/*************************************************************************/
/*  world.cpp                                                            */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                    http://www.godotengine.org                         */
/*************************************************************************/
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
/*                                                                       */
/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
/*************************************************************************/
#include "world.h"
#include "scene/3d/camera.h"
#include "scene/3d/visibility_notifier.h"
#include "scene/3d/spatial_indexer.h"
#include "scene/scene_string_names.h"
#include "octree.h"
#include "camera_matrix.h"

struct SpatialIndexer {


	Octree<VisibilityNotifier> octree;

	struct NotifierData {

		Rect3 aabb;
		OctreeElementID id;

	};

	Map<VisibilityNotifier*,NotifierData> notifiers;
	struct CameraData {

		Map<VisibilityNotifier*,uint64_t> notifiers;
	};

	Map<Camera*,CameraData> cameras;

	enum {
		VISIBILITY_CULL_MAX=32768
	};

	Vector<VisibilityNotifier*> cull;

	bool changed;
	uint64_t pass;
	uint64_t last_frame;

	void _notifier_add(VisibilityNotifier* p_notifier,const Rect3& p_rect) {

		ERR_FAIL_COND(notifiers.has(p_notifier));
		notifiers[p_notifier].aabb=p_rect;
		notifiers[p_notifier].id = octree.create(p_notifier,p_rect);
		changed=true;

	}

	void _notifier_update(VisibilityNotifier* p_notifier,const Rect3& p_rect) {

		Map<VisibilityNotifier*,NotifierData>::Element *E=notifiers.find(p_notifier);
		ERR_FAIL_COND(!E);
		if (E->get().aabb==p_rect)
			return;

		E->get().aabb=p_rect;
		octree.move(E->get().id,E->get().aabb);
		changed=true;
	}

	void _notifier_remove(VisibilityNotifier* p_notifier) {

		Map<VisibilityNotifier*,NotifierData>::Element *E=notifiers.find(p_notifier);
		ERR_FAIL_COND(!E);

		octree.erase(E->get().id);
		notifiers.erase(p_notifier);

		List<Camera*> removed;
		for (Map<Camera*,CameraData>::Element*F=cameras.front();F;F=F->next()) {

			Map<VisibilityNotifier*,uint64_t>::Element*G=F->get().notifiers.find(p_notifier);

			if (G) {
				F->get().notifiers.erase(G);
				removed.push_back(F->key());
			}
		}

		while(!removed.empty()) {

			p_notifier->_exit_camera(removed.front()->get());
			removed.pop_front();
		}


		changed=true;
	}

	void _add_camera(Camera* p_camera) {

		ERR_FAIL_COND(cameras.has(p_camera));
		CameraData vd;
		cameras[p_camera]=vd;
		changed=true;

	}

	void _update_camera(Camera* p_camera) {

		Map<Camera*,CameraData>::Element *E= cameras.find(p_camera);
		ERR_FAIL_COND(!E);
		changed=true;
	}

	void _remove_camera(Camera* p_camera) {
		ERR_FAIL_COND(!cameras.has(p_camera));
		List<VisibilityNotifier*> removed;
		for(Map<VisibilityNotifier*,uint64_t>::Element *E=cameras[p_camera].notifiers.front();E;E=E->next()) {

			removed.push_back(E->key());
		}

		while(!removed.empty()) {
			removed.front()->get()->_exit_camera(p_camera);
			removed.pop_front();
		}

		cameras.erase(p_camera);

	}

	void _update(uint64_t p_frame) {

		if (p_frame==last_frame)
			return;
		last_frame=p_frame;

		if (!changed)
			return;



		for (Map<Camera*,CameraData>::Element *E=cameras.front();E;E=E->next()) {

			pass++;

			Camera *c=E->key();

			Vector<Plane> planes = c->get_frustum();

			int culled = octree.cull_convex(planes,cull.ptr(),cull.size());


			VisibilityNotifier**ptr=cull.ptr();

			List<VisibilityNotifier*> added;
			List<VisibilityNotifier*> removed;

			for(int i=0;i<culled;i++) {

				//notifiers in frustum

				Map<VisibilityNotifier*,uint64_t>::Element *H=E->get().notifiers.find(ptr[i]);
				if (!H) {

					E->get().notifiers.insert(ptr[i],pass);
					added.push_back(ptr[i]);
				} else {
					H->get()=pass;
				}


			}

			for (Map<VisibilityNotifier*,uint64_t>::Element *F=E->get().notifiers.front();F;F=F->next()) {

				if (F->get()!=pass)
					removed.push_back(F->key());
			}

			while(!added.empty()) {
				added.front()->get()->_enter_camera(E->key());
				added.pop_front();
			}

			while(!removed.empty()) {
				E->get().notifiers.erase(removed.front()->get());
				removed.front()->get()->_exit_camera(E->key());
				removed.pop_front();
			}
		}
		changed=false;
	}


	SpatialIndexer() {

		pass=0;
		last_frame=0;
		changed=false;
		cull.resize(VISIBILITY_CULL_MAX);
	}

};



void World::_register_camera(Camera* p_camera) {

#ifndef _3D_DISABLED
	indexer->_add_camera(p_camera);
#endif
}

void World::_update_camera(Camera* p_camera){

#ifndef _3D_DISABLED
	indexer->_update_camera(p_camera);
#endif
}
void World::_remove_camera(Camera* p_camera){

#ifndef _3D_DISABLED
	indexer->_remove_camera(p_camera);
#endif
}




void World::_register_notifier(VisibilityNotifier* p_notifier,const Rect3& p_rect){

#ifndef _3D_DISABLED
	indexer->_notifier_add(p_notifier,p_rect);
#endif
}

void World::_update_notifier(VisibilityNotifier* p_notifier,const Rect3& p_rect){

#ifndef _3D_DISABLED
	indexer->_notifier_update(p_notifier,p_rect);
#endif
}

void World::_remove_notifier(VisibilityNotifier* p_notifier){

#ifndef _3D_DISABLED
	indexer->_notifier_remove(p_notifier);
#endif
}


void World::_update(uint64_t p_frame) {

#ifndef _3D_DISABLED
	indexer->_update(p_frame);
#endif
}





RID World::get_space() const {

	return space;
}
RID World::get_scenario() const{

	return scenario;
}

void World::set_environment(const Ref<Environment>& p_environment) {

	environment=p_environment;
	if (environment.is_valid())
		VS::get_singleton()->scenario_set_environment(scenario,environment->get_rid());
	else
		VS::get_singleton()->scenario_set_environment(scenario,RID());
}

Ref<Environment> World::get_environment() const {

	return environment;
}


PhysicsDirectSpaceState *World::get_direct_space_state() {

	return PhysicsServer::get_singleton()->space_get_direct_state(space);
}

void World::_bind_methods() {

	ClassDB::bind_method(_MD("get_space"),&World::get_space);
	ClassDB::bind_method(_MD("get_scenario"),&World::get_scenario);
	ClassDB::bind_method(_MD("set_environment","env:Environment"),&World::set_environment);
	ClassDB::bind_method(_MD("get_environment:Environment"),&World::get_environment);
	ClassDB::bind_method(_MD("get_direct_space_state:PhysicsDirectSpaceState"),&World::get_direct_space_state);
	ADD_PROPERTY(PropertyInfo(Variant::OBJECT,"environment",PROPERTY_HINT_RESOURCE_TYPE,"Environment"),"set_environment","get_environment");

}


World::World() {

	space = PhysicsServer::get_singleton()->space_create();
	scenario = VisualServer::get_singleton()->scenario_create();

	PhysicsServer::get_singleton()->space_set_active(space,true);
	PhysicsServer::get_singleton()->area_set_param(space,PhysicsServer::AREA_PARAM_GRAVITY,GLOBAL_DEF("physics/3d/default_gravity",9.8));
	PhysicsServer::get_singleton()->area_set_param(space,PhysicsServer::AREA_PARAM_GRAVITY_VECTOR,GLOBAL_DEF("physics/3d/default_gravity_vector",Vector3(0,-1,0)));
	PhysicsServer::get_singleton()->area_set_param(space,PhysicsServer::AREA_PARAM_LINEAR_DAMP,GLOBAL_DEF("physics/3d/default_linear_damp",0.1));
	PhysicsServer::get_singleton()->area_set_param(space,PhysicsServer::AREA_PARAM_ANGULAR_DAMP,GLOBAL_DEF("physics/3d/default_angular_damp",0.1));

#ifdef _3D_DISABLED
	indexer = NULL;
#else
	indexer =  memnew( SpatialIndexer );
#endif
}

World::~World() {

	PhysicsServer::get_singleton()->free(space);
	VisualServer::get_singleton()->free(scenario);

#ifndef _3D_DISABLED
	memdelete( indexer );
#endif


}