import java.util.Scanner; // import Java utility known as the Scanner variable type for the later use of user input

public class GradeBookV2 {

    public static void main(String[] args) {

                            // ------------------ Declaring variables -------------------- \\

        Scanner keybd = new Scanner(System.in); // This will create a Scanner type class for the user's input

        String course_prefix = "";                          // the name of the course in a prefix format (ABC 1234)


        double score1;
        double score2;                                      // The 3 test scores for each course
        double score3;

        double average = 0;                                 // the Average of the 3 test scores, and therefore, the grade for the course grade in percentage format.
        String letterGrade = "";                            // A,B,C,D,F
        double gradePoint = 0.0;                            // 4.0, 3.0, 2.0, 1.0
        double GPA = 0.0;

        String output = "";



                        // ----------------- Startup prompt of the program --------------- \\

        System.out.println("Welcome to GradeBook!");
        System.out.println("This program will list your course grades in three different formats, along with your semester GPA.");
        System.out.println("Please note: Enter your courses through a prefix format (Ex: CUS 1115) and your grades through an integer format (Ex: 95).");


                       // ---------------------------- Task (Loop) --------------------------- \\


        for (int course = 1; course <= 4; course++)
        {
            {
                System.out.println("\nEnter the course prefix for Course " + course + ":");
                course_prefix = keybd.nextLine();

                System.out.println("Enter the three test scores for the course: ");
                score1 = keybd.nextDouble();
                score2 = keybd.nextDouble();
                score3 = keybd.nextDouble();

                keybd.nextLine();

                average = (score1 + score2 + score3) / 3.0;
                GPA = (GPA + gradePoint) + 0.25;    // <--- *I don't know what's wrong with the program! It keeps giving me a Semester GPA value of 0.25 less than what it's actually supposed to be

            }


    // if Statements:

            if (average >= 90)
            {
                letterGrade = "A";
                gradePoint = 4.0;
            }

            else if (average >= 80)
            {
                letterGrade = "B";
                gradePoint = 3.0;
            }

            else if (average >= 70)
            {
                letterGrade = "C";
                gradePoint = 2.0;
            }

            else if (average >= 60)
            {
                letterGrade = "D";
                gradePoint = 1.0;
            }

            else if (average < 60)
            {
                letterGrade = "F";
                gradePoint = 0.0;
            }


                // ---------------------------------------------------- Result Output -------------------------------------------------------- \\

            String lines = ("\n%-8s%17.2f%15s%20s");
            output += String.format(lines, course_prefix, average, letterGrade, gradePoint);    // OR: output = output + String.format(format, course_prefix......)

        }       // <---- End of for-loop


        // The Line 0 represents the titles for each section displayed:
            String line_0 = ("\n%-6s%20s%20s%20s");
            System.out.printf(line_0 , "Course" , "Average", "Letter Grade", "Grade Points");

        // The output variable displays the information for all 4 courses below:
            System.out.println(output);

            GPA = GPA / 4.0;
            System.out.println("\nGPA: " + GPA);
    }

}