import java.util.Comparator;

/**
 * Class Person is a class to represent people
 *
 * @author Bill Kraynek
 */
public class Person implements Comparable<Person> {

    private String firstName;
    private String lastName;
    private String idNumber;

    /**
     * A constructor from two Strings
     *
     * @param first is the person first name
     * @param last is the person's last name
     */
    public Person(String idNumber, String first, String last) {
        this.idNumber = idNumber;
        firstName = first;
        lastName = last;
    } // end constructor

    // accessors
    /**
     * Retrieve the idNumber
     *
     * @return the idNumber as a String
     */
    public String getIdNumber() {
        return idNumber;
    }

    /**
     * Retrieve the first name
     *
     * @return the first name as a String
     */
    public String getFirstName() {
        return firstName;
    }

    /**
     * Retrieve the last name
     *
     * @return the last name as a String
     */
    public String getLastName() {
        return lastName;
    }

    // modifier
    /**
     * Change the last name
     *
     * @param newName is the new last name
     */
    public void setLastName(String newName) {
        lastName = newName;
    }

    /**
     * Change the first name
     *
     * @param newName is the new first name
     */
    public void setFirstName(String newName) {
        firstName = newName;
    }

    /**
     * Person objects are equal if both names are equal
     *
     * @return true if both names are equal; false otherwise
     */
    public boolean equals(Object aPerson) {
        if (!(aPerson instanceof Person)) {
            return false;
        }
        return getIdNumber().equals(((Person) aPerson).getIdNumber());
    } // end equals

    // From the Java API: Note that it is generally necessary to override the hashCode method whenever this method
    // is overridden, so as to maintain the general contract for the hashCode method, which states that equal objects
    // must have equal hash codes
    /**
     * Returns an int value asociated with this object
     *
     * @return a hash code value for the object.
	  *
     */
    public int hashCode() {
        return getIdNumber().hashCode();
    } // end hashCode

    /**
     * Compares this Person to another Person using String compareTo on lastName
     * and then firstName and then id
     *
     * @param rhs the Person to be compared
     * @return an int < 0 if less; an int == 0 if equal; an int >0 if greater
     */
    public int compareTo(Person rhs) {
        String last;
        if (getLastName().equals("")) {
            last = getFirstName();
        } else {
            last = getLastName();
        }
        String rhsLast;
        if (rhs.getLastName().equals("")) {
            rhsLast = rhs.getFirstName();
        } else {
            rhsLast = rhs.getLastName();
        }
        int lastCompare = last.compareTo(rhsLast);
        if (lastCompare != 0) {
            return lastCompare;
        }
        int firstCompare = getFirstName().compareTo(((Person) rhs).getFirstName());
        if (firstCompare != 0) {
            return firstCompare;
        }
        return getIdNumber().compareTo(((Person) rhs).getIdNumber());
    } // end compareTo

    /**
     * Returns a String representation of the data in class Person
     *
     * @return a string of the objects in Person
     */
    public String toString() {
        return idNumber + " " + (lastName.equals("") ? "" : (lastName + " ")) + firstName;
    }
    // This class implements compare so the order is by idNumber.
    static class idNumberOrder implements Comparator<Person> {

        public int compare(Person personA, Person personB) {
            return personA.getIdNumber().compareTo(personB.getIdNumber());
        } // end compare
    } // end idNumberOrder
} // end Person