#format cplusplus

// LinkedList example
#include <stdlib.h>
#include <string.h>

#include "LinkedList.h"

void list_init(List *list, void (*destroy)(void *data)) {
    list->size = 0;
    list->destroy = destroy;
    list->head = NULL;
    list->tail = NULL;
    return;
}

void list_destroy(List *list) {
    void *data;
    while(list_size(list) > 0) {
        if(list_rem_next(list, NULL, (void **)&data) == 0 && 
                list->destroy != NULL) {
            list->destroy(data);
        }
    }
    memset(list, 0, sizeof(List));
    return;
}

int list_ins_next(List *list, ListElmt *element, const void *data) {
    ListElmt *new_element;
    if((new_element=(ListElmt *)malloc(sizeof(ListElmt))) == NULL)
        return -1;
    new_element->data = (void *)data;
    if(element == NULL) {
        // insert in head of list
        if(list_size(list) == 0)
            list->tail = new_element;
        new_element->next = list->head;
        list->head = new_element;
    } else {
        // insert in not head
        if(element->next == NULL)
            list->tail = new_element;
        new_element->next = element->next;
        element->next = new_element;
    }
    list->size++;
    return 0;
}

int list_rem_next(List *list, ListElmt *element, void **data) {
    ListElmt *old_element;
    if(list_size(list) == 0) 
        return -1;
    if(element == NULL) {
        *data = list->head->data;
        old_element = list->head;
        list->head =list->head->next;
        if(list_size(list) == 1)
            list->tail = NULL;
    } else {
        if(element->next == NULL)
            return -1;
        *data = element->next->data;
        old_element = element->next;
        element->next = element->next->next;
        if(element->next == NULL)
            list->tail = element;
    }
    free(old_element);
    list->size--;
    return 0;
}