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

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

const BarLevel = imports.ui.barLevel;
const Layout = imports.ui.layout;
const Main = imports.ui.main;

var HIDE_TIMEOUT = 1500;
var FADE_TIME = 100;
var LEVEL_ANIMATION_TIME = 100;

var OsdWindow = GObject.registerClass(
class OsdWindow extends Clutter.Actor {
    _init(monitorIndex) {
        super._init({
            x_expand: true,
            y_expand: true,
            x_align: Clutter.ActorAlign.CENTER,
            y_align: Clutter.ActorAlign.END,
        });

        this._monitorIndex = monitorIndex;
        let constraint = new Layout.MonitorConstraint({ index: monitorIndex });
        this.add_constraint(constraint);

        this._hbox = new St.BoxLayout({
            style_class: 'osd-window',
        });
        this.add_actor(this._hbox);

        this._icon = new St.Icon({ y_expand: true });
        this._hbox.add_child(this._icon);

        this._vbox = new St.BoxLayout({
            vertical: true,
            y_align: Clutter.ActorAlign.CENTER,
        });
        this._hbox.add_child(this._vbox);

        this._label = new St.Label();
        this._vbox.add_child(this._label);

        this._level = new BarLevel.BarLevel({
            style_class: 'level',
            value: 0,
        });
        this._vbox.add_child(this._level);

        this._hideTimeoutId = 0;
        this._reset();
        Main.uiGroup.add_child(this);
    }

    _updateBoxVisibility() {
        this._vbox.visible = [...this._vbox].some(c => c.visible);
    }

    setIcon(icon) {
        this._icon.gicon = icon;
    }

    setLabel(label) {
        this._label.visible = label != undefined;
        if (label)
            this._label.text = label;
        this._updateBoxVisibility();
    }

    setLevel(value) {
        this._level.visible = value != undefined;
        if (value != undefined) {
            if (this.visible) {
                this._level.ease_property('value', value, {
                    mode: Clutter.AnimationMode.EASE_OUT_QUAD,
                    duration: LEVEL_ANIMATION_TIME,
                });
            } else {
                this._level.value = value;
            }
        }
        this._updateBoxVisibility();
    }

    setMaxLevel(maxLevel = 1) {
        this._level.maximum_value = maxLevel;
    }

    show() {
        if (!this._icon.gicon)
            return;

        if (!this.visible) {
            Meta.disable_unredirect_for_display(global.display);
            super.show();
            this.opacity = 0;
            this.get_parent().set_child_above_sibling(this, null);

            this.ease({
                opacity: 255,
                duration: FADE_TIME,
                mode: Clutter.AnimationMode.EASE_OUT_QUAD,
            });
        }

        if (this._hideTimeoutId)
            GLib.source_remove(this._hideTimeoutId);
        this._hideTimeoutId = GLib.timeout_add(
            GLib.PRIORITY_DEFAULT, HIDE_TIMEOUT, this._hide.bind(this));
        GLib.Source.set_name_by_id(this._hideTimeoutId, '[gnome-shell] this._hide');
    }

    cancel() {
        if (!this._hideTimeoutId)
            return;

        GLib.source_remove(this._hideTimeoutId);
        this._hide();
    }

    _hide() {
        this._hideTimeoutId = 0;
        this.ease({
            opacity: 0,
            duration: FADE_TIME,
            mode: Clutter.AnimationMode.EASE_OUT_QUAD,
            onComplete: () => {
                this._reset();
                Meta.enable_unredirect_for_display(global.display);
            },
        });
        return GLib.SOURCE_REMOVE;
    }

    _reset() {
        super.hide();
        this.setLabel(null);
        this.setMaxLevel(null);
        this.setLevel(null);
    }
});

var OsdWindowManager = class {
    constructor() {
        this._osdWindows = [];
        Main.layoutManager.connect('monitors-changed',
                                   this._monitorsChanged.bind(this));
        this._monitorsChanged();
    }

    _monitorsChanged() {
        for (let i = 0; i < Main.layoutManager.monitors.length; i++) {
            if (this._osdWindows[i] == undefined)
                this._osdWindows[i] = new OsdWindow(i);
        }

        for (let i = Main.layoutManager.monitors.length; i < this._osdWindows.length; i++) {
            this._osdWindows[i].destroy();
            this._osdWindows[i] = null;
        }

        this._osdWindows.length = Main.layoutManager.monitors.length;
    }

    _showOsdWindow(monitorIndex, icon, label, level, maxLevel) {
        this._osdWindows[monitorIndex].setIcon(icon);
        this._osdWindows[monitorIndex].setLabel(label);
        this._osdWindows[monitorIndex].setMaxLevel(maxLevel);
        this._osdWindows[monitorIndex].setLevel(level);
        this._osdWindows[monitorIndex].show();
    }

    show(monitorIndex, icon, label, level, maxLevel) {
        if (monitorIndex != -1) {
            for (let i = 0; i < this._osdWindows.length; i++) {
                if (i == monitorIndex)
                    this._showOsdWindow(i, icon, label, level, maxLevel);
                else
                    this._osdWindows[i].cancel();
            }
        } else {
            for (let i = 0; i < this._osdWindows.length; i++)
                this._showOsdWindow(i, icon, label, level, maxLevel);
        }
    }

    hideAll() {
        for (let i = 0; i < this._osdWindows.length; i++)
            this._osdWindows[i].cancel();
    }
};