package envoy.client.ui.controller;

import java.util.logging.*;

import javafx.application.Platform;
import javafx.fxml.FXML;
import javafx.scene.control.*;
import javafx.scene.control.Alert.AlertType;

import dev.kske.eventbus.core.*;

import envoy.data.User;
import envoy.event.ElementOperation;
import envoy.event.contact.*;
import envoy.util.EnvoyLog;

import envoy.client.data.Context;
import envoy.client.event.BackEvent;
import envoy.client.helper.AlertHelper;
import envoy.client.net.Client;
import envoy.client.ui.control.ContactControl;
import envoy.client.ui.listcell.ListCellFactory;

/**
 * Provides a search bar in which a user name (substring) can be entered. The users with a matching
 * name are then displayed inside a list view. A {@link UserSearchRequest} is sent on every
 * keystroke.
 * <p>
 * <i>The actual search algorithm is implemented on the server.
 * <p>
 * To create a group, a button is available that loads the {@link GroupCreationTab}.
 *
 * @author Leon Hofmeister
 * @author Maximilian K&auml;fer
 * @since Envoy Client v0.1-beta
 */
public class ContactSearchTab {

	@FXML
	private TextArea searchBar;

	@FXML
	private ListView<User> userList;

	private User currentlySelectedUser;

	private final Alert alert = new Alert(AlertType.CONFIRMATION);

	private static final Client		client		= Context.getInstance().getClient();
	private static final EventBus	eventBus	= EventBus.getInstance();
	private static final Logger		logger		= EnvoyLog.getLogger(ChatScene.class);

	@FXML
	private void initialize() {
		eventBus.registerListener(this);
		userList.setCellFactory(new ListCellFactory<>(ContactControl::new));
		alert.setTitle("Add User?");
	}

	@Event
	private void onUserSearchResult(UserSearchResult result) {
		Platform.runLater(() -> {
			userList.getItems().clear();
			userList.getItems().addAll(result.get());
		});
	}

	@Event
	private void onUserOperation(UserOperation operation) {
		final var contact = operation.get();
		if (operation.getOperationType() == ElementOperation.ADD)
			Platform.runLater(() -> {
				userList.getItems().remove(contact);
				if (currentlySelectedUser != null && currentlySelectedUser.equals(contact)
					&& alert.isShowing())
					alert.close();
			});
	}

	/**
	 * If text is present, sends a request to the server.
	 *
	 * @since Envoy Client v0.1-beta
	 */
	@FXML
	private void sendRequest() {
		final var text = searchBar.getText().strip();
		if (!text.isBlank())
			client.send(new UserSearchRequest(text));
		else
			userList.getItems().clear();
	}

	/**
	 * Clears the text in the search bar and the items shown in the list. Additionally disables both
	 * clear and search button.
	 *
	 * @since Envoy Client v0.1-beta
	 */
	@FXML
	private void clear() {
		searchBar.setText(null);
		userList.getItems().clear();
	}

	/**
	 * Sends an {@link UserOperation} for the selected user to the server.
	 *
	 * @since Envoy Client v0.1-beta
	 */
	@FXML
	private void userListClicked() {
		final var user = userList.getSelectionModel().getSelectedItem();
		if (user != null) {
			currentlySelectedUser = user;
			alert.setContentText(
				"Add user " + currentlySelectedUser.getName() + " to your contacts?");
			AlertHelper.confirmAction(alert, this::addAsContact);
		}
	}

	private void addAsContact() {

		// Sends the event to the server
		final var event = new UserOperation(currentlySelectedUser, ElementOperation.ADD);
		client.send(event);

		// Removes the chosen user and updates the UI
		userList.getItems().remove(currentlySelectedUser);
		eventBus.dispatch(event);
		logger.log(Level.INFO, "Added user " + currentlySelectedUser);
	}

	@FXML
	private void backButtonClicked() {
		searchBar.setText("");
		eventBus.dispatch(new BackEvent());
	}
}