#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#define FPS 10

typedef struct{
    unsigned char *buffer;
    size_t size;
    size_t offset;
}Arena;

Arena arena_create(size_t);
void* arena_alloc(Arena *, size_t);
void arena_reset(Arena *);
void arena_destroy(Arena *);

int main(void){
    srand(time(NULL));
    Arena  arena =  arena_create(100);

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

        int* ptrLeft = arena_alloc(&arena, sizeof(int));

        if(ptrLeft != NULL){
            *ptrLeft = rand()%FPS;
            printf("El datos del frame es: %d\n", *ptrLeft);
        }

        arena_reset(&arena);
    }

    arena_destroy(&arena);

    return 0;
}

Arena arena_create( size_t bytes){
    Arena new_arena = {
        .buffer = NULL,
        .size = bytes,
        .offset = 0
    };

    new_arena.buffer = (unsigned char *)malloc(bytes);

    if(new_arena.buffer == NULL){
        perror("Error asignando memoria");
        exit(1);
    }

    return new_arena;

}
void* arena_alloc(Arena *ref_arena, size_t bytes){

    if(ref_arena->buffer == NULL){
        return NULL;
    }

    if(ref_arena->offset + bytes > ref_arena->size){
        perror("Memoria llena\n");
        return NULL;
    }
    void* ptr_ref = ref_arena->buffer + ref_arena->offset;
    ref_arena->offset += bytes;
    return ptr_ref;
}

void arena_reset(Arena *ref_arena){
    ref_arena->offset = 0;
}

void arena_destroy(Arena *ref_arena){
    if(ref_arena->buffer != NULL){
        free(ref_arena->buffer);
        ref_arena->buffer = NULL;
    }
}