package username.lists;

import java.util.Vector;

/**
 * Simple Lists implemented with Vectors (as the name implies).
 *
 * @author Samuel A. Rebelsky
 * @author CSC152 2006S
 */
public class VectorBasedSimpleList<V>
  implements SimpleList<V>
{

// +------------------+-------------------------------------
// | Design Decisions |
// +------------------+

/*

(1) We store the values in the list in a vector.

(2) Positions are therefore integer indices into the Vector.

*/

// +--------+-----------------------------------------------
// | Fields |
// +--------+

  /**
   * The vector in which all the values are stored.
   */
  Vector<V> contents;


// +--------------+-----------------------------------------
// | Constructors |
// +--------------+

  public VectorBasedSimpleList()
  {
    this.contents = new Vector<V>();
  } // VectorBasedSimpleList

// +----------------+---------------------------------------
// | Public Methods |
// +----------------+

  /**
   * Get the position of the front of this list.
   *
   * @return pos
   *   A position that represents the front of the list.
   * @pre
   * @post
   */
  public Position front()
  {
    return new VectorPosition(0);
  } // front()

  /**
   * Get the position of the end of the list.
   *
   * @return pos
   *   A position that represents the end of the list.
   * @pre
   * @post
   */
  public Position rear()
  {
    return new VectorPosition(this.contents.size()-1);
  } // rear()


  /**
   * Get the position that follows pos.
   *
   * @return succ
   *   The position of the successor of the value at pos.
   * @pre
   * @post
   */
  public Position successor(Position pos)
  {
    return null; // STUB
  } // successor(Position)

  /**
   * Get the position that precedes pos.
   *
   * @return pred
   *   The position of the predecessor of the value at pos.
   * @pre
   * @post
   */
  public Position predecessor(Position pos)
  {
    return null; // STUB
  } // predecessor(Position)

  /**
   * Get the value at a particular position.
   *
   * @return val
   *   The value at that position in the list.
   * @pre
   * @post
   */
  public V get(Position pos)
  {
    return this.contents.get(((VectorPosition) pos).pos);
  } // get(Position)

  /**
   * Determine if a position represents the first position in
   * the list.
   *
   * @return 
   *   True, if pos is the first position.  False, otherwise.
   * @pre
   * @post
   */
  public boolean isFirst(Position pos)
  {
    return true; // STUB
  } // isFirst(Position)

  /**
   * Determine if a position represents the last position in
   * the list.
   *
   * @return 
   *   True, if pos is the last position.  False, otherwise.
   * @pre
   * @post
   */
  public boolean isLast(Position pos)
  {
    return true; // STUB
  } // isLast()

  /**
   * Determine if the list is empty.
   *
   * @return
   *   true, if the list is empty; false, otherwise.
   */
  public boolean isEmpty()
  {
    return this.contents.size() == 0;
  } // isEmpty()

  /**
   * Add a value to the list.
   *
   * @pre
   * @post
   */
  public void add(V value)
  {
    this.contents.add(value);
  } // add(V)

  /**
   * Delete the value at a particular position.
   *
   * @pre
   * @post
   */
  public void delete(Position pos)
  {
    // Note: Position should be a VectorPosition, which has one
    // field, an int called pos
    this.contents.remove(((VectorPosition) pos).pos);
  } // delete(Position)

  public void removeAll()
  {
    // STUB
  } // removeAll()

// +-----------------+--------------------------------------
// | Private Methods |
// +-----------------+

} // interface SimpleList<V>