use crate::*;

impl<'a, T: TransportViewState> Content for TransportView<'a, T> {
    type Engine = Tui;
    fn content (&self) -> impl Widget<Engine = Tui> {
        let state = self.0;
        let focused = state.transport_focused();
        lay!(
            state.transport_selected().wrap(focused, TransportFocus::PlayPause, &Styled(
                None,
                match state.transport_state() {
                    Some(TransportState::Rolling)  => "▶ PLAYING",
                    Some(TransportState::Starting) => "READY ...",
                    Some(TransportState::Stopped)  => "⏹ STOPPED",
                    _ => unreachable!(),
                }
            ).min_xy(11, 2).push_x(1)).align_x().fill_x(),

            row!(
                state.transport_selected().wrap(focused, TransportFocus::Bpm, &Outset::X(1u16, {
                    let bpm = state.bpm_value();
                    row! { "BPM ", format!("{}.{:03}", bpm as usize, (bpm * 1000.0) % 1000.0) }
                })),
                //let quant = state.focus().wrap(state.focused(), TransportFocus::Quant, &Outset::X(1u16, row! {
                    //"QUANT ", ppq_to_name(state.0.quant as usize)
                //})),
                state.transport_selected().wrap(focused, TransportFocus::Sync, &Outset::X(1u16, row! {
                    "SYNC ",  pulses_to_name(state.sync_value() as usize)
                }))
            ).align_w().fill_x(),

            state.transport_selected().wrap(focused, TransportFocus::Clock, &{
                let time1 = state.format_beat();
                let time2 = state.format_msu();
                row!("B" ,time1.as_str(), " T", time2.as_str()).outset_x(1)
            }).align_e().fill_x(),

        ).fill_x().bg(Color::Rgb(40, 50, 30))
    }
}

impl Content for SequencerTui {
    type Engine = Tui;
    fn content (&self) -> impl Widget<Engine = Tui> {
        col!(
            widget(&TransportView(self)),
            Split::right(20,
                widget(&PhrasesView(self)),
                widget(&PhraseView(self)),
            ).min_y(20)
        )
    }
}

/// Display mode of arranger
#[derive(Clone, PartialEq)]
pub enum ArrangerMode {
    /// Tracks are rows
    Horizontal,
    /// Tracks are columns
    Vertical(usize),
}

/// Arranger display mode can be cycled
impl ArrangerMode {
    /// Cycle arranger display mode
    pub fn to_next (&mut self) {
        *self = match self {
            Self::Horizontal  => Self::Vertical(1),
            Self::Vertical(1) => Self::Vertical(2),
            Self::Vertical(2) => Self::Vertical(2),
            Self::Vertical(0) => Self::Horizontal,
            Self::Vertical(_) => Self::Vertical(0),
        }
    }
}

/// Layout for standalone arranger app.
impl Content for ArrangerTui {
    type Engine = Tui;
    fn content (&self) -> impl Widget<Engine = Tui> {
        let arranger_focused = self.arranger_focused();
        Split::up(
            1,
            TransportView(self),
            Split::down(
                self.splits[0],
                lay!(
                    Layers::new(move |add|{
                        match self.mode {
                            ArrangerMode::Horizontal =>
                                add(&arranger_content_horizontal(self))?,
                            ArrangerMode::Vertical(factor) =>
                                add(&arranger_content_vertical(self, factor))?
                        };
                        add(&self.size)
                    })
                        .grow_y(1)
                        .border(Lozenge(Style::default()
                            .bg(TuiTheme::border_bg())
                            .fg(TuiTheme::border_fg(arranger_focused)))),
                    widget(&self.size),
                    widget(&format!("[{}] Arranger", if self.entered {
                        "■"
                    } else {
                        " "
                    }))
                        .fg(TuiTheme::title_fg(arranger_focused))
                        .push_x(1),
                ),
                Split::right(
                    self.splits[1],
                    PhrasesView(self),
                    PhraseView(self),
                )
            )
        )
    }
}

// TODO: Display phrases always in order of appearance
impl<'a, T: PhrasesViewState> Content for PhrasesView<'a, T> {
    type Engine = Tui;
    fn content (&self) -> impl Widget<Engine = Tui> {
        let focused = self.0.phrases_focused();
        let entered = self.0.entered();
        let phrases = self.0.phrases();
        let selected_phrase = self.0.phrase();
        let mode    = self.0.mode();
        let content = col!(
            (i, phrase) in phrases.iter().enumerate() => Layers::new(|add|{
                let Phrase { ref name, color, length, .. } = *phrase.read().unwrap();
                let mut length = PhraseLength::new(length, None);
                if let Some(PhrasesMode::Length(phrase, new_length, focus)) = mode {
                    if focused && i == *phrase {
                        length.pulses = *new_length;
                        length.focus  = Some(*focus);
                    }
                }
                let length   = length.align_e().fill_x();
                let row1     = lay!(format!(" {i}").align_w().fill_x(), length).fill_x();
                let mut row2 = format!(" {name}");
                if let Some(PhrasesMode::Rename(phrase, _)) = mode {
                    if focused && i == *phrase {
                        row2 = format!("{row2}▄"); 
                    }
                };
                let row2 = TuiStyle::bold(row2, true);
                add(&col!(row1, row2).fill_x().bg(color.base.rgb))?;
                if focused && i == selected_phrase {
                    add(&CORNERS)?;
                }
                Ok(())
            })
        );
        let border_color = if focused {Color::Rgb(100, 110, 40)} else {Color::Rgb(70, 80, 50)};
        let border       = Lozenge(Style::default().bg(Color::Rgb(40, 50, 30)).fg(border_color));
        let content      = content.fill_xy().bg(Color::Rgb(28, 35, 25)).border(border);
        let title_color  = if focused {Color::Rgb(150, 160, 90)} else {Color::Rgb(120, 130, 100)};
        let upper_left   = format!("[{}] Phrases", if entered {"■"} else {" "});
        let upper_right  = format!("({})", self.0.phrases().len());
        lay!(
            content,
            TuiStyle::fg(upper_left.to_string(),  title_color).push_x(1).align_nw().fill_xy(),
            TuiStyle::fg(upper_right.to_string(), title_color).pull_x(1).align_ne().fill_xy(),
        )
    }
}

impl<'a, T: PhraseViewState> Content for PhraseView<'a, T> {
    type Engine = Tui;
    fn content (&self) -> impl Widget<Engine = Tui> {
        let phrase    = self.0.phrase();
        let size      = self.0.size();
        let focused   = self.0.phrase_focused();
        let entered   = self.0.entered();
        let keys      = self.0.keys();
        let buffer    = self.0.buffer();
        let note_len  = self.0.note_len();
        let note_axis = self.0.note_axis();
        let time_axis = self.0.time_axis();
        let FixedAxis  { start: note_start, point: note_point, clamp: note_clamp }
            = *note_axis.read().unwrap();
        let ScaledAxis { start: time_start, point: time_point, clamp: time_clamp, scale: time_scale }
            = *time_axis.read().unwrap();
        //let color = Color::Rgb(0,255,0);
        //let color = phrase.as_ref().map(|p|p.read().unwrap().color.base.rgb).unwrap_or(color);
        let keys = CustomWidget::new(|to:[u16;2]|Ok(Some(to.clip_w(5))), move|to: &mut TuiOutput|{
            Ok(if to.area().h() >= 2 {
                to.buffer_update(to.area().set_w(5), &|cell, x, y|{
                    let y = y + (note_start / 2) as u16;
                    if x < keys.area.width && y < keys.area.height {
                        *cell = keys.get(x, y).clone()
                    }
                });
            })
        }).fill_y();
        let notes_bg_null = Color::Rgb(28, 35, 25);
        let notes = CustomWidget::new(|to|Ok(Some(to)), move|to: &mut TuiOutput|{
            let area = to.area();
            let h = area.h() as usize;
            size.set_wh(area.w(), h);
            let mut axis = note_axis.write().unwrap();
            if let Some(point) = axis.point {
                if point.saturating_sub(axis.start) > (h * 2).saturating_sub(1) {
                    axis.start += 2;
                }
            }
            Ok(if to.area().h() >= 2 {
                let area = to.area();
                to.buffer_update(area, &move |cell, x, y|{
                    cell.set_bg(notes_bg_null);
                    let src_x = (x as usize + time_start) * time_scale;
                    let src_y = y as usize + note_start / 2;
                    if src_x < buffer.width && src_y < buffer.height - 1 {
                        buffer.get(src_x, buffer.height - src_y - 2).map(|src|{
                            cell.set_symbol(src.symbol());
                            cell.set_fg(src.fg);
                            cell.set_bg(src.bg);
                        });
                    }
                });
            })
        }).fill_x();
        let cursor = CustomWidget::new(|to|Ok(Some(to)), move|to: &mut TuiOutput|{
            Ok(if focused && entered {
                let area = to.area();
                if let (Some(time), Some(note)) = (time_point, note_point) {
                    let x1 = area.x() + (time / time_scale) as u16;
                    let x2 = x1 + (note_len / time_scale) as u16;
                    let y = area.y() + note.saturating_sub(note_start) as u16 / 2;
                    let c = if note % 2 == 0 { "▀" } else { "▄" };
                    for x in x1..x2 {
                        to.blit(&c, x, y, Some(Style::default().fg(Color::Rgb(0,255,0))));
                    }
                }
            })
        });
        let playhead_inactive = Style::default().fg(Color::Rgb(255,255,255)).bg(Color::Rgb(40,50,30));
        let playhead_active   = playhead_inactive.clone().yellow().bold().not_dim();
        let playhead = CustomWidget::new(
            |to:[u16;2]|Ok(Some(to.clip_h(1))),
            move|to: &mut TuiOutput|{
                if let Some(_) = phrase {
                    let now = self.0.now().get() as usize; // TODO FIXME: self.now % phrase.read().unwrap().length;
                    let time_clamp = time_clamp
                        .expect("time_axis of sequencer expected to be clamped");
                    for x in 0..(time_clamp/time_scale).saturating_sub(time_start) {
                        let this_step = time_start + (x + 0) * time_scale;
                        let next_step = time_start + (x + 1) * time_scale;
                        let x         = to.area().x() + x as u16;
                        let active    = this_step <= now && now < next_step;
                        let character = if active { "|" } else { "·" };
                        let style     = if active { playhead_active } else { playhead_inactive };
                        to.blit(&character, x, to.area.y(), Some(style));
                    }
                }
                Ok(())
            }
        ).push_x(6).align_sw();
        let border_color    = if focused{Color::Rgb(100, 110, 40)}else{Color::Rgb(70,   80,  50)};
        let title_color     = if focused{Color::Rgb(150, 160, 90)}else{Color::Rgb(120, 130, 100)};
        let border          = Lozenge(Style::default().bg(Color::Rgb(40, 50, 30)).fg(border_color));
        let note_area       = lay!(notes, cursor).fill_x();
        let piano_roll      = row!(keys, note_area).fill_x();
        let content         = piano_roll.bg(Color::Rgb(40, 50, 30)).border(border);
        let content         = lay!(content, playhead);
        let mut upper_left  = format!("[{}] Sequencer", if entered {"■"} else {" "});
        if let Some(phrase) = phrase {
            upper_left = format!("{upper_left}: {}", phrase.read().unwrap().name);
        }
        let mut lower_right = format!("┤{}├", size.format());
        lower_right = format!("┤Zoom: {}├─{lower_right}", pulses_to_name(time_scale));
        //lower_right = format!("Zoom: {} (+{}:{}*{}|{})",
            //pulses_to_name(time_scale),
            //time_start, time_point.unwrap_or(0),
            //time_scale, time_clamp.unwrap_or(0),
        //);
        if focused && entered {
            lower_right = format!("┤Note: {} {}├─{lower_right}",
                note_axis.read().unwrap().point.unwrap(),
                pulses_to_name(note_len));
            //lower_right = format!("Note: {} (+{}:{}|{})  {upper_right}",
                //pulses_to_name(*note_len),
                //note_start,
                //note_point.unwrap_or(0),
                //note_clamp.unwrap_or(0),
            //);
        }
        let upper_right = if let Some(phrase) = phrase {
            format!("┤Length: {}├", phrase.read().unwrap().length)
        } else {
            String::new()
        };
        lay!(
            content,
            TuiStyle::fg(upper_left.to_string(),  title_color).push_x(1).align_nw().fill_xy(),
            TuiStyle::fg(upper_right.to_string(), title_color).pull_x(1).align_ne().fill_xy(),
            TuiStyle::fg(lower_right.to_string(), title_color).pull_x(1).align_se().fill_xy(),
        )
    }
}

impl Content for PhraseLength {
    type Engine = Tui;
    fn content (&self) -> impl Widget<Engine = Tui> {
        Layers::new(move|add|{
            match self.focus {
                None => add(&row!(
                    " ", self.bars_string(),
                    ".", self.beats_string(),
                    ".", self.ticks_string(),
                    " "
                )),
                Some(PhraseLengthFocus::Bar) => add(&row!(
                    "[", self.bars_string(),
                    "]", self.beats_string(),
                    ".", self.ticks_string(),
                    " "
                )),
                Some(PhraseLengthFocus::Beat) => add(&row!(
                    " ", self.bars_string(),
                    "[", self.beats_string(),
                    "]", self.ticks_string(),
                    " "
                )),
                Some(PhraseLengthFocus::Tick) => add(&row!(
                    " ", self.bars_string(),
                    ".", self.beats_string(),
                    "[", self.ticks_string(),
                    "]"
                )),
            }
        })
    }
}