package envoy.client.ui.settings;

import java.io.*;
import java.nio.file.Files;
import java.util.logging.*;

import javafx.event.EventHandler;
import javafx.geometry.Pos;
import javafx.scene.Cursor;
import javafx.scene.control.*;
import javafx.scene.control.Alert.AlertType;
import javafx.scene.image.*;
import javafx.scene.input.InputEvent;
import javafx.scene.layout.HBox;
import javafx.stage.FileChooser;
import javafx.util.Duration;

import dev.kske.eventbus.core.EventBus;

import envoy.event.*;
import envoy.util.*;

import envoy.client.ui.control.ProfilePicImageView;
import envoy.client.util.*;

/**
 * @author Leon Hofmeister
 * @since Envoy Client v0.2-beta
 */
public final class UserSettingsPane extends OnlineOnlySettingsPane {

	private boolean	profilePicChanged, usernameChanged, validPassword;
	private byte[]	currentImageBytes;
	private String	newUsername, newPassword = "";

	private final ImageView		profilePic				= new ProfilePicImageView(null, 60);
	private final TextField		usernameTextField		= new TextField();
	private final PasswordField	currentPasswordField	= new PasswordField();
	private final PasswordField	newPasswordField		= new PasswordField();
	private final PasswordField	repeatNewPasswordField	= new PasswordField();
	private final Button		saveButton				= new Button("Save");
	private final Button		deleteAccountButton		= new Button("Delete Account (Locally)");

	private static final EventBus	eventBus	= EventBus.getInstance();
	private static final Logger		logger		= EnvoyLog.getLogger(UserSettingsPane.class);

	/**
	 * Creates a new {@code UserSettingsPane}.
	 *
	 * @since Envoy Client v0.2-beta
	 */
	public UserSettingsPane() {
		super("User");
		setSpacing(10);

		// Display of profile pic change mechanism
		final var hbox = new HBox();
		// TODO: display current profile pic
		profilePic.setImage(IconUtil.loadIconThemeSensitive("user_icon"));
		profilePic.setCursor(Cursor.HAND);
		profilePic.setFitWidth(60);
		profilePic.setFitHeight(60);
		profilePic.setOnMouseClicked(e -> {
			if (!client.isOnline())
				return;
			final var pictureChooser = new FileChooser();

			pictureChooser.setTitle("Select a new profile pic");
			pictureChooser.setInitialDirectory(new File(System.getProperty("user.home")));
			pictureChooser.getExtensionFilters().add(
				new FileChooser.ExtensionFilter("Pictures", "*.png", "*.jpg", "*.bmp", "*.gif"));

			final var file = pictureChooser.showOpenDialog(context.getSceneContext().getStage());

			if (file != null) {

				// Check max file size
				// TODO: Move to config
				if (file.length() > 5E6) {
					new Alert(AlertType.WARNING, "The selected file exceeds the size limit of 5MB!")
						.showAndWait();
					return;
				}

				try {
					currentImageBytes = Files.readAllBytes(file.toPath());
					profilePic.setImage(new Image(new ByteArrayInputStream(currentImageBytes)));
					profilePicChanged = true;
				} catch (final IOException e1) {
					e1.printStackTrace();
				}
			}
		});
		hbox.getChildren().add(profilePic);

		// Displaying the username change mechanism
		final var username = client.getSender().getName();
		newUsername = username;
		usernameTextField.setText(username);
		final EventHandler<? super InputEvent> textChanged = e -> {
			newUsername		= usernameTextField.getText();
			usernameChanged	= newUsername != username;
		};
		usernameTextField.setOnInputMethodTextChanged(textChanged);
		usernameTextField.setOnKeyTyped(textChanged);
		hbox.getChildren().add(usernameTextField);
		getChildren().add(hbox);

		// "Displaying" the password change mechanism
		final HBox[]	passwordHBoxes	= { new HBox(), new HBox(), new HBox() };
		final Label[]	passwordLabels	=
			{	new Label("Enter current password:"), new Label("Enter new password:"),
				new Label("Repeat new password:") };

		final PasswordField[]					passwordFields	=
			{ currentPasswordField, newPasswordField, repeatNewPasswordField };
		final EventHandler<? super InputEvent>	passwordEntered	=
			e -> {
																		newPassword	=
																			newPasswordField
																				.getText();
																		validPassword =
																			newPassword.equals(
																				repeatNewPasswordField
																					.getText())
																				&& !newPasswordField
																					.getText()
																					.isBlank();
																	};
		newPasswordField.setOnInputMethodTextChanged(passwordEntered);
		newPasswordField.setOnKeyTyped(passwordEntered);
		repeatNewPasswordField.setOnInputMethodTextChanged(passwordEntered);
		repeatNewPasswordField.setOnKeyTyped(passwordEntered);

		for (int i = 0; i < passwordHBoxes.length; i++) {
			final var hBox2 = passwordHBoxes[i];
			passwordLabels[i].setWrapText(true);
			hBox2.getChildren().add(passwordLabels[i]);
			hBox2.getChildren().add(passwordFields[i]);
			getChildren().add(hBox2);
		}

		// Displaying the save button
		saveButton
			.setOnAction(e -> save(currentPasswordField.getText()));
		saveButton.setAlignment(Pos.BOTTOM_RIGHT);
		getChildren().add(saveButton);

		// Displaying the delete account button
		deleteAccountButton.setAlignment(Pos.BASELINE_CENTER);
		deleteAccountButton.setOnAction(e -> UserUtil.deleteAccount());
		deleteAccountButton.setText("Delete Account (locally)");
		deleteAccountButton.setPrefHeight(25);
		deleteAccountButton.getStyleClass().clear();
		deleteAccountButton.getStyleClass().add("danger-button");
		final var tooltip = new Tooltip("Remote deletion is currently unsupported.");
		tooltip.setShowDelay(Duration.millis(100));
		deleteAccountButton.setTooltip(tooltip);
		getChildren().add(deleteAccountButton);
	}

	/**
	 * Saves the given input and sends the changed input to the server
	 *
	 * @param username the new username
	 * @since Envoy Client v0.2-beta
	 */
	private void save(String oldPassword) {

		// The profile pic was changed
		if (profilePicChanged) {
			final var profilePicChangeEvent = new ProfilePicChange(currentImageBytes);
			eventBus.dispatch(profilePicChangeEvent);
			client.send(profilePicChangeEvent);
			logger.log(Level.INFO, "The user just changed his profile pic.");
		}

		// The username was changed
		final var validContactName = Bounds.isValidContactName(newUsername);
		if (usernameChanged && validContactName) {
			final var nameChangeEvent = new NameChange(client.getSender().getID(), newUsername);
			eventBus.dispatch(nameChangeEvent);
			client.send(nameChangeEvent);
			logger.log(Level.INFO, "The user just changed his name to " + newUsername + ".");
		} else if (!validContactName) {
			final var alert = new Alert(AlertType.ERROR);
			alert.setTitle("Invalid username");
			alert.setContentText(
				"The entered username does not conform with the naming limitations: "
					+ Bounds.CONTACT_NAME_PATTERN);
			alert.showAndWait();
			logger.log(Level.INFO, "An invalid username was requested.");
			return;
		}

		// The password was changed
		if (validPassword) {
			client.send(new PasswordChangeRequest(newPassword, oldPassword));
			logger.log(Level.INFO, "The user just tried to change his password!");
		} else if (!(validPassword || newPassword.isBlank())) {
			final var alert = new Alert(AlertType.ERROR);
			alert.setTitle("Unequal Password");
			alert.setContentText("Repeated password is unequal to the chosen new password");
			alert.showAndWait();
		}
	}
}