 = GL_CW */
	c->current_cull_face    = GL_BACK;
	c->current_shade_model  = GL_SMOOTH;
	c->cull_face_enabled    = 0;
  
	/* clear */
	c->clear_color.v[0] = 0;
	c->clear_color.v[1] = 0;
	c->clear_color.v[2] = 0;
	c->clear_color.v[3] = 0;
	c->clear_depth      = 0;

	/* selection */
	c->render_mode     = GL_RENDER;
	c->select_buffer   = NULL;
	c->name_stack_size = 0;

	/* matrix */
	c->matrix_mode = 0;

	c->matrix_stack_depth_max[0] = MAX_MODELVIEW_STACK_DEPTH;
	c->matrix_stack_depth_max[1] = MAX_PROJECTION_STACK_DEPTH;
	c->matrix_stack_depth_max[2] = MAX_TEXTURE_STACK_DEPTH;

	for(i=0;i<3;i++) {
		c->matrix_stack    [i] = (M4*)calloc(c->matrix_stack_depth_max[i],sizeof(M4));
		c->matrix_stack_ptr[i] = c->matrix_stack[i];
	}

	glMatrixMode( GL_PROJECTION );
	glLoadIdentity();
	glMatrixMode( GL_TEXTURE );
	glLoadIdentity();
	glMatrixMode( GL_MODELVIEW );
	glLoadIdentity();

	c->matrix_model_projection_updated = 1;

	/* opengl 1.1 arrays */
	c->client_states = 0;
  
	/* opengl 1.1 polygon offset */
	c->offset_states = 0;
  
	/* clear the resize callback function pointer */
	c->gl_resize_viewport = NULL;
  
	/* specular buffer */
	c->specbuf_first        = NULL;
	c->specbuf_used_counter = 0;
	c->specbuf_num_buffers  = 0;

	/* depth test */
	c->depth_test = 0;
}

void glClose( void ){
	GLContext *c = gl_get_context();

	endSharedState( c );
	free( c );
}