mod imp {
    use crate::model::Song;
    use crate::mpv;
    use adw::prelude::*;
    use adw::subclass::prelude::*;
    use glib::subclass::InitializingObject;
    use glib::JoinHandle;
    use gtk::{gdk, gio, glib};
    use std::cell::{Cell, RefCell};
    use std::rc::Rc;
    use tracing::{event, span, Level};

    #[derive(gtk::CompositeTemplate, glib::Properties)]
    #[template(resource = "/eu/callcc/audrey/window.ui")]
    #[properties(wrapper_type = super::Window)]
    pub struct Window {
        #[template_child]
        pub(super) playbar: TemplateChild<crate::ui::Playbar>,

        #[template_child]
        pub(super) play_queue: TemplateChild<crate::ui::PlayQueue>,

        #[property(get, set, default = false)]
        can_click_shuffle_all: Cell<bool>,

        #[property(get, set, nullable)]
        playing_cover_art: RefCell<Option<gdk::Paintable>>,

        #[property(type = Option<Song>, get = Self::song, nullable)]
        _song: (),

        pub(super) setup: crate::ui::Setup,

        pub(super) api: RefCell<Option<Rc<crate::subsonic::Client>>>,

        pub(super) mpv: mpv::Handle,
        #[property(get)]
        playlist_model: gio::ListStore,

        #[property(type = u32, get = Self::volume, set = Self::set_volume)]
        _volume: (),
        #[property(type = bool, get = Self::mute, set = Self::set_mute)]
        _mute: (),
        #[property(type = bool, get = Self::pause, set = Self::set_pause)]
        _pause: (),
        #[property(type = i32, get = Self::playlist_pos)]
        _playlist_pos: (),
        #[property(type = f64, get = Self::time_pos)]
        _time_pos: (),
        #[property(type = f64, get = Self::duration)]
        _duration: (), // as reported by mpv, compare with song.duration
        #[property(type = bool, get = Self::idle_active)]
        _idle_active: (),
        #[property(type = u32, get = Self::playlist_count)]
        _playlist_count: (),

        tick_callback: Cell<Option<gtk::TickCallbackId>>,

        pub(super) queued_seek: Cell<Option<f64>>,

        pub(crate) initial_setup_handle: RefCell<Option<JoinHandle<()>>>,
        mpv_event_loop_handle: RefCell<Option<JoinHandle<()>>>, // really !, not ()
        zbus_executor_loop_handle: RefCell<Option<JoinHandle<()>>>, // same

        loading_cover_handle: RefCell<Option<JoinHandle<()>>>,
    }

    impl Default for Window {
        fn default() -> Self {
            let mpv = mpv::Handle::new();
            mpv.set_property("audio-client-name", "audrey").unwrap();
            mpv.set_property("user-agent", crate::USER_AGENT).unwrap();
            mpv.set_property("vid", false).unwrap();
            mpv.set_property("prefetch-playlist", true).unwrap();

            mpv.observe_property(0, "volume").unwrap();
            mpv.observe_property(1, "mute").unwrap();
            mpv.observe_property(2, "pause").unwrap();
            mpv.observe_property(3, "playlist-pos").unwrap();
            mpv.observe_property(4, "idle-active").unwrap();
            mpv.observe_property(5, "time-pos").unwrap();
            mpv.observe_property(6, "playlist-count").unwrap();
            mpv.observe_property(7, "duration").unwrap();
            mpv.observe_property(8, "path").unwrap();

            // "Useful to drain property changes before a new file is loaded."
            mpv.add_hook(0, "on_before_start_file", 0).unwrap();

            Self {
                playbar: Default::default(),
                play_queue: Default::default(),
                can_click_shuffle_all: Cell::new(false),
                playing_cover_art: Default::default(),
                _song: (),
                setup: Default::default(),
                api: Default::default(),
                mpv,
                playlist_model: gio::ListStore::new::<Song>(),

                _volume: (),
                _mute: (),
                _pause: (),
                _playlist_pos: (),
                _time_pos: (),
                _duration: (),
                _idle_active: (),
                _playlist_count: (),

                tick_callback: Default::default(),

                queued_seek: Default::default(),

                initial_setup_handle: Default::default(),
                mpv_event_loop_handle: Default::default(),
                zbus_executor_loop_handle: Default::default(),

                loading_cover_handle: Default::default(),
            }
        }
    }

    #[glib::object_subclass]
    impl ObjectSubclass for Window {
        const NAME: &'static str = "AudreyUiWindow";
        type Type = super::Window;
        type ParentType = adw::ApplicationWindow;

        fn class_init(klass: &mut Self::Class) {
            klass.bind_template();
            klass.bind_template_callbacks();
        }

        fn instance_init(obj: &InitializingObject<Self>) {
            obj.init_template();
        }
    }

    #[glib::derived_properties]
    impl ObjectImpl for Window {
        fn constructed(&self) {
            self.parent_constructed();

            let window = self.obj().downgrade();
            let mpv_event_loop_handle = glib::spawn_future_local(async move {
                loop {
                    let window = window.upgrade().unwrap();
                    let listener = window.imp().mpv.wakeup_listener();
                    while let Some(event) = window.imp().mpv.wait_event(0.0) {
                        use crate::mpv::Event;

                        match event {
                            Event::PropertyChange(event) => match event.reply_userdata {
                                0 => {
                                    assert_eq!(event.name, "volume");
                                    window.notify("volume");
                                }

                                1 => {
                                    assert_eq!(event.name, "mute");
                                    window.notify("mute");
                                }

                                2 => {
                                    assert_eq!(event.name, "pause");
                                    window.notify("pause");
                                }

                                3 => {
                                    assert_eq!(event.name, "playlist-pos");
                                    window.notify("playlist-pos");
                                }

                                4 => {
                                    assert_eq!(event.name, "idle-active");
                                    window.notify("idle-active");
                                }

                                5 => {
                                    assert_eq!(event.name, "time-pos");
                                    window.notify("time-pos");
                                }

                                6 => {
                                    assert_eq!(event.name, "playlist-count");
                                    window.notify("playlist-count");
                                }

                                7 => {
                                    assert_eq!(event.name, "duration");
                                    window.notify("duration");
                                }

                                8 => {
                                    assert_eq!(event.name, "path");
                                    // sanity check
                                    match window.imp().mpv.get_property::<String>("path") {
                                        Ok(path) => {
                                            assert_eq!(path, window.song().unwrap().stream_url())
                                        }
                                        Err(err) if err.is_property_unavailable() => {}
                                        Err(err) => Err(err).unwrap(),
                                    }
                                }

                                _ => unreachable!(),
                            },

                            Event::StartFile(_) => {
                                event!(Level::INFO, "start file event");
                                window.notify("song");
                                window.imp().buffering_start();

                                let window2 = window.clone();
                                let song_id = window.song().unwrap().id();
                                window
                                    .imp()
                                    .loading_cover_handle
                                    .replace(Some(glib::spawn_future_local(async move {
                                        let api = window2.imp().api.borrow().as_ref().unwrap().clone();
                                        let bytes =
                                            api
                                            .cover_art(&song_id)
                                            .await
                                            .expect("could not load cover art for song {song_id}");

                                        match window2.song() {
                                            Some(song) if song.id() == song_id => {
                                                let texture = gdk::Texture::from_bytes(&glib::Bytes::from_owned(bytes)).expect(
                                                    "could not create texture from cover art for {song_id}",
                                                );
                                                window2.set_playing_cover_art(Some(texture));
                                            }
                                            _ => { event!(Level::WARN, "was too late to fetch cover for song {song_id}") },
                                        }
                                    })))
                                    .map(|handle| handle.abort());
                            }

                            Event::Hook(event) => match event.reply_userdata {
                                0 => {
                                    assert_eq!(&event.name, "on_before_start_file");
                                    event!(Level::DEBUG, "on_before_start_file triggered");
                                    // just use this as a barrier
                                    window.imp().mpv.continue_hook(event.id).unwrap();
                                }

                                _ => unreachable!(),
                            },

                            Event::LogMessage(event) => {
                                let span = span!(Level::DEBUG, "mpv_log", prefix = event.prefix);
                                let _guard = span.enter();
                                match event.log_level {
                                    // level has to be 'static so this sux
                                    l if l <= 20 => {
                                        event!(target: "mpv_event", Level::ERROR, "{}", event.text.trim())
                                    }
                                    l if l <= 30 => {
                                        event!(target: "mpv_event", Level::WARN, "{}", event.text.trim())
                                    }
                                    l if l <= 40 => {
                                        event!(target: "mpv_event", Level::INFO, "{}", event.text.trim())
                                    }
                                    l if l <= 60 => {
                                        event!(target: "mpv_event", Level::DEBUG, "{}", event.text.trim())
                                    }
                                    l if l <= 70 => {
                                        event!(target: "mpv_event", Level::TRACE, "{}", event.text.trim())
                                    }
                                    // should be unused
                                    _ => event!(
                                        target: "mpv_erroneus_event",
                                        Level::DEBUG,
                                        log_level = event.log_level,
                                        "{}",
                                        event.text.trim(),
                                    ),
                                };
                            }

                            Event::Unknown(_) => {
                                // either deprecated or future, ignore
                            }

                            Event::AudioReconfig => {
                                // "This is relatively uninteresting, because there is no such thing as audio output embedding."
                                // ^ ignore
                            }

                            Event::Seek => {
                                event!(Level::INFO, "seek event");
                                window.imp().buffering_start();
                            }

                            Event::PlaybackRestart => {
                                event!(Level::INFO, "playback restart event");
                                window.imp().buffering_end();

                                if let Some(queued_seek) = window.imp().queued_seek.take() {
                                    // a seek was tried before and failed, try again now
                                    event!(Level::INFO, "performing queued seek to {queued_seek}");
                                    window.seek(queued_seek);
                                }
                            }

                            Event::EndFile(event) => {
                                event!(Level::INFO, "end file event: {event:?}");
                                window.notify("song");
                                window.imp().buffering_end();

                                if let Err(err) = event.reason {
                                    event!(Level::ERROR, "end file error: {err}");
                                }

                                // cancel queued seek always
                                window.imp().queued_seek.set(None);

                                window.set_playing_cover_art(None::<gdk::Texture>);
                            }

                            _ => event!(Level::DEBUG, "unhandled {event:?}"),
                        }
                    }
                    drop(window);
                    listener.await;
                }
            });
            self.mpv_event_loop_handle
                .replace(Some(mpv_event_loop_handle));

            // set up mpris
            let window = self.obj().clone();
            let zbus_executor_loop_handle = glib::spawn_future_local(async move {
                let conn = zbus::connection::Builder::session()
                    .expect("could not connect to the session bus")
                    .internal_executor(false)
                    .build()
                    .await
                    .expect("could not build connection to the session bus");

                futures::join!(
                    glib::clone!(
                        #[strong]
                        conn,
                        async move {
                            crate::Mpris::setup(conn.object_server(), &window)
                                .await
                                .expect("could not serve mpris");
                            /*
                            crate::mpris::Player::setup(conn.object_server(), &window.imp().playbin)
                            .await
                            .expect("could not serve mpris player");
                            FIXME */

                            // always set up handlers before requesting service name
                            conn.request_name("org.mpris.MediaPlayer2.audrey")
                                .await
                                .expect("could not register name in session bus");
                        }
                    ),
                    async {
                        loop {
                            conn.executor().tick().await;
                        }
                    }
                );
            });
            self.zbus_executor_loop_handle
                .replace(Some(zbus_executor_loop_handle));
        }
    }

    impl WidgetImpl for Window {}

    impl WindowImpl for Window {}

    impl ApplicationWindowImpl for Window {}

    impl AdwApplicationWindowImpl for Window {}

    #[gtk::template_callbacks]
    impl Window {
        #[template_callback]
        fn show_playbar_cover_art(&self, stack_child: Option<&str>) -> bool {
            stack_child != Some("play-queue")
        }

        #[template_callback]
        async fn shuffle_all(&self) {
            self.obj().set_can_click_shuffle_all(false);

            self.mpv.command(["stop"]).unwrap();
            self.playlist_model.remove_all();
            self.set_pause(false);

            let api = {
                let api = self.api.borrow();
                Rc::clone(api.as_ref().unwrap())
            };
            for song in api.get_random_songs(10).await.unwrap().into_iter() {
                let song = Song::from_child(&api, &song);
                self.mpv
                    .command(["loadfile", &song.stream_url(), "append-play"])
                    .unwrap();
                self.playlist_model.append(&song);
            }
            self.obj().set_can_click_shuffle_all(true);
        }

        #[template_callback]
        fn show_setup_dialog(&self) {
            self.setup.present(Some(self.obj().as_ref()));
        }

        fn volume(&self) -> u32 {
            self.mpv
                .get_property::<i64>("volume")
                .unwrap()
                .try_into()
                .unwrap()
        }

        fn set_volume(&self, volume: u32) {
            self.mpv.set_property("volume", volume as i64).unwrap();
        }

        fn mute(&self) -> bool {
            self.mpv.get_property("mute").unwrap()
        }

        fn set_mute(&self, mute: bool) {
            self.mpv.set_property("mute", mute).unwrap();
        }

        fn pause(&self) -> bool {
            self.mpv.get_property("pause").unwrap()
        }

        fn set_pause(&self, pause: bool) {
            self.mpv.set_property("pause", pause).unwrap();
        }

        fn playlist_pos(&self) -> i32 {
            self.mpv
                .get_property::<i64>("playlist-pos")
                .unwrap()
                .try_into()
                .unwrap()
        }

        fn time_pos(&self) -> f64 {
            if let Some(queued_seek) = self.queued_seek.get() {
                // counterfeit time-pos while the seek is ongoing
                queued_seek
            } else {
                match self.mpv.get_property("time-pos") {
                    Ok(time_pos) => Ok(time_pos),
                    Err(err) if err.is_property_unavailable() => Ok(0.0), //placeholder
                    Err(err) => Err(err),
                }
                .unwrap()
            }
        }

        fn duration(&self) -> f64 {
            let duration = match self.mpv.get_property::<f64>("duration") {
                Ok(duration) => Ok(Some(duration)),
                Err(err) if err.is_property_unavailable() => {
                    Ok(self.song().as_ref().map(|song| song.duration() as f64))
                }
                Err(err) => Err(err),
            }
            .unwrap();

            {
                let left = duration.map(|f| f as i64);
                let right = self.song().as_ref().map(crate::model::Song::duration);
                if left != right {
                    event!(
                        Level::WARN,
                        "mpv duration {left:?} doesn not match subsonic duration {right:?}"
                    );
                }
            }

            duration.unwrap_or(0.0) // placeholder
        }

        fn idle_active(&self) -> bool {
            self.mpv.get_property("idle-active").unwrap()
        }

        fn playlist_count(&self) -> u32 {
            self.mpv
                .get_property::<i64>("playlist-count")
                .unwrap()
                .try_into()
                .unwrap()
        }

        fn song(&self) -> Option<Song> {
            if self.obj().playlist_pos() < 0 {
                None
            } else {
                let song: Song = self
                    .obj()
                    .playlist_model()
                    .item(self.obj().playlist_pos() as u32)
                    .unwrap()
                    .dynamic_cast()
                    .unwrap();

                Some(song)
            }
        }

        fn buffering_start(&self) {
            let started_buffering = std::time::Instant::now();
            self.tick_callback
                .replace(Some(self.obj().add_tick_callback(move |window, _| {
                    // 3 second period from gnome hig
                    if started_buffering.elapsed() > std::time::Duration::from_secs(3) {
                        window.imp().playbar.set_show_pulse_bar(true);
                        window.imp().playbar.pulse_bar().pulse();
                    }
                    glib::ControlFlow::Continue
                })))
                .map(gtk::TickCallbackId::remove);
        }

        fn buffering_end(&self) {
            self.tick_callback.take().map(gtk::TickCallbackId::remove);
            self.playbar.set_show_pulse_bar(false);
        }
    }

    impl Drop for Window {
        fn drop(&mut self) {
            event!(Level::DEBUG, "dropping AudreyUiWindow");

            self.mpv_event_loop_handle.take().unwrap().abort();
            self.zbus_executor_loop_handle.take().unwrap().abort();
        }
    }
}

use adw::prelude::*;
use adw::subclass::prelude::*;
use gtk::{gio, glib};
use std::rc::Rc;
use tracing::{event, Level};

glib::wrapper! {
    pub struct Window(ObjectSubclass<imp::Window>)
        @extends adw::ApplicationWindow, gtk::ApplicationWindow, gtk::Window, gtk::Widget,
        @implements gio::ActionGroup, gio::ActionMap, gtk::Accessible, gtk::Buildable, gtk::ConstraintTarget, gtk::Native, gtk::Root, gtk::ShortcutManager;
}

impl Window {
    pub fn new(app: &impl IsA<gtk::Application>) -> Self {
        let window: Self = glib::Object::builder().property("application", app).build();

        window.imp().setup.set_window(&window);
        let initial_setup_handle = {
            let setup = window.imp().setup.clone();
            glib::spawn_future_local(async move { setup.load().await })
        };
        window
            .imp()
            .initial_setup_handle
            .replace(Some(initial_setup_handle));

        window
    }

    pub fn playbin(&self) -> ! {
        todo!()
    }

    pub fn playlist_play_index(&self, index: Option<i64>) {
        match index.as_ref() {
            Some(index) => self
                .imp()
                .mpv
                .command(["playlist-play-index", &index.to_string()])
                .unwrap(),
            None => self
                .imp()
                .mpv
                .command(["playlist-play-index", "none"])
                .unwrap(),
        };
    }

    pub fn playlist_remove(&self, index: i64) {
        self.imp()
            .mpv
            .command(["playlist-remove", &index.to_string()])
            .unwrap();
        self.playlist_model().remove(index as u32);
    }

    pub fn setup_connected(&self, api: crate::subsonic::Client) {
        self.imp().api.replace(Some(Rc::new(api)));
        self.set_can_click_shuffle_all(true);
    }

    pub fn playlist_next(&self) {
        self.imp().mpv.command(["playlist-next"]).unwrap();
    }

    pub fn playlist_prev(&self) {
        self.imp().mpv.command(["playlist-prev"]).unwrap();
    }

    pub fn seek(&self, new_position: f64) {
        match self
            .imp()
            .mpv
            .command(["seek", &new_position.to_string(), "absolute", "exact"])
        {
            Ok(()) => {}
            Err(err) => {
                event!(Level::INFO, "queuing seek to {new_position}: {err}");
                self.imp().queued_seek.set(Some(new_position));
                self.notify("time-pos");
            }
        }
    }

    pub fn playlist_move(&self, from: u32, to: u32) {
        // NOTE: for mpv, to refers to the "gap" right before i
        // so playlist-move i 0 makes a track the first
        // playlist-move i 1 makes a track the second
        // and playlist-move i playlist-count makes a track the last
        // (so if to is the position of another track, from is left behind to)
        self.imp()
            .mpv
            .command(["playlist-move", &from.to_string(), &to.to_string()])
            .unwrap();

        if from < to {
            // F1234T -> 1234FT
            let mut spliced = Vec::with_capacity((to - from) as usize);
            for i in from + 1..to {
                spliced.push(self.playlist_model().item(i).unwrap());
            }
            spliced.push(self.playlist_model().item(from).unwrap());

            self.playlist_model()
                .splice(from, spliced.len() as u32, &spliced);
        } else if to < from {
            // T1234F -> FT1234
            let mut spliced = Vec::with_capacity((from - to + 1) as usize);
            spliced.push(self.playlist_model().item(from).unwrap());
            spliced.push(self.playlist_model().item(to).unwrap());
            for i in to + 1..from {
                spliced.push(self.playlist_model().item(i).unwrap());
            }

            self.playlist_model()
                .splice(to, spliced.len() as u32, &spliced);
        }
    }
}