@FXML
	void initialize() {
		this.bindToViewModel();
		this.setupChangeListenerListView();
		this.setupChangeListenersForValidation();
		this.setupDisablingOfButtons();
	}

	private void setupDisablingOfButtons() {
		this.addButton.disableProperty().bind(this.firstNameTextField.textProperty().isEmpty().or(this.lastNameTextField
				.textProperty().isEmpty().or(this.phoneNumberTextField.textProperty().isEmpty())));
		this.searchButton.disableProperty().bind(this.phoneNumberTextField.textProperty().isNotEmpty().or(this.viewmodel.contactSelectedProperty()));
	}

	private void setupChangeListenersForValidation() {
		this.phoneNumberTextField.textProperty().addListener((observable, oldValue, newValue) -> {
			if (newValue != null) {
				if (newValue.matches(
						"\\(|\\(\\d{0,3}|\\(\\d{0,3}\\)|\\(\\d{0,3}\\)\\d{0,3}|\\(\\d{0,3}\\)\\d{0,3}\\-|\\(\\d{0,3}\\)\\d{0,3}\\-\\d{0,4}")) {
					this.phoneNumberTextField.setVisible(true);
				} else {
					this.showAlert("Invalid Phone Number", "Required: (XXX)XXX-XXXX");
					this.phoneNumberTextField.setText(oldValue);
				}
			}
		});
		this.phoneNumberTextField.focusedProperty().addListener((observable, oldValue, newValue) -> {
			if (newValue == false
					&& !this.phoneNumberTextField.getText().matches("\\(\\d{0,3}\\)\\d{0,3}\\-\\d{0,4}")) {
				this.showAlert("Invalid Phone Number", "Required: (XXX)XXX-XXXX");
			}
		});
	}

	@FXML
	void handleAdd(ActionEvent event) {
		try {
			if (!this.viewmodel.addContact()) {
				this.showAlert("Add error", "ERROR: contact was not added");
			}
		} catch (IllegalArgumentException | NullPointerException ex) {
			this.showAlert("Add error", "ERROR: couldn't add the contact due to " + ex.getMessage());
		}
	}

	@FXML
	void handleUpdate(ActionEvent event) {
		try {
			if (!this.viewmodel.updateContact()) {
				this.showAlert("Update error", "ERROR: No such a contact");
			}
		} catch (IllegalArgumentException | NullPointerException ex) {
			this.showAlert("Update error", "ERROR: couldn't update the contact due to " + ex.getMessage());
		}
	}

	@FXML
	void handleSearch(ActionEvent event) {
		try {
			if (!this.viewmodel.searchForContact()) {
				this.showAlert("Search error", "ERROR: No such contact");
			}
		} catch (IllegalArgumentException | NullPointerException ex) {
			this.showAlert("Search error", "ERROR: couldn't find the contact due to " + ex.getMessage());
		}
	}

	private void showAlert(String title, String content) {
		Alert alert = new Alert(AlertType.ERROR);
		Window owner = this.guiPane.getScene().getWindow();
		alert.initOwner(owner);
		alert.setTitle(title);
		alert.setContentText(content);
		alert.showAndWait();
	}

	private void setupChangeListenerListView() {
		this.contactsListView.getSelectionModel().selectedItemProperty()
				.addListener((observable, oldcontact, newContact) -> {
					if (newContact != null) {
						this.phoneNumberTextField.setText(newContact.getPhoneNumber());
						this.firstNameTextField.setText(newContact.getFirstName());
						this.lastNameTextField.setText(newContact.getLastName());
					}
				});
	}

	private void bindToViewModel() {
		this.firstNameTextField.textProperty().bindBidirectional(this.viewmodel.firstNameProperty());
		this.lastNameTextField.textProperty().bindBidirectional(this.viewmodel.lastNameProperty());
		this.phoneNumberTextField.textProperty().bindBidirectional(this.viewmodel.phoneNumberProperty());
		this.contactsListView.itemsProperty().bind(this.viewmodel.contactsProperty());
	}
}