/*
 * IBusStop.java
 *
 * Created on August 8, 2003, 11:36 PM
 *
 * @author Zuo Yan
 */

package mvc143;

import java.util.Collection;

/** The interface to a bus stop in the bus system model.
 * <p>
 * A bus stop object contains data about a particular bus stop in the bus
 * system model. A bus stop is created with a latitude and longitude postion
 * from the model. Each bus stop contains data about the people currently
 * waiting at the bus stop.
 * <p>
 * Note that instantiation of a new bus stop should only be done in the model,
 * because each model can have a different internal representation.
 */
public interface IBusStop {

    /** Gets the model dependent object identifying this bus stop.
     * <br>
     * Note: it is not a requirement that ids have to be unique
     *
     * @return the object identifying this bus stop
     */
    Object getID();

    /** Indicates whether a bus stop is "equal" to this one
     *
     * @param other the bus stop to compare to
     * @return <code>true</code> if they are the same; <code>false</code> otherwise
     */
    boolean equals(IBusStop other);

    /** Gets the collection of IPerson currently waiting at this bus stop
     * <br>
     * Note: changes to the collection is directly reflected in the model.
     *
     * @return the collection of people waiting
     */
    Collection getWaiting();

    /** Adds a person to wait at this bus stop
     *
     * @param p the person to add
     */
    void add(IPerson p);

    /** Gets the next person in the waiting line of this bus stop
     *
     * @return the next person or <code>null</code> if there is no one waiting
     */
    IPerson getNext();

    /** Removes the next person in line from this bus stop
     *
     * @return the person previously next in line or
     *         <code>null</code> if there was no one waiting
     */
    IPerson removeNext();

    /** Gets the latitude coordinate of this bus stop
     *
     * @return the latitude position
     */
    double getLatitude();

    /** Gets the longitude coordinate of this bus stop
     *
     * @return the longitude position
     */
    double getLongitude();

}