package algs25;
import stdlib.*;
import java.util.Arrays;
/* ***********************************************************************
 *  Compilation:  javac Grade.java
 *  Execution:    java Grade
 *
 *  Illustrates implementation of Comparable interface
 *
 *************************************************************************/

public class XGrade implements Comparable<XGrade> {
  private final String grade;

  public XGrade(String grade) {
    this.grade = grade;
    if (gpa() < 0.0) throw new Error("Illegal grade");
  }

  public double gpa() {
    if (grade.equals("A"))  return 4.00;
    if (grade.equals("B"))  return 3.00;
    if (grade.equals("C"))  return 2.00;
    if (grade.equals("D"))  return 1.00;
    if (grade.equals("F"))  return 0.00;
    if (grade.equals("B+")) return 3.33;
    if (grade.equals("C+")) return 2.33;
    if (grade.equals("A-")) return 3.67;
    if (grade.equals("B-")) return 2.67;
    if (grade.equals("C-")) return 1.67;
    return -1.0;
  }

  public int compareTo(XGrade w) {
    XGrade v = this;
    if (v.gpa() < w.gpa()) return -1;
    if (v.gpa() > w.gpa()) return +1;
    return 0;
  }

  // use %-2s flag to left justify
  public String toString() {
    return String.format("%-2s %3.2f", grade, gpa());
  }


  // test client
  public static void main(String[] args) {
    XGrade[] grades = new XGrade[8];
    grades[0] = new XGrade("B+");
    grades[1] = new XGrade("A");
    grades[2] = new XGrade("C+");
    grades[3] = new XGrade("B-");
    grades[4] = new XGrade("A-");
    grades[5] = new XGrade("D");
    grades[6] = new XGrade("F");
    grades[7] = new XGrade("A-");


    StdOut.println("Unsorted");
    for (XGrade grade2 : grades)
      StdOut.println(grade2);
    StdOut.println();

    StdOut.println("Sorted");
    Arrays.sort(grades);
    for (XGrade grade2 : grades)
      StdOut.println(grade2);
  }

}