/*
 * SPDX-FileCopyrightText: 2019 Mikhail Zolotukhin <zomial@protonmail.com>
 * SPDX-FileCopyrightText: 2019 Nicolas Fella <nicolas.fella@gmx.de>
 *
 * SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
 */

#include <QDBusConnection>
#include <QDBusMessage>
#include <QFont>
#include <QGuiApplication>

#include <KColorScheme>
#include <KPluginFactory>

#include "gtkconfig.h"

K_PLUGIN_CLASS_WITH_JSON(GtkConfig, "gtkconfig.json")

GtkConfig::GtkConfig(QObject *parent, const QVariantList &)
    : KDEDModule(parent)
    , configValueProvider(new ConfigValueProvider())
    , themePreviewer(new ThemePreviewer(this))
    , kdeglobalsConfigWatcher(KConfigWatcher::create(KSharedConfig::openConfig()))
    , kwinConfigWatcher(KConfigWatcher::create(KSharedConfig::openConfig(QStringLiteral("kwinrc"))))
    , kcminputConfigWatcher(KConfigWatcher::create(KSharedConfig::openConfig(QStringLiteral("kcminputrc"))))
    , breezeConfigWatcher(KConfigWatcher::create(KSharedConfig::openConfig(QStringLiteral("breezerc"))))
{
    QDBusConnection dbus = QDBusConnection::sessionBus();
    dbus.registerService(QStringLiteral("org.kde.GtkConfig"));
    dbus.registerObject(QStringLiteral("/GtkConfig"), this, QDBusConnection::ExportScriptableSlots);

    connect(kdeglobalsConfigWatcher.data(), &KConfigWatcher::configChanged, this, &GtkConfig::onKdeglobalsSettingsChange);
    connect(kwinConfigWatcher.data(), &KConfigWatcher::configChanged, this, &GtkConfig::onKWinSettingsChange);
    connect(kcminputConfigWatcher.data(), &KConfigWatcher::configChanged, this, &GtkConfig::onKCMInputSettingsChange);
    connect(breezeConfigWatcher.data(), &KConfigWatcher::configChanged, this, &GtkConfig::onBreezeSettingsChange);

    ConfigEditor::removeLegacyGtk2Strings();
    applyAllSettings();
}

GtkConfig::~GtkConfig()
{
    QDBusConnection dbus = QDBusConnection::sessionBus();
    dbus.unregisterService(QStringLiteral("org.kde.GtkConfig"));
    dbus.unregisterObject(QStringLiteral("/GtkConfig"));
}

void GtkConfig::setGtkTheme(const QString &themeName) const
{
    ConfigEditor::setGtk2ConfigValue(QStringLiteral("gtk-theme-name"), themeName);
    ConfigEditor::setGtkConfigValueGSettings(QStringLiteral("gtk-theme"), themeName);
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-theme-name"), themeName);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-theme-name"), themeName);
    ConfigEditor::setGtk3ConfigValueXSettingsd(QStringLiteral("Net/ThemeName"), themeName);

    // Window decorations are part of the theme, in case of Breeze we inject custom ones from KWin
    setWindowDecorationsAppearance();
}

QString GtkConfig::gtkTheme() const
{
    return ConfigEditor::gtk3ConfigValueSettingsIni(QStringLiteral("gtk-theme-name"));
}

void GtkConfig::showGtkThemePreview(const QString &themeName) const
{
    themePreviewer->showGtk3App(themeName);
}

void GtkConfig::setFont() const
{
    const QString configFontName = configValueProvider->fontName();
    ConfigEditor::setGtk2ConfigValue(QStringLiteral("gtk-font-name"), configFontName);
    ConfigEditor::setGtkConfigValueGSettings(QStringLiteral("font-name"), configFontName);
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-font-name"), configFontName);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-font-name"), configFontName);
    ConfigEditor::setGtk3ConfigValueXSettingsd(QStringLiteral("Gtk/FontName"), configFontName);
}

void GtkConfig::setIconTheme() const
{
    const QString iconThemeName = configValueProvider->iconThemeName();
    ConfigEditor::setGtk2ConfigValue(QStringLiteral("gtk-icon-theme-name"), iconThemeName);
    ConfigEditor::setGtkConfigValueGSettings(QStringLiteral("icon-theme"), iconThemeName);
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-icon-theme-name"), iconThemeName);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-icon-theme-name"), iconThemeName);
    ConfigEditor::setGtk3ConfigValueXSettingsd(QStringLiteral("Net/IconThemeName"), iconThemeName);
}

void GtkConfig::setCursorTheme() const
{
    const QString cursorThemeName = configValueProvider->cursorThemeName();
    ConfigEditor::setGtk2ConfigValue(QStringLiteral("gtk-cursor-theme-name"), cursorThemeName);
    ConfigEditor::setGtkConfigValueGSettings(QStringLiteral("cursor-theme"), cursorThemeName);
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-cursor-theme-name"), cursorThemeName);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-cursor-theme-name"), cursorThemeName);
    ConfigEditor::setGtk3ConfigValueXSettingsd(QStringLiteral("Gtk/CursorThemeName"), cursorThemeName);
}

void GtkConfig::setCursorSize() const
{
    const int cursorSize = configValueProvider->cursorSize();
    ConfigEditor::setGtk2ConfigValue(QStringLiteral("gtk-cursor-theme-size"), cursorSize);
    ConfigEditor::setGtkConfigValueGSettings(QStringLiteral("cursor-size"), cursorSize);
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-cursor-theme-size"), cursorSize);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-cursor-theme-size"), cursorSize);
    ConfigEditor::setGtk3ConfigValueXSettingsd(QStringLiteral("Gtk/CursorThemeSize"), cursorSize);
}

void GtkConfig::setIconsOnButtons() const
{
    const bool iconsOnButtonsConfigValue = configValueProvider->iconsOnButtons();
    ConfigEditor::setGtk2ConfigValue(QStringLiteral("gtk-button-images"), iconsOnButtonsConfigValue);
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-button-images"), iconsOnButtonsConfigValue);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-button-images"), iconsOnButtonsConfigValue);
    ConfigEditor::setGtk3ConfigValueXSettingsd(QStringLiteral("Gtk/ButtonImages"), iconsOnButtonsConfigValue);
}

void GtkConfig::setIconsInMenus() const
{
    const bool iconsInMenusConfigValue = configValueProvider->iconsInMenus();
    ConfigEditor::setGtk2ConfigValue(QStringLiteral("gtk-menu-images"), iconsInMenusConfigValue);
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-menu-images"), iconsInMenusConfigValue);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-menu-images"), iconsInMenusConfigValue);
    ConfigEditor::setGtk3ConfigValueXSettingsd(QStringLiteral("Gtk/MenuImages"), iconsInMenusConfigValue);
}

void GtkConfig::setToolbarStyle() const
{
    const int toolbarStyle = configValueProvider->toolbarStyle();
    ConfigEditor::setGtk2ConfigValue(QStringLiteral("gtk-toolbar-style"), toolbarStyle);
    ConfigEditor::setGtkConfigValueGSettingsAsEnum(QStringLiteral("toolbar-style"), toolbarStyle);
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-toolbar-style"), toolbarStyle);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-toolbar-style"), toolbarStyle);
    ConfigEditor::setGtk3ConfigValueXSettingsd(QStringLiteral("Gtk/ToolbarStyle"), toolbarStyle);
}

void GtkConfig::setScrollbarBehavior() const
{
    const bool scrollbarBehavior = configValueProvider->scrollbarBehavior();
    ConfigEditor::setGtk2ConfigValue(QStringLiteral("gtk-primary-button-warps-slider"), scrollbarBehavior);
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-primary-button-warps-slider"), scrollbarBehavior);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-primary-button-warps-slider"), scrollbarBehavior);
    ConfigEditor::setGtk3ConfigValueXSettingsd(QStringLiteral("Gtk/PrimaryButtonWarpsSlider"), scrollbarBehavior);
}

void GtkConfig::setDarkThemePreference() const
{
    const bool preferDarkTheme = configValueProvider->preferDarkTheme();
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-application-prefer-dark-theme"), preferDarkTheme);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-application-prefer-dark-theme"), preferDarkTheme);
}

void GtkConfig::setWindowDecorationsAppearance() const
{
    if (gtkTheme() == QStringLiteral("Breeze")) { // Only Breeze GTK supports custom decoration buttons
        const auto windowDecorationsButtonsImages = configValueProvider->windowDecorationsButtonsImages();
        ConfigEditor::setCustomClientSideDecorations(windowDecorationsButtonsImages);
    } else {
        ConfigEditor::disableCustomClientSideDecorations();
    }
}

void GtkConfig::setWindowDecorationsButtonsOrder() const
{
    const QString windowDecorationsButtonOrder = configValueProvider->windowDecorationsButtonsOrder();
    ConfigEditor::setGtkConfigValueGSettings(QStringLiteral("button-layout"), windowDecorationsButtonOrder, QStringLiteral("org.gnome.desktop.wm.preferences"));
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-decoration-layout"), windowDecorationsButtonOrder);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-decoration-layout"), windowDecorationsButtonOrder);
    ConfigEditor::setGtk3ConfigValueXSettingsd(QStringLiteral("Gtk/DecorationLayout"), windowDecorationsButtonOrder);
}

void GtkConfig::setEnableAnimations() const
{
    const bool enableAnimations = configValueProvider->enableAnimations();
    ConfigEditor::setGtk2ConfigValue(QStringLiteral("gtk-enable-animations"), enableAnimations);
    ConfigEditor::setGtkConfigValueGSettings(QStringLiteral("enable-animations"), enableAnimations);
    ConfigEditor::setGtk3ConfigValueSettingsIni(QStringLiteral("gtk-enable-animations"), enableAnimations);
    ConfigEditor::setGtk4ConfigValueSettingsIni(QStringLiteral("gtk-enable-animations"), enableAnimations);
    ConfigEditor::setGtk3ConfigValueXSettingsd(QStringLiteral("Gtk/EnableAnimations"), enableAnimations);
}

void GtkConfig::setColors() const
{
    const QMap<QString, QColor> colors = configValueProvider->colors();
    ConfigEditor::setGtk3Colors(colors);
}

void GtkConfig::applyAllSettings() const
{
    setFont();
    setIconTheme();
    setCursorTheme();
    setCursorSize();
    setIconsOnButtons();
    setIconsInMenus();
    setToolbarStyle();
    setScrollbarBehavior();
    setDarkThemePreference();
    setWindowDecorationsAppearance();
    setWindowDecorationsButtonsOrder();
    setEnableAnimations();
    setColors();
}

void GtkConfig::onKdeglobalsSettingsChange(const KConfigGroup &group, const QByteArrayList &names) const
{
    if (group.name() == QStringLiteral("KDE")) {
        if (names.contains(QByteArrayLiteral("AnimationDurationFactor"))) {
            setEnableAnimations();
        }
        if (names.contains(QByteArrayLiteral("ShowIconsInMenuItems"))) {
            setIconsInMenus();
        }
        if (names.contains(QByteArrayLiteral("ShowIconsOnPushButtons"))) {
            setIconsOnButtons();
        }
        if (names.contains(QByteArrayLiteral("ScrollbarLeftClickNavigatesByPage"))) {
            setScrollbarBehavior();
        }
    } else if (group.name() == QStringLiteral("Icons")) {
        if (names.contains(QByteArrayLiteral("Theme"))) {
            setIconTheme();
        }
    } else if (group.name() == QStringLiteral("General")) {
        if (names.contains(QByteArrayLiteral("font"))) {
            setFont();
        }
        if (names.contains(QByteArrayLiteral("ColorScheme")) || names.contains(QByteArrayLiteral("AccentColor"))) {
            setColors();
            setDarkThemePreference();
            setWindowDecorationsAppearance(); // Decorations' color can depend on the current color scheme
        }
    } else if (group.name() == QStringLiteral("Toolbar style")) {
        if (names.contains(QByteArrayLiteral("ToolButtonStyle"))) {
            setToolbarStyle();
        }
    }
}

void GtkConfig::onKWinSettingsChange(const KConfigGroup &group, const QByteArrayList &names) const
{
    if (group.name() == QStringLiteral("org.kde.kdecoration2")) {
        if (names.contains(QByteArrayLiteral("ButtonsOnRight")) //
            || names.contains(QByteArrayLiteral("ButtonsOnLeft"))) {
            setWindowDecorationsButtonsOrder();
        }
        if (names.contains(QByteArrayLiteral("theme"))) {
            setWindowDecorationsAppearance();
        }
    }
}

void GtkConfig::onKCMInputSettingsChange(const KConfigGroup &group, const QByteArrayList &names) const
{
    if (group.name() == QStringLiteral("Mouse")) {
        if (names.contains("cursorTheme")) {
            setCursorTheme();
        }
        if (names.contains("cursorSize")) {
            setCursorSize();
        }
    }
}

void GtkConfig::onBreezeSettingsChange(const KConfigGroup &group, const QByteArrayList &names) const
{
    if (group.name() == QStringLiteral("Common") //
        && names.contains("OutlineCloseButton")) {
        setWindowDecorationsAppearance();
    }
}

#include "gtkconfig.moc"
