#include "chained_functions.h"
#include <stdio.h>

//for information purposes: mom== momentan ((;

messdaten*
insertFirst (messdaten* firstelem, messdaten* newelement)
{
  newelement->next = firstelem;
  return newelement;
}

messdaten*
insertLast (messdaten* firstelem, messdaten* newelement)
{
  messdaten * mom = firstelem;
  while (mom->next != NULL)
    {
      mom = mom->next;
    }
  mom->next = newelement;
  newelement->next = NULL;
  return firstelem;
}

messdaten*
insertPos (messdaten* firstelem, messdaten* newelement, int pos)
{
  pos--;
  messdaten * mom = firstelem;
  int n = 0;
  while (mom->next != NULL)
    {
      if (n == pos)
	{
	  newelement->next = mom->next;
	  mom->next = newelement;
	  return firstelem;
	}
      n++;
      mom = mom->next;

    }
  fprintf (stderr, "failed to allocate list element!!");
  return firstelem;
}

messdaten*
deleteFirst (messdaten* firstelem)
{
  messdaten * temp = firstelem;

  temp = firstelem->next;
  free (firstelem);
  return temp;
}

messdaten*
deleteLast (messdaten* firstelem)
{
  messdaten * mom = firstelem;
  messdaten * temp = NULL;
  while (mom->next != NULL)
    {
      temp = mom;
      mom = mom->next;
    }
  free (temp->next);
  temp->next = NULL;
  return firstelem;
}

messdaten*
deletePos (messdaten* firstelem, int pos)
{
  pos--;
  messdaten * mom = firstelem;
  messdaten * temp = NULL;
  int n = 0;
  while (mom->next != NULL)
    {
      if (n == pos)
	{
	  temp = mom->next;
	  mom->next = mom->next->next;
	  free (temp);
	  return firstelem;
	}
      n++;
      mom = mom->next;

    }
  printf ("failed to allocate list element!!");
  return firstelem;
}

messdaten*
deleteAll (messdaten* firstelem)
{
  messdaten * temp;
  while (firstelem != NULL)
    {
      temp = firstelem;
      firstelem = firstelem->next;
      free (temp);
    }
  return firstelem;
}