package second_term.sixth_chapter;

import java.io.Serializable;

public class Course implements Serializable ,Comparable<Course>{
    private String prefix;
    private int number;
    private String title;
    private String grade;

    public Course(String prefix, int number, String title, String grade)
    {
        this.prefix = prefix;
        this.number = number;
        this.title = title;
        if (grade == null)
            this.grade = "";
        else
            this.grade = grade;
    }

    public Course(String prefix, int number, String title)
    {
        this(prefix, number, title, "");
    }


    public String getPrefix()
    {
        return prefix;
    }


    public int getNumber()
    {
        return number;
    }


    public String getTitle()
    {
        return title;
    }


    public String getGrade()
    {
        return grade;
    }


    public void setGrade(String grade)
    {
        this.grade = grade;
    }


    public boolean taken()
    {
        return !grade.equals("");
    }


    public boolean equals(Object other)
    {
        boolean result = false;
        if (other instanceof Course)
        {
            Course otherCourse = (Course) other;
            if (prefix.equals(otherCourse.getPrefix()) &&
                    number == otherCourse.getNumber())
                result = true;
        }
        return result;
    }

    public String toString()
    {
        String result = prefix + " " + number + ": " + title;
        if (!grade.equals(""))
            result += "  [" + grade + "]";
        return result;
    }

    @Override
    public int compareTo(Course course) {
        if (prefix.compareTo(course.getPrefix())>0)
            return 1;
        else
        if (prefix.compareTo(course.getPrefix())==0){
            if (number>course.getNumber())
                return 1;
            else
            if (number == course.getNumber())
                return  0;
            else
                return -1;
        }
        else
            return -1;
    }
}