/** This ShoppingList class represents an array of Items
 */
import java.io.*;
import java.util.*;
import java.text.*;

public class ShoppingList
{
  private Item [] list;

  /** For our (default) constructor, we ask the user to enter the number of
   * items, and the particulars for each of the items here.
   */
  public ShoppingList() throws IOException
  {
    BufferedReader kbd = new BufferedReader(new InputStreamReader(System.in));

    System.out.print("how many items are you buying?  ");
    int n = Integer.parseInt(kbd.readLine());

    // allocate space for the shopping list
    list = new Item[n];

    // for each item we want to buy, create an Item object
    // and put it in the array
    for (int i = 0; i < n; ++i)
    {
      System.out.print("enter name and price of item # " + (i+1) + ":  ");
      String input = kbd.readLine();
      StringTokenizer tok = new StringTokenizer(input, ", ");

      String itemName = tok.nextToken();
      double itemPrice = Double.parseDouble(tok.nextToken());
      Item thing = new Item(itemName, itemPrice);
      list[i] = thing;
    }
  }

  /** getTotal() adds up the price of each item on my shopping list.
  * Notice the way we find the price of each item -- the Item class has
  * an instance method called getPrice, because technically the price is
  * an attribute of the item and therefore "private" information.  We can
  * see the price thanks to getPrice(), but can't change it.
  * Also note that list.length is the number of items in the array.
  */
  public double getTotal()
  {
    double sum = 0.0;
    for (int i = 0; i < list.length; ++i)
      sum += list[i].getPrice();
    return sum;
  }

  /** sortList() will sort the items in our list in descending order of
   * price.  This is not the most efficient way of sorting, but it is
   * one of the more straightforward and easy to remember.  The basic
   * idea is that we want to swap any elements on the list that appear out
   * of order.
   */
  public void sortList()
  {
    for (int i = 0; i < list.length; ++i)
      for (int j = i+1; j < list.length; ++j)
        if (list[i].getPrice() < list[j].getPrice())
        {
	  Item tempItem = new Item(list[i].getName(), list[i].getPrice());
          list[i] = list[j];
          list[j] = tempItem;
        }
  }

  /** printList() will print the shopping list in an attractive format.
   *  We could have written this function as toString(), so that we create
   *  and build the string representing the entire shopping list, rather than
   *  printing the whole thing out here.
   */
  public void printList()
  {
    for (int i = 0; i < list.length; ++i)
    {
      System.out.println(list[i]);
    }

    // at the end, print a total
    NumberFormat f = NumberFormat.getNumberInstance();
    f.setMaximumIntegerDigits(4);
    f.setMinimumIntegerDigits(1);
    f.setMaximumFractionDigits(2);
    f.setMinimumFractionDigits(2);
    String expr = f.format(getTotal());

    while (expr.length() < 8)
      expr = " " + expr;
    System.out.println("----------------------------------------");
    System.out.println(" $ " + expr + "  TOTAL");
  }
}