import java.util.Scanner;

/** Java application whose purpose is to partition some arrays using
**  instances of the RedBluePartitioner class, thereby testing that
**  class as well as some classes that implement the RedBlueClassifier
**  interface.
*/
public class RB_PartTester {

   public static void main(String[] args) {

      // Display menu for user.
      System.out.println("Choose among these:");
      System.out.println("  (1) Partition int's by prime vs. nonprime");
      System.out.println("  (2) Partition int's by negative vs. nonnegative");
      System.out.println("  (3) Partition int's by small vs. big");
      System.out.println("  (4) Partition Strings by word vs. nonword");
      System.out.print("\n> ");

      // Get user's response.
      Scanner s = new Scanner(System.in);
      int response = s.nextInt();

      // Establish variable p to refer to a RedBluePartitioner that
      // partitions according to the criteria chosen by the user.
      RedBluePartitioner p = null; 

      if (response == 1) { 
         p = new RedBluePartitioner<Integer>(new PrimeVsComposite());
      }
      else if (response == 2) { 
         p = new RedBluePartitioner<Integer>(new NegVsPosInt());
      }
      else if (response == 3) { 
         System.out.println("Enter smallest big number: ");
         int lowestBig = s.nextInt();
         p = new RedBluePartitioner<Integer>(new SmallVsBigInt(lowestBig));
      }
      else if (response == 4) { 
         p = new RedBluePartitioner<String>(new WordVsNonWord());
      }
      else {
         System.out.println("Invalid response; aborting program");
         System.exit(1); 
      }

      // Make an array x[] filled with either some integers or Strings
      // in accord with the kind of values the user has chosen.
      Object[] x;
      if (response < 4) {
         x = new Integer[] { 3, -4, 77, 0, 95, -2, -5, 64,
                              13, -1, 41, -22, 0, 27, 23 };
      }
      else {
         x = new String[] { "glorp", "25.54", "two_words", "ab%6cd",
                            "spock", "xyz@#$%uv", "the", "dog", "4+7",
                            "hello", "Scranton", "R2D2" };
      }

      // Display the pre-partitioned array.
      System.out.println("\nArray elements:");
      displayArraySegment(x, 0, x.length);
      System.out.println();

      // Partition x[], storing the index at which the BLUE segment begins.
      int rbBoundary = p.partition(x);


      // Display the post-partitioned array.
      System.out.println("\nAfter partitioning,");
      System.out.print("  RED segment: ");
      displayArraySegment(x, 0, rbBoundary);
      System.out.println();

      System.out.print("  BLUE segment: ");
      displayArraySegment(x, rbBoundary, x.length);
      System.out.println();
   }


   /* Displays the elements in the given array segment (z[low..high)).
   */
   private static void displayArraySegment(Object[] z, int low, int high)
   {
      for (int i = low; i != high; i++) 
         { System.out.print(z[i] + " "); }
   }

}