use crate::*;

fn track_widths (tracks: &[ArrangementTrack]) -> Vec<(usize, usize)> {
    let mut widths = vec![];
    let mut total = 0;
    for track in tracks.iter() {
        let width = track.width;
        widths.push((width, total));
        total += width;
    }
    widths.push((0, total));
    widths
}

pub fn arranger_content_vertical (
    view: &ArrangerView<Tui>,
    factor: usize
) -> impl Widget<Engine = Tui> + use<'_> {
    let tracks   = view.model.tracks.as_slice();
    let scenes   = view.model.scenes.as_slice();
    let cols     = track_widths(tracks);
    let rows     = ArrangementScene::ppqs(scenes, factor);
    let bg       = view.color;
    let clip_bg  = TuiTheme::border_bg();
    let sep_fg   = TuiTheme::separator_fg(false);
    let header_h = 3u16;//5u16;
    let scenes_w = 3 + ArrangementScene::longest_name(scenes) as u16; // x of 1st track
    let clock    = &view.sequencer.transport.model.clock;
    let arrangement = Layers::new(move |add|{
        let rows: &[(usize, usize)] = rows.as_ref();
        let cols: &[(usize, usize)] = cols.as_ref();
        let any_size = |_|Ok(Some([0,0]));
        // column separators
        add(&CustomWidget::new(any_size, move|to: &mut TuiOutput|{
            let style = Some(Style::default().fg(sep_fg));
            Ok(for x in cols.iter().map(|col|col.1) {
                let x = scenes_w + to.area().x() + x as u16;
                for y in to.area().y()..to.area().y2() { to.blit(&"▎", x, y, style); }
            })
        }))?;
        // row separators
        add(&CustomWidget::new(any_size, move|to: &mut TuiOutput|{
            Ok(for y in rows.iter().map(|row|row.1) {
                let y = to.area().y() + (y / PPQ) as u16 + 1;
                if y >= to.buffer.area.height { break }
                for x in to.area().x()..to.area().x2().saturating_sub(2) {
                    if x < to.buffer.area.x && y < to.buffer.area.y {
                        let cell = to.buffer.get_mut(x, y);
                        cell.modifier = Modifier::UNDERLINED;
                        cell.underline_color = sep_fg;
                    }
                }
            })
        }))?;
        // track titles
        let header = row!((track, w) in tracks.iter().zip(cols.iter().map(|col|col.0))=>{
            // name and width of track
            let name   = track.name.read().unwrap();
            let player = &track.player;
            let max_w  = w.saturating_sub(1).min(name.len()).max(2);
            let name   = format!("▎{}", &name[0..max_w]);
            let name   = TuiStyle::bold(name, true);
            // beats elapsed
            let elapsed = if let Some((_, Some(phrase))) = player.phrase.as_ref() {
                let length  = phrase.read().unwrap().length;
                let elapsed = player.pulses_since_start().unwrap();
                let elapsed = clock.timebase().format_beats_1_short(
                    (elapsed as usize % length) as f64
                );
                format!("▎+{elapsed:>}")
            } else {
                String::from("▎")
            };
            // beats until switchover
            let until_next = player.next_phrase.as_ref().map(|(t, _)|{
                let target  = t.pulse.get();
                let current = clock.current.pulse.get();
                if target > current {
                    let remaining = target - current;
                    format!("▎-{:>}", clock.timebase().format_beats_0_short(remaining))
                } else {
                    String::new()
                }
            }).unwrap_or(String::from("▎"));
            // name of active MIDI input
            let input = format!("▎>{}", track.player.midi_inputs.get(0)
                .map(|port|port.short_name())
                .transpose()?
                .unwrap_or("(none)".into()));
            // name of active MIDI output
            let output = format!("▎<{}", track.player.midi_outputs.get(0)
                .map(|port|port.short_name())
                .transpose()?
                .unwrap_or("(none)".into()));
            col!(name, /*input, output,*/ until_next, elapsed)
                .min_xy(w as u16, header_h)
                .bg(track.color.rgb)
                .push_x(scenes_w)
        });
        // scene titles
        let scene_name = |scene: &ArrangementScene, playing: bool, height|row!(
            if playing { "▶ " } else { "  " },
            TuiStyle::bold(scene.name.read().unwrap().as_str(), true),
        ).fixed_xy(scenes_w, height);
        // scene clips
        let scene_clip = |scene: &ArrangementScene, track: usize, w: u16, h: u16|Layers::new(move |add|{
            let mut bg = clip_bg;
            match (tracks.get(track), scene.clips.get(track)) {
                (Some(track), Some(Some(phrase))) => {
                    let name = &(phrase as &Arc<RwLock<Phrase>>).read().unwrap().name;
                    let name = format!("{}", name);
                    let max_w = name.len().min((w as usize).saturating_sub(2));
                    let color = phrase.read().unwrap().color;
                    add(&name.as_str()[0..max_w].push_x(1).fixed_x(w))?;
                    bg = color.dark.rgb;
                    if let Some((_, Some(ref playing))) = track.player.phrase {
                        if *playing.read().unwrap() == *phrase.read().unwrap() {
                            bg = color.light.rgb
                        }
                    };
                },
                _ => {}
            };
            add(&Background(bg))
        }).fixed_xy(w, h);
        // tracks and scenes
        let content = col!(
            // scenes:
            (scene, pulses) in scenes.iter().zip(rows.iter().map(|row|row.0)) => {
                let height = 1.max((pulses / PPQ) as u16);
                let playing = scene.is_playing(tracks);
                Stack::right(move |add| {
                    // scene title:
                    add(&scene_name(scene, playing, height).bg(scene.color.rgb))?;
                    // clip per track:
                    Ok(for (track, w) in cols.iter().map(|col|col.0).enumerate() {
                        add(&scene_clip(scene, track, w as u16, height))?;
                    })
                }).fixed_y(height)
            }
        ).fixed_y((view.size.h() as u16).saturating_sub(header_h));
        // full grid with header and footer
        add(&col!(header, content))?;
        // cursor
        add(&CustomWidget::new(any_size, move|to: &mut TuiOutput|{
            let area     = to.area();
            let focused  = view.focused;
            let selected = view.selected;
            let get_track_area = |t: usize| [
                scenes_w + area.x() + cols[t].1 as u16, area.y(),
                cols[t].0 as u16, area.h(),
            ];
            let get_scene_area = |s: usize| [
                area.x(), header_h + area.y() + (rows[s].1 / PPQ) as u16,
                area.w(), (rows[s].0 / PPQ) as u16
            ];
            let get_clip_area = |t: usize, s: usize| [
                scenes_w + area.x() + cols[t].1 as u16,
                header_h + area.y() + (rows[s].1/PPQ) as u16,
                cols[t].0 as u16,
                (rows[s].0 / PPQ) as u16
            ];
            let mut track_area: Option<[u16;4]> = None;
            let mut scene_area: Option<[u16;4]> = None;
            let mut clip_area:  Option<[u16;4]> = None;
            let area = match selected {
                ArrangementEditorFocus::Mix => area,
                ArrangementEditorFocus::Track(t) => {
                    track_area = Some(get_track_area(t));
                    area
                },
                ArrangementEditorFocus::Scene(s) => {
                    scene_area = Some(get_scene_area(s));
                    area
                },
                ArrangementEditorFocus::Clip(t, s) => {
                    track_area = Some(get_track_area(t));
                    scene_area = Some(get_scene_area(s));
                    clip_area  = Some(get_clip_area(t, s));
                    area
                },
            };
            let bg = TuiTheme::border_bg();
            if let Some([x, y, width, height]) = track_area {
                to.fill_fg([x,         y, 1, height], bg);
                to.fill_fg([x + width, y, 1, height], bg);
            }
            if let Some([_, y, _, height]) = scene_area {
                to.fill_ul([area.x(), y - 1,          area.w(), 1], bg);
                to.fill_ul([area.x(), y + height - 1, area.w(), 1], bg);
            }
            Ok(if focused {
                to.render_in(if let Some(clip_area) = clip_area { clip_area }
                else if let Some(track_area) = track_area { track_area.clip_h(header_h) }
                else if let Some(scene_area) = scene_area { scene_area.clip_w(scenes_w) }
                else { area.clip_w(scenes_w).clip_h(header_h) }, &CORNERS)?
            })
        }))
    }).bg(bg.rgb);
    let color = TuiTheme::title_fg(view.focused);
    let size  = format!("{}x{}", view.size.w(), view.size.h());
    let lower_right = TuiStyle::fg(size, color).pull_x(1).align_se().fill_xy();
    lay!(arrangement, lower_right)
}