// ▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄
//██Let me play the world's tiniest piano for you. ██
//█▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀█
//█▙▙█▙▙▙█▙▙█▙▙▙█▙▙█▙▙▙█▙▙█▙▙▙█▙▙█▙▙▙█▙▙█▙▙▙█▙▙█▙▙▙██
//█▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄█
//███████████████████████████████████████████████████
//█                      ▀ ▀ ▀                      █
#![allow(unused, clippy::unit_arg)]
#![feature(adt_const_params, associated_type_defaults, if_let_guard, impl_trait_in_assoc_type,
    type_alias_impl_trait, trait_alias, type_changing_struct_update, closure_lifetime_binder)]
pub use ::{
    tek_engine::*,
    tek_device,
    tek_device::*,
    tengri::{
        Usually, Perhaps, Has, MaybeHas, has, maybe_has,
        dsl::*, input::*, output::*, tui::*,
        tui::ratatui,
        tui::ratatui::prelude::buffer::Cell,
        tui::ratatui::prelude::Color::{self, *},
        tui::ratatui::prelude::{Style, Stylize, Buffer, Modifier},
        tui::crossterm,
        tui::crossterm::event::{Event, KeyCode::{self, *}},
    },
    std::{
        path::{Path, PathBuf},
        sync::{Arc, RwLock},
        sync::atomic::{AtomicBool, AtomicUsize, Ordering::Relaxed},
        error::Error,
        collections::BTreeMap,
        fmt::Write,
    },
    xdg::BaseDirectories,
};
mod app_jack; pub use self::app_jack::*;
#[cfg(test)] mod app_test;
/// Total state
#[derive(Default, Debug)]
pub struct App {
    /// Must not be dropped for the duration of the process
    pub jack:    Jack<'static>,
    /// Display size
    pub size:    Measure<TuiOut>,
    /// Performance counter
    pub perf:    PerfModel,
    /// Available view modes and input bindings
    pub config:  Config,
    /// Currently selected mode
    pub mode:    Mode<Arc<str>>,
    /// Contains the currently edited musical arrangement
    pub project: Arrangement,
    /// Contains all recently created clips.
    pub pool:    Pool,
    /// Undo history
    pub history: Vec<(AppCommand, Option<AppCommand>)>,
    /// Dialog overlay
    pub dialog:  Dialog,
    /// Base color.
    pub color:   ItemTheme,
}
/// Configuration
#[derive(Default, Debug)]
pub struct Config {
    pub dirs:  BaseDirectories,
    pub modes: Arc<RwLock<BTreeMap<Arc<str>, Arc<Mode<Arc<str>>>>>>,
    pub binds: Arc<RwLock<BTreeMap<Arc<str>, EventMap<Option<TuiEvent>, Arc<str>>>>>,
}
#[derive(Default, Debug)]
pub struct Mode<D: Dsl + Ord> {
    pub path:  PathBuf,
    pub name:  Vec<D>,
    pub info:  Vec<D>,
    pub view:  Vec<D>,
    pub keys:  Vec<D>,
    pub modes: BTreeMap<D, Mode<D>>,
}
/// Various possible dialog modes.
#[derive(Debug, Clone, Default)]
pub enum Dialog {
    #[default] None,
    Help(usize),
    Menu(usize),
    Device(usize),
    Message(Arc<str>),
    Browser(BrowserTarget, Arc<Browser>),
    Options,
}
impl Config {
    const CONFIG: &'static str = "tek.edn";
    const DEFAULTS: &'static str = include_str!("../../tek.edn");
    pub fn init () -> Usually<Self> {
        let mut cfgs: Self = Default::default();
        cfgs.dirs = BaseDirectories::with_profile("tek", "v0");
        cfgs.init_file(Self::CONFIG, Self::DEFAULTS, |cfgs, dsl|cfgs.load_defs(dsl))?;
        Ok(cfgs)
    }
    pub fn init_file (
        &mut self, path: &str, defaults: &str, mut each: impl FnMut(&mut Self, &str)->Usually<()>
    ) -> Usually<()> {
        if self.dirs.find_config_file(path).is_none() {
            println!("Creating {path:?}");
            std::fs::write(self.dirs.place_config_file(path)?, defaults);
        }
        Ok(if let Some(path) = self.dirs.find_config_file(path) {
            println!("Loading {path:?}");
            let src = std::fs::read_to_string(&path)?;
            src.as_str().each(move|item|each(self, item))?;
        } else {
            return Err(format!("{path}: not found").into())
        })
    }
    pub fn load_defs (&mut self, dsl: impl Dsl) -> Usually<()> {
        dsl.each(|item|{
            println!("{item:?} {:?}", item.expr().head());
            match item.expr().head() {
                Ok(Some("keys")) if let Some(id) = item.expr().tail().head()? =>
                    self.load_bind(id.into(), item),
                Ok(Some("mode")) if let Some(id) = item.expr().tail().head()? =>
                    self.load_mode(id.into(), item),
                _ => return Err(format!("load_defs: unexpected: {item:?}").into())
            }
        })
    }
    pub fn load_bind (&mut self, id: Arc<str>, item: impl Dsl) -> Usually<()> {
        let mut map = EventMap::new();
        item.expr().tail().tail()?.each(|item|if item.expr().head() == Ok(Some("see")) {
            // TODO
            Ok(())
        } else if let Ok(Some(word)) = item.expr().head().word() {
            map.add(TuiEvent::from_dsl(item.expr()?.head()?)?, Binding {
                commands:    [item.expr()?.tail()?.unwrap_or_default().into()].into(),
                condition:   None,
                description: None,
                source:      None
            });
            Ok(())
        } else {
            return Err(format!("load_bind: unexpected: {item:?}").into())
        })?;
        self.binds.write().unwrap().insert(id, map);
        Ok(())
    }
    pub fn load_mode (&mut self, id: Arc<str>, item: impl Dsl) -> Usually<()> {
        let mut mode = Mode::default();
        item.expr().tail().tail()?.each(|item|Self::load_mode_one(&mut mode, item))?;
        self.modes.write().unwrap().insert(id.into(), Arc::new(mode));
        Ok(())
    }
    pub fn load_mode_one (mode: &mut Mode<Arc<str>>, item: impl Dsl) -> Usually<()> {
        Ok(if let Ok(Some(key)) = item.expr().head() {
            match key {
                "name" => mode.name.push(item.expr()?.tail()?.map(|x|x.trim()).unwrap_or("").into()),
                "info" => mode.info.push(item.expr()?.tail()?.map(|x|x.trim()).unwrap_or("").into()),
                "keys" => mode.keys.push(item.expr()?.tail()?.map(|x|x.trim()).unwrap_or("").into()),
                "mode" => if let Some(id) = item.expr()?.tail()?.head()? {
                    let mut submode = Mode::default();
                    Self::load_mode_one(&mut submode, item.expr()?.tail()?.tail()?)?;
                    mode.modes.insert(id.into(), submode);
                } else {
                    return Err(format!("load_mode_one: incomplete: {item:?}").into());
                },
                _ => mode.view.push(item.expr()?.unwrap().into()),
            }
        } else if let Ok(Some(word)) = item.word() {
            mode.view.push(word.into());
        } else {
            return Err(format!("load_mode_one: unexpected: {item:?}").into());
        })
    }
}
has!(Jack<'static>:      |self: App|self.jack);
has!(Pool:               |self: App|self.pool);
has!(Dialog:             |self: App|self.dialog);
has!(Clock:              |self: App|self.project.clock);
has!(Option<MidiEditor>: |self: App|self.project.editor);
has!(Selection:          |self: App|self.project.selection);
has!(Vec<MidiInput>:     |self: App|self.project.midi_ins);
has!(Vec<MidiOutput>:    |self: App|self.project.midi_outs);
has!(Vec<Scene>:         |self: App|self.project.scenes);
has!(Vec<Track>:         |self: App|self.project.tracks);
has!(Measure<TuiOut>:    |self: App|self.size);
has_clips!(              |self: App|self.pool.clips);
maybe_has!(Track: |self: App| { MaybeHas::<Track>::get(&self.project) };
                              { MaybeHas::<Track>::get_mut(&mut self.project) });
maybe_has!(Scene: |self: App| { MaybeHas::<Scene>::get(&self.project) };
                              { MaybeHas::<Scene>::get_mut(&mut self.project) });
impl HasClipsSize   for App { fn clips_size (&self) -> &Measure<TuiOut> { &self.project.inner_size } }
impl HasTrackScroll for App { fn track_scroll (&self) -> usize { self.project.track_scroll() } }
impl HasSceneScroll for App { fn scene_scroll (&self) -> usize { self.project.scene_scroll() } }
pub fn view_nil (_: &App) -> Box<dyn Render<TuiOut>> {
    Box::new(Fill::xy("·"))
}
content!(TuiOut:|self: App|Fill::xy(Stack::above(|add|{
    for dsl in self.mode.view.iter() { add(&Fill::xy(self.view(dsl.as_ref()))); }
})));
impl App {
    fn view <D: Dsl> (&self, index: D) -> Box<dyn Render<TuiOut>> {
        match index.src() {
            Ok(Some(src)) => render_dsl(self, src),
            Ok(None) => Box::new(Tui::fg(Color::Rgb(192, 192, 192), "empty view")),
            Err(e) => Box::new(format!("{e}")),
        }
    }
    pub fn update_clock (&self) {
        ViewCache::update_clock(&self.project.clock.view_cache, self.clock(), self.size.w() > 80)
    }
}
fn render_dsl <'t>  (
    state: &'t impl DslNs<'t, Box<dyn Render<TuiOut>>>,
    src:   &str
) -> Box<dyn Render<TuiOut>> {
    let err: Option<Box<dyn Error>> = match state.from(src) {
        Ok(Some(value)) => return value, Ok(None) => None, Err(e) => Some(e),
    };
    let (fg_1, bg_1) = (Color::Rgb(240, 160, 100), Color::Rgb(48, 0, 0));
    let (fg_2, bg_2) = (Color::Rgb(250, 200, 180), Color::Rgb(48, 0, 0));
    let (fg_3, bg_3) = (Color::Rgb(250, 200, 120), Color::Rgb(0, 0, 0));
    let bg = Color::Rgb(24, 0, 0);
    Box::new(col! {
        Tui::fg(bg, Fixed::y(1, Fill::x(RepeatH("▄")))),
        Tui::bg(bg, col! {
            Fill::x(Bsp::e(
                Tui::bold(true, Tui::fg_bg(fg_1, bg_1, " Render error: ")),
                Tui::fg_bg(fg_2, bg_2, err.map(|e|format!(" {e} "))),
            )),
            Fill::x(Align::x(Tui::fg_bg(fg_3, bg_3, format!(" {src} ")))),
        }),
        Tui::fg(bg, Fixed::y(1, Fill::x(RepeatH("▀")))),
    })
}

fn wrap_dialog (dialog: impl Content<TuiOut>) -> impl Content<TuiOut> {
    Fixed::xy(70, 23, Tui::fg_bg(Rgb(255,255,255), Rgb(16,16,16), Bsp::b(
        Repeat(" "), Outer(true, Style::default().fg(Tui::g(96))).enclose(dialog))))
}
impl ScenesView for App {
    fn h_scenes (&self) -> u16 {
        (self.height() as u16).saturating_sub(20)
    }
    fn w_side (&self) -> u16 {
        20
    }
    fn w_mid (&self) -> u16 {
        (self.width() as u16).saturating_sub(self.w_side())
    }
}
handle!(TuiIn:|self: App, input|{
    panic!("wat: {:?}", self.mode);
    for keys in self.mode.keys.iter() {
        panic!("{keys} {:?}", self.config.binds.read().unwrap());
        if let Some(binding) = self.config.binds.read().unwrap().get(keys.as_ref()) {
            panic!("{binding:?}");
        }
    }
    Ok(None)
});
#[derive(Debug)]
pub enum AppCommand { /* TODO */ }
impl Dialog {
    pub fn menu_selected (&self) -> Option<usize> {
        if let Self::Menu(selected) = self { Some(*selected) } else { None }
    }
    pub fn device_kind (&self) -> Option<usize> {
        if let Self::Device(index) = self { Some(*index) } else { None }
    }
    pub fn device_kind_next (&self) -> Option<usize> {
        self.device_kind().map(|index|(index + 1) % device_kinds().len())
    }
    pub fn device_kind_prev (&self) -> Option<usize> {
        self.device_kind().map(|index|index.overflowing_sub(1).0.min(device_kinds().len().saturating_sub(1)))
    }
    pub fn message (&self) -> Option<&str> {
        todo!()
    }
    pub fn browser (&self) -> Option<&Arc<Browser>> {
        todo!()
    }
    pub fn browser_target (&self) -> Option<&BrowserTarget> {
        todo!()
    }
}
#[tengri_proc::command(Option<Dialog>)] impl DialogCommand {
    fn open (dialog: &mut Option<Dialog>, new: Dialog) -> Perhaps<Self> {
        *dialog = Some(new);
        Ok(None)
    }
    fn close (dialog: &mut Option<Dialog>) -> Perhaps<Self> {
        *dialog = None;
        Ok(None)
    }
}

impl App {
    pub fn editor_focused (&self) -> bool {
        false
    }
    pub fn toggle_dialog (&mut self, mut dialog: Dialog) -> Dialog {
        std::mem::swap(&mut self.dialog, &mut dialog);
        dialog
    }
    pub fn toggle_editor (&mut self, value: Option<bool>) {
        //FIXME: self.editing.store(value.unwrap_or_else(||!self.is_editing()), Relaxed);
        let value = value.unwrap_or_else(||!self.editor().is_some());
        if value {
            // Create new clip in pool when entering empty cell
            if let Selection::TrackClip { track, scene } = *self.selection()
            && let Some(scene) = self.project.scenes.get_mut(scene)
            && let Some(slot)  = scene.clips.get_mut(track)
            && slot.is_none()
            && let Some(track) = self.project.tracks.get_mut(track)
            {
                let (index, mut clip) = self.pool.add_new_clip();
                // autocolor: new clip colors from scene and track color
                let color = track.color.base.mix(scene.color.base, 0.5);
                clip.write().unwrap().color = ItemColor::random_near(color, 0.2).into();
                if let Some(editor) = &mut self.project.editor {
                    editor.set_clip(Some(&clip));
                }
                *slot = Some(clip.clone());
                //Some(clip)
            } else {
                //None
            }
        } else if let Selection::TrackClip { track, scene } = *self.selection()
            && let Some(scene) = self.project.scenes.get_mut(scene)
            && let Some(slot) = scene.clips.get_mut(track)
            && let Some(clip) = slot.as_mut()
        {
            // Remove clip from arrangement when exiting empty clip editor
            let mut swapped = None;
            if clip.read().unwrap().count_midi_messages() == 0 {
                std::mem::swap(&mut swapped, slot);
            }
            if let Some(clip) = swapped {
                self.pool.delete_clip(&clip.read().unwrap());
            }
        }
    }
    pub fn browser (&self) -> Option<&Browser> {
        if let Dialog::Browser(_, ref b) = self.dialog { Some(b) } else { None }
    }
    pub fn device_pick (&mut self, index: usize) {
        self.dialog = Dialog::Device(index);
    }
    pub fn add_device (&mut self, index: usize) -> Usually<()> {
        match index {
            0 => {
                let name    = self.jack.with_client(|c|c.name().to_string());
                let midi    = self.project.track().expect("no active track").sequencer.midi_outs[0].port_name();
                let track   = self.track().expect("no active track");
                let port    = format!("{}/Sampler", &track.name);
                let connect = Connect::exact(format!("{name}:{midi}"));
                let sampler = if let Ok(sampler) = Sampler::new(
                    &self.jack, &port, &[connect], &[&[], &[]], &[&[], &[]]
                ) {
                    self.dialog = Dialog::None;
                    Device::Sampler(sampler)
                } else {
                    self.dialog = Dialog::Message("Failed to add device.".into());
                    return Err("failed to add device".into())
                };
                let track   = self.track_mut().expect("no active track");
                track.devices.push(sampler);
                Ok(())
            },
            1 => {
                todo!();
                Ok(())
            },
            _ => unreachable!(),
        }
    }
}

dsl_ns! { |app: App|

    Box<dyn Render<TuiOut>> => {
        ("bold", value: bool, x: Box<dyn Render<TuiOut>>) => Box::new(Tui::bold(value, x)),

        ("fg", color: Color, x: Box<dyn Render<TuiOut>>) => Box::new(Tui::fg(color, x)),
        ("bg", color: Color, x: Box<dyn Render<TuiOut>>) => Box::new(Tui::bg(color, x)),
        ("fg/bg", fg: Color, bg: Color, x: Box<dyn Render<TuiOut>>) => Box::new(Tui::fg_bg(fg, bg, x)),

        ("bsp/n", a: Box<dyn Render<TuiOut>>, b: Box<dyn Render<TuiOut>>) => Box::new(Bsp::n(a, b)),
        ("bsp/s", a: Box<dyn Render<TuiOut>>, b: Box<dyn Render<TuiOut>>) => Box::new(Bsp::s(a, b)),
        ("bsp/e", a: Box<dyn Render<TuiOut>>, b: Box<dyn Render<TuiOut>>) => Box::new(Bsp::e(a, b)),
        ("bsp/w", a: Box<dyn Render<TuiOut>>, b: Box<dyn Render<TuiOut>>) => Box::new(Bsp::w(a, b)),
        ("bsp/a", a: Box<dyn Render<TuiOut>>, b: Box<dyn Render<TuiOut>>) => Box::new(Bsp::a(a, b)),
        ("bsp/b", a: Box<dyn Render<TuiOut>>, b: Box<dyn Render<TuiOut>>) => Box::new(Bsp::b(a, b)),

        ("align/n", x: Box<dyn Render<TuiOut>>) => Box::new(Align::n(x)),
        ("align/s", x: Box<dyn Render<TuiOut>>) => Box::new(Align::s(x)),
        ("align/e", x: Box<dyn Render<TuiOut>>) => Box::new(Align::e(x)),
        ("align/w", x: Box<dyn Render<TuiOut>>) => Box::new(Align::w(x)),
        ("align/x", x: Box<dyn Render<TuiOut>>) => Box::new(Align::x(x)),
        ("align/y", x: Box<dyn Render<TuiOut>>) => Box::new(Align::y(x)),
        ("align/c", x: Box<dyn Render<TuiOut>>) => Box::new(Align::c(x)),

        ("fill/x",  x: Box<dyn Render<TuiOut>>) => Box::new(Fill::x(x)),
        ("fill/y",  x: Box<dyn Render<TuiOut>>) => Box::new(Fill::y(x)),
        ("fill/xy", x: Box<dyn Render<TuiOut>>) => Box::new(Fill::xy(x)),

        ("fixed/x",  x: u16, c: Box<dyn Render<TuiOut>>) => Box::new(Fixed::x(x, c)),
        ("fixed/y",  y: u16, c: Box<dyn Render<TuiOut>>) => Box::new(Fixed::y(y, c)),
        ("fixed/xy", x: u16, y: u16, c: Box<dyn Render<TuiOut>>) => Box::new(Fixed::xy(x, y, c)),

        ("min/x",  x: u16, c: Box<dyn Render<TuiOut>>) => Box::new(Min::x(x, c)),
        ("min/y",  y: u16, c: Box<dyn Render<TuiOut>>) => Box::new(Min::y(y, c)),
        ("min/xy", x: u16, y: u16, c: Box<dyn Render<TuiOut>>) => Box::new(Min::xy(x, y, c)),

        ("max/x",  x: u16, c: Box<dyn Render<TuiOut>>) => Box::new(Max::x(x, c)),
        ("max/y",  y: u16, c: Box<dyn Render<TuiOut>>) => Box::new(Max::y(y, c)),
        ("max/xy", x: u16, y: u16, c: Box<dyn Render<TuiOut>>) => Box::new(Max::xy(x, y, c)),

        ":view/menu" => app.view(stringify!(
            (bg :color/bg (bsp/s :view/ports/outs (bsp/n :view/ports/ins :view/modes)))
        )),

        ":view/modes" => Box::new({
            let modes  = app.config.modes.clone();
            let height = (modes.read().unwrap().len() * 2) as u16;
            Fixed::y(height,
                Fill::x(Stack::south(move|add: &mut dyn FnMut(&dyn Render<TuiOut>)|{
                    for (index, (id, profile)) in modes.read().unwrap().iter().enumerate() {
                        let bg   = if index == 0 { Rgb(48,64,32) } else { Rgb(16, 32, 24) };
                        let name = profile.name.get(0).map(|x|x.as_ref()).unwrap_or("<no name>");
                        let info = profile.info.get(0).map(|x|x.as_ref()).unwrap_or("<no info>");
                        let fg1  = Rgb(224, 192, 128);
                        let fg2  = Rgb(224, 128,  32);
                        add(&Fixed::y(2, Fill::x(Tui::bg(bg, Bsp::s(
                            Fill::x(Bsp::a(Fill::x(Align::w(Tui::fg(fg1, name))),
                                           Fill::x(Align::e(Tui::fg(fg2, id))))),
                            Fill::x(Align::w(info)))))));
                    }
                })))}),

        ":view/ports/outs" =>
            app.view(stringify!((fill/x (fixed/y 3
                (bsp/a (fill/x (align/w "L AUDIO OUT")
                       (bsp/a "MIDI OUT" (fill/x (align/e "AUDIO OUT R"))))))))),
        ":view/ports/ins" =>
            app.view(stringify!(fill/x (fixed/y 3
                (bsp/a (fill/x (align/w "L AUDIO IN ")
                       (bsp/a "MIDI IN " (fill/x (align/e "AUDIO IN  R")))))))),
        ":view/browse" =>
            app.view(stringify!(bsp/s
                (padding/xy 3 1 :view/browse-title) (enclose (fg (g 96)) :view/browser))),
        ":view/browse/title" =>
            Box::new(Fill::x(Align::w(FieldV(Default::default(),
                match app.dialog.browser_target().unwrap() {
                   BrowserTarget::SaveProject     => "Save project:",
                   BrowserTarget::LoadProject     => "Load project:",
                   BrowserTarget::ImportSample(_) => "Import sample:",
                   BrowserTarget::ExportSample(_) => "Export sample:",
                   BrowserTarget::ImportClip(_)   => "Import clip:",
                   BrowserTarget::ExportClip(_)   => "Export clip:",
                }, Shrink::x(3, Fixed::y(1, Tui::fg(Tui::g(96), RepeatH("🭻")))))))),
        ":view/device" => {
            let selected = app.dialog.device_kind().unwrap();
            Box::new(Bsp::s(Tui::bold(true, "Add device"), Map::south(1,
                move||device_kinds().iter(),
                move|label: &&'static str, i|{
                    let bg = if i == selected { Rgb(64,128,32) } else { Rgb(0,0,0) };
                    let lb = if i == selected { "[ " } else { "  " };
                    let rb = if i == selected { " ]" } else { "  " };
                    Fill::x(Tui::bg(bg, Bsp::e(lb, Bsp::w(rb, "FIXME device name")))) }))) },
        //(":view/options", view_options),
    };

    bool => {
        ":focused/editor"      => app.project.editor.is_some(),
        ":focused/dialog"      => !matches!(app.dialog, Dialog::None),
        ":focused/message"     => matches!(app.dialog, Dialog::Message(..)),
        ":focused/add_device"  => matches!(app.dialog, Dialog::Device(..)),
        ":focused/browser"     => app.dialog.browser().is_some(),
        ":focused/pool/import" => matches!(app.pool.mode, Some(PoolMode::Import(..))),
        ":focused/pool/export" => matches!(app.pool.mode, Some(PoolMode::Export(..))),
        ":focused/pool/rename" => matches!(app.pool.mode, Some(PoolMode::Rename(..))),
        ":focused/pool/length" => matches!(app.pool.mode, Some(PoolMode::Length(..))),
        ":focused/clip"        => !app.editor_focused() && matches!(app.selection(),
            Selection::TrackClip{..}),
        ":focused/track"       => !app.editor_focused() && matches!(app.selection(),
            Selection::Track(..)),
        ":focused/scene"       => !app.editor_focused() && matches!(app.selection(),
            Selection::Scene(..)),
        ":focused/mix"         => !app.editor_focused() && matches!(app.selection(),
            Selection::Mix),
    };

    ItemTheme => {
        ":_theme_stub" => Default::default()
    };

    Dialog => {
        ":dialog/none"          => Dialog::None,
        ":dialog/options"       => Dialog::Options,
        ":dialog/device"        => Dialog::Device(0),
        ":dialog/device/prev"   => Dialog::Device(0),
        ":dialog/device/next"   => Dialog::Device(0),
        ":dialog/help"          => Dialog::Help(0),
        ":dialog/menu"          => Dialog::Menu(0),
        ":dialog/save"          => Dialog::Browser(BrowserTarget::SaveProject,
            Browser::new(None).unwrap().into()),
        ":dialog/load"          => Dialog::Browser(BrowserTarget::LoadProject,
            Browser::new(None).unwrap().into()),
        ":dialog/import/clip"   => Dialog::Browser(BrowserTarget::ImportClip(Default::default()),
            Browser::new(None).unwrap().into()),
        ":dialog/export/clip"   => Dialog::Browser(BrowserTarget::ExportClip(Default::default()),
            Browser::new(None).unwrap().into()),
        ":dialog/import/sample" => Dialog::Browser(BrowserTarget::ImportSample(Default::default()),
            Browser::new(None).unwrap().into()),
        ":dialog/export/sample" => Dialog::Browser(BrowserTarget::ExportSample(Default::default()),
            Browser::new(None).unwrap().into()),
    };

    Selection => {
        ":select/scene"      => app.selection().select_scene(app.tracks().len()),
        ":select/scene/next" => app.selection().select_scene_next(app.scenes().len()),
        ":select/scene/prev" => app.selection().select_scene_prev(),
        ":select/track"      => app.selection().select_track(app.tracks().len()),
        ":select/track/next" => app.selection().select_track_next(app.tracks().len()),
        ":select/track/prev" => app.selection().select_track_prev(),
    };

    Option<u7> => {
        ":editor/pitch" => Some((app.editor().as_ref().map(|e|e.get_note_pos()).unwrap() as u8).into())
    };

    Option<usize> => {
        ":selected/scene" => app.selection().scene(),
        ":selected/track" => app.selection().track(),
    };

    Option<Arc<RwLock<MidiClip>>> => {
        ":selected/clip" => if let Selection::TrackClip { track, scene } = app.selection() {
            app.scenes()[*scene].clips[*track].clone()
        } else {
            None
        }
    };

    AppCommand => {
        ("stop-all") => todo!(),//app.project.stop_all(),
        ("enqueue", clip:  Option<Arc<RwLock<MidiClip>>>) => todo!(),
        ("history", delta: isize)                 => todo!(),
        ("zoom",    zoom:  usize)                 => todo!(),
        ("select",  selection: Selection)         => todo!(),
        ("dialog"  / command: DialogCommand)      => todo!(),
        ("project" / command: ArrangementCommand) => todo!(),
        ("clock"   / command: ClockCommand)       => todo!(),
        ("sampler" / command: SamplerCommand)     => todo!(),
        ("pool"    / command: PoolCommand)        => todo!(),
        ("pool"    / editor:  MidiEditCommand)    => todo!(),
    };

    DialogCommand;

    ArrangementCommand;

    ClockCommand;

    SamplerCommand;

    PoolCommand;

    MidiEditCommand;

    Color => {
        ("g", n: u8) => Color::Rgb(n, n, n),
        ("rgb", red: u8, green: u8, blue: u8) => Color::Rgb(red, green, blue),
        ":color/bg" => Color::Rgb(28, 32, 36),

    };

}

dsl_ns! { num |app: App|
    u8;
    u16 => {
        ":w/sidebar"       => app.project.w_sidebar(app.editor().is_some()),
        ":h/sample-detail" => 6.max(app.height() as u16 * 3 / 9),
    };
    usize => {
        ":scene-count"      => app.scenes().len(),
        ":track-count"      => app.tracks().len(),
        ":device-kind"      => app.dialog.device_kind().unwrap_or(0),
        ":device-kind/next" => app.dialog.device_kind_next().unwrap_or(0),
        ":device-kind/prev" => app.dialog.device_kind_prev().unwrap_or(0),
    };
    isize;
}

///////////////////////////////////////////////////////////////////////////////////////////////////

//#[derive(Clone, Debug)]
//pub enum DialogCommand {
    //Open { dialog: Dialog },
    //Close
//}

//impl Command<Option<Dialog>> for DialogCommand {
    //fn execute (self, state: &mut Option<Dialog>) -> Perhaps<Self> {
        //match self {
            //Self::Open { dialog } => {
                //*state = Some(dialog);
            //},
            //Self::Close => {
                //*state = None;
            //}
        //};
        //Ok(None)
    //}
//}

//dsl!(DialogCommand: |self: Dialog, iter|todo!());
//Dsl::take(&mut self.dialog, iter));

//#[tengri_proc::command(Option<Dialog>)]//Nope.
//impl DialogCommand {
    //fn open (dialog: &mut Option<Dialog>, new: Dialog) -> Perhaps<Self> {
        //*dialog = Some(new);
        //Ok(None)
    //}
    //fn close (dialog: &mut Option<Dialog>) -> Perhaps<Self> {
        //*dialog = None;
        //Ok(None)
    //}
//}
//
//dsl_bind!(AppCommand: App {
    //enqueue  = |app, clip:  Option<Arc<RwLock<MidiClip>>>| { todo!() };
    //history  = |app, delta: isize| { todo!() };
    //zoom     = |app, zoom:  usize| { todo!() };
    //stop_all = |app| { app.tracks_stop_all(); Ok(None) };
    ////dialog   = |app, command: DialogCommand|
        ////Ok(command.delegate(&mut app.dialog, |c|Self::Dialog{command: c})?);
    //project  = |app, command: ArrangementCommand|
        //Ok(command.delegate(&mut app.project, |c|Self::Project{command: c})?);
    //clock    = |app, command: ClockCommand|
        //Ok(command.execute(app.clock_mut())?.map(|c|Self::Clock{command: c}));
    //sampler  = |app, command: SamplerCommand|
        //Ok(app.project.sampler_mut().map(|s|command.delegate(s, |command|Self::Sampler{command}))
            //.transpose()?.flatten());
    //pool     = |app, command: PoolCommand| {
        //let undo = command.clone().delegate(&mut app.pool, |command|AppCommand::Pool{command})?;
        //// update linked editor after pool action
        //match command {
            //// autoselect: automatically load selected clip in editor
            //PoolCommand::Select { .. } |
            //// autocolor: update color in all places simultaneously
            //PoolCommand::Clip { command: PoolClipCommand::SetColor { .. } } => {
                //let clip = app.pool.clip().clone();
                //app.editor_mut().map(|editor|editor.set_clip(clip.as_ref()))
            //},
            //_ => None
        //};
        //Ok(undo)
    //};
    //select   = |app, selection: Selection| {
        //*app.project.selection_mut() = selection;
        ////todo!
        ////if let Some(ref mut editor) = app.editor_mut() {
            ////editor.set_clip(match selection {
                ////Selection::TrackClip { track, scene } if let Some(Some(Some(clip))) = app
                    ////.project
                    ////.scenes.get(scene)
                    ////.map(|s|s.clips.get(track))
                ////=>
                    ////Some(clip),
                ////_ =>
                    ////None
            ////});
        ////}
        //Ok(None)
        ////("select"  [t: usize, s: usize] Some(match (t.expect("no track"), s.expect("no scene")) {
            ////(0, 0) => Self::Select(Selection::Mix),
            ////(t, 0) => Self::Select(Selection::Track(t)),
            ////(0, s) => Self::Select(Selection::Scene(s)),
            ////(t, s) => Self::Select(Selection::TrackClip { track: t, scene: s }) })))
        //// autoedit: load focused clip in editor.
    //};
    ////fn color (app: &mut App, theme: ItemTheme) -> Perhaps<Self> {
        ////Ok(app.set_color(Some(theme)).map(|theme|Self::Color{theme}))
    ////}
    ////fn launch (app: &mut App) -> Perhaps<Self> {
        ////app.project.launch();
        ////Ok(None)
    ////}
    //toggle_editor = |app, value: bool|{ app.toggle_editor(Some(value)); Ok(None) };
    //editor = |app, command: MidiEditCommand| Ok(if let Some(editor) = app.editor_mut() {
        //let undo = command.clone().delegate(editor, |command|AppCommand::Editor{command})?;
        //// update linked sampler after editor action
        //app.project.sampler_mut().map(|sampler|match command {
            //// autoselect: automatically select sample in sampler
            //MidiEditCommand::SetNotePos { pos } => { sampler.set_note_pos(pos); },
            //_ => {}
        //});
        //undo
    //} else {
        //None
    //});
//});
//take!(ClockCommand       |state: App, iter|Take::take(state.clock(), iter));
//take!(MidiEditCommand    |state: App, iter|Ok(state.editor().map(|x|Take::take(x, iter)).transpose()?.flatten()));
//take!(PoolCommand        |state: App, iter|Take::take(&state.pool, iter));
//take!(SamplerCommand     |state: App, iter|Ok(state.project.sampler().map(|x|Take::take(x, iter)).transpose()?.flatten()));
//take!(ArrangementCommand |state: App, iter|Take::take(&state.project, iter));
//take!(DialogCommand      |state: App, iter|Take::take(&state.dialog, iter));
//has_editor!(|self: App|{
    //editor = self.editor;
    //editor_w = {
        //let size      = self.size.w();
        //let editor    = self.editor.as_ref().expect("missing editor");
        //let time_len  = editor.time_len().get();
        //let time_zoom = editor.time_zoom().get().max(1);
        //(5 + (time_len / time_zoom)).min(size.saturating_sub(20)).max(16)
    //};
    //editor_h = 15;
    //is_editing = self.editor.is_some();
//});

                //Bsp::s("",
                    //Map::south(1,
                        //move||app.config.binds.layers.iter()
                            //.filter_map(|a|(a.0)(app).then_some(a.1))
                            //.flat_map(|a|a)
                            //.filter_map(|x|if let Value::Exp(_, iter)=x.value{ Some(iter) } else { None })
                            //.skip(offset)
                            //.take(20),
                        //|mut b,i|Fixed::x(60, Align::w(Bsp::e("(", Bsp::e(
                            //b.next().map(|t|Fixed::x(16, Align::w(Tui::fg(Rgb(64,224,0), format!("{}", t.value))))),
                            //Bsp::e(" ", Align::w(format!("{}", b.0.0.trim()))))))))))),

            //Dialog::Browser(BrowserTarget::Load, browser) => {
                //"bobcat".boxed()
                    ////Bsp::s(
                        ////Fill::x(Align::w(Margin::xy(1, 1, Bsp::e(
                            ////Tui::bold(true, " Load project: "),
                            ////Shrink::x(3, Fixed::y(1, RepeatH("🭻"))))))),
                        ////Outer(true, Style::default().fg(Tui::g(96)))
                            ////.enclose(Fill::xy(browser)))
            //},
            //Dialog::Browser(BrowserTarget::Export, browser) => {
                //"bobcat".boxed()
                    ////Bsp::s(
                        ////Fill::x(Align::w(Margin::xy(1, 1, Bsp::e(
                            ////Tui::bold(true, " Export: "),
                            ////Shrink::x(3, Fixed::y(1, RepeatH("🭻"))))))),
                        ////Outer(true, Style::default().fg(Tui::g(96)))
                            ////.enclose(Fill::xy(browser)))
            //},
            //Dialog::Browser(BrowserTarget::Import, browser) => {
                //"bobcat".boxed()
                    ////Bsp::s(
                        ////Fill::x(Align::w(Margin::xy(1, 1, Bsp::e(
                            ////Tui::bold(true, " Import: "),
                            ////Shrink::x(3, Fixed::y(1, RepeatH("🭻"))))))),
                        ////Outer(true, Style::default().fg(Tui::g(96)))
                            ////.enclose(Fill::xy(browser)))
            //},
//
    //pub fn view_meters_input (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.sampler().map(|s|
            //s.view_meters_input())
    //}
    //pub fn view_meters_output (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.sampler().map(|s|
            //s.view_meters_output())
    //}
    //pub fn view_history (&self) -> impl Content<TuiOut> {
        //Fixed::y(1, Fill::x(Align::w(FieldH(self.color,
            //format!("History ({})", self.history.len()),
                //self.history.last().map(|last|Fill::x(Align::w(format!("{:?}", last.0))))))))
    //}
    //pub fn view_status_h2 (&self) -> impl Content<TuiOut> {
        //self.update_clock();
        //let theme     = self.color;
        //let clock     = self.clock();
        //let playing   = clock.is_rolling();
        //let cache     = clock.view_cache.clone();
        ////let selection = self.selection().describe(self.tracks(), self.scenes());
        //let hist_len  = self.history.len();
        //let hist_last = self.history.last();
        //Fixed::y(2, Stack::east(move|add: &mut dyn FnMut(&dyn Render<TuiOut>)|{
            //add(&Fixed::x(5, Tui::bg(if playing { Rgb(0, 128, 0) } else { Rgb(128, 64, 0) },
                //Either::new(false, // TODO
                    //Thunk::new(move||Fixed::x(9, Either::new(playing,
                        //Tui::fg(Rgb(0, 255, 0),   " PLAYING "),
                        //Tui::fg(Rgb(255, 128, 0), " STOPPED ")))
                    //),
                    //Thunk::new(move||Fixed::x(5, Either::new(playing,
                        //Tui::fg(Rgb(0, 255, 0),   Bsp::s(" 🭍🭑🬽 ", " 🭞🭜🭘 ",)),
                        //Tui::fg(Rgb(255, 128, 0), Bsp::s(" ▗▄▖ ", " ▝▀▘ ",))))
                    //)
                //)
            //)));
            //add(&" ");
            //{
                //let cache = cache.read().unwrap();
                //add(&Fixed::x(15, Align::w(Bsp::s(
                    //FieldH(theme, "Beat", cache.beat.view.clone()),
                    //FieldH(theme, "Time", cache.time.view.clone()),
                //))));
                //add(&Fixed::x(13, Align::w(Bsp::s(
                    //Fill::x(Align::w(FieldH(theme, "BPM", cache.bpm.view.clone()))),
                    //Fill::x(Align::w(FieldH(theme, "SR ", cache.sr.view.clone()))),
                //))));
                //add(&Fixed::x(12, Align::w(Bsp::s(
                    //Fill::x(Align::w(FieldH(theme, "Buf", cache.buf.view.clone()))),
                    //Fill::x(Align::w(FieldH(theme, "Lat", cache.lat.view.clone()))),
                //))));
                ////add(&Bsp::s(
                    //////Fill::x(Align::w(FieldH(theme, "Selected", Align::w(selection)))),
                    ////Fill::x(Align::w(FieldH(theme, format!("History ({})", hist_len),
                        ////hist_last.map(|last|Fill::x(Align::w(format!("{:?}", last.0))))))),
                    ////""
                ////));
                //////if let Some(last) = self.history.last() {
                    //////add(&FieldV(theme, format!("History ({})", self.history.len()),
                        //////Fill::x(Align::w(format!("{:?}", last.0)))));
                //////}
            //}
        //}))
    //}
    //pub fn view_status_v (&self) -> impl Content<TuiOut> + use<'_> {
        //self.update_clock();
        //let cache   = self.project.clock.view_cache.read().unwrap();
        //let theme   = self.color;
        //let playing = self.clock().is_rolling();
        //Tui::bg(theme.darker.rgb, Fixed::xy(20, 5, Outer(true, Style::default().fg(Tui::g(96))).enclose(
            //col!(
                //Fill::x(Align::w(Bsp::e(
                    //Align::w(Tui::bg(if playing { Rgb(0, 128, 0) } else { Rgb(128, 64, 0) },
                        //Either::new(false, // TODO
                            //Thunk::new(move||Fixed::x(9, Either::new(playing,
                                //Tui::fg(Rgb(0, 255, 0),   " PLAYING "),
                                //Tui::fg(Rgb(255, 128, 0), " STOPPED ")))
                            //),
                            //Thunk::new(move||Fixed::x(5, Either::new(playing,
                                //Tui::fg(Rgb(0, 255, 0),   Bsp::s(" 🭍🭑🬽 ", " 🭞🭜🭘 ",)),
                                //Tui::fg(Rgb(255, 128, 0), Bsp::s(" ▗▄▖ ", " ▝▀▘ ",))))
                            //)
                        //)
                    //)),
                    //Bsp::s(
                        //FieldH(theme, "Beat", cache.beat.view.clone()),
                        //FieldH(theme, "Time", cache.time.view.clone()),
                    //),
                //))),
                //Fill::x(Align::w(FieldH(theme, "BPM", cache.bpm.view.clone()))),
                //Fill::x(Align::w(FieldH(theme, "SR ", cache.sr.view.clone()))),
                //Fill::x(Align::w(FieldH(theme, "Buf", Bsp::e(cache.buf.view.clone(), Bsp::e(" = ", cache.lat.view.clone()))))),
            //))))
    //}
    //pub fn view_status (&self) -> impl Content<TuiOut> + use<'_> {
        //self.update_clock();
        //let cache = self.project.clock.view_cache.read().unwrap();
        //view_status(Some(self.project.selection.describe(self.tracks(), self.scenes())),
            //cache.sr.view.clone(), cache.buf.view.clone(), cache.lat.view.clone())
    //}
    //pub fn view_transport (&self) -> impl Content<TuiOut> + use<'_> {
        //self.update_clock();
        //let cache = self.project.clock.view_cache.read().unwrap();
        //view_transport(self.project.clock.is_rolling(),
            //cache.bpm.view.clone(), cache.beat.view.clone(), cache.time.view.clone())
    //}
    //pub fn view_editor (&self) -> impl Content<TuiOut> + use<'_> {
        //let bg = self.editor()
            //.and_then(|editor|editor.clip().clone())
            //.map(|clip|clip.read().unwrap().color.darker)
            //.unwrap_or(self.color.darker);
        //Fill::xy(Tui::bg(bg.rgb, self.editor()))
    //}
    //pub fn view_editor_status (&self) -> impl Content<TuiOut> + use<'_> {
        //self.editor().map(|e|Fixed::x(20, Outer(true, Style::default().fg(Tui::g(96))).enclose(
            //Fill::y(Align::n(Bsp::s(e.clip_status(), e.edit_status()))))))
    //}
    //pub fn view_midi_ins_status (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.view_midi_ins_status(self.color)
    //}
    //pub fn view_midi_outs_status (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.view_midi_outs_status(self.color)
    //}
    //pub fn view_audio_ins_status (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.view_audio_ins_status(self.color)
    //}
    //pub fn view_audio_outs_status (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.view_audio_outs_status(self.color)
    //}
    //pub fn view_scenes (&self) -> impl Content<TuiOut> + use<'_> {
        //Bsp::e(
            //Fixed::x(20, Align::nw(self.project.view_scenes_names())),
            //self.project.view_scenes_clips(),
        //)
    //}
    //pub fn view_scenes_names (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.view_scenes_names()
    //}
    //pub fn view_scenes_clips (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.view_scenes_clips()
    //}
    //pub fn view_tracks_inputs <'a> (&'a self) -> impl Content<TuiOut> + use<'a> {
        //Fixed::y(1 + self.project.midi_ins.len() as u16,
            //self.project.view_inputs(self.color))
    //}
    //pub fn view_tracks_outputs <'a> (&'a self) -> impl Content<TuiOut> + use<'a> {
        //self.project.view_outputs(self.color)
    //}
    //pub fn view_tracks_devices <'a> (&'a self) -> impl Content<TuiOut> + use<'a> {
        //Fixed::y(4, self.project.view_track_devices(self.color))
    //}
    //pub fn view_tracks_names <'a> (&'a self) -> impl Content<TuiOut> + use<'a> {
        //Fixed::y(2, self.project.view_track_names(self.color))
    //}
    //pub fn view_pool (&self) -> impl Content<TuiOut> + use<'_> {
        //Fixed::x(20, Bsp::s(
            //Fill::x(Align::w(FieldH(self.color, "Clip pool:", ""))),
            //Fill::y(Align::n(Tui::bg(Rgb(0, 0, 0), Outer(true, Style::default().fg(Tui::g(96)))
                //.enclose(PoolView(&self.pool)))))))
    //}
    //pub fn view_samples_keys (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.sampler().map(|s|s.view_list(true, self.editor().unwrap()))
    //}
    //pub fn view_samples_grid (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.sampler().map(|s|s.view_grid())
    //}
    //pub fn view_sample_viewer (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.sampler().map(|s|s.view_sample(self.editor().unwrap().get_note_pos()))
    //}
    //pub fn view_sample_info (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.sampler().map(|s|s.view_sample_info(self.editor().unwrap().get_note_pos()))
    //}
    //pub fn view_sample_status (&self) -> impl Content<TuiOut> + use<'_> {
        //self.project.sampler().map(|s|Outer(true, Style::default().fg(Tui::g(96))).enclose(
            //Fill::y(Align::n(s.view_sample_status(self.editor().unwrap().get_note_pos())))))
    //}
            ////let options = ||["Projects", "Settings", "Help", "Quit"].iter();
            ////let option  = |a,i|Tui::fg(Rgb(255,255,255), format!("{}", a));
            ////Bsp::s(Tui::bold(true, "tek!"), Bsp::s("", Map::south(1, options, option)))