ChatBox.java

package org.vaadin.chatbox;

import java.util.ArrayList;
import java.util.List;

import org.vaadin.chatbox.SharedChat.ChatListener;
import org.vaadin.chatbox.client.ChatBoxClientRpc;
import org.vaadin.chatbox.client.ChatBoxServerRpc;
import org.vaadin.chatbox.client.ChatBoxState;
import org.vaadin.chatbox.client.ChatLine;
import org.vaadin.chatbox.client.ChatUser;

import com.vaadin.annotations.StyleSheet;
import com.vaadin.server.VaadinSession;

@StyleSheet("chatbox.css")
@SuppressWarnings("serial")
public class ChatBox extends com.vaadin.ui.AbstractComponent implements
		ChatListener {

	// To process events from the client, we implement ServerRpc
	private ChatBoxServerRpc rpc = new ChatBoxServerRpc() {
		@Override
		public void lineAdded(ChatBoxState.Line line) {
			chat.addLine(ChatBoxState.Line.convert(line));
		}
	};

	private SharedChat chat;

	private int numFrozenLinesOnClient = 0;

	public ChatBox(SharedChat chat) {
		super();
		setWidth("200px"); // ?
		setHeight("200px"); // ?
		this.chat = chat;
		registerRpc(rpc);
	}

	public void setUser(ChatUser user) {
		getState(true).user = ChatBoxState.User.convert(user);
	}

	public void setShowSendButton(boolean show) {
		getState(true).showSendButton = show;
	}

	@Override
	public void attach() {
		super.attach();
		chat.addListener(this);
	}

	@Override
	public void detach() {
		chat.removeListener(this);
		super.detach();
	}

	@Override
	public ChatBoxState getState(boolean markAsDirty) {
		return (ChatBoxState) super.getState(markAsDirty);
	}

	@Override
	public ChatBoxState getState() {
		return (ChatBoxState) super.getState();
	}

	@Override
	public void lineAdded(ChatLine line) {
		// TODO: not exactly sure how we should sync here...
		VaadinSession session = getSession();
		if (session==null) {
			return;
		}
		session.access(new Runnable() {
			@Override
			public void run() {
				ChatBox.this.markAsDirty();
			}
		});
	}

	@Override
	public void beforeClientResponse(boolean initial) {
		super.beforeClientResponse(initial);

		if (initial) {
			numFrozenLinesOnClient = 0;
		}

		List<ChatLine> lines = chat
				.getLinesStartingFrom(numFrozenLinesOnClient);
		if (!lines.isEmpty()) {
			numFrozenLinesOnClient += lines.size();
			ArrayList<ChatBoxState.Line> lis = new ArrayList<ChatBoxState.Line>(
					lines.size());
			for (ChatLine line : lines) {
				lis.add(ChatBoxState.Line.convert(line));
			}
			getRpcProxy(ChatBoxClientRpc.class).addLines(lis);
		}
	}

	public void focusToInputField() {
		getRpcProxy(ChatBoxClientRpc.class).focus();
	}
}