/*
   render/render.cc
   This file is part of the Osirion project and is distributed under 
   the terms of the GNU General Public License version 2 
*/

#include <iostream>
#include <fstream>
#include <sstream>
#include <iomanip>

#include "auxiliary/functions.h"
#include "core/core.h"
#include "filesystem/filesystem.h"
#include "model/model.h"
#include "render/gl.h"
#include "render/dust.h"
#include "render/textures.h"
#include "render/tga.h"
#include "render/render.h"
#include "sys/sys.h"

namespace render {

core::Cvar *r_arraysize = 0;
core::Cvar *r_bbox = 0;
core::Cvar *r_grid = 0;
core::Cvar *r_radius = 0;
core::Cvar *r_sky = 0;
core::Cvar *r_wireframe = 0;
core::Cvar *screenshotformat = 0;
core::Cvar *screenshotquality = 0;

int screenshot_number = 0;

using model::VertexArray;
VertexArray *vertexarray = 0;

void func_list_textures(std::string const &args)
{
	Textures::list();
}

void reset_gl()
{
	// set clear color
	gl::clearcolor(0.0f, 0.0f, 0.0f, 1.0f);

	// load identity matrices
	gl::matrixmode(GL_MODELVIEW);
	gl::loadidentity();

	gl::matrixmode(GL_MODELVIEW);
	gl::loadidentity();

	// shading model: Gouraud (smooth, the default)
	gl::shademodel(GL_SMOOTH);
	//gl::shademodel(GL_FLAT);

	// lighting settings for the default light GL_LIGHT0
 	GLfloat light_position[] = { 0.0, 0.0, 0.0, 1.0 };
	GLfloat ambient_light[] = { 0.01f, 0.01f, 0.01f, 1.0f };
	GLfloat diffuse_light[] = { 0.2f, 0.2f, 0.2f, 1.0f };
	GLfloat specular_light[] = { 0.2f, 0.2f, 0.2f, 1.0f };
	
	glLightfv(GL_LIGHT0, GL_POSITION, light_position);
	glLightfv(GL_LIGHT0, GL_AMBIENT, ambient_light);
	glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse_light);
	glLightfv(GL_LIGHT0, GL_SPECULAR, specular_light);

	// GL_LIGHT0 is always enabled
	gl::enable(GL_LIGHT0);

	// color tracking
	glColorMaterial(GL_FRONT, GL_AMBIENT_AND_DIFFUSE);	

	// material settings	
	GLfloat specular_reflectance[] = { 0.2f, 0.2f, 0.2f, 1.0f };
	glMaterialfv(GL_FRONT, GL_SPECULAR, specular_reflectance);
	glMateriali(GL_FRONT, GL_SHININESS, 128); // shininess 1-128

	// alpha blending function
	gl::blendfunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

	gl::disable(GL_LIGHTING);
	gl::disable(GL_COLOR_MATERIAL);

	gl::cullface(GL_BACK);
	gl::frontface(GL_CCW);
	gl::disable(GL_CULL_FACE);
	gl::disable(GL_DEPTH_TEST);	
	gl::disable(GL_BLEND);	

	gl::disable(GL_TEXTURE_2D);
}

void init() 
{
	con_print << "^BInitializing renderer..." << std::endl;

	con_print << "  renderer   ^B" << gl::renderer() << std::endl;
	con_print << "  vendor     ^B" << gl::vendor() << std::endl;
	con_print << "  version    ^B" << gl::version() << std::endl;

	// size of the vertex array in megabytes
	r_arraysize = core::Cvar::get("r_arraysize", 0.0f , core::Cvar::Archive);
	r_arraysize->set_info("[int] size of the vertex array in Mb");

	size_t mb = (size_t) r_arraysize->value();
	if (mb < 4 * sizeof(float))
		mb = 4 * sizeof(float);
	if (mb > 256)
		mb = 256;
	(*r_arraysize) = (float) mb;
	vertexarray = new VertexArray(mb);

	r_radius = core::Cvar::get("r_radius", "0", core::Cvar::Archive);
	r_radius->set_info("[bool] render entity radius");

	r_wireframe = core::Cvar::get("r_wireframe", "0", core::Cvar::Archive);
	r_wireframe->set_info("[bool] render wireframe");

	r_grid = core::Cvar::get("r_grid", "0", core::Cvar::Archive);
	r_grid->set_info("[bool] render the space grid");

	r_bbox = core::Cvar::get("r_bbox", "0", core::Cvar::Archive);
	r_bbox->set_info("[bool] render model bounding box");

	r_sky = core::Cvar::get("r_sky", "1", core::Cvar::Archive);
	r_sky->set_info("[bool] render the sky globe");

	screenshotformat = core::Cvar::get("screenshotformat", "jpg", core::Cvar::Archive);
	screenshotformat->set_info("[string] screenshot format: jpg png tga");

	screenshotquality = core::Cvar::get("screenshotquality", "85", core::Cvar::Archive);
	screenshotquality->set_info("[int] screenshot jpg quality");

	reset_gl();

	Camera::init();

	Textures::init();

	Text::init();

	Dust::init();
	
	core::Func *func = core::Func::add("list_textures", func_list_textures);
	func->set_info("list loaded textures");
}

void resize(int width, int height)
{
	// setup our viewport.
	gl::viewport(0, 0, width, height);
	Camera::resize(width, height);
}

// unload game assets (zone change)
void unload()
{
	// clear zone sky textures
	for (core::Zone::Registry::iterator it = core::Zone::registry().begin(); it != core::Zone::registry().end(); it++) {
		core::Zone *zone = (*it).second;
		if (zone->sky_texture()) {
			render::Textures::unload(zone->sky_texture());
			zone->set_sky_texture(0);
		}
	}

	for (core::Entity::Registry::iterator it = core::Entity::registry().begin(); it != core::Entity::registry().end(); it++) {
		core:: Entity *entity = (*it).second;
	
		if (entity->type() == core::Entity::Globe) { 		
			core::EntityGlobe *globe = static_cast<core::EntityGlobe *>(entity);
			if (globe->render_texture) {
				render::Textures::unload(globe->render_texture);
				globe->render_texture = 0;
			}
		}
	}
}

// clear all assets
void clear()
{
	// clear zone sky textures
	for (core::Zone::Registry::iterator it = core::Zone::registry().begin(); it != core::Zone::registry().end(); it++) {
		core::Zone *zone = (*it).second;
		zone->set_sky_texture(0);
	}

	// clear entity models, and globe textures, this will force a reload
	for (core::Entity::Registry::iterator it = core::Entity::registry().begin(); it != core::Entity::registry().end(); it++) {
		core::Entity *entity = (*it).second;

		if (entity->model())
			entity->entity_model = 0;

		if (entity->type() == core::Entity::Globe) { 
			core::EntityGlobe *globe = static_cast<core::EntityGlobe *>(entity);
			globe->render_texture = 0;
		}
	}

	// clear models
	model::Model::clear();

	// clear vertex array
	delete vertexarray;
	vertexarray = 0;
}

// reset render subsystem
void reset()
{
	clear();

	Textures::shutdown();
	Textures::init();
	size_t mb = (size_t) r_arraysize->value();
	if (mb < 4 * sizeof(float))
		mb = 4 * sizeof(float);
	if (mb > 256)
		mb = 256;
	(*r_arraysize) = (float) mb;
	vertexarray = new VertexArray(mb);

	reset_gl();
	Dust::reset();
}

void shutdown()
{
	con_print << "^BShutting down renderer..." << std::endl;

	core::Func::remove("list_textures");

	clear();

	Text::shutdown();

	Textures::shutdown();

	Camera::shutdown();

	Dust::shutdown();
}


void screenshot()
{
        bool available = false;
	std::string shortname;
	std::string filename;
	const int TYPETGA = 0;
	const int TYPEPNG = 1;
	const int TYPEJPG = 2;
	int filetype = TYPETGA;

	// make sure the screenshots folder exists
	filename.assign(filesystem::writedir());
	filename.append("screenshots/");
	sys::mkdir(filename);

	aux::lowercase(screenshotformat->str());

	if ((screenshotformat->str().compare("jpg") == 0) || (screenshotformat->str().compare("jpeg") == 0)) {
		filetype = TYPEJPG;
		if (screenshotquality->value() < 10) {
			(*screenshotquality) = 10;
		} else if (screenshotquality->value() > 100) {
			(*screenshotquality) = 100;
		}

	} else if (screenshotformat->str().compare("png") == 0) {
		filetype = TYPEPNG;

	} else if (screenshotformat->str().compare("tga") == 0) {
		filetype = TYPETGA;

	} else {
		filetype = TYPETGA;
		(*screenshotformat) = "tga";
	}

        // find the first available screenshotxxxx
        do {
		std::stringstream nstr;
		nstr << screenshot_number;
		shortname.assign(nstr.str());

		while(shortname.size() < 4)
			shortname.insert(0, 1, '0');
		
                shortname.insert(0, "screenshots/osirion");
		shortname.append(".");
		shortname.append(screenshotformat->str());

		filename.assign(filesystem::writedir());
		filename.append(shortname);

                FILE *handle = fopen(filename.c_str(), "r");
                if (handle) {
                        fclose(handle);
                } else {
                        available = true;		
                }
		screenshot_number++;
        } while (!available);

	render::Image image(Camera::width(), Camera::height(), 3);

	glReadPixels(0, 0, (GLsizei) Camera::width(), (GLsizei) Camera::height(), 
		GL_RGB, GL_UNSIGNED_BYTE, (void *) image.data());

	image.flip();

	if (filetype == TYPEPNG) {
/*		if ((Camera::width() % 8 != 0 ) || (Camera::height() % 8 != 0 )) {
			image.pad();
		}*/
		render::PNG::save(filename.c_str(), image);
	} else if (filetype == TYPEJPG) {
/*		if ((Camera::width() % 8 != 0 ) || (Camera::height() % 8 != 0 )) {
			image.pad();
		}
*/
		render::JPG::save(filename.c_str(), image, (int) screenshotquality->value());
	} else if (filetype == TYPETGA) {
		render::TGA::save(filename.c_str(), image);
	}
}

}