/**
 * @author Tres Finocchiaro
 *
 * Copyright (C) 2016 Tres Finocchiaro, QZ Industries, LLC
 *
 * LGPL 2.1 This is free software.  This software and source code are released under
 * the "LGPL 2.1 License".  A copy of this license should be distributed with
 * this software. http://www.gnu.org/licenses/lgpl-2.1.html
 */

package qz.utils;

import com.github.zafarkhaja.semver.Version;
import qz.common.Constants;
import qz.ui.component.IconCache;

import java.awt.*;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Pattern;

/**
 * Utility class for Ubuntu OS specific functions.
 *
 * @author Tres Finocchiaro
 */
public class UbuntuUtilities {

    static Color trayColor;


    /**
     * Attempts to get the SystemTray background color from the Ubuntu OS by
     * first parsing the theme name registered with GTK, and then parsing the
     * {@code dark_bg_color} value from the GTK stylesheet.
     *
     * @return The Ubuntu system tray background color, or <code>Color.WHITE</code> if it cannot be determined
     */
    public static Color getTrayColor() {
        if (trayColor == null) {
            trayColor = ColorUtilities.DEFAULT_COLOR;

            // Ubuntu 12.04 LTS
            String themeName = getThemeName("Ambiance");
            String stdout = ShellUtilities.execute(
                    new String[] {
                            "grep", "dark_bg_color",
                            "/usr/share/themes/" + themeName + "/gtk-3.0/gtk.css"
                    },
                    new String[] {
                            "dark_bg_color"
                    });
            if (stdout.isEmpty()) {
                // Ubuntu 14.04 LTS
                stdout = ShellUtilities.execute(
                        // Ubuntu 12.04 - 14.04
                        new String[] {
                                "grep", "dark_bg_color",
                                "/usr/share/themes/" + themeName + "/gtk-3.0/gtk-main.css"
                        },
                        new String[] {
                                "dark_bg_color"
                        });
            }
            if (!stdout.isEmpty() && stdout.contains("#")) {
                String[] split = stdout.split("#");
                if (split.length == 2) {
                    trayColor = ColorUtilities.decodeHtmlColorString(split[1]);
                }
            }
        }

        return trayColor;
    }

    /**
     * Attempts to retrieve the Ubuntu theme name, i.e. "Ambiance", "Radiance", etc
     *
     * @return the current running theme, or an empty String if it could not be determined.
     */
    public static String getThemeName(String defaultTheme) {
        String themeName = "";
        if(ShellUtilities.execute("which", "gconftool-2")) {
            themeName = ShellUtilities.execute(
                    new String[] {
                            "gconftool-2",
                            "--get",
                            "/desktop/gnome/shell/windows/theme"
                    },
                    null
            );
        }

        return themeName.isEmpty()? defaultTheme:themeName;
    }

    /**
     * Replaces the cached tray icons with Ubuntu colorized ones,
     * fixing a Java bug which gives them undesirable transparency
     *
     * @param iconCache The icons which have been cached
     */
    public static void fixTrayIcons(IconCache iconCache) {
        // Execute some shell commands to determine specific Linux OS
        if (SystemUtilities.isUbuntu()) {
            for(IconCache.Icon i : IconCache.getTypes()) {
                if (i.isTrayIcon()) {
                    iconCache.setBgColor(i, getTrayColor());
                }
            }
        }
    }

    /**
     * Runs a shell command to determine if "Dark" desktop theme is enabled
     * @return true if enabled, false if not
     */
    public static boolean isDarkMode() {
        return !ShellUtilities.execute(new String[] { "gsettings", "get", "org.gnome.desktop.interface", "gtk-theme" }, new String[] { "dark" }, true, true).isEmpty();
    }

    public static double getScaleFactor() {
        if (Constants.JAVA_VERSION.lessThan(Version.valueOf("11.0.0"))) {
            return Toolkit.getDefaultToolkit().getScreenResolution() / 96.0;
        }
        return GtkUtilities.getScaleFactor();
    }
}