// Zorah Fung, CSE 142
// This program takes in a file of section attendance scores and reports grades
// for each student in each section.
// In the data file:
//   -'y' represents 5 points (student went to section and turned in HW)
//   -'n' represents 0 points (student was absent)
// Each student can get up to 30 section points. 

import java.util.*;
import java.io.*;

public class Section {
   public static final int SECTION_MAX = 30;
   
   public static void main(String[] args) throws FileNotFoundException {
      Scanner fileScan = new Scanner(new File("sections.txt"));
      PrintStream output = System.out;// new PrintStream(new File("sections_out.txt"));
      
      int section = 1;
      while (fileScan.hasNextLine()) {
         String line = fileScan.nextLine();
         // Two options: we can either 
         // 1. Initialize student points in main and pass it to calculateStudentPoints and have
         //    the method modify it through reference semantics (aka, an array would not need
         //    to be returned)
         // 2. have calculateStudentPoints return a new result array to main.
         // We chose option 2 in this case.
         int[] studentPoints = calculateStudentPoints(line);
         double[] studentGrades = calculateStudentGrades(studentPoints);
         printResults(output, section, studentPoints, studentGrades);
         // printResults(System.out, section, studentPoints, studentGrades); // print to console
         section++;
      }
   }
   
   // Reads in a line representing attendance for a particular section and returns
   // an array representing the total number of points received by each student in the class
   // Note: We've pulled out this code into a method, because it performs a single
   // data transformation, converting a String of attendance for students to an array of counts
   public static int[] calculateStudentPoints(String line) {
      int[] studentPoints = new int[5];
      for (int i = 0; i < line.length(); i++) {
         char attendance = line.charAt(i);
         int studentIndex = i % 5;
         if (attendance == 'y'){ // did the homework
            studentPoints[studentIndex] += 5;
            studentPoints[studentIndex] = Math.min(SECTION_MAX, studentPoints[studentIndex]);
         } /* else {
            studentPoints[studentIndex] += 0;
         }*/
      }
      return studentPoints;
   }
   
   // Takes an array of points for students and returns a new array of grades out of 100 from
   // the given scores. 
   public static double[] calculateStudentGrades(int[] studentPoints) {
      double[] studentGrades = new double[5];
      for (int i = 0; i < studentGrades.length; i++) {
         studentGrades[i] = (double) studentPoints[i] / SECTION_MAX * 100;
      }
      return studentGrades;
   }
   
   // Prints the points and grades of the students in the given section, printing to the
   // given PrintStream
   public static void printResults(PrintStream output, int section, int[] studentPoints,
                                   double[] studentGrades) {
      output.println("Section " + section);
      output.println("Student points: " + Arrays.toString(studentPoints));
      output.println("Student grades: " + Arrays.toString(studentGrades));
      output.println();
   }
}