import java.util.Scanner;

/**
 *  Week 4 lab solution, includes all computation and input validation, 
 *  but not loops to get good input data.
 * 
 *  Version 1: uses various Scanner methods to get input
 * 
 *  Violates checkstyle cyclomatic complexity because of so many 
 *  decision statements in one method!
 */
public class Courses1 {
    
   /**
    *  Main method, start of execution.
    *  @param args not used
    */
   public static void main(String[] args) {
      Scanner keyboard = new Scanner(System.in);
      int majorCode, // student's major department
          departNum, // class department
          courseNum,  // class number
          indexW, indexS, indexH; // indices of 'W', 'S' and 'H'
   
      boolean elective = true; // not any requirements
         
      String designators;  // department designators
      double course;       // full course identifier
      double credits;      // amount of credits
      
      final int math = 110;
      final int ams = 550;
      final int credmin = 3;
      final int maxnum = 999;
      final float maxcreds = 4.5f;
      final int factor = 5;
      final int thous = 1000;
      final int upper = 300;
   
      boolean valid = true;   // input data is good
        
      // get student's major department
      System.out.println("Enter major department code: "); 
      majorCode = keyboard.nextInt(); // input
   
      // get course data
      System.out.println("Enter course data (dpt.num credits HSEQNW): "); 
        
      course = keyboard.nextDouble(); // course number input ###.### format
      credits = keyboard.nextDouble(); // amount of credits
      designators = keyboard.next(); // academic designators
      designators = designators.toUpperCase();  // for consistency
        
      // department part of course
      departNum = (int) course;
      // course number part of course
      courseNum = (int) (course * thous) % thous;
   
      // input validity checks
      if (departNum < 1 || departNum > maxnum
         || courseNum < 1 || courseNum > maxnum
         || majorCode < 1 || majorCode > maxnum
         || (int) (credits * 2 * factor) % factor != 0 
         || credits < 1 || credits > maxcreds) {
         valid = false;
      }
      // preview: need loop to check area designators validity
      for  (int i = 0; i < designators.length(); i++) {
         if (("HSEQNW").indexOf(designators.charAt(i)) < 0) {
            valid = false;
         }
      }
      if (!valid) {
         System.out.println("invalid input, exitting program!");
      } 
      else {
        
         // search for 'H' in designators
         indexH = designators.indexOf('H');
         // search for 'W' in designators
         indexW = designators.indexOf('W');
         // search for 'S' in desginators
         indexS = designators.indexOf('S'); 


         //copy double course code into string
         String courseStr = course + "";

         //output user's data in parsed form
         final int dotPos = 3;
         System.out.println("Major code: " + majorCode);
         //substring methods are used to access parts of the course code
         System.out.println("Department #: " + courseStr.substring(0,
             dotPos));
         System.out.println("Course #: " + courseStr.substring(dotPos
             + 1));
         System.out.println("Credits: " + credits);
         System.out.println("Areas: " + designators);
        
         // if class department is 110 or 550...
         if (departNum == math | departNum == ams) {
            // the class counts for math requirement
            elective = false; // if any of these apply, elective becomes false
            System.out.println("Course can be counted towards your "
                           + "math requirement."); 
         }
        
         // if there is a W and the class is at least 3 credits
         if (indexW != -1 && credits >= credmin) {
            // the clss counts for writing requirement
            System.out.println("Course can be counted towards your "
                           + "writing requirement."); 
            elective = false; // if any of these apply, elective becomes false
         }
      
         // if there is a H or S designator and the class is at least 3 credits 
         if ((indexH != -1 || indexS != -1) && credits >= credmin) {
            // the class counts for HS
            System.out.println("Course can be counted towards your "
                           + "HS requirement.");   
            elective = false; // if any of these apply, elective becomes false
         }
        
         // if the class is in the same class as the student's major...
         if (majorCode == departNum) {
            elective = false; 
            // and the class number is < 300
            if (courseNum < upper) {
               // the class satisfies a lower level major req.
               System.out.println("Course can be counted towards your "
                              + "lower level major requirement."); 
            } 
            else {
               // the class satisfies an upper level major req
               System.out.println("Course can be counted towards your "
                              + "upper level major requirement."); 
            }
         }
        
      // if elective is still true
         if (elective) {
            // the class counts as an elective
            System.out.println("Course can be counted as "
               + "elective credit only."); 
         }
      }
   }
}