#ifndef TC_PHYSICS_SIMULATION_H
#define TC_PHYSICS_SIMULATION_H

#include <stdint.h>

#include <physics/primitives.h>
#include <utility/utility.h>
#include <entity.h>

typedef struct  tc_physics_entity               tc_physics_entity_s;
typedef struct  tc_entity_physics_attributes    tc_entity_physics_attributes_s;
typedef struct  tc_physics_simulation           tc_physics_simulation_s;

struct tc_entity_physics_attributes
{
    bool_t          has_gravity;
    
    bool_t          raw_movement;
    bool_t          raw_rotation;
    
    tc_vec3f_s      acceleration;
    tc_vec3f_s      spin;
};

typedef enum
{
    TC_PHYSICS_ENTITY,
    TC_PHYSICS_ENTITY_GROUP
    
} tc_physics_entity_type_e;

struct tc_physics_entity
{
    tc_physics_simulation_s    *simulation;
    tc_physics_entity_s        *super;
    
    // relative_position: The position of this physics entity relative to its super-entity
    tc_vec3f_s                  relative_position;
        
    tc_physics_entity_type_e    type;
    union specific
    {
        struct entity
        {
            char                       *name;
            tc_physics_mesh_s           mesh;
            
        } entity;
        
        struct subentity_group
        {
            u32_t                       entities_capacity;
            u32_t                       num_entities;
            tc_physics_entity_s       **entities;
            
        } group;
        
    } value;
};

struct tc_physics_simulation
{
    tc_physics_entity_s        *root;
    
};

tc_physics_simulation_s *   tc_new_physics_simulation   ();
void                        tc_add_physics_object       (tc_physics_simulation_s *simulation, tc_physics_entity_s *object);
void                        tc_add_physics_object_to    (tc_physics_entity_s *container, tc_physics_entity_s *object);

tc_physics_entity_s *       tc_new_physics_entity       (tc_physics_simulation_s *simulation);
tc_physics_entity_s *       tc_new_physics_group        (tc_physics_simulation_s *simulation);

void                        tc_remove_physics_entity    (tc_physics_entity_s *entity);

void                        tc_tick_physics             (tc_physics_simulation_s *simulation, f32_t delta);

tc_primitive_s *            tc_cast_line                (tc_physics_simulation_s *simulation, tc_line_s line);

#endif