/**
 * linked-queue.c
 *   An implementation of stacks using linked lists. 
 */

// +---------+--------------------------------------------------------
// | Headers |
// +---------+

#include "collection.h"
#include <stdlib.h> 	// For malloc
#include <string.h>	// For strdup


// +-------+----------------------------------------------------------
// | Types |
// +-------+

struct node {
  char *data;
  struct node *next;
};

struct collection {
  struct node *head;
  struct node *tail;
  int size;
};


// +-----------+------------------------------------------------------
// | Functions |
// +-----------+

struct collection *
new_collection (int recommended_capacity)
{
  struct collection *result;
  result = malloc (sizeof (struct collection));
  if (result == NULL)
    return NULL;
  result->head = NULL;
  result->tail = NULL;
  result->size = 0;
  return result;
} // new_collection

struct collection *
collection_copy (struct collection *stuff)
{
  struct collection *result = malloc (sizeof (struct collection));
  if (result == NULL)
    return NULL;
  struct node *temp = stuff->head;
  while (temp != NULL)
    {
      collection_put (result, temp->data);
      temp = temp->next;
    }
  return result;
} // collection_copy

void 
collection_free (struct collection *stuff)
{
} // collection_free

int
collection_put (struct collection *stuff, char *str)
{
  // Add to the end of the list
  // Create a new node
  struct node *newbie = malloc (sizeof (struct node));
  newbie->data = strdup (str);
  newbie->next = NULL;
  if (stuff->tail == NULL)
    {
      stuff->head = newbie;
      stuff->tail = newbie;
    }
  else 
    {
      stuff->tail->next = newbie;
      stuff->tail = newbie;
    }
  ++(stuff->size);
  return 1;
} // collection_put

char *
collection_get (struct collection *stuff)
{
  if (stuff->head == NULL)
    return NULL;
  else
    {
      // Get the data from stuff->head
      char *str = stuff->head->data;
      // Save a pointer to the stuff->head
      struct node *dom = stuff->head;
      // Change stuff->head to stuff->head->next
      stuff->head = stuff->head->next;
      // Decrement Size
      --stuff->size;
      // Get rid of the node
      free (dom);
      // Special case
      if (stuff->head == NULL)
        stuff->tail = NULL;
      // And we're done
      return str;
    } // else
} // collection_get

char *
collection_peek (struct collection *stuff)
{
  if (stuff->head == NULL)
    return NULL;
  else
    return stuff->head->data;
} // collection_peek

int
collection_size (struct collection *stuff)
{
  return stuff->size;
} // collection_size

int 
collection_is_empty (struct collection *stuff)
{
  return stuff->head == NULL;
} // collection_is_empty

int 
collection_is_full (struct collection *stuff)
{
  return 0;
} // collection_is_full