#ifndef __ZECSY_H
#define __ZECSY_H

#define STB_DS_IMPLEMENTATION
#include "stb_ds.h"
#include <stdlib.h>
#include <stddef.h>

#define RESERVED_ENTITY_ID 0
typedef size_t entity_id;

typedef struct
{
    struct{entity_id key; int value;}* entity_map; 
    entity_id entity_id_counter;
    entity_id alive_entities;
} world;

void make_world(world** w);
void destroy_world(world** w);

entity_id make_entity(world* w);
void destroy_entity(world* w, entity_id e);

int world_has_entity(world* w, entity_id e);

#endif // !__ZECSY_H

#define ZECSY_IMPLEMENTATION //TODO: REMOVE
#ifdef ZECSY_IMPLEMENTATION

void make_world(world** w)
{
    if(!w)
        return;

    (*w) = malloc(sizeof(world));

    (**w) = (world)
    {
        .entity_map = NULL,
        .entity_id_counter = RESERVED_ENTITY_ID + 1,
        .alive_entities = 0,
    };
}

void destroy_world(world** w)
{
    if(!w || !(*w))
        return;

    if((*w)->entity_map)
        hmfree((*w)->entity_map);

    free((*w));
    (*w) = NULL;
}

entity_id make_entity(world* w)
{
    entity_id e = RESERVED_ENTITY_ID;
    
    if(w)
    {
        e = w->entity_id_counter++;
        hmput(w->entity_map, e, 1);
        w->alive_entities++;
    }

    return e;
}

void destroy_entity(world* w, entity_id e)
{
    if(w)
        hmdel(w->entity_map, e);
}

int world_has_entity(world* w, entity_id e)
{
    if(w)
    {
        return hmgeti(w->entity_map, e) != -1;
    }

    return 0;
}

#endif // ZECSY_IMPLEMENTATION