Added better dependency injection mechanism and purified LoginScene

one thing could for whatever reason not be avoided: Even though the
processors of the caches inside WriteProxy are initialized, they somehow
get "de-initialized" and have to be initialized again...

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

@@ -51,6 +51,12 @@ public final class Cache<T> implements Consumer<T>, Serializable {
 	 */
 	public void setProcessor(Consumer<T> processor) { this.processor = processor; }
 
+	/**
+	 * @return the processor
+	 * @since Envoy Client v0.2-beta
+	 */
+	public Consumer<T> getProcessor() { return processor; }
+
 	/**
 	 * Relays all cached elements to the processor.
 	 *

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

@@ -0,0 +1,97 @@
+package envoy.client.data;
+
+import javafx.stage.Stage;
+
+import envoy.client.net.Client;
+import envoy.client.net.WriteProxy;
+import envoy.client.ui.SceneContext;
+
+/**
+ * Provides access to commonly used objects.
+ * <p>
+ * Project: <strong>client</strong><br>
+ * File: <strong>Context.java</strong><br>
+ * Created: <strong>01.09.2020</strong><br>
+ *
+ * @author Leon Hofmeister
+ * @since Envoy Client v0.2-beta
+ */
+public class Context {
+
+	private final Client client = new Client();
+
+	private WriteProxy writeProxy;
+
+	private LocalDB localDB;
+
+	private Stage stage;
+
+	private SceneContext sceneContext;
+
+	private static final Context instance = new Context();
+
+	/**
+	 * @return the instance of {@code Context} used throughout Envoy
+	 * @since Envoy Client v0.2-beta
+	 */
+	public static Context getInstance() { return instance; }
+
+	/**
+	 * @return the localDB
+	 * @since Envoy Client v0.2-beta
+	 */
+	public LocalDB getLocalDB() { return localDB; }
+
+	/**
+	 * @param localDB the localDB to set
+	 * @since Envoy Client v0.2-beta
+	 */
+	public void setLocalDB(LocalDB localDB) { this.localDB = localDB; }
+
+	/**
+	 * @return the sceneContext
+	 * @since Envoy Client v0.2-beta
+	 */
+	public SceneContext getSceneContext() { return sceneContext; }
+
+	/**
+	 * @param sceneContext the sceneContext to set. Additionally sets the stage.
+	 * @since Envoy Client v0.2-beta
+	 */
+	public void setSceneContext(SceneContext sceneContext) {
+		this.sceneContext	= sceneContext;
+		stage				= sceneContext.getStage();
+	}
+
+	/**
+	 * @return the client
+	 * @since Envoy Client v0.2-beta
+	 */
+	public Client getClient() { return client; }
+
+	/**
+	 * @return the writeProxy
+	 * @since Envoy Client v0.2-beta
+	 */
+	public WriteProxy getWriteProxy() { return writeProxy; }
+
+	/**
+	 * @return the stage
+	 * @since Envoy Client v0.2-beta
+	 */
+	public Stage getStage() { return stage; }
+
+	private Context() {}
+
+	/**
+	 * @param writeProxy the writeProxy to set
+	 * @since Envoy Client v0.2-beta
+	 */
+	public void setWriteProxy(WriteProxy writeProxy) { this.writeProxy = writeProxy; }
+
+	/**
+	 * @param stage the stage to set
+	 * @since Envoy Client v0.2-beta
+	 */
+	public void setStage(Stage stage) { this.stage = stage; }
+}

client/src/main/java/envoy/client/event/BackEvent.java

@@ -3,8 +3,9 @@ package envoy.client.event;
 import envoy.event.Event.Valueless;
 
 /**
- * This event serves the purpose to trigger the tab change to tab 0 in {@link ChatScene}.<p>
+ * This event serves the purpose to trigger the tab change to tab 0 in
- * 
+ * {@link envoy.client.ui.controller.ChatScene}.
+ * <p>
  * Project: <strong>client</strong><br>
  * File: <strong>BackEvent.java</strong><br>
  * Created: <strong>23.08.2020</strong><br>
@@ -12,7 +13,7 @@ import envoy.event.Event.Valueless;
  * @author Maximilian K&auml;fer
  * @since Envoy Client v0.2-beta
  */
-public class BackEvent extends Valueless{
+public class BackEvent extends Valueless {
 
 	private static final long serialVersionUID = 0L;
 }

client/src/main/java/envoy/client/event/LoadGroupCreationEvent.java

@@ -1,27 +0,0 @@
-package envoy.client.event;
-
-import envoy.client.data.LocalDB;
-import envoy.client.ui.controller.ChatScene;
-import envoy.event.Event;
-
-/**
- * This event carries an instance of {@link LocalDB} so the groupCreationTab has the most recent version of the contactList. <br>
- * It is triggered as soon as the corresponding button in {@link ChatScene} is clicked. <p>
- * 
- * Project: <strong>client</strong><br>
- * File: <strong>LoadGroupCreationEvent.java</strong><br>
- * Created: <strong>23.08.2020</strong><br>
- *
- * @author Maximilian K&auml;fer
- * @since Envoy Client v0.2-beta
- */
-public class LoadGroupCreationEvent extends Event<LocalDB>{
-
-	private static final long serialVersionUID = 0L;
-
-	/**
-	 * @param value the localDB
-	 * @since Envoy Client v0.2-beta
-	 */
-	public LoadGroupCreationEvent(LocalDB value) { super(value); }
-}

client/src/main/java/envoy/client/net/WriteProxy.java

@@ -5,6 +5,7 @@ import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import envoy.client.data.Cache;
+import envoy.client.data.Context;
 import envoy.client.data.LocalDB;
 import envoy.data.Message;
 import envoy.event.MessageStatusChange;
@@ -24,8 +25,8 @@ import envoy.util.EnvoyLog;
  */
 public final class WriteProxy {
 
-	private final Client	client;
+	private final Client	client	= Context.getInstance().getClient();
-	private final LocalDB	localDB;
+	private final LocalDB	localDB	= Context.getInstance().getLocalDB();
 
 	private static final Logger logger = EnvoyLog.getLogger(WriteProxy.class);
 
@@ -33,15 +34,9 @@ public final class WriteProxy {
 	 * Initializes a write proxy using a client and a local database. The
 	 * corresponding cache processors are injected into the caches.
 	 *
-	 * @param client  the client used to send messages and message status change
-	 *                events
-	 * @param localDB the local database used to cache messages and message status
-	 *                change events
 	 * @since Envoy Client v0.3-alpha
 	 */
-	public WriteProxy(Client client, LocalDB localDB) {
+	public WriteProxy() {
-		this.client		= client;
-		this.localDB	= localDB;
 
 		// Initialize cache processors for messages and message status change events
 		localDB.getCacheMap().get(Message.class).setProcessor(msg -> {
@@ -68,7 +63,32 @@ public final class WriteProxy {
 	 *
 	 * @since Envoy Client v0.3-alpha
 	 */
-	public void flushCache() { localDB.getCacheMap().getMap().values().forEach(Cache::relay); }
+	public void flushCache() {
+
+		// supplying default values if not initialized - for some reason these
+		// processors can be not defined...
+		final var messageCache = localDB.getCacheMap().get(Message.class);
+		if (messageCache.getProcessor() == null) messageCache.setProcessor(msg -> {
+			try {
+				logger.log(Level.FINER, "Sending cached " + msg);
+				client.sendMessage(msg);
+			} catch (final IOException e) {
+				logger.log(Level.SEVERE, "Could not send cached message: ", e);
+			}
+		});
+		final var messageStatusCache = localDB.getCacheMap().get(MessageStatusChange.class);
+		if (messageStatusCache.getProcessor() == null) messageStatusCache.setProcessor(evt -> {
+			logger.log(Level.FINER, "Sending cached " + evt);
+			try {
+				client.sendEvent(evt);
+			} catch (final IOException e) {
+				logger.log(Level.SEVERE, "Could not send cached message status change event: ", e);
+			}
+		});
+
+		// sending these solely local objects to the server
+		localDB.getCacheMap().getMap().values().forEach(Cache::relay);
+	}
 
 	/**
 	 * Delivers a message to the server if online. Otherwise the message is cached

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

@@ -124,8 +124,8 @@ public final class SceneContext {
 	 * @since Envoy Client v0.1-beta
 	 */
 	public void pop() {
-		sceneStack.pop();
+		if (!sceneStack.isEmpty()) sceneStack.pop();
-		controllerStack.pop();
+		if (!controllerStack.isEmpty()) controllerStack.pop();
 		if (!sceneStack.isEmpty()) {
 			final var newScene = sceneStack.peek();
 			stage.setScene(newScene);

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

@@ -1,7 +1,10 @@
 package envoy.client.ui;
 
 import java.io.File;
+import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.time.Instant;
+import java.util.concurrent.TimeoutException;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
@@ -12,12 +15,14 @@ import javafx.stage.Stage;
 
 import envoy.client.data.*;
 import envoy.client.net.Client;
+import envoy.client.net.WriteProxy;
 import envoy.client.ui.SceneContext.SceneInfo;
 import envoy.client.ui.controller.LoginScene;
-import envoy.data.GroupMessage;
+import envoy.data.*;
-import envoy.data.Message;
+import envoy.data.User.UserStatus;
 import envoy.event.GroupMessageStatusChange;
 import envoy.event.MessageStatusChange;
+import envoy.exception.EnvoyException;
 import envoy.util.EnvoyLog;
 
 /**
@@ -40,9 +45,10 @@ public final class Startup extends Application {
 	 */
 	public static final String VERSION = "0.1-beta";
 
-	private LocalDB	localDB;
+	private static LocalDB localDB;
-	private Client	client;
 
+	private static final Context		context	= Context.getInstance();
+	private static final Client			client	= context.getClient();
 	private static final ClientConfig	config	= ClientConfig.getInstance();
 	private static final Logger			logger	= EnvoyLog.getLogger(Startup.class);
 
@@ -76,22 +82,142 @@ public final class Startup extends Application {
 			System.exit(1);
 			return;
 		}
-
+		// Prepare handshake
-		// Initialize client and unread message cache
+		localDB.loadIDGenerator();
-		client = new Client();
+		context.setLocalDB(localDB);
-
-		final var cacheMap = new CacheMap();
-		cacheMap.put(Message.class, new Cache<Message>());
-		cacheMap.put(GroupMessage.class, new Cache<GroupMessage>());
-		cacheMap.put(MessageStatusChange.class, new Cache<MessageStatusChange>());
-		cacheMap.put(GroupMessageStatusChange.class, new Cache<GroupMessageStatusChange>());
 
 		stage.setTitle("Envoy");
 		stage.getIcons().add(IconUtil.loadIcon("envoy_logo"));
 
 		final var sceneContext = new SceneContext(stage);
-		sceneContext.load(SceneInfo.LOGIN_SCENE);
+		context.setSceneContext(sceneContext);
-		sceneContext.<LoginScene>getController().initializeData(client, localDB, cacheMap, sceneContext);
+		context.setWriteProxy(new WriteProxy());
+
+		// Perform automatic login if configured
+		if (config.hasLoginCredentials())
+			performHandshake(new LoginCredentials(config.getUser(), config.getPassword(), false, Startup.VERSION, loadLastSync(config.getUser())));
+		else sceneContext.load(SceneInfo.LOGIN_SCENE);
+	}
+
+	/**
+	 * Tries to perform a Handshake with the server.
+	 *
+	 * @param credentials the credentials to use for the handshake
+	 * @since Envoy Client v0.2-beta
+	 */
+	public static void performHandshake(LoginCredentials credentials) {
+		final var cacheMap = new CacheMap();
+		cacheMap.put(Message.class, new Cache<Message>());
+		cacheMap.put(GroupMessage.class, new Cache<GroupMessage>());
+		cacheMap.put(MessageStatusChange.class, new Cache<MessageStatusChange>());
+		cacheMap.put(GroupMessageStatusChange.class, new Cache<GroupMessageStatusChange>());
+		try {
+			final var client = context.getClient();
+			client.performHandshake(credentials, cacheMap);
+			if (client.isOnline()) {
+				loadChatScene();
+				client.initReceiver(localDB, cacheMap);
+			}
+		} catch (IOException | InterruptedException | TimeoutException e) {
+			logger.log(Level.INFO, "Could not connect to server. Entering offline mode...");
+			attemptOfflineMode(credentials.getIdentifier());
+		}
+	}
+
+	/**
+	 * Attempts to load {@link envoy.client.ui.controller.ChatScene} in offline mode
+	 * for a given user.
+	 *
+	 * @param identifier the identifier of the user - currently his username
+	 * @since Envoy Client v0.2-beta
+	 */
+	public static void attemptOfflineMode(String identifier) {
+		try {
+			// Try entering offline mode
+			localDB.loadUsers();
+			final User clientUser = localDB.getUsers().get(identifier);
+			if (clientUser == null) throw new EnvoyException("Could not enter offline mode: user name unknown");
+			client.setSender(clientUser);
+			loadChatScene();
+		} catch (final Exception e) {
+			new Alert(AlertType.ERROR, "Client error: " + e).showAndWait();
+			logger.log(Level.SEVERE, "Offline mode could not be loaded: ", e);
+			System.exit(1);
+		}
+	}
+
+	/**
+	 * Loads the last known time a user has been online.
+	 *
+	 * @param identifier the identifier of this user - currently his name
+	 * @return the last {@code Instant} at which he has been online
+	 * @since Envoy Client v0.2-beta
+	 */
+	public static Instant loadLastSync(String identifier) {
+		try {
+			localDB.loadUsers();
+			localDB.setUser(localDB.getUsers().get(identifier));
+			localDB.initializeUserStorage();
+			localDB.loadUserData();
+		} catch (final Exception e) {
+			// User storage empty, wrong user name etc. -> default lastSync
+		}
+		return localDB.getLastSync();
+	}
+
+	private static void loadChatScene() {
+
+		// Set client user in local database
+		localDB.setUser(client.getSender());
+
+		// Initialize chats in local database
+		try {
+			localDB.initializeUserStorage();
+			localDB.loadUserData();
+		} catch (final FileNotFoundException e) {
+			// The local database file has not yet been created, probably first login
+		} catch (final Exception e) {
+			new Alert(AlertType.ERROR, "Error while loading local database: " + e + "\nChats will not be stored locally.").showAndWait();
+			logger.log(Level.WARNING, "Could not load local database: ", e);
+		}
+
+		localDB.synchronize();
+
+		if (client.isOnline()) context.getWriteProxy().flushCache();
+		else
+			// Set all contacts to offline mode
+			localDB.getChats()
+				.stream()
+				.map(Chat::getRecipient)
+				.filter(User.class::isInstance)
+				.map(User.class::cast)
+				.forEach(u -> u.setStatus(UserStatus.OFFLINE));
+
+		final var stage = context.getStage();
+		// Load ChatScene
+		context.getSceneContext().pop();
+		stage.setMinHeight(400);
+		stage.setMinWidth(843);
+		context.getSceneContext().load(SceneContext.SceneInfo.CHAT_SCENE);
+		stage.centerOnScreen();
+
+		if (StatusTrayIcon.isSupported()) {
+
+			// Configure hide on close
+			stage.setOnCloseRequest(e -> {
+				if (Settings.getInstance().isHideOnClose()) {
+					stage.setIconified(true);
+					e.consume();
+				}
+			});
+
+			// Initialize status tray icon
+			final var trayIcon = new StatusTrayIcon(stage);
+			Settings.getInstance().getItems().get("hideOnClose").setChangeHandler(c -> {
+				if ((Boolean) c) trayIcon.show();
+				else trayIcon.hide();
+			});
+		}
 	}
 
 	/**
@@ -106,7 +232,7 @@ public final class Startup extends Application {
 			localDB.save(client.isOnline());
 			Settings.getInstance().save();
 
-			logger.log(Level.INFO, "Closing connection...");
+			if (client.isOnline()) logger.log(Level.INFO, "Closing connection...");
 			client.close();
 
 			logger.log(Level.INFO, "Envoy was terminated by its user");

client/src/main/java/envoy/client/ui/controller/ChatScene.java

@@ -29,7 +29,9 @@ import javafx.scene.image.Image;
 import javafx.scene.image.ImageView;
 import javafx.scene.input.KeyCode;
 import javafx.scene.input.KeyEvent;
-import javafx.scene.layout.*;
+import javafx.scene.layout.AnchorPane;
+import javafx.scene.layout.GridPane;
+import javafx.scene.layout.VBox;
 import javafx.scene.paint.Color;
 import javafx.scene.shape.Rectangle;
 import javafx.stage.FileChooser;
@@ -39,13 +41,16 @@ import envoy.client.data.*;
 import envoy.client.data.audio.AudioRecorder;
 import envoy.client.data.commands.SystemCommandBuilder;
 import envoy.client.data.commands.SystemCommandsMap;
-import envoy.client.event.*;
+import envoy.client.event.BackEvent;
+import envoy.client.event.MessageCreationEvent;
+import envoy.client.event.SendEvent;
 import envoy.client.net.Client;
 import envoy.client.net.WriteProxy;
 import envoy.client.ui.*;
-import envoy.client.ui.listcell.*;
+import envoy.client.ui.listcell.ChatControl;
+import envoy.client.ui.listcell.ListCellFactory;
+import envoy.client.ui.listcell.MessageListCell;
 import envoy.client.util.ReflectionUtil;
-import envoy.constant.Tabs;
 import envoy.data.*;
 import envoy.data.Attachment.AttachmentType;
 import envoy.event.*;
@@ -122,42 +127,41 @@ public final class ChatScene implements Restorable {
 
 	@FXML
 	private TextArea contactSearch;
-	
+
 	@FXML
 	private VBox contactOperations;
-	
+
 	@FXML
 	private TabPane tabPane;
-	
+
 	@FXML
 	private Tab contactSearchTab;
-	
+
 	@FXML
 	private Tab groupCreationTab;
 
-	private LocalDB			localDB;
+	private final LocalDB			localDB					= context.getLocalDB();
-	private Client			client;
+	private final Client			client					= context.getClient();
-	private WriteProxy		writeProxy;
+	private final WriteProxy		writeProxy				= context.getWriteProxy();
-	private SceneContext	sceneContext;
+	private final SceneContext		sceneContext			= context.getSceneContext();
+	private final AudioRecorder		recorder				= new AudioRecorder();
+	private final SystemCommandsMap	messageTextAreaCommands	= new SystemCommandsMap();
 
-	private Chat			currentChat;
+	private Chat				currentChat;
-	private AudioRecorder	recorder;
+	private FilteredList<Chat>	chats;
-	private boolean			recording;
+	private boolean				recording;
-	private Attachment		pendingAttachment;
+	private Attachment			pendingAttachment;
-	private boolean postingPermanentlyDisabled;
+	private boolean				postingPermanentlyDisabled;
-
-	private final SystemCommandsMap messageTextAreaCommands = new SystemCommandsMap();
 
 	private static final Settings	settings	= Settings.getInstance();
 	private static final EventBus	eventBus	= EventBus.getInstance();
 	private static final Logger		logger		= EnvoyLog.getLogger(ChatScene.class);
+	private static final Context	context		= Context.getInstance();
 
 	private static final Image	DEFAULT_ATTACHMENT_VIEW_IMAGE	= IconUtil.loadIconThemeSensitive("attachment_present", 20);
 	private static final int	MAX_MESSAGE_LENGTH				= 255;
 	private static final int	DEFAULT_ICON_SIZE				= 16;
 
-	private FilteredList<Chat> chats;
-
 	/**
 	 * Initializes the appearance of certain visual components.
 	 *
@@ -181,24 +185,28 @@ public final class ChatScene implements Restorable {
 		clip.setArcHeight(43);
 		clip.setArcWidth(43);
 		clientProfilePic.setClip(clip);
-		
+
+		chatList.setItems(chats = new FilteredList<>(FXCollections.observableList(localDB.getChats())));
+		contactLabel.setText(localDB.getUser().getName());
+
+		initializeSystemCommandsMap();
+
 		Platform.runLater(() -> {
-			if(client.isOnline()) {
+			if (client.isOnline()) try {
-				try {
+				contactSearchTab.setContent(FXMLLoader.load(new File("src/main/resources/fxml/ContactSearchTab.fxml").toURI().toURL()));
-					contactSearchTab.setContent(FXMLLoader.load(new File("src/main/resources/fxml/ContactSearchTab.fxml").toURI().toURL()));
+				groupCreationTab.setContent(FXMLLoader.load(new File("src/main/resources/fxml/GroupCreationTab.fxml").toURI().toURL()));
-					groupCreationTab.setContent(FXMLLoader.load(new File("src/main/resources/fxml/GroupCreationTab.fxml").toURI().toURL()));
+			} catch (final IOException e2) {
-				} catch (IOException e2) {
+				logger.log(Level.SEVERE, "An error occurred when attempting to load tabs: ", e2);
-					logger.log(Level.SEVERE, "An error occurred when attempting to load tabs: ", e2);
+			}
-				}
+			else {
-			} else {
 				contactSearchTab.setContent(createOfflineNote());
 				groupCreationTab.setContent(createOfflineNote());
 			}
 		});
-		
+
-		//Listen to backEvents
+		// Listen to backEvents
-		eventBus.register(BackEvent.class, e -> tabPane.getSelectionModel().select(Tabs.CONTACT_LIST));
+		eventBus.register(BackEvent.class, e -> tabPane.getSelectionModel().select(Tabs.CONTACT_LIST.ordinal()));
-		
+
 		// Listen to received messages
 		eventBus.register(MessageCreationEvent.class, e -> {
 			final var message = e.get();
@@ -284,15 +292,15 @@ public final class ChatScene implements Restorable {
 
 		eventBus.register(GroupCreationResult.class, e -> Platform.runLater(() -> { newGroupButton.setDisable(!e.get()); }));
 	}
-	
+
 	private AnchorPane createOfflineNote() {
-		AnchorPane anc = new AnchorPane();
+		final var	anc		= new AnchorPane();
-		VBox vBox = new VBox();
+		final var	vBox	= new VBox();
 		vBox.setAlignment(Pos.TOP_CENTER);
 		vBox.setPrefWidth(316);
-		Label label = new Label("You have to be online!");
+		final var label = new Label("You have to be online!");
 		label.setPadding(new Insets(50, 0, 5, 0));
-		Button button = new Button("OK");
+		final var button = new Button("OK");
 		button.setOnAction(e -> eventBus.dispatch(new BackEvent()));
 		vBox.getChildren().add(label);
 		vBox.getChildren().add(button);
@@ -317,34 +325,6 @@ public final class ChatScene implements Restorable {
 		messageTextAreaCommands.add("DABR", builder.build());
 	}
 
-	/**
-	 * Initializes all necessary data via dependency injection-
-	 *
-	 * @param sceneContext the scene context used to load other scenes
-	 * @param localDB      the local database form which chats and users are loaded
-	 * @param client       the client used to request ID generators
-	 * @param writeProxy   the write proxy used to send messages and other data to
-	 *                     the server
-	 * @since Envoy Client v0.1-beta
-	 */
-	public void initializeData(SceneContext sceneContext, LocalDB localDB, Client client, WriteProxy writeProxy) {
-		this.sceneContext	= sceneContext;
-		this.localDB		= localDB;
-		this.client			= client;
-		this.writeProxy		= writeProxy;
-
-		chats = new FilteredList<>(FXCollections.observableList(localDB.getChats()));
-		chatList.setItems(chats);
-		contactLabel.setText(localDB.getUser().getName());
-		MessageControl.setLocalDB(localDB);
-		MessageControl.setSceneContext(sceneContext);
-
-		if (!client.isOnline()) updateInfoLabel("You are offline", "infoLabel-info");
-
-		recorder = new AudioRecorder();
-		initializeSystemCommandsMap();
-	}
-
 	@Override
 	public void onRestore() { updateRemainingCharsLabel(); }
 
@@ -423,10 +403,7 @@ public final class ChatScene implements Restorable {
 	 * @since Envoy Client v0.1-beta
 	 */
 	@FXML
-	private void settingsButtonClicked() {
+	private void settingsButtonClicked() { sceneContext.load(SceneContext.SceneInfo.SETTINGS_SCENE); }
-		sceneContext.load(SceneContext.SceneInfo.SETTINGS_SCENE);
-		sceneContext.<SettingsScene>getController().initializeData(sceneContext, client);
-	}
 
 	/**
 	 * Actions to perform when the "Add Contact" - Button has been clicked.
@@ -434,15 +411,10 @@ public final class ChatScene implements Restorable {
 	 * @since Envoy Client v0.1-beta
 	 */
 	@FXML
-	private void addContactButtonClicked() {
+	private void addContactButtonClicked() { tabPane.getSelectionModel().select(Tabs.CONTACT_SEARCH.ordinal()); }
-		tabPane.getSelectionModel().select(Tabs.CONTACT_SEARCH);
+
-	}
-	
 	@FXML
-	private void groupCreationButtonClicked() {
+	private void groupCreationButtonClicked() { tabPane.getSelectionModel().select(Tabs.GROUP_CREATION.ordinal()); }
-		eventBus.dispatch(new LoadGroupCreationEvent(localDB));
-		tabPane.getSelectionModel().select(Tabs.GROUP_CREATION);
-	}
 
 	@FXML
 	private void voiceButtonClicked() {

client/src/main/java/envoy/client/ui/controller/GroupCreationTab.java

@@ -4,15 +4,14 @@ import static java.util.function.Predicate.not;
 
 import java.util.stream.Collectors;
 
-import javafx.application.Platform;
 import javafx.fxml.FXML;
 import javafx.scene.control.*;
 import javafx.scene.layout.HBox;
 
 import envoy.client.data.Chat;
+import envoy.client.data.Context;
 import envoy.client.data.LocalDB;
 import envoy.client.event.BackEvent;
-import envoy.client.event.LoadGroupCreationEvent;
 import envoy.client.event.SendEvent;
 import envoy.client.ui.listcell.ContactControl;
 import envoy.client.ui.listcell.ListCellFactory;
@@ -43,7 +42,7 @@ public class GroupCreationTab {
 
 	@FXML
 	private Button createButton;
-	
+
 	@FXML
 	private Button cancelButton;
 
@@ -52,21 +51,22 @@ public class GroupCreationTab {
 
 	@FXML
 	private ListView<User> userList;
-	
+
 	@FXML
 	private Label errorMessageLabel;
-	
+
 	@FXML
 	private Button proceedDupButton;
-	
+
 	@FXML
 	private Button cancelDupButton;
-	
+
 	@FXML
 	private HBox errorProceedBox;
 
-	private LocalDB localDB;
+	private String			name;
-	private String name;
+
+	private final LocalDB	localDB	= Context.getInstance().getLocalDB();
 
 	private static final EventBus eventBus = EventBus.getInstance();
 
@@ -74,20 +74,15 @@ public class GroupCreationTab {
 	private void initialize() {
 		userList.setCellFactory(new ListCellFactory<>(ContactControl::new));
 		userList.getSelectionModel().setSelectionMode(SelectionMode.MULTIPLE);
-		
+		createButton.setDisable(true);
-		eventBus.register(LoadGroupCreationEvent.class, e -> {
+		userList.getItems()
-			createButton.setDisable(true);
+			.addAll(localDB.getChats()
-			this.localDB = e.get();
+				.stream()
-			userList.getItems().clear();
+				.map(Chat::getRecipient)
-			Platform.runLater(() -> userList.getItems()
+				.filter(User.class::isInstance)
-					.addAll(localDB.getChats()
+				.filter(not(localDB.getUser()::equals))
-						.stream()
+				.map(User.class::cast)
-						.map(Chat::getRecipient)
+				.collect(Collectors.toList()));
-						.filter(User.class::isInstance)
-						.filter(not(localDB.getUser()::equals))
-						.map(User.class::cast)
-						.collect(Collectors.toList())));
-		});
 	}
 
 	/**
@@ -96,9 +91,7 @@ public class GroupCreationTab {
 	 * @since Envoy Client v0.1-beta
 	 */
 	@FXML
-	private void userListClicked() {
+	private void userListClicked() { createButton.setDisable(userList.getSelectionModel().isEmpty() || groupNameField.getText().isBlank()); }
-		createButton.setDisable(userList.getSelectionModel().isEmpty() || groupNameField.getText().isBlank());
-	}
 
 	/**
 	 * Checks, whether the {@code createButton} can be enabled because text is
@@ -173,7 +166,7 @@ public class GroupCreationTab {
 		setErrorMessageLabelSize(0);
 		setProcessPaneSize(0);
 	}
-	
+
 	@FXML
 	private void proceedOnNameDuplication() {
 		createButton.setDisable(false);
@@ -184,7 +177,7 @@ public class GroupCreationTab {
 		setProcessPaneSize(0);
 		groupNameField.clear();
 	}
-	
+
 	@FXML
 	private void cancelOnNameDuplication() {
 		createButton.setDisable(false);
@@ -193,13 +186,13 @@ public class GroupCreationTab {
 		setProcessPaneSize(0);
 		groupNameField.clear();
 	}
-	
+
 	private void setErrorMessageLabelSize(int value) {
 		errorMessageLabel.setPrefHeight(value);
 		errorMessageLabel.setMinHeight(value);
 		errorMessageLabel.setMaxHeight(value);
 	}
-	
+
 	private void setProcessPaneSize(int value) {
 		proceedDupButton.setPrefHeight(value);
 		proceedDupButton.setMinHeight(value);

client/src/main/java/envoy/client/ui/controller/LoginScene.java

@@ -1,9 +1,5 @@
 package envoy.client.ui.controller;
 
-import java.io.FileNotFoundException;
-import java.io.IOException;
-import java.time.Instant;
-import java.util.concurrent.TimeoutException;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
@@ -14,16 +10,12 @@ import javafx.scene.control.*;
 import javafx.scene.control.Alert.AlertType;
 import javafx.scene.image.ImageView;
 
-import envoy.client.data.*;
+import envoy.client.data.ClientConfig;
-import envoy.client.net.Client;
+import envoy.client.ui.IconUtil;
-import envoy.client.net.WriteProxy;
+import envoy.client.ui.Startup;
-import envoy.client.ui.*;
 import envoy.data.LoginCredentials;
-import envoy.data.User;
-import envoy.data.User.UserStatus;
 import envoy.event.EventBus;
 import envoy.event.HandshakeRejection;
-import envoy.exception.EnvoyException;
 import envoy.util.Bounds;
 import envoy.util.EnvoyLog;
 
@@ -65,17 +57,11 @@ public final class LoginScene {
 	@FXML
 	private ImageView logo;
 
-	private Client			client;
-	private LocalDB			localDB;
-	private CacheMap		cacheMap;
-	private SceneContext	sceneContext;
-
 	private boolean registration = false;
 
 	private static final Logger			logger		= EnvoyLog.getLogger(LoginScene.class);
 	private static final EventBus		eventBus	= EventBus.getInstance();
 	private static final ClientConfig	config		= ClientConfig.getInstance();
-	private static final Settings		settings	= Settings.getInstance();
 
 	@FXML
 	private void initialize() {
@@ -85,32 +71,9 @@ public final class LoginScene {
 		eventBus.register(HandshakeRejection.class, e -> Platform.runLater(() -> { new Alert(AlertType.ERROR, e.get()).showAndWait(); }));
 
 		logo.setImage(IconUtil.loadIcon("envoy_logo"));
-	}
-
-	/**
-	 * Loads the login dialog using the FXML file {@code LoginDialog.fxml}.
-	 *
-	 * @param client       the client used to perform the handshake
-	 * @param localDB      the local database used for offline login
-	 * @param cacheMap     the map of all caches needed
-	 * @param sceneContext the scene context used to initialize the chat scene
-	 * @since Envoy Client v0.1-beta
-	 */
-	public void initializeData(Client client, LocalDB localDB, CacheMap cacheMap, SceneContext sceneContext) {
-		this.client			= client;
-		this.localDB		= localDB;
-		this.cacheMap		= cacheMap;
-		this.sceneContext	= sceneContext;
-
-		// Prepare handshake
-		localDB.loadIDGenerator();
 
 		// Set initial cursor
 		userTextField.requestFocus();
-
-		// Perform automatic login if configured
-		if (config.hasLoginCredentials())
-			performHandshake(new LoginCredentials(config.getUser(), config.getPassword(), false, Startup.VERSION, loadLastSync(config.getUser())));
 	}
 
 	@FXML
@@ -123,15 +86,12 @@ public final class LoginScene {
 		} else if (!Bounds.isValidContactName(userTextField.getText())) {
 			new Alert(AlertType.ERROR, "The entered user name is not valid (" + Bounds.CONTACT_NAME_PATTERN + ")").showAndWait();
 			userTextField.clear();
-		} else performHandshake(new LoginCredentials(userTextField.getText(), passwordField.getText(), registration,
+		} else Startup.performHandshake(new LoginCredentials(userTextField.getText(), passwordField.getText(), registration, Startup.VERSION,
-				Startup.VERSION, loadLastSync(userTextField.getText())));
+				Startup.loadLastSync(userTextField.getText())));
 	}
 
 	@FXML
-	private void offlineModeButtonPressed() {
+	private void offlineModeButtonPressed() { Startup.attemptOfflineMode(userTextField.getText()); }
-		attemptOfflineMode(new LoginCredentials(userTextField.getText(), passwordField.getText(), false, Startup.VERSION,
-				loadLastSync(userTextField.getText())));
-	}
 
 	@FXML
 	private void registerSwitchPressed() {
@@ -159,102 +119,4 @@ public final class LoginScene {
 		logger.log(Level.INFO, "The login process has been cancelled. Exiting...");
 		System.exit(0);
 	}
-
-	private Instant loadLastSync(String identifier) {
-		try {
-			localDB.loadUsers();
-			localDB.setUser(localDB.getUsers().get(identifier));
-			localDB.initializeUserStorage();
-			localDB.loadUserData();
-		} catch (final Exception e) {
-			// User storage empty, wrong user name etc. -> default lastSync
-		}
-		return localDB.getLastSync();
-	}
-
-	private void performHandshake(LoginCredentials credentials) {
-		try {
-			client.performHandshake(credentials, cacheMap);
-			if (client.isOnline()) {
-				loadChatScene();
-				client.initReceiver(localDB, cacheMap);
-			}
-		} catch (IOException | InterruptedException | TimeoutException e) {
-			logger.log(Level.INFO, "Could not connect to server. Entering offline mode...");
-			attemptOfflineMode(credentials);
-		}
-	}
-
-	private void attemptOfflineMode(LoginCredentials credentials) {
-		try {
-			// Try entering offline mode
-			localDB.loadUsers();
-			final User clientUser = localDB.getUsers().get(credentials.getIdentifier());
-			if (clientUser == null) throw new EnvoyException("Could not enter offline mode: user name unknown");
-			client.setSender(clientUser);
-			loadChatScene();
-		} catch (final Exception e) {
-			new Alert(AlertType.ERROR, "Client error: " + e).showAndWait();
-			logger.log(Level.SEVERE, "Offline mode could not be loaded: ", e);
-			System.exit(1);
-		}
-	}
-
-	private void loadChatScene() {
-
-		// Set client user in local database
-		localDB.setUser(client.getSender());
-
-		// Initialize chats in local database
-		try {
-			localDB.initializeUserStorage();
-			localDB.loadUserData();
-		} catch (final FileNotFoundException e) {
-			// The local database file has not yet been created, probably first login
-		} catch (final Exception e) {
-			new Alert(AlertType.ERROR, "Error while loading local database: " + e + "\nChats will not be stored locally.").showAndWait();
-			logger.log(Level.WARNING, "Could not load local database: ", e);
-		}
-
-		// Initialize write proxy
-		final var writeProxy = new WriteProxy(client, localDB);
-
-		localDB.synchronize();
-
-		if (client.isOnline()) writeProxy.flushCache();
-		else
-			// Set all contacts to offline mode
-			localDB.getChats()
-				.stream()
-				.map(Chat::getRecipient)
-				.filter(User.class::isInstance)
-				.map(User.class::cast)
-				.forEach(u -> u.setStatus(UserStatus.OFFLINE));
-
-		// Load ChatScene
-		sceneContext.pop();
-		sceneContext.getStage().setMinHeight(400);
-		sceneContext.getStage().setMinWidth(843);
-		sceneContext.load(SceneContext.SceneInfo.CHAT_SCENE);
-		sceneContext.<ChatScene>getController().initializeData(sceneContext, localDB, client, writeProxy);
-		sceneContext.getStage().centerOnScreen();
-
-		if (StatusTrayIcon.isSupported()) {
-
-			// Configure hide on close
-			sceneContext.getStage().setOnCloseRequest(e -> {
-				if (settings.isHideOnClose()) {
-					sceneContext.getStage().setIconified(true);
-					e.consume();
-				}
-			});
-
-			// Initialize status tray icon
-			final var trayIcon = new StatusTrayIcon(sceneContext.getStage());
-			settings.getItems().get("hideOnClose").setChangeHandler(c -> {
-				if ((Boolean) c) trayIcon.show();
-				else trayIcon.hide();
-			});
-		}
-	}
 }

client/src/main/java/envoy/client/ui/controller/SettingsScene.java

@@ -5,6 +5,7 @@ import javafx.scene.control.Label;
 import javafx.scene.control.ListView;
 import javafx.scene.control.TitledPane;
 
+import envoy.client.data.Context;
 import envoy.client.net.Client;
 import envoy.client.ui.SceneContext;
 import envoy.client.ui.listcell.AbstractListCell;
@@ -26,21 +27,8 @@ public final class SettingsScene {
 	@FXML
 	private TitledPane titledPane;
 
-	private SceneContext sceneContext;
+	private final Client		client			= Context.getInstance().getClient();
-
+	private final SceneContext	sceneContext	= Context.getInstance().getSceneContext();
-	/**
-	 * @param sceneContext enables the user to return to the chat scene
-	 * @param client       the {@code Client} used to get the current user and to
-	 *                     check if this user is online
-	 * @since Envoy Client v0.1-beta
-	 */
-	public void initializeData(SceneContext sceneContext, Client client) {
-		this.sceneContext = sceneContext;
-		settingsList.getItems().add(new GeneralSettingsPane());
-		settingsList.getItems().add(new UserSettingsPane(sceneContext, client.getSender(), client.isOnline()));
-		settingsList.getItems().add(new DownloadSettingsPane(sceneContext));
-		settingsList.getItems().add(new BugReportPane(client.getSender(), client.isOnline()));
-	}
 
 	@FXML
 	private void initialize() {
@@ -49,6 +37,10 @@ public final class SettingsScene {
 			@Override
 			protected Label renderItem(SettingsPane item) { return new Label(item.getTitle()); }
 		});
+		settingsList.getItems().add(new GeneralSettingsPane());
+		settingsList.getItems().add(new UserSettingsPane(sceneContext, client.getSender(), client.isOnline()));
+		settingsList.getItems().add(new DownloadSettingsPane(sceneContext));
+		settingsList.getItems().add(new BugReportPane(client.getSender(), client.isOnline()));
 	}
 
 	@FXML

client/src/main/java/envoy/client/ui/controller/Tabs.java

@@ -0,0 +1,29 @@
+package envoy.client.ui.controller;
+
+/**
+ * Provides options to select different tabs.
+ * <p>
+ * Project: <strong>client</strong><br>
+ * File: <strong>Tabs.java</strong><br>
+ * Created: <strong>30.8.2020</strong><br>
+ *
+ * @author Maximilian K&auml;fer
+ * @since Envoy Client v0.2-beta
+ */
+public enum Tabs {
+
+	/**
+	 * Selects the {@code contact list} tab.
+	 */
+	CONTACT_LIST,
+
+	/**
+	 * Selects the {@code contact search} tab.
+	 */
+	CONTACT_SEARCH,
+
+	/**
+	 * Selects the {@code group creation} tab.
+	 */
+	GROUP_CREATION;
+}

client/src/main/java/envoy/client/ui/listcell/MessageControl.java

@@ -19,6 +19,7 @@ import javafx.scene.image.ImageView;
 import javafx.scene.layout.*;
 import javafx.stage.FileChooser;
 
+import envoy.client.data.Context;
 import envoy.client.data.LocalDB;
 import envoy.client.data.Settings;
 import envoy.client.ui.AudioControl;
@@ -43,11 +44,10 @@ import envoy.util.EnvoyLog;
  */
 public final class MessageControl extends Label {
 
-	private boolean ownMessage;
+	private final boolean ownMessage;
 
-	private static LocalDB localDB;
+	private final LocalDB		localDB			= Context.getInstance().getLocalDB();
-
+	private final SceneContext	sceneContext	= Context.getInstance().getSceneContext();
-	private static SceneContext sceneContext;
 
 	private static final DateTimeFormatter			dateFormat		= DateTimeFormatter.ofPattern("dd.MM.yyyy HH:mm:ss")
 		.withZone(ZoneId.systemDefault());
@@ -177,22 +177,10 @@ public final class MessageControl extends Label {
 		}
 	}
 
-	/**
-	 * @param localDB the localDB used by the current user
-	 * @since Envoy Client v0.2-beta
-	 */
-	public static void setLocalDB(LocalDB localDB) { MessageControl.localDB = localDB; }
-
 	/**
 	 * @return whether the message stored by this {@code MessageControl} has been
 	 *         sent by this user of Envoy
 	 * @since Envoy Client v0.1-beta
 	 */
 	public boolean isOwnMessage() { return ownMessage; }
-
-	/**
-	 * @param sceneContext the scene context storing the stage used in Envoy
-	 * @since Envoy Client v0.1-beta
-	 */
-	public static void setSceneContext(SceneContext sceneContext) { MessageControl.sceneContext = sceneContext; }
 }

client/src/main/java/envoy/constant/Tabs.java

@@ -1,17 +0,0 @@
-package envoy.constant;
-
-/**
- * Project: <strong>client</strong><br>
- * File: <strong>Tabs.java</strong><br>
- * Created: <strong>Aug 30, 2020</strong><br>
- *
- * @author Maximilian K&auml;fer
- * @since Envoy Client v0.2-beta
- */
-public class Tabs {
-	private Tabs() {}
-	
-	public static int CONTACT_LIST = 0;
-	public static int CONTACT_SEARCH = 1;
-	public static int GROUP_CREATION = 2;
-}