package HW5;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;

/**
   A table for lookups and reverse lookups
*/
public class LookupTable
{
   private ArrayList<Item> byName;
   private ArrayList<Item> byNumber;

   /**
      Constructs a LookupTable object.
   */
   public LookupTable()
   {
      byName = new ArrayList<Item>();
      byNumber = new ArrayList<Item>();
   }

   /**
      Reads name and number pairs from the Scanner
      and adds them to the byName and byNumber array lists.
      @param in the scanner for reading the input
   */
   public void read(Scanner in)
   {
      while (in.hasNextLine())
      {
         // Read a line containing the name
         String name = new String(in.nextLine());

	 // Read a line containing the number
         String number = new String(in.nextLine());

	 // Store the name and number in the byName array list
         Item Name = new Item(name, number);
         byName.add(Name);

	 // Store the number and name in the byNumber array list
         Item Number = new Item(number, name);
         byNumber.add(Number);
      }

      // Sort the byName Items so we can binary search
      Collections.sort(byName);
      // Sort the byNumber Items so we can binary search
      Collections.sort(byNumber);
   }

   /**
      Looks up an item in the table.
      @param k the key to find
      @return the value with the given key, or null if no
      such item was found.
   */
   public String lookup(String k)
   {
      // Use the Collections.binarySearch() method to find the
      // position of the matching name in the byName array list.
      // Return null if position is less than 0 (not found).
      // Otherwise, return the number for the found name.

   }

   /**
      Looks up an item in the table.
      @param v the value to find
      @return the key with the given value, or null if no
      such item was found.
   */
   public String reverseLookup(String v)
   {
      // Use the Collections.binarySearch() method to find the
      // position of the matching number in the byNumber array list.
      // Return null if position is less than 0 (not found).
      // Otherwise, return the name for the found number.

   }
}