// -*- mode: js; js-indent-level: 4; indent-tabs-mode: nil -*-
/* exported WorkspaceSwitcherPopup */

const { Clutter, GLib, GObject, St } = imports.gi;

const Main = imports.ui.main;

var ANIMATION_TIME = 100;
var DISPLAY_TIMEOUT = 600;

var WorkspaceSwitcherPopupList = GObject.registerClass(
class WorkspaceSwitcherPopupList extends St.Widget {
    _init() {
        super._init({
            style_class: 'workspace-switcher',
            offscreen_redirect: Clutter.OffscreenRedirect.ALWAYS,
        });

        this._itemSpacing = 0;
        this._childHeight = 0;
        this._childWidth = 0;
        this._orientation = global.workspace_manager.layout_rows == -1
            ? Clutter.Orientation.VERTICAL
            : Clutter.Orientation.HORIZONTAL;

        this.connect('style-changed', () => {
            this._itemSpacing = this.get_theme_node().get_length('spacing');
        });
    }

    _getPreferredSizeForOrientation(_forSize) {
        let workArea = Main.layoutManager.getWorkAreaForMonitor(Main.layoutManager.primaryIndex);
        let themeNode = this.get_theme_node();

        let availSize;
        if (this._orientation == Clutter.Orientation.HORIZONTAL)
            availSize = workArea.width - themeNode.get_horizontal_padding();
        else
            availSize = workArea.height - themeNode.get_vertical_padding();

        let size = 0;
        for (let child of this.get_children()) {
            let [, childNaturalHeight] = child.get_preferred_height(-1);
            let height = childNaturalHeight * workArea.width / workArea.height;

            if (this._orientation == Clutter.Orientation.HORIZONTAL)
                size += height * workArea.width / workArea.height;
            else
                size += height;
        }

        let workspaceManager = global.workspace_manager;
        let spacing = this._itemSpacing * (workspaceManager.n_workspaces - 1);
        size += spacing;
        size = Math.min(size, availSize);

        if (this._orientation == Clutter.Orientation.HORIZONTAL) {
            this._childWidth = (size - spacing) / workspaceManager.n_workspaces;
            return themeNode.adjust_preferred_width(size, size);
        } else {
            this._childHeight = (size - spacing) / workspaceManager.n_workspaces;
            return themeNode.adjust_preferred_height(size, size);
        }
    }

    _getSizeForOppositeOrientation() {
        let workArea = Main.layoutManager.getWorkAreaForMonitor(Main.layoutManager.primaryIndex);

        if (this._orientation == Clutter.Orientation.HORIZONTAL) {
            this._childHeight = Math.round(this._childWidth * workArea.height / workArea.width);
            return [this._childHeight, this._childHeight];
        } else {
            this._childWidth = Math.round(this._childHeight * workArea.width / workArea.height);
            return [this._childWidth, this._childWidth];
        }
    }

    vfunc_get_preferred_height(forWidth) {
        if (this._orientation == Clutter.Orientation.HORIZONTAL)
            return this._getSizeForOppositeOrientation();
        else
            return this._getPreferredSizeForOrientation(forWidth);
    }

    vfunc_get_preferred_width(forHeight) {
        if (this._orientation == Clutter.Orientation.HORIZONTAL)
            return this._getPreferredSizeForOrientation(forHeight);
        else
            return this._getSizeForOppositeOrientation();
    }

    vfunc_allocate(box) {
        this.set_allocation(box);

        let themeNode = this.get_theme_node();
        box = themeNode.get_content_box(box);

        let childBox = new Clutter.ActorBox();

        let rtl = this.text_direction == Clutter.TextDirection.RTL;
        let x = rtl ? box.x2 - this._childWidth : box.x1;
        let y = box.y1;
        for (let child of this.get_children()) {
            childBox.x1 = Math.round(x);
            childBox.x2 = Math.round(x + this._childWidth);
            childBox.y1 = Math.round(y);
            childBox.y2 = Math.round(y + this._childHeight);

            if (this._orientation == Clutter.Orientation.HORIZONTAL) {
                if (rtl)
                    x -= this._childWidth + this._itemSpacing;
                else
                    x += this._childWidth + this._itemSpacing;
            } else {
                y += this._childHeight + this._itemSpacing;
            }
            child.allocate(childBox);
        }
    }
});

var WorkspaceSwitcherPopup = GObject.registerClass(
class WorkspaceSwitcherPopup extends St.Widget {
    _init() {
        super._init({ x: 0,
                      y: 0,
                      width: global.screen_width,
                      height: global.screen_height,
                      style_class: 'workspace-switcher-group' });

        Main.uiGroup.add_actor(this);

        this._timeoutId = 0;

        this._container = new St.BoxLayout({ style_class: 'workspace-switcher-container' });
        this.add_child(this._container);

        this._list = new WorkspaceSwitcherPopupList();
        this._container.add_child(this._list);

        this._redisplay();

        this.hide();

        let workspaceManager = global.workspace_manager;
        this._workspaceManagerSignals = [];
        this._workspaceManagerSignals.push(workspaceManager.connect('workspace-added',
                                                                    this._redisplay.bind(this)));
        this._workspaceManagerSignals.push(workspaceManager.connect('workspace-removed',
                                                                    this._redisplay.bind(this)));

        this.connect('destroy', this._onDestroy.bind(this));
    }

    _redisplay() {
        let workspaceManager = global.workspace_manager;

        this._list.destroy_all_children();

        for (let i = 0; i < workspaceManager.n_workspaces; i++) {
            const indicator = new St.Bin({
                style_class: 'ws-switcher-indicator',
            });

            if (i === this._activeWorkspaceIndex)
                indicator.add_style_pseudo_class('active');

            this._list.add_actor(indicator);
        }

        let workArea = Main.layoutManager.getWorkAreaForMonitor(Main.layoutManager.primaryIndex);
        let [, containerNatHeight] = this._container.get_preferred_height(global.screen_width);
        let [, containerNatWidth] = this._container.get_preferred_width(containerNatHeight);
        this._container.x = workArea.x + Math.floor((workArea.width - containerNatWidth) / 2);
        this._container.y = workArea.y + Math.floor((workArea.height - containerNatHeight) / 2);
    }

    display(activeWorkspaceIndex) {
        this._activeWorkspaceIndex = activeWorkspaceIndex;

        this._redisplay();
        if (this._timeoutId != 0)
            GLib.source_remove(this._timeoutId);
        this._timeoutId = GLib.timeout_add(GLib.PRIORITY_DEFAULT, DISPLAY_TIMEOUT, this._onTimeout.bind(this));
        GLib.Source.set_name_by_id(this._timeoutId, '[gnome-shell] this._onTimeout');

        const duration = this.visible ? 0 : ANIMATION_TIME;
        this.show();
        this._container.opacity = 0;
        this._container.ease({
            opacity: 255,
            duration,
            mode: Clutter.AnimationMode.EASE_OUT_QUAD,
        });
    }

    _onTimeout() {
        GLib.source_remove(this._timeoutId);
        this._timeoutId = 0;
        this._container.ease({
            opacity: 0.0,
            duration: ANIMATION_TIME,
            mode: Clutter.AnimationMode.EASE_OUT_QUAD,
            onComplete: () => this.destroy(),
        });
        return GLib.SOURCE_REMOVE;
    }

    _onDestroy() {
        if (this._timeoutId)
            GLib.source_remove(this._timeoutId);
        this._timeoutId = 0;

        let workspaceManager = global.workspace_manager;
        for (let i = 0; i < this._workspaceManagerSignals.length; i++)
            workspaceManager.disconnect(this._workspaceManagerSignals[i]);

        this._workspaceManagerSignals = [];
    }
});