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

/*
 * Print the size and the contents of a list. 
 */
void
List_dump(List_T list)
{
   List_iterator_T p;

   printf("%d\n", List_size(list));
   for (p = List_begin(list); p != List_end(list); p = List_next(p))
   {
      printf("%s\n", List_element(list, p));
   }
}

int
main(int argc, char *argv[])
{
   List_T          list;
   List_iterator_T p;
   int             i;

   list = List_new();

   /*
    * Insert the command line arguments in the list. Each argument is
    * inserted in the END of the list. 
    */
   for (i = 0; i < argc; i++)
   {
      List_insert(list, List_end(list), argv[i]);
   }

   /*
    * Remember where the beginning of the list was before the next
    * insertions. 
    */
   p = List_begin(list);

   /*
    * Insert the command line arguments in the list again. This time
    * each argument is inserted in the BEGINING of the list. 
    */
   for (i = 0; i < argc; i++)
   {
      List_insert(list, List_begin(list), argv[i]);
   }

   /*
    * Insert a separator between the two copies of the arguments. 
    */
   List_insert(list, p, "Separator");
   p = List_previous(p);   /* Remember the position of the separator. */
   List_dump(list);

   /*
    * Erase the separator. 
    */
   printf("After erasing %s\n", List_erase(list, p));
   List_dump(list);

   /*
    * Traverse the first half of the list erasing the elements from the
    * BEGINNING of the list. 
    */
   for (i = 0; i < argc; i++)
   {
      printf("Erasing %s\n", List_erase(list, List_begin(list)));
   }
   List_dump(list);

   /*
    * Traverse the rest of the list erasing the elements from the END
    * of the list. Notice that the element erased is the first one
    * before the one pointed to by List_end(), since List_end() points
    * to the first *unused* node. 
    */
   while (!List_is_empty(list))
   {
      printf("Erasing: %s\n", List_erase(list, List_previous(List_end(list))));
   }
   List_dump(list);

   List_delete(&list);

   return 0;
}