public class hw10 {
    public static void main(String[] args) {
        AirTicketSystem ticketSystem = new AirTicketSystem();
        System.out.println(ticketSystem.toString());
        ticketSystem.assignedTo();
        ticketSystem.exchange();
        ticketSystem.lock();
        ticketSystem.timeOut();
        ticketSystem.lock();
        ticketSystem.unlock();
        ticketSystem.lock();
        ticketSystem.buy();
    }
}

class AirTicketSystem {
    State available;
    State locked;
    State sold;
    State state;

    public AirTicketSystem() {
        available = new Available(this);
        locked = new Locked(this);
        sold = new Sold(this);
        state = available;
    }

    public void assignedTo() {
        state.assignedTo();
    }

    public void timeOut() {
        state.timeOut();
    }

    public void lock() {
        state.lock();
    }

    public void unlock() {
        state.unlock();
    }

    public void buy() {
        state.buy();
    }

    public void exchange() {
        state.exchange();

    }

    public void setState(State state) {
        this.state = state;
    }

    public State getAvailable() {
        return available;
    }

    public State getLocked() {
        return locked;
    }

    public State getSold() {
        return sold;
    }

    public String toString() {
        StringBuffer result = new StringBuffer();
        result.append("\nAir Ticket System #2022");
        result.append("\nThe current state  is:  " + state + "\n");
        return result.toString();
    }
}

interface State {
    public void assignedTo();

    public void timeOut();

    public void lock();

    public void unlock();

    public void buy();

    public void exchange();
}

class Available implements State {
    private AirTicketSystem ats;

    public Available(AirTicketSystem ats) {
        this.ats = ats;
    }

    public void assignedTo() {
        System.out.println("Available=>Sold");
        ats.setState(ats.getSold());
    }

    public void timeOut() {
        System.out.println("No timeOut");
    }

    public void lock() {
        System.out.println("Available=>Locked");
        ats.setState(ats.getLocked());
    }

    public void unlock() {
        System.out.println("No unlock");
    }

    public void buy() {
        System.out.println("No buy");
    }

    public void exchange() {
        System.out.println("No exchange");
    }

    public String toString() {
        return "The ticket is available";
    }
}

class Locked implements State {
    private AirTicketSystem ats;

    public Locked(AirTicketSystem ats) {
        this.ats = ats;
    }

    public void assignedTo() {
        System.out.println("No assignedTo");
    }

    public void timeOut() {
        System.out.println("Locked=>Available");
        ats.setState(ats.getAvailable());
    }

    public void lock() {
        System.out.println("No lock");
    }

    public void unlock() {
        System.out.println("Locked=>Available");
        ats.setState(ats.getAvailable());
    }

    public void buy() {
        System.out.println("Locked=>Sold");
        ats.setState(ats.getSold());
    }

    public void exchange() {
        System.out.println("No exchange");

    }

    public String toString() {
        return "The ticket is Locked";
    }
}

class Sold implements State {
    private AirTicketSystem ats;

    public Sold(AirTicketSystem ats) {
        this.ats = ats;
    }

    public void assignedTo() {
        System.out.println("No assignedTo");
    }

    public void timeOut() {
        System.out.println("No timeOut");
    }

    public void lock() {
        System.out.println("No lock");
    }

    public void unlock() {
        System.out.println("No unlock");
    }

    public void buy() {
        System.out.println("No buy");
    }

    public void exchange() {
        System.out.println("Sold=>Available");
        ats.setState(ats.getAvailable());
    }

    public String toString() {
        return "The ticket is Sold";
    }
}