/**
 *  Source file for a linked list in C
 *
 * @authors:        Michael Denzel
 * @creation_date:  2016-09-05
 * @contact:        m.denzel@cs.bham.ac.uk
 */

//standard includes

// TODO: Add the includes you need
#include <stdlib.h>
#include <stdio.h>
//own includes
#include "linkedlist.h"


// TODO: Implement those methods!
int get(list * l, unsigned int index){
    if(index > 0)
    {
        return get(l->next, index-1);
    }

    return l->value;
}

int prepend(list * l, int data){
    list* preElement = malloc(sizeof(list));
    init(preElement);

    if(preElement == NULL)
    {
        return -1;
    }

    preElement->value = data;
    preElement->next = l;

    return 0;
}

int append(list * l, int data){
    if(l->next != NULL)
    {
        return append(l->next, data);
    }

    list* postElement = malloc(sizeof(list));
    init(postElement);

    if(postElement == NULL)
    {
        return -1;
    }

    postElement->value = data;
    l->next = postElement;

    return 0;
}

int remove_element(list * l, unsigned int index){
    if(index > 1)
    {
        if(l->next == NULL)
        {
            return -1;
        }

        return remove_element(l->next, index - 1);
    }else if(index == 1)
    {
        if(l->next == NULL)
        {
            return -1;
        }

        list* tail = l->next->next;

        l->next = tail;

        free(l->next);
    }else
    {
        free(l);
    }

    return 0;
}

int insert(list * l, unsigned int index, int data){

    if(index > 1)
    {
        if(l->next == NULL)
        {
            return -1;
        }

        return insert(l->next, index - 1, data);
    }else if(index == 1)
    {
        list* newElement = malloc(sizeof(list));
        init(newElement);
        newElement->value = data;

        if(l->next == NULL)
        {
            l->next = newElement;
        }else
        {
            list* tail = l->next;
            l->next = newElement;
            newElement->next = tail;
        }
    }else
    {
        prepend(l, data);
    }

    return 0;
}

void print_list(list * l){
    printf("%d", l->value);

    if(l->next != NULL)
    {
        printf(", ");
        print_list(l->next);
    }
}

void init(list * l){
    l->next = malloc(sizeof(list*));
    l->value = 0;
}

void destroy(list *l){
    if(l->next != NULL)
    {
        destroy(l->next);
    }

    free(l);
}