envoy/src/main/java/envoy/client/ui/Startup.java

package envoy.client.ui;

import java.awt.EventQueue;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.SwingUtilities;

import envoy.client.Config;
import envoy.client.Settings;
import envoy.client.data.*;
import envoy.client.net.Client;
import envoy.client.net.WriteProxy;
import envoy.client.util.EnvoyLog;
import envoy.data.LoginCredentials;
import envoy.data.Message;
import envoy.data.User;
import envoy.exception.EnvoyException;

/**
 * Starts the Envoy client and prompts the user to enter their name.<br>
 * <br>
 * Project: <strong>envoy-client</strong><br>
 * File: <strong>Startup.java</strong><br>
 * Created: <strong>12 Oct 2019</strong><br>
 *
 * @author Leon Hofmeister
 * @author Maximilian K&auml;fer
 * @author Kai S. K. Engelbart
 * @since Envoy v0.1-alpha
 */
public class Startup {

	private static ChatWindow chatWindow;

	private static final Logger logger = EnvoyLog.getLogger(Startup.class.getSimpleName());

	/**
	 * Loads the application by first loading the configuration, then acquiring a
	 * user name and connecting to the server. If the server cannot be reached,
	 * offline mode is entered if possible. After that, a {@link ChatWindow}
	 * instance is initialized and then displayed to the user. Upon application
	 * exit, settings and the local database are saved.
	 *
	 * @param args the command line arguments may contain configuration parameters
	 *             and are parsed by the {@link Config} class
	 * @since Envoy v0.1-alpha
	 */
	public static void main(String[] args) {
		Config config = Config.getInstance();

		SwingUtilities.invokeLater(() -> chatWindow = new ChatWindow());

		try {
			// Load the configuration from client.properties first
			config.load();

			// Override configuration values with command line arguments
			if (args.length > 0) config.load(args);

			// Check if all configuration values have been initialized
			if (!config.isInitialized()) throw new EnvoyException("Server or port are not defined");
		} catch (Exception e) {
			JOptionPane
				.showMessageDialog(null, "Error loading configuration values:\n" + e.toString(), "Configuration error", JOptionPane.ERROR_MESSAGE);
			e.printStackTrace();
			System.exit(1);
		}

		// Set new logger levels loaded from config
		EnvoyLog.setFileLevelBarrier(config.getFileLevelBarrier());
		EnvoyLog.setConsoleLevelBarrier(config.getConsoleLevelBarrier());

		// Ask the user for their user name and password
		LoginCredentials credentials = new LoginDialog().getCredentials();

		if (credentials == null) {
			logger.info("The login process has been aborted by the user. Exiting...");
			System.exit(0);
		}

		// Initialize the local database
		LocalDb localDb;
		if (config.isIgnoreLocalDB()) {
			localDb = new TransientLocalDb();
			JOptionPane.showMessageDialog(null,
					"Ignoring local database.\nMessages will not be saved!",
					"Local database warning",
					JOptionPane.WARNING_MESSAGE);
		} else try {
			localDb = new PersistentLocalDb(new File(config.getHomeDirectory(), config.getLocalDB().getPath()));
		} catch (IOException e3) {
			logger.log(Level.SEVERE, "Could not initialize local database", e3);
			JOptionPane
				.showMessageDialog(null, "Could not initialize local database!\n" + e3.toString(), "Local database error", JOptionPane.ERROR_MESSAGE);
			System.exit(1);
			return;
		}

		SwingUtilities.invokeLater(() -> chatWindow.setVisible(true));

		// Acquire the client user (with ID) either from the server or from the local
		// database, which triggers offline mode
		Client			client	= new Client();
		Cache<Message>	cache	= null;
		try {
			// Try entering online mode first
			localDb.loadIdGenerator();
			cache = client.onlineInit(credentials, localDb);
		} catch (Exception e1) {
			logger.warning("Could not connect to server. Trying offline mode...");
			e1.printStackTrace();
			try {
				// Try entering offline mode
				localDb.loadUsers();
				User clientUser = localDb.getUsers().get(credentials.getName());
				if (clientUser == null) throw new EnvoyException("Could not enter offline mode: user name unknown");
				client.setSender(clientUser);
				JOptionPane.showMessageDialog(null,
						"A connection to the server could not be established. Starting in offline mode.\n" + e1,
						"Connection error",
						JOptionPane.WARNING_MESSAGE);
			} catch (Exception e2) {
				JOptionPane.showMessageDialog(null, e2.toString(), "Client error", JOptionPane.ERROR_MESSAGE);
				System.exit(1);
				return;
			}
		}

		// Set client user in local database
		localDb.setUser(client.getSender());

		// Initialize chats in local database
		try {
			localDb.initializeUserStorage();
			localDb.loadChats();
		} catch (FileNotFoundException e) {
			// The local database file has not yet been created, probably first login
		} catch (Exception e) {
			e.printStackTrace();
			JOptionPane.showMessageDialog(null,
					"Error while loading local database: " + e + "\nChats might not be stored locally.",
					"Local DB error",
					JOptionPane.WARNING_MESSAGE);
		}

		// Initialize write proxy
		final WriteProxy writeProxy = client.createWriteProxy(localDb);

		// Save all users to the local database and flush cache
		if (client.isOnline()) {
			localDb.setUsers(client.getUsers());
			writeProxy.flushCache();
		}

		// Display ChatWindow and StatusTrayIcon
		EventQueue.invokeLater(() -> {
			try {
				chatWindow.initContent(client, localDb, writeProxy);

				try {
					new StatusTrayIcon(chatWindow).show();

					// If the tray icon is supported and corresponding settings is set, hide the
					// chat window on close
					Settings.getInstance()
						.getItems()
						.get("onCloseMode")
						.setChangeHandler((onCloseMode) -> chatWindow
							.setDefaultCloseOperation((Boolean) onCloseMode ? JFrame.HIDE_ON_CLOSE : JFrame.EXIT_ON_CLOSE));
				} catch (EnvoyException e) {
					logger.warning("The StatusTrayIcon is not supported on this platform!");
				}
			} catch (Exception e) {
				e.printStackTrace();
			}
		});

		// Relay unread messages from cache
		if (cache != null) cache.relay();

		// Save Settings and PersistentLocalDb on shutdown
		Runtime.getRuntime().addShutdownHook(new Thread(() -> {
			try {
				logger.info("Closing connection...");
				client.close();

				logger.info("Saving local database and settings...");
				localDb.save();
				Settings.getInstance().save();
			} catch (Exception e) {
				logger.log(Level.SEVERE, "Unable to save local files", e);
			}
		}));
	}
}