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

#include <stdlib.h>
#include <iostream>

#include "core/application.h"
#include "core/cvar.h"
#include "core/func.h"
#include "core/gameinterface.h"
#include "core/player.h"
#include "model/model.h"
#include "sys/sys.h"

namespace core
{

void func_list_model(std::string const &args)
{
	model::Model::list();
}

Player GameInterface::game_localplayer;

EntityControlable *localcontrol()
{ 
	if (game()->localplayer())
		return game()->localplayer()->control();
	else
		return 0;
	
}
Player *localplayer()
{ 
	return game()->localplayer();
}

GameInterface::GameInterface()
{
	clear();
	
	game_localplayer.clear();
	if (Cvar::sv_dedicated->value()) {
		game_localplayer.player_name.assign("Console");
	} else {
		game_localplayer.player_name.assign("Player");
		game_localplayer.update_info();
	}
	
	core::Func::add("list_model", (core::FuncPtr) func_list_model);
}

GameInterface::~GameInterface()
{
	core::Func::remove("list_model");

	game_localplayer.clear();

	clear();
}

// clear all game related objects
void GameInterface::clear()
{
	//con_debug << "Clearing game data\n";

	// remove all entities
	for (std::map<unsigned int, Entity*>::iterator it = Entity::registry.begin(); it != Entity::registry.end(); it++) {
		delete (*it).second;
	}
	Entity::registry.clear();

	// remove all game functions
	for (std::map<std::string, Func*>::iterator it = Func::registry.begin(); it != Func::registry.end(); it++) {
		if ( ((*it).second->flags() & Func::Game) == Func::Game) {
			delete (*it).second;
			Func::registry.erase(it);
		}
	}

	// remove all game cvars
	for (std::map<std::string, Cvar*>::iterator it = Cvar::registry.begin(); it != Cvar::registry.end(); it++) {
		if ( ((*it).second->flags() & Cvar::Game) == Cvar::Game) {
			delete (*it).second;
			Cvar::registry.erase(it);
		}
	}

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

	game_previousframetime = 0;
	game_serverframetime = 0;
	game_clientframetime = 0;
}

void GameInterface::reset_clientstate(float servertime)
{
	game_previousframetime = game_serverframetime;
	game_clientframetime = game_serverframetime;

	game_serverframetime = servertime;
	
	std::map<unsigned int, core::Entity *>::iterator it;
	for (it=core::Entity::registry.begin(); it != core::Entity::registry.end(); it++) {
		
		core::Entity *entity = (*it).second;

		if (entity->state() && !(entity->flags() & core::Entity::Static))
			entity->state()->assign(entity);
	}
}

void GameInterface::update_clientstate(float seconds)
{
	game_clientframetime += seconds;

	if (game_clientframetime > game_serverframetime)
		game_clientframetime = game_serverframetime;

	std::map<unsigned int, Entity *>::iterator it;
	for (it=Entity::registry.begin(); it != Entity::registry.end(); it++) {

		Entity *entity = (*it).second;

		// update client state
		if (!entity->state()) {
			entity->entity_clientstate = new core::ClientState(entity);
		}
		
		if (!(entity->flags() & core::Entity::Static)) {

			// clientstate location
			entity->state()->state_location = entity->state()->previouslocation() + 
			(entity->location() - entity->state()->previouslocation()) * core::game()->timeoffset();

			if (core::game()->clientframetime() < core::game()->serverframetime()) {

				// http://local.wasp.uwa.edu.au/~pbourke/geometry/planeline/
				float cosangle;
				float angle;
				float side;
				float u;

				math::Vector3f n;
				math::Vector3f p;

				// clientstate axis: pitch

				// project entity->axis().up() into the plane with entity->state()->axis()->left() normal
				n = entity->state()->axis().left();
				p = entity->axis().up();
				u = p[0]*n[0] + p[1]*n[1] + p[2]*n[2] / (-n[0]*n[0] - n[1]*n[1] - n[2] * n[2]);
				p = entity->axis().up() + u * n;
		
				side = entity->state()->axis().forward().x * p.x + 
				       entity->state()->axis().forward().y * p.y +
				       entity->state()->axis().forward().z * p.z;

				if (fabs(side) > 0.00005f) {
					cosangle = math::dotproduct(p, entity->state()->axis().up());
					
					if (fabs(cosangle) < 0.99995f) {
						angle = acos(cosangle) * 180.0f / M_PI;
						angle = math::sgnf(side) * angle * seconds / 
							(core::game()->serverframetime() - core::game()->clientframetime());

						entity->state()->state_axis.change_pitch(-angle);
					}
				}

				// clientstate axis: direction

				// project entity->axis().forward() into the plane with entity->state()->axis().up() normal
				n = entity->state()->axis().up();
				p = entity->axis().forward();
				u = p[0]*n[0] + p[1]*n[1] + p[2]*n[2] / (-n[0]*n[0] - n[1]*n[1] - n[2] * n[2]);
				p = entity->axis().forward() + u * n;

				side = entity->state()->axis().left().x * p.x + 
				       entity->state()->axis().left().y * p.y +
				       entity->state()->axis().left().z * p.z;

				if (fabs(side) > 0.00005f) {
					cosangle = math::dotproduct(p, entity->state()->axis().forward());
					if (fabs(cosangle) < 0.99995f) {
						angle = acos(cosangle) * 180.0f / M_PI;
						angle = math::sgnf(side) * angle * seconds / 
							(core::game()->serverframetime() - core::game()->clientframetime());

						entity->state()->state_axis.change_direction(angle);
					}
				}

				// clientstate axis: roll

				// project entity->axis().up() into the plane with entity->state()->axis().forward() normal
				n = entity->state()->axis().forward();
				p = entity->axis().up();
				u = p[0]*n[0] + p[1]*n[1] + p[2]*n[2] / (-n[0]*n[0] - n[1]*n[1] - n[2] * n[2]);
				p = entity->axis().up() + u * n;

				side = entity->state()->axis().left().x * p.x + 
				       entity->state()->axis().left().y * p.y +
				       entity->state()->axis().left().z * p.z;

				if (fabs(side) > 0.00005f) {
					cosangle = math::dotproduct(p, entity->state()->axis().up());
					angle = acos(cosangle) * 180.0f / M_PI;
					if (fabs(cosangle) < 0.99995f) {						
						angle = math::sgnf(side) * angle * seconds / 
							(core::game()->serverframetime() - core::game()->clientframetime());

						entity->state()->state_axis.change_roll(angle);
					}
				}

			}
			
 		}

	}
}

float GameInterface::timeoffset() {

	float d = game_serverframetime - game_previousframetime;
	if (d <= 0)
		return 0;

	float t = game_clientframetime - game_previousframetime;
	return t/d;
}

}