var Extension;
if (imports.misc.extensionUtils.extensions) {
    Extension = imports.misc.extensionUtils.extensions["paperwm@hedning:matrix.org"];
} else {
    Extension = imports.ui.main.extensionManager.lookup("paperwm@hedning:matrix.org");
}

var Clutter = imports.gi.Clutter;
var Meta = imports.gi.Meta;
var AltTab = imports.ui.altTab;
var Main = imports.ui.main;
var Tweener = Extension.imports.utils.tweener;
var Gio = imports.gi.Gio;

var Scratch = Extension.imports.scratch;
var Tiling = Extension.imports.tiling;
var Keybindings = Extension.imports.keybindings;
var utils = Extension.imports.utils;
var debug = utils.debug;

var prefs = Extension.imports.settings.prefs;

var switcherSettings = new Gio.Settings({
    schema_id: 'org.gnome.shell.window-switcher'
})

var LiveAltTab = utils.registerClass(
class LiveAltTab extends AltTab.WindowSwitcherPopup {

    _init(reverse) {
        this.reverse = reverse;
        super._init();
    }

    _getWindowList(reverse) {
        let tabList = global.display.get_tab_list(
            Meta.TabList.NORMAL_ALL,
            switcherSettings.get_boolean('current-workspace-only') ?
                global.workspace_manager.get_active_workspace() : null)
            .filter(w => !Scratch.isScratchWindow(w));

        let scratch = Scratch.getScratchWindows();

        if (Scratch.isScratchWindow(global.display.focus_window)) {
            // Access scratch windows in mru order with shift-super-tab
            return scratch.concat(this.reverse ? tabList.reverse() : tabList);
        } else {
            return tabList.concat(this.reverse ? scratch.reverse() : scratch);
        }
    }

    _initialSelection(backward, actionName) {
        this.space = Tiling.spaces.selectedSpace;
        this.space.startAnimate();

        let monitor = Tiling.spaces.selectedSpace.monitor;
        let workArea = Main.layoutManager.getWorkAreaForMonitor(monitor.index);
        let fog = new Clutter.Actor({x: workArea.x, y: workArea.y,
                                     width: workArea.width, height: workArea.height,
                                     opacity: 0, background_color: Clutter.color_from_string("black")[1]
                                    });

        // this.blur = new Clutter.BlurEffect();
        // this.space.cloneContainer.add_effect(this.blur);
        this.space.setSelectionInactive();

        Main.uiGroup.insert_child_above(fog, global.window_group);
        Tweener.addTween(fog, {
            time: prefs.animation_time,
            opacity: 100,
        });
        this.fog = fog;

        super._initialSelection(backward, actionName);
    }

    _keyPressHandler(keysym, mutterActionId) {
        if (keysym === Clutter.KEY_Escape)
            return Clutter.EVENT_PROPAGATE;
        // After the first super-tab the mutterActionId we get is apparently
        // SWITCH_APPLICATIONS so we need to case on those too.
        switch(mutterActionId) {
        case Meta.KeyBindingAction.SWITCH_APPLICATIONS:
            mutterActionId = Meta.KeyBindingAction.SWITCH_WINDOWS;
            break;
        case Meta.KeyBindingAction.SWITCH_APPLICATIONS_BACKWARD:
            mutterActionId = Meta.KeyBindingAction.SWITCH_WINDOWS_BACKWARD;
            break;
        case Keybindings.idOf('live-alt-tab'):
            mutterActionId = Meta.KeyBindingAction.SWITCH_WINDOWS;
            break;
            ;;
        case Keybindings.idOf('live-alt-tab-backward'):
            mutterActionId = Meta.KeyBindingAction.SWITCH_WINDOWS_BACKWARD;
            break;
            ;;
        }
        // let action = Keybindings.byId(mutterActionId);
        // if (action && action.options.activeInNavigator) {
        //     let space = Tiling.spaces.selectedSpace;
        //     let metaWindow = space.selectedWindow;
        //     action.handler(metaWindow, space);
        //     return true;
        // }
        return super._keyPressHandler(keysym, mutterActionId);
    }

    _select(num) {

        let from = this._switcherList.windows[this._selectedIndex];
        let to = this._switcherList.windows[num];

        this.clone && this.clone.destroy();
        this.clone = null;

        let actor = to.get_compositor_private();
        actor.remove_clip();
        let frame = to.get_frame_rect();
        let clone = new Clutter.Clone({source: actor});
        clone.position = actor.position;

        let space = Tiling.spaces.spaceOfWindow(to);
        if (space.indexOf(to) !== -1) {
            clone.x = Tiling.ensuredX(to, space) + space.monitor.x; 
            clone.x -= frame.x - actor.x;
        }

        this.clone = clone;
        Main.uiGroup.insert_child_above(clone, this.fog);

        // Tiling.ensureViewport(to, space);
        this._selectedIndex = num;
        this._switcherList.highlight(num);
    }

    _finish() {
        this.was_accepted = true;
        super._finish();
    }

    _itemEnteredHandler() {
        // The item-enter (mouse hover) event is triggered even after a item is
        // accepted. This can cause _select to run on the item below the pointer
        // ensuring the wrong window.
        if(!this.was_accepted) {
            super._itemEnteredHandler.apply(this, arguments);
        }
    }

    _onDestroy() {
        super._onDestroy();
        debug('#preview', 'onDestroy', this.was_accepted);
        Tweener.addTween(this.fog, {
            time: prefs.animation_time,
            opacity: 0,
            onStopped: () => {
                this.fog.destroy();
                this.fog = null;
                // this.space.cloneContainer.remove_effect(this.blur);
                this.clone && this.clone.destroy();
                this.clone = null;
                this.space.moveDone();
            }
        });
        let index = this.was_accepted ? this._selectedIndex : 0
        let to = this._switcherList.windows[index];
        Tiling.focus_handler(to);
        let actor = to.get_compositor_private();
        if (this.was_accepted) {
            actor.x = this.clone.x;
            actor.y = this.clone.y;
        }
        actor.set_scale(1, 1);
    }
});

function liveAltTab(meta_window, space, {display, screen, binding}) {
    let tabPopup = new LiveAltTab(binding.is_reversed());
    tabPopup.show(binding.is_reversed(), binding.get_name(), binding.get_mask());
}