// class representing a member of the evil robot army
public class EvilRobot {
    
    /* static class variables --------------- */

    // the leader of the army
    private static EvilRobot fearlessLeader;

    // version number of evil robots
    public static final double ROBOT_VERSION = 3.7;

    private static int numRobots;
    
    // static block -- happens once at beginning of program
    // use to initialize static variables
    // and do other needed setup
    static {
        setNumRobots(0);
        // temp variable, only exists within static block
        EvilRobot fl = new EvilRobot();
        fl.makeLeader();
    }
    
    /* instance variables --------------- */

    private int idNumber;  	// the id of this robot
    private String job;		// this robot's job


    /* constructors --------------- */

    /**
    default constructor
    **/
    public EvilRobot() {
        idNumber = 0;
        job = "jobless";
        setNumRobots(getNumRobots() + 1);
    }

    /**
    constructor with all variables as parameters
    **/
    public EvilRobot(int idNumber_val, String job_val) {
        // call default constructor
        this();
        
        setIdNumber(idNumber_val);
        setJob(job_val);
    }


    /* accessors and mutators --------------- */


    /**
    * Accessor for idNumber
    **/
    public int getIdNumber(){
        return idNumber;
    }


    /**
    * Mutator for idNumber
    **/
    public void setIdNumber(int newvalue){
        if (newvalue >= 0) {
            idNumber = newvalue;
        }
    }

    
    

    /**
    * Accessor for job
    **/
    public String getJob(){
        return job;
    }


    /**
    * Mutator for job
    **/
    public void setJob(String newvalue){
        if (newvalue != null) {
            job = newvalue;
        }
    }

    
    /**
    * Accessor for fearlessLeader
    **/
    public static EvilRobot getFearlessLeader(){
        return fearlessLeader;
    }


    /**
    * Mutator for fearlessLeader
    **/
    public static void setFearlessLeader(EvilRobot newvalue){
        fearlessLeader = newvalue;
    }
    


    /**
    * Accessor for numRobots
    **/
    public static int getNumRobots(){
        return numRobots;
    }


    /**
    * Mutator for numRobots
    * private, cannot be used outside class
    **/
    private static void setNumRobots(int newvalue){
        numRobots = newvalue;
    }
    
    
    /* utility methods --------------- */


    /**
    * represent as a string 
    **/
    public String toString() {
        return "[Robot #" + getIdNumber() + "(ver " + 
        ROBOT_VERSION + "): " + getJob() + "]";
    }

    /* methods --------------- */

    /**
    * make this robot the leader
    **/
    public void makeLeader() {
        setFearlessLeader(this);
        // same as just setJob
        setJob("lead my glorious troops to dominate the universe");
    }
    
    /**
    * check if there is currently a leader
    * if not, volunteer
    **/
    public boolean checkLeader() {
        // if the leader pointer is null
        // I become the leader
        if (getFearlessLeader() == null) {
            makeLeader();
            return true;
        }
        return false;
    }

    /**
    * get a job from the leader
    * (or become leader)
    **/
    public void getAJob() {
        // check if there is a leader
        // if there was (so I didn't volunteer)
        if (!checkLeader()) {
            // get a job from the leader
            getFearlessLeader().assignJob(this);
        }
    }
    
    
    /**
    * assign a job to a robot
    **/
    public void assignJob(EvilRobot rob) {
        // if I'm not the leader, I can't assign jobs
        if (this == getFearlessLeader()) {
            rob.setJob(generateJob());
        }
    }


    /**
    * randomly choose a job
    * this isn't specific to one robot
    * so make static
    **/
    public static String generateJob() {
        // get a random number
        int choice = (int)(Math.random() * 3.0);
        // return string based on choice number
        switch (choice) {
        case 0: return "go bzzzt";
        case 1: return "build rockets";
        case 2: return "dig pit traps";
        default: return "shoot lasers";
        }			
    }

}