package envoy.server.data;

import java.util.*;

import javax.persistence.*;

/**
 * Defines a message that has been deleted.
 *
 * @author Leon Hofmeister
 * @since Envoy Server v0.3-beta
 */
@Entity
@Table(name = "deletionEvents")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
public final class MessageDeletion {

	@Id
	@GeneratedValue
	protected long messageID;

	@ManyToOne(targetEntity = User.class)
	protected Set<User> recipientsToInform;

	/**
	 * Creates an instance of {@code DeletionEvent}.
	 *
	 * @since Envoy Server v0.3-beta
	 */
	public MessageDeletion() {}

	/**
	 * Creates an instance of {@code MessageDeletion}.
	 *
	 * @param messageID          the ID of the message
	 * @param recipientsToInform the recipientsToInform of the message<br>
	 *                           <strong>that have not yet been notified of its
	 *                           deletion</strong>
	 * @since Envoy Server v0.3-beta
	 */
	public MessageDeletion(long messageID, Set<User> recipientsToInform) {
		this.messageID			= messageID;
		this.recipientsToInform	= recipientsToInform;
	}

	/**
	 * @return the messageID
	 * @since Envoy Server v0.3-beta
	 */
	public long getMessageID() { return messageID; }

	/**
	 * @param messageID the messageID to set
	 * @since Envoy Server v0.3-beta
	 */
	public void setMessageID(long messageID) { this.messageID = messageID; }

	/**
	 * @return the recipients that have yet to be informed
	 * @since Envoy Server v0.3-beta
	 */
	public Set<User> getRecipientsToInform() { return recipientsToInform; }

	/**
	 * @param recipientsToInform the recipients that have yet to be informed
	 * @since Envoy Server v0.3-beta
	 */
	public void setRecipientsToInform(Set<User> recipientsToInform) { this.recipientsToInform = recipientsToInform; }

	/**
	 * @param user the user who has been informed of the message deletion
	 * @since Envoy Server v0.3-beta
	 */
	public void recipientInformed(User user) { recipientsToInform.remove(user); }

	/**
	 * @param users the users that have been informed of the message deletion
	 * @since Envoy Server v0.3-beta
	 */
	public void recipientInformed(Collection<User> users) { recipientsToInform.removeAll(users); }
}