StudentMenu

import java.util.ArrayList;
import java.util.Scanner;

/**
* This class allows a user to manage a database of students.
*/
public class StudentMenu {
    private StudentManager studentManager;
    private Scanner scanner;
    

    /**
    * This constructor creates a StudentMenu object.
    */
    public StudentMenu() {
        studentManager = new StudentManager();
        scanner = new Scanner(System.in);
    }

    /**
    * This method displays the user menu.
    */
    public void displayMenu() {
        System.out.println("1. Add Student");
        System.out.println("2. Remove Student");
        System.out.println("3. Modify Student");
        System.out.println("4. Display Students");
        System.out.println("5. Display Students final grades");
        System.out.println("6. Exit");
    }

    /**
    * This method gets the user's choice.
    * 
    * @return The user's choice.
    */
    public int getChoice() {
        return scanner.nextInt();
    }

    /**
     * This method allows the user to add a student to the database.
     */
    public void addStudent() {
        System.out.println("Enter the student's first name:");
        String firstName = scanner.next();
        System.out.println("Enter the student's last name:");
        String lastName = scanner.next();
        System.out.println("Enter the student's ID:");
        String id = scanner.next();
        scanner.nextLine(); 
        
        // Prompt the user to enter the quiz grades
        System.out.println("Enter the student's quiz grades (separated by spaces):");
        ArrayList<Double> quizGrades = new ArrayList<>();
        String[] quizGradesStr = scanner.nextLine().trim().split("\\s+");
        for (String grade : quizGradesStr) {
            if (!grade.isEmpty()) {
                quizGrades.add(Double.parseDouble(grade));
            }  
        }
        
        // Prompt the user to enter the lab grades
        System.out.println("Enter the student's lab grades (separated by spaces):");
        ArrayList<Double> labGrades = new ArrayList<>();
        String[] labGradesStr = scanner.nextLine().trim().split("\\s+");
        for (String grade : labGradesStr) {
            if (!grade.isEmpty()) {
                labGrades.add(Double.parseDouble(grade));
            }         
        }
        
        // Prompt the user to enter the project grade
        System.out.println("Enter the student's project grade:");
        double projectGrade = scanner.nextDouble();
        
        // Prompt the user to enter the midterm grade
        System.out.println("Enter the student's midterm grade:");
        double midtermGrade = scanner.nextDouble();
        
        // Prompt the user to enter the final grade
        System.out.println("Enter the student's final grade:");
        double finalGrade = scanner.nextDouble();
        
        // Prompt the user to enter the attendance grade
        System.out.println("Enter the student's attendance grade:");
        double attendanceGrade = scanner.nextDouble();
        
        // Create the student and add them to the database
        StudentGrades grades = new StudentGrades(quizGrades, labGrades, projectGrade, midtermGrade, finalGrade, attendanceGrade);
        Student student = new Student(firstName, lastName, id, grades);
        studentManager.addStudent(student);
        System.out.println("Student added.");
    }
    

    

    /**
    * This method removes a student from the database.
    */
    public void removeStudent() {
        System.out.println("Enter the student's ID:");
        String id = scanner.next();
        Student student = studentManager.getStudent(id);
        studentManager.removeStudent(student);
        System.out.println("Student removed.");
    }
    

    /**
    * This method modifies a student's information.
    */
    public void modifyStudent() {
        System.out.println("Enter the student's ID:");
        String id = scanner.next();
        Student student = studentManager.getStudent(id);
        System.out.println("Enter the student's new first name:");
        String firstName = scanner.next();
        System.out.println("Enter the student's new last name:");
        String lastName = scanner.next();
        studentManager.modifyStudent(student, firstName, lastName, id);
    }

    /**
    * This method displays all students in the database.
    */
    public void displayStudents() {
        ArrayList<Student> students = studentManager.getStudents();
        for (Student student : students) {
            System.out.println(student);
        }
    }

    

    /**
     * This method searches for a student in the database.
     * and displays their final grade.
     */
    public void searchStudent() {
        scanner.nextLine(); 
        System.out.println("Enter the student's first name or ID:");
        String searchInput = scanner.nextLine();
        Student student = studentManager.getStudent(searchInput);
        System.out.println(student + "\nStudent: " + student.getFirstName() + "\n has a total grade average of " + student.getGrades().getTotalGradeAverage() + ",\n a letter grade of " + student.getGrades().getLetterGrade() + ",\n and a GPA of " + student.getGrades().getGPA() + ".");
    }
    


    /**
    * This method runs the program.
    */
    public void run() {
        int choice = 0;
        while (choice != 6) {
            displayMenu();
            choice = getChoice();
            switch (choice) {
                case 1:
                    addStudent();
                    break;
                case 2:
                    removeStudent();
                    break;
                case 3:
                    modifyStudent();
                    break;
                case 4:
                    displayStudents();
                    break;
                case 5:
                    searchStudent();
                    break;
                case 6:
                    System.out.println("Goodbye!");
                    break;
                default:
                    System.out.println("Invalid choice.");
            }
        }

    }
}