#include <stdint.h>
#include <stddef.h>
#include <stdbool.h>

#include "vector.h"
#include "alloc.h"

zv_vector_t * zv_vector_create() {
    zv_vector_t *result = (zv_vector_t *) zv_alloc(sizeof(zv_vector_t));
    
    if (result == NULL) {
        return NULL;
    }

    result->lenght = 0;
    result->first = NULL;
    result->last = NULL;

    return result;    
}

static inline zv_vector_container_t * __zv_vector_count_right(
    zv_vector_t *self,
    size_t count
) {
    zv_vector_container_t *current = self->last;
    count = self->lenght - count;
    
    while (count-- > 0) {
        current = current->previous;

        if (current == NULL) {
            return NULL;
        }
    }

    return current;
}

static inline zv_vector_container_t * __zv_vector_count_lefr(
    zv_vector_t *self,
    size_t count
) {
    zv_vector_container_t *current = self->first;

    while (count-- > 0) {
        current = current->next;

        if (current == NULL) {
            return NULL;
        }
    }

    return current;
}

static zv_vector_container_t * __zv_vector_get_container(
    zv_vector_t *self, 
    size_t count
) {
    if (self->lenght <= count) {
        return NULL;
    }

    if (self->lenght / 2 > count) {
        return __zv_vector_count_right(self, count);
    } 

    return __zv_vector_count_left(self, count);
}

zv_universal_t zv_vector_get(zv_vector_t *self, size_t count) {
    zv_vector_container_t *current = __zv_vector_get_container(self, count);
    
    if (current == NULL) {
        return NULL;
    }

    return current->content;
}

size_t zv_vector_push(zv_vector_t *, zv_universal_t);
size_t zv_vector_count(zv_vector_t *);
zv_universal_t zv_vector_pop(zv_vector_t *, size_t);
bool zv_vector_insert(zv_vector_t *, zv_universal_t, size_t);
void zv_vector_remove(zv_vector_t *);
zv_universal_t * zv_vector_to_array(zv_vector_t *);