import Gio from 'gi://Gio';
import GLib from 'gi://GLib';
import Meta from 'gi://Meta';
import Shell from 'gi://Shell';

import * as Config from '../misc/config.js';
import * as ExtensionDownloader from './extensionDownloader.js';
import * as ExtensionUtils from '../misc/extensionUtils.js';
import * as Main from './main.js';
import * as Screenshot from './screenshot.js';

import {loadInterfaceXML} from '../misc/fileUtils.js';
import {DBusSenderChecker} from '../misc/util.js';
import {ControlsState} from './overviewControls.js';

const GnomeShellIface = loadInterfaceXML('org.gnome.Shell');
const ScreenSaverIface = loadInterfaceXML('org.gnome.ScreenSaver');
const ScreenTimeIface = loadInterfaceXML('org.gnome.Shell.ScreenTime');

export class GnomeShell {
    constructor() {
        this._dbusImpl = Gio.DBusExportedObject.wrapJSObject(GnomeShellIface, this);
        this._dbusImpl.export(Gio.DBus.session, '/org/gnome/Shell');

        this._senderChecker = new DBusSenderChecker([
            'org.gnome.Settings',
            'org.gnome.SettingsDaemon.MediaKeys',
            'org.freedesktop.impl.portal.desktop.gnome',
        ]);

        this._extensionsService = new GnomeShellExtensions();
        this._screenshotService = new Screenshot.ScreenshotService();

        this._grabbedAccelerators = new Map();
        this._grabbers = new Map();

        global.display.connect('accelerator-activated',
            (display, action, device, timestamp) => {
                this._emitAcceleratorActivated(action, device, timestamp);
            });
        global.display.connect('accelerator-deactivated',
            (display, action, device, timestamp) => {
                this._emitAcceleratorDeactivated(action, device, timestamp);
            });

        this._cachedOverviewVisible = false;
        Main.overview.connect('showing',
            this._checkOverviewVisibleChanged.bind(this));
        Main.overview.connect('hidden',
            this._checkOverviewVisibleChanged.bind(this));
    }

    /**
     * This function executes arbitrary code in the main
     * loop, and returns a boolean success and
     * JSON representation of the object as a string.
     *
     * If evaluation completes without throwing an exception,
     * then the return value will be [true, JSON.stringify(result)].
     * If evaluation fails, then the return value will be
     * [false, JSON.stringify(exception)];
     *
     * @async
     * @param {...any} params - method parameters
     * @param {Gio.DBusMethodInvocation} invocation - the invocation
     * @returns {void}
     */
    async EvalAsync(params, invocation) {
        if (!global.context.unsafe_mode) {
            invocation.return_value(new GLib.Variant('(bs)', [false, '']));
            return;
        }

        const [code] = params;
        let returnValue;
        let success;
        try {
            returnValue = JSON.stringify(await eval(code));
            // A hack; DBus doesn't have null/undefined
            if (returnValue === undefined)
                returnValue = '';
            success = true;
        } catch (e) {
            returnValue = `${e}`;
            success = false;
        }
        invocation.return_value(
            new GLib.Variant('(bs)', [success, returnValue]));
    }

    /**
     * Focus the overview's search entry
     *
     * @async
     * @param {...any} params - method parameters
     * @param {Gio.DBusMethodInvocation} invocation - the invocation
     * @returns {void}
     */
    async FocusSearchAsync(params, invocation) {
        try {
            await this._senderChecker.checkInvocation(invocation);
        } catch (e) {
            invocation.return_gerror(e);
            return;
        }

        Main.overview.focusSearch();
        invocation.return_value(null);
    }

    /**
     * Show OSD with the specified parameters
     *
     * @async
     * @param {...any} params - method parameters
     * @param {Gio.DBusMethodInvocation} invocation - the invocation
     * @returns {void}
     */
    async ShowOSDAsync([params], invocation) {
        try {
            await this._senderChecker.checkInvocation(invocation);
        } catch (e) {
            invocation.return_gerror(e);
            return;
        }

        for (let param in params)
            params[param] = params[param].deepUnpack();

        const {
            connector,
            label,
            level,
            max_level: maxLevel,
            icon: serializedIcon,
        } = params;

        let monitorIndex = -1;
        if (connector) {
            const monitorManager = global.backend.get_monitor_manager();
            monitorIndex = monitorManager.get_monitor_for_connector(connector);
        }

        let icon = null;
        if (serializedIcon)
            icon = Gio.Icon.new_for_string(serializedIcon);

        Main.osdWindowManager.show(monitorIndex, icon, label, level, maxLevel);
        invocation.return_value(null);
    }

    /**
     * Focus specified app in the overview's app grid
     *
     * @async
     * @param {string} id - an application ID
     * @param {Gio.DBusMethodInvocation} invocation - the invocation
     * @returns {void}
     */
    async FocusAppAsync([id], invocation) {
        try {
            await this._senderChecker.checkInvocation(invocation);
        } catch (e) {
            invocation.return_gerror(e);
            return;
        }

        const appSys = Shell.AppSystem.get_default();
        if (appSys.lookup_app(id) === null) {
            invocation.return_error_literal(
                Gio.DBusError,
                Gio.DBusError.FILE_NOT_FOUND,
                `No app with ID ${id}`);
            return;
        }

        Main.overview.selectApp(id);
        invocation.return_value(null);
    }

    /**
     * Show the overview's app grid
     *
     * @async
     * @param {...any} params - method parameters
     * @param {Gio.DBusMethodInvocation} invocation - the invocation
     * @returns {void}
     */
    async ShowApplicationsAsync(params, invocation) {
        try {
            await this._senderChecker.checkInvocation(invocation);
        } catch (e) {
            invocation.return_gerror(e);
            return;
        }

        Main.overview.show(ControlsState.APP_GRID);
        invocation.return_value(null);
    }

    async GrabAcceleratorAsync(params, invocation) {
        try {
            await this._senderChecker.checkInvocation(invocation);
        } catch (e) {
            invocation.return_gerror(e);
            return;
        }

        let [accel, modeFlags, grabFlags] = params;
        let sender = invocation.get_sender();
        let bindingAction = this._grabAcceleratorForSender(accel, modeFlags, grabFlags, sender);
        invocation.return_value(GLib.Variant.new('(u)', [bindingAction]));
    }

    async GrabAcceleratorsAsync(params, invocation) {
        try {
            await this._senderChecker.checkInvocation(invocation);
        } catch (e) {
            invocation.return_gerror(e);
            return;
        }

        let [accels] = params;
        let sender = invocation.get_sender();
        let bindingActions = [];
        for (let i = 0; i < accels.length; i++) {
            let [accel, modeFlags, grabFlags] = accels[i];
            bindingActions.push(this._grabAcceleratorForSender(accel, modeFlags, grabFlags, sender));
        }
        invocation.return_value(GLib.Variant.new('(au)', [bindingActions]));
    }

    async UngrabAcceleratorAsync(params, invocation) {
        try {
            await this._senderChecker.checkInvocation(invocation);
        } catch (e) {
            invocation.return_gerror(e);
            return;
        }

        let [action] = params;
        let sender = invocation.get_sender();
        let ungrabSucceeded = this._ungrabAcceleratorForSender(action, sender);

        invocation.return_value(GLib.Variant.new('(b)', [ungrabSucceeded]));
    }

    async UngrabAcceleratorsAsync(params, invocation) {
        try {
            await this._senderChecker.checkInvocation(invocation);
        } catch (e) {
            invocation.return_gerror(e);
            return;
        }

        let [actions] = params;
        let sender = invocation.get_sender();
        let ungrabSucceeded = true;

        for (let i = 0; i < actions.length; i++)
            ungrabSucceeded &= this._ungrabAcceleratorForSender(actions[i], sender);

        invocation.return_value(GLib.Variant.new('(b)', [ungrabSucceeded]));
    }

    async ScreenTransitionAsync(params, invocation) {
        try {
            await this._senderChecker.checkInvocation(invocation);
        } catch (e) {
            invocation.return_gerror(e);
            return;
        }

        Main.layoutManager.screenTransition.run();

        invocation.return_value(null);
    }

    _emitAcceleratorSignal(signal, action, device, timestamp) {
        let destination = this._grabbedAccelerators.get(action);
        if (!destination)
            return;

        let connection = this._dbusImpl.get_connection();
        let info = this._dbusImpl.get_info();
        let params = {
            'timestamp': GLib.Variant.new('u', timestamp),
            'action-mode': GLib.Variant.new('u', Main.actionMode),
        };

        let deviceNode = device.get_device_node();
        if (deviceNode)
            params['device-node'] = GLib.Variant.new('s', deviceNode);

        connection.emit_signal(
            destination,
            this._dbusImpl.get_object_path(),
            info?.name ?? null,
            signal,
            GLib.Variant.new('(ua{sv})', [action, params]));
    }

    _emitAcceleratorActivated(action, device, timestamp) {
        this._emitAcceleratorSignal(
            'AcceleratorActivated', action, device, timestamp);
    }

    _emitAcceleratorDeactivated(action, device, timestamp) {
        this._emitAcceleratorSignal(
            'AcceleratorDeactivated', action, device, timestamp);
    }

    _grabAcceleratorForSender(accelerator, modeFlags, grabFlags, sender) {
        let bindingAction = global.display.grab_accelerator(accelerator, grabFlags);
        if (bindingAction === Meta.KeyBindingAction.NONE)
            return Meta.KeyBindingAction.NONE;

        let bindingName = Meta.external_binding_name_for_action(bindingAction);
        Main.wm.allowKeybinding(bindingName, modeFlags);

        this._grabbedAccelerators.set(bindingAction, sender);

        if (!this._grabbers.has(sender)) {
            let id = Gio.bus_watch_name(Gio.BusType.SESSION,
                sender, 0, null, this._onGrabberBusNameVanished.bind(this));
            this._grabbers.set(sender, id);
        }

        return bindingAction;
    }

    _ungrabAccelerator(action) {
        let ungrabSucceeded = global.display.ungrab_accelerator(action);
        if (ungrabSucceeded)
            this._grabbedAccelerators.delete(action);

        return ungrabSucceeded;
    }

    _ungrabAcceleratorForSender(action, sender) {
        let grabbedBy = this._grabbedAccelerators.get(action);
        if (sender !== grabbedBy)
            return false;

        return this._ungrabAccelerator(action);
    }

    _onGrabberBusNameVanished(connection, name) {
        let grabs = this._grabbedAccelerators.entries();
        for (let [action, sender] of grabs) {
            if (sender === name)
                this._ungrabAccelerator(action);
        }
        Gio.bus_unwatch_name(this._grabbers.get(name));
        this._grabbers.delete(name);
    }

    async ShowMonitorLabelsAsync(params, invocation) {
        try {
            await this._senderChecker.checkInvocation(invocation);
        } catch (e) {
            invocation.return_gerror(e);
            return;
        }

        let sender = invocation.get_sender();
        let [dict] = params;
        Main.osdMonitorLabeler.show(sender, dict);
        invocation.return_value(null);
    }

    async HideMonitorLabelsAsync(params, invocation) {
        try {
            await this._senderChecker.checkInvocation(invocation);
        } catch (e) {
            invocation.return_gerror(e);
            return;
        }

        let sender = invocation.get_sender();
        Main.osdMonitorLabeler.hide(sender);
        invocation.return_value(null);
    }

    _checkOverviewVisibleChanged() {
        if (Main.overview.visible !== this._cachedOverviewVisible) {
            this._cachedOverviewVisible = Main.overview.visible;
            this._dbusImpl.emit_property_changed('OverviewActive', new GLib.Variant('b', this._cachedOverviewVisible));
        }
    }

    get Mode() {
        return global.session_mode;
    }

    get OverviewActive() {
        return this._cachedOverviewVisible;
    }

    set OverviewActive(visible) {
        if (visible)
            Main.overview.show();
        else
            Main.overview.hide();
    }

    get ShellVersion() {
        return Config.PACKAGE_VERSION;
    }
}

const GnomeShellExtensionsIface = loadInterfaceXML('org.gnome.Shell.Extensions');

class GnomeShellExtensions {
    constructor() {
        this._dbusImpl = Gio.DBusExportedObject.wrapJSObject(GnomeShellExtensionsIface, this);
        this._dbusImpl.export(Gio.DBus.session, '/org/gnome/Shell');

        this._userExtensionsEnabled = this.UserExtensionsEnabled;
        global.settings.connect('changed::disable-user-extensions', () => {
            if (this._userExtensionsEnabled === this.UserExtensionsEnabled)
                return;

            this._userExtensionsEnabled = this.UserExtensionsEnabled;
            this._dbusImpl.emit_property_changed('UserExtensionsEnabled',
                new GLib.Variant('b', this._userExtensionsEnabled));
        });

        Main.extensionManager.connect('extension-state-changed',
            this._extensionStateChanged.bind(this));
    }

    ListExtensions() {
        let out = {};
        Main.extensionManager.getUuids().forEach(uuid => {
            let dbusObj = this.GetExtensionInfo(uuid);
            out[uuid] = dbusObj;
        });
        return out;
    }

    GetExtensionInfo(uuid) {
        let extension = Main.extensionManager.lookup(uuid) || {};
        return ExtensionUtils.serializeExtension(extension);
    }

    GetExtensionErrors(uuid) {
        let extension = Main.extensionManager.lookup(uuid);
        if (!extension)
            return [];

        if (!extension.errors)
            return [];

        return extension.errors;
    }

    InstallRemoteExtensionAsync([uuid], invocation) {
        return ExtensionDownloader.installExtension(uuid, invocation);
    }

    UninstallExtension(uuid) {
        return ExtensionDownloader.uninstallExtension(uuid);
    }

    EnableExtension(uuid) {
        return Main.extensionManager.enableExtension(uuid);
    }

    DisableExtension(uuid) {
        return Main.extensionManager.disableExtension(uuid);
    }

    LaunchExtensionPrefs(uuid) {
        this.OpenExtensionPrefs(uuid, '', {});
    }

    OpenExtensionPrefs(uuid, parentWindow, options) {
        Main.extensionManager.openExtensionPrefs(uuid, parentWindow, options);
    }

    ReloadExtensionAsync(params, invocation) {
        invocation.return_error_literal(
            Gio.DBusError,
            Gio.DBusError.NOT_SUPPORTED,
            'ReloadExtension is deprecated and does not work');
    }

    CheckForUpdates() {
        ExtensionDownloader.checkForUpdates();
    }

    get ShellVersion() {
        return Config.PACKAGE_VERSION;
    }

    get UserExtensionsEnabled() {
        return !global.settings.get_boolean('disable-user-extensions');
    }

    set UserExtensionsEnabled(enable) {
        global.settings.set_boolean('disable-user-extensions', !enable);
    }

    _extensionStateChanged(_, newState) {
        let state = ExtensionUtils.serializeExtension(newState);
        this._dbusImpl.emit_signal('ExtensionStateChanged',
            new GLib.Variant('(sa{sv})', [newState.uuid, state]));

        this._dbusImpl.emit_signal('ExtensionStatusChanged',
            new GLib.Variant('(sis)', [newState.uuid, newState.state, newState.error]));
    }
}

export class ScreenSaverDBus {
    constructor(screenShield) {
        this._screenShield = screenShield;
        screenShield.connect('active-changed', shield => {
            this._dbusImpl.emit_signal('ActiveChanged', GLib.Variant.new('(b)', [shield.active]));
        });
        screenShield.connect('wake-up-screen', () => {
            this._dbusImpl.emit_signal('WakeUpScreen', null);
        });

        this._dbusImpl = Gio.DBusExportedObject.wrapJSObject(ScreenSaverIface, this);
        this._dbusImpl.export(Gio.DBus.session, '/org/gnome/ScreenSaver');

        Gio.DBus.session.own_name('org.gnome.Shell.ScreenShield',
            Gio.BusNameOwnerFlags.NONE, null, null);
    }

    LockAsync(parameters, invocation) {
        let tmpId = this._screenShield.connect('lock-screen-shown', () => {
            this._screenShield.disconnect(tmpId);

            invocation.return_value(null);
        });

        this._screenShield.lock(true);
    }

    SetActive(active) {
        if (active)
            this._screenShield.activate(true);
        else
            this._screenShield.deactivate(false);
    }

    GetActive() {
        return this._screenShield.active;
    }

    GetActiveTime() {
        let started = this._screenShield.activationTime;
        if (started > 0)
            return Math.floor((GLib.get_monotonic_time() - started) / 1000000);
        else
            return 0;
    }
}

export class ScreenTimeDBus {
    constructor(breakManager) {
        this._manager = breakManager;

        this._manager.connect('notify::state', this._onNotify.bind(this));
        this._manager.connect('notify::last-break-end-time', this._onNotify.bind(this));

        this._dbusImpl = Gio.DBusExportedObject.wrapJSObject(ScreenTimeIface, this);
        this._dbusImpl.export(Gio.DBus.session, '/org/gnome/Shell/ScreenTime');
    }

    _onNotify() {
        // We always want to notify the two properties together, as clients need
        // both values to be useful. GJS will combine the two emissions for us.
        this._dbusImpl.emit_property_changed('State', new GLib.Variant('u', this.State));
        this._dbusImpl.emit_property_changed('LastBreakEndTime', new GLib.Variant('t', this.LastBreakEndTime));
    }

    get State() {
        return this._manager.state;
    }

    get LastBreakEndTime() {
        return this._manager.lastBreakEndTime;
    }
}
