package envoy.client;

import java.io.File;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.prefs.Preferences;

import envoy.client.data.Config;
import envoy.client.ui.Color;
import envoy.client.ui.Theme;
import envoy.util.SerializationUtils;

/**
 * Manages all application settings, which are different objects that can be
 * changed during runtime and serialized them by using either the file system or
 * the {@link Preferences} API.<br>
 * <br>
 * Project: <strong>envoy-client</strong><br>
 * File: <strong>Settings.java</strong><br>
 * Created: <strong>11 Nov 2019</strong><br>
 *
 * @author Leon Hofmeister
 * @author Maximilian K&auml;fer
 * @author Kai S. K. Engelbart
 * @since Envoy v0.2-alpha
 */
public class Settings {

	// Actual settings accessible by the rest of the application
	private Map<String, SettingsItem<?>>	items;
	private Map<String, Theme>				themes;

	/**
	 * Settings are stored in this file.
	 */
	private static final File settingsFile = new File(Config.getInstance().getHomeDirectory(), "settings.ser");

	/**
	 * User-defined themes are stored inside this file.
	 */
	private static final File themeFile = new File(Config.getInstance().getHomeDirectory(), "themes.ser");

	/**
	 * Singleton instance of this class.
	 */
	private static Settings settings = new Settings();

	/**
	 * The way to instantiate the settings.
	 * Is set to private to deny other instances of that object.
	 *
	 * @since Envoy v0.2-alpha
	 */
	private Settings() {
		// Load settings from settings file
		try {
			items = SerializationUtils.read(settingsFile, HashMap.class);
		} catch (ClassNotFoundException | IOException e) {
			items = new HashMap<>();
		}
		supplementDefaults();

		// Load themes from theme file
		try {
			themes = SerializationUtils.read(themeFile, HashMap.class);
		} catch (ClassNotFoundException | IOException e1) {
			themes = new HashMap<>();
			setCurrentTheme("dark");
		}

		// Load standard themes not defined in the themes file
		themes.put("dark",
				new Theme("dark", Color.black, Color.darkGray, Color.white, new Color(165, 60, 232), Color.white, Color.orange, Color.blue,
						Color.white, Color.white));
		themes.put("light",
				new Theme("light", new Color(235, 235, 235), Color.white, Color.white, Color.darkGray, Color.black, Color.orange, Color.darkGray,
						Color.black, Color.black));
	}

	/**
	 * This method is used to ensure that there is only one instance of Settings.
	 *
	 * @return the instance of Settings
	 * @since Envoy v0.2-alpha
	 */
	public static Settings getInstance() { return settings; }

	/**
	 * Updates the preferences when the save button is clicked.
	 *
	 * @throws IOException if an error occurs while saving the themes to the theme
	 *                     file
	 * @since Envoy v0.2-alpha
	 */
	public void save() throws IOException {
		// Save settings to settings file
		SerializationUtils.write(settingsFile, items);

		// Save themes to theme file
		SerializationUtils.write(themeFile, themes);
	}

	private void supplementDefaults() {
		items.putIfAbsent("enterToSend", new SettingsItem<>(true, "Enter to send", "Sends a message by pressing the enter key."));
		items.putIfAbsent("onCloseMode", new SettingsItem<>(true, "Hide on close", "Hides the chat window when it is closed."));
		items.putIfAbsent("currentTheme", new SettingsItem<>("dark", null));
	}

	/**
	 * Adds new theme to the theme map.
	 *
	 * @param theme the {@link Theme} to add
	 * @since Envoy v0.2-alpha
	 */
	public void addNewThemeToMap(Theme theme) { settings.getThemes().put(theme.getThemeName(), theme); }

	/**
	 * @return the name of the currently active {@link Theme}
	 * @since Envoy v0.2-alpha
	 */
	public String getCurrentTheme() { return (String) items.get("currentTheme").get(); }

	/**
	 * Sets the name of the current {@link Theme}.
	 *
	 * @param themeName the name to set
	 * @since Envoy v0.2-alpha
	 */
	public void setCurrentTheme(String themeName) { ((SettingsItem<String>) items.get("currentTheme")).set(themeName); }

	/**
	 * @return {@code true}, if pressing the {@code Enter} key suffices to send a
	 *         message. Otherwise it has to be pressed in conjunction with the
	 *         {@code Control} key.
	 * @since Envoy v0.2-alpha
	 */
	public Boolean isEnterToSend() { return (Boolean) items.get("enterToSend").get(); }

	/**
	 * Changes the keystrokes performed by the user to send a message.
	 *
	 * @param enterToSend If set to {@code true} a message can be sent by pressing
	 *                    the {@code Enter} key. Otherwise it has to be pressed in
	 *                    conjunction with the {@code Control} key.
	 * @since Envoy v0.2-alpha
	 */
	public void setEnterToSend(boolean enterToSend) { ((SettingsItem<Boolean>) items.get("enterToSend")).set(enterToSend); }

	/**
	 * @return the current on close mode.
	 * @since Envoy v0.3-alpha
	 */
	public Boolean getCurrentOnCloseMode() { return (Boolean) items.get("onCloseMode").get(); }

	/**
	 * Sets the current on close mode.
	 *
	 * @param currentOnCloseMode the on close mode that should be set.
	 * @since Envoy v0.3-alpha
	 */
	public void setCurrentOnCloseMode(boolean currentOnCloseMode) { ((SettingsItem<Boolean>) items.get("onCloseMode")).set(currentOnCloseMode); }

	/**
	 * @return the items
	 */
	public Map<String, SettingsItem<?>> getItems() { return items; }

	/**
	 * @param items the items to set
	 */
	public void setItems(Map<String, SettingsItem<?>> items) { this.items = items; }

	/**
	 * @return a {@code Map<String, Theme>} of all themes with their names as keys
	 * @since Envoy v0.2-alpha
	 */
	public Map<String, Theme> getThemes() { return themes; }

	/**
	 * Sets the {@code Map<String, Theme>} of all themes with their names as keys
	 *
	 * @param themes the theme map to set
	 * @since Envoy v0.2-alpha
	 */
	public void setThemes(Map<String, Theme> themes) { this.themes = themes; }

	/**
	 * @param themeName the name of the {@link Theme} to get
	 * @return the {@link Theme} with the specified name
	 * @since Envoy v0.3-alpha
	 */
	public Theme getTheme(String themeName) { return themes.get(themeName); }
}