// Introduction to Software Testing
// Authors: Paul Ammann & Jeff Offutt
// Chapter 7; page ??
// Can be run from command line
// See TriTyp.num for a numbered version.
// No JUnit tests at this time.

import java.io.*;

public class TriTyp
{
   private static String[] triTypes = { "", // Ignore 0.
      "scalene", "isosceles", "equilateral", "not a valid triangle"};
   private static String instructions = "This is the ancient TriTyp program.\nEnter three integers that represent the lengths of the sides of a triangle.\nThe triangle will be categorized as either scalene, isosceles, equilateral\nor invalid.\n";

public static void main (String[] argv)
{  // Driver program for TriTyp
   int A, B, C;
   int T;

   System.out.println (instructions);
   System.out.println ("Enter side 1: ");
   A = getN();
   System.out.println ("Enter side 2: ");
   B = getN();
   System.out.println ("Enter side 3: ");
   C = getN();
   T = triang (A, B, C);

   System.out.println ("Result is: " + triTypes[T]);
}

// ====================================
// The main triangle classification method
private static int triang (int Side1, int Side2, int Side3)
{
   int triOut;

   // triOut is output from the routine:
   //    triang = 1 if triangle is scalene
   //    triang = 2 if triangle is isosceles
   //    triang = 3 if triangle is equilateral
   //    triang = 4 if not a triangle

   // After a quick confirmation that it's a valid
   // triangle, detect any sides of equal length
   if (Side1 <= 0 || Side2 <= 0 || Side3 <= 0)
   {
      triOut = 4;
      return (triOut);
   }

   triOut = 0;
   if (Side1 == Side2)
      triOut = triOut + 1;
   if (Side1 == Side3)
      triOut = triOut + 2;
   if (Side2 == Side3)
      triOut = triOut + 3;
   if (triOut == 0)
   {  // Confirm it's a valid triangle before declaring
      // it to be scalene

     if (Side1+Side2 <= Side3 || Side2+Side3 <= Side1 ||
        Side1+Side3 <= Side2)
        triOut = 4;
     else
        triOut = 1;
     return (triOut);
   }

   // Confirm it's a valid triangle before declaring
   // it to be isosceles or equilateral

   if (triOut > 3)
      triOut = 3;
   else if (triOut == 1 && Side1+Side2 > Side3)
      triOut = 2;
   else if (triOut == 2 && Side1+Side3 > Side2)
      triOut = 2;
   else if (triOut == 3 && Side2+Side3 > Side1)
      triOut = 2;
   else
      triOut = 4;
   return (triOut);
} // end Triang

// ====================================
// Read (or choose) an integer
private static int getN ()
{
   int inputInt = 1;
   BufferedReader in = new BufferedReader (new InputStreamReader (System.in));
   String inStr;

   try
   {
      inStr    = in.readLine ();
      inputInt = Integer.parseInt(inStr);
   }
   catch (IOException e)
   {
      System.out.println ("Could not read input, choosing 1.");
   }
   catch (NumberFormatException e)
   {
      System.out.println ("Entry must be a number, choosing 1.");
   }

   return (inputInt);
}  // end getN

}  // end TriTyp class