package envoy.data;

import java.io.Serializable;
import java.util.*;

/**
 * This class is the superclass for both {@link User} and {@link Group}.<br>
 * It provides an id and a name for each user and group.<br>
 *
 * @author Leon Hofmeister
 * @since Envoy v0.1-beta
 */
public abstract class Contact implements Serializable {

	protected final long								id;
	protected final transient Set<? extends Contact>	contacts;

	protected String name;

	private static final long serialVersionUID = 0L;

	/**
	 * Creates a new instance of a {@link Contact}.
	 *
	 * @param id       the ID of this contact
	 * @param name     the name of this contact
	 * @param contacts the contacts of this {@link Contact}
	 * @since Envoy Common v0.1-beta
	 */
	public Contact(long id, String name, Set<? extends Contact> contacts) {
		this.id			= id;
		this.name		= name;
		this.contacts	= contacts;
	}

	/**
	 * @return the ID of this {@link Contact}
	 * @since Envoy Common v0.2-alpha
	 */
	public long getID() { return id; }

	/**
	 * @return the name of this {@link Contact}
	 * @since Envoy Common v0.2-alpha
	 */
	public String getName() { return name; }

	/**
	 * @param name the new name of this {@link Contact}
	 * @since Envoy Common v0.1-beta
	 */
	public void setName(String name) { this.name = name; }

	/**
	 * Provides a hash code based on the ID of this contact.
	 *
	 * @since Envoy Common v0.1-beta
	 */
	@Override
	public final int hashCode() {
		return Objects.hash(id);
	}

	/**
	 * Tests equality to another object. If that object is a contact as well, equality is determined
	 * by the ID.
	 *
	 * @param obj the object to test for equality to this contact
	 * @return {code true} if both objects are contacts and have identical IDs
	 */
	@Override
	public final boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (!(obj instanceof Contact))
			return false;
		return id == ((Contact) obj).id;
	}

	/**
	 * @return the contacts of this {@link Contact}
	 * @since Envoy Common v0.1-beta
	 */
	public Set<? extends Contact> getContacts() { return contacts; }
}