envoy/src/main/java/envoy/client/data/Chat.java

package envoy.client.data;

import java.io.IOException;
import java.io.Serializable;
import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;

import envoy.client.net.WriteProxy;
import envoy.data.*;
import envoy.data.Message.MessageStatus;
import envoy.event.GroupMessageStatusChange;
import envoy.event.MessageStatusChange;

/**
 * Represents a chat between two {@link User}s
 * as a list of {@link Message} objects.
 * <p>
 * Project: <strong>envoy-client</strong><br>
 * File: <strong>Chat.java</strong><br>
 * Created: <strong>19 Oct 2019</strong><br>
 *
 * @author Maximilian K&auml;fer
 * @author Leon Hofmeister
 * @author Kai S. K. Engelbart
 * @since Envoy Client v0.1-alpha
 */
public final class Chat implements Serializable {

	private final Contact		recipient;
	private final Contact		sender;
	private final List<Message>	messages	= new ArrayList<>();

	private static final long serialVersionUID = 1L;

	/**
	 * Provides the list of messages that the recipient receives.
	 * <p>
	 * Saves the Messages in the corresponding chat at that Point.
	 *
	 * @param recipient the user who receives the messages
	 * @param sender    the user who is logged in as sender on this instance of
	 *                  envoy.client
	 * @since Envoy Client v0.1-alpha
	 */
	public Chat(Contact recipient, Contact sender) {
		this.recipient	= recipient;
		this.sender		= sender;
	}

	@Override
	public String toString() { return String.format("Chat[recipient=%s,messages=%d]", recipient, messages.size()); }

	/**
	 * Generates a hash code based on the recipient.
	 * 
	 * @since Envoy Client v0.1-beta
	 */
	@Override
	public int hashCode() { return Objects.hash(recipient); }

	/**
	 * Tests equality to another object based on the recipient.
	 * 
	 * @since Envoy Client v0.1-beta
	 */
	@Override
	public boolean equals(Object obj) {
		if (this == obj) return true;
		if (!(obj instanceof Chat)) return false;
		Chat other = (Chat) obj;
		return Objects.equals(recipient, other.recipient);
	}

	/**
	 * Sets the status of all chat messages received from the recipient to
	 * {@code READ} starting from the bottom and stopping once a read message is
	 * found.
	 *
	 * @param writeProxy the write proxy instance used to notify the server about
	 *                   the message status changes
	 * @throws IOException if a {@link MessageStatusChange} could not be
	 *                     delivered to the server
	 * @since Envoy Client v0.3-alpha
	 */
	public void read(WriteProxy writeProxy) throws IOException {
		for (int i = messages.size() - 1; i >= 0; --i) {
			final Message m = messages.get(i);
			if(m.getClass().equals(GroupMessage.class)) {
				GroupMessage g = (GroupMessage) m;
				if (g.getSenderID() != sender.getID()) {
					if (g.getMemberStatuses().get(sender.getID()) == MessageStatus.READ) break;
					else {
						g.getMemberStatuses().replace(sender.getID(), MessageStatus.READ);
						writeProxy.writeMessageStatusChange(
								new GroupMessageStatusChange(g.getID(), MessageStatus.READ, LocalDateTime.now(), sender.getID()));
					}
				}
			}else {
				if (m.getSenderID() == recipient.getID()) if (m.getStatus() == MessageStatus.READ) break;
				else {
					m.setStatus(MessageStatus.READ);
					writeProxy.writeMessageStatusChange(new MessageStatusChange(m));
				}
			}
		}
	}

	/**
	 * @return {@code true} if the newest message received in the chat doesn't have
	 *         the status {@code READ}
	 * @since Envoy Client v0.3-alpha
	 */
	public boolean isUnread() { return !messages.isEmpty() && messages.get(messages.size() - 1).getStatus() != MessageStatus.READ; }

	/**
	 * Inserts a message at the correct place according to its creation date.
	 * 
	 * @param message the message to insert
	 * @since Envoy Client v0.1-beta
	 */
	public void insert(Message message) {
		for (int i = messages.size() - 1; i >= 0; --i)
			if (message.getCreationDate().isAfter(messages.get(i).getCreationDate())) {
				messages.add(i + 1, message);
				return;
			}
		messages.add(0, message);
	}

	/**
	 * @return all messages in the current chat
	 * @since Envoy Client v0.1-beta
	 */
	public List<Message> getMessages() { return messages; }

	/**
	 * @return the recipient of a message
	 * @since Envoy Client v0.1-alpha
	 */
	public Contact getRecipient() { return recipient; }

	/**
	 * @return whether this {@link Chat} points at a {@link User}
	 * @since Envoy Client v0.1-beta
	 */
	public boolean isUserChat() { return recipient instanceof User; }

	/**
	 * @return whether this {@link Chat} points at a {@link Group}
	 * @since Envoy Client v0.1-beta
	 */
	public boolean isGroupChat() { return recipient instanceof Group; }
}