use crate::*;

impl Sampler {

    pub fn view_grid (&self) -> impl Draw<TuiOut> + Layout<TuiOut> + use<'_> {
        let cells_x     = 8u16;
        let cells_y     = 8u16;
        let cell_width  = 10u16;
        let cell_height = 2u16;
        //let width       = cells_x * cell_width;
        //let height      = cells_y * cell_height;
        //let cols = Map::east(
            //cell_width,
            //move||0..cells_x,
            //move|x, _|Map::south(
                //cell_height,
                //move||0..cells_y,
                //move|y, _|self.view_grid_cell("........", x, y, cell_width, cell_height)
            //)
        //);
        //cols
        //Thunk::new(|to: &mut TuiOut|{
        //})
        "TODO"
    }

    pub fn view_grid_cell <'a> (
        &'a self, name: &'a str, x: u16, y: u16, w: u16, h: u16
    ) -> impl Draw<TuiOut> + use<'a> {
        let cursor = self.cursor();
        let hi_fg = Color::Rgb(64, 64, 64);
        let hi_bg = if y == 0 { Color::Reset } else { Color::Rgb(64, 64, 64) /*prev*/ };
        let tx_fg = if let Some((index, _)) = self.recording
            && index % 8 == x as usize
            && index / 8 == y as usize
        {
            Color::Rgb(255, 64, 0)
        } else {
            Color::Rgb(255, 255, 255)
        };
        let tx_bg = if x as usize == cursor.0 && y as usize == cursor.1 {
            Color::Rgb(96, 96, 96)
        } else {
            Color::Rgb(64, 64, 64)
        };
        let lo_fg = Color::Rgb(64, 64, 64);
        let lo_bg = if y == 7 { Color::Reset } else { tx_bg };
        Fixed::xy(w, h, Bsp::s(
            Fixed::y(1, Tui::fg_bg(hi_fg, hi_bg, RepeatH(Phat::<()>::LO))),
            Bsp::n(
                Fixed::y(1, Tui::fg_bg(lo_fg, lo_bg, RepeatH(Phat::<()>::HI))),
                Fill::x(Fixed::y(1, Tui::fg_bg(tx_fg, tx_bg, name))),
            ),
        ))
    }

    const _EMPTY: &[(f64, f64)] = &[(0., 0.), (1., 1.), (2., 2.), (0., 2.), (2., 0.)];

    pub fn view_list <'a, T: NotePoint + NoteRange> (
        &'a self, compact: bool, editor: &T
    ) -> impl Draw<TuiOut> + 'a {
        let note_lo = editor.get_note_lo();
        let note_pt = editor.get_note_pos();
        let note_hi = editor.get_note_hi();
        Fixed::x(if compact { 4 } else { 12 }, Map::south(
            1,
            move||(note_lo..=note_hi).rev(),
            move|note, _index| {
                //let offset = |a|Push::y(i as u16, Align::n(Fixed::y(1, Fill::x(a))));
                let mut bg = if note == note_pt { Tui::g(64) } else { Color::Reset };
                let mut fg = Tui::g(160);
                if let Some(mapped) = &self.mapped[note] {
                    let sample = mapped.read().unwrap();
                    fg = if note == note_pt {
                        sample.color.lightest.rgb
                    } else {
                        Tui::g(224)
                    };
                    bg = if note == note_pt {
                        sample.color.light.rgb
                    } else {
                        sample.color.base.rgb
                    };
                }
                if let Some((index, _)) = self.recording {
                    if note == index {
                        bg = if note == note_pt { Color::Rgb(96,24,0) } else { Color::Rgb(64,16,0) };
                        fg = Color::Rgb(224,64,32)
                    }
                }
                Tui::fg_bg(fg, bg, format!("{note:3} {}", self.view_list_item(note, compact)))
            }))
    }

    pub fn view_list_item (&self, note: usize, compact: bool) -> String {
        if compact {
            String::default()
        } else {
            draw_list_item(&self.mapped[note])
        }
    }

    pub fn view_sample (&self, note_pt: usize) -> impl Draw<TuiOut> + use<'_> {
        Outer(true, Style::default().fg(Tui::g(96)))
            .enclose(Fill::xy(draw_viewer(if let Some((_, Some(sample))) = &self.recording {
                Some(sample)
            } else if let Some(sample) = &self.mapped[note_pt] {
                Some(sample)
            } else {
                None
            })))
    }

    pub fn view_sample_info (&self, note_pt: usize) -> impl Draw<TuiOut> + use<'_> {
        Fill::x(Fixed::y(1, draw_info(if let Some((_, Some(sample))) = &self.recording {
            Some(sample)
        } else if let Some(sample) = &self.mapped[note_pt] {
            Some(sample)
        } else {
            None
        })))
    }

    pub fn view_sample_status (&self, note_pt: usize) -> impl Draw<TuiOut> + use<'_> {
        Fixed::x(20, draw_info_v(if let Some((_, Some(sample))) = &self.recording {
            Some(sample)
        } else if let Some(sample) = &self.mapped[note_pt] {
            Some(sample)
        } else {
            None
        }))
    }

    pub fn view_status (&self, index: usize) -> impl Draw<TuiOut> {
        draw_status(self.mapped[index].as_ref())
    }

    pub fn view_meters_input (&self) -> impl Draw<TuiOut> + use<'_> {
        draw_meters(&self.input_meters)
    }

    pub fn view_meters_output (&self) -> impl Draw<TuiOut> + use<'_> {
        draw_meters(&self.output_meters)
    }
}

fn draw_meters (meters: &[f32]) -> impl Draw<TuiOut> + use<'_> {
    Tui::bg(Black, Fixed::x(2, Map::east(1, ||meters.iter(), |value, _index|{
        Fill::y(RmsMeter(*value))
    })))
}

fn draw_list_item (sample: &Option<Arc<RwLock<Sample>>>) -> String {
    if let Some(sample) = sample {
        let sample = sample.read().unwrap();
        format!("{:8}", sample.name)
        //format!("{:8} {:3} {:6}-{:6}/{:6}",
            //sample.name,
            //sample.gain,
            //sample.start,
            //sample.end,
            //sample.channels[0].len()
        //)
    } else {
        String::from("........")
    }
}

fn draw_viewer (sample: Option<&Arc<RwLock<Sample>>>) -> impl Draw<TuiOut> + Layout<TuiOut> + use<'_> {
    let min_db = -64.0;
    Thunk::new(move|to: &mut TuiOut|{
        let [x, y, width, height] = to.area();
        let area = Rect { x, y, width, height };
        if let Some(sample) = &sample {
            let sample = sample.read().unwrap();
            let start  = sample.start  as f64;
            let end    = sample.end    as f64;
            let length = end - start;
            let step   = length / width as f64;
            let mut t  = start;
            let mut lines = vec![];
            while t < end {
                let chunk = &sample.channels[0][t as usize..((t + step) as usize).min(sample.end)];
                let total: f32 = chunk.iter().map(|x|x.abs()).sum();
                let count = chunk.len() as f32;
                let meter = 10. * (total / count).log10();
                let x = t as f64;
                let y = meter as f64;
                lines.push(Line::new(x, min_db, x, y, Color::Green));
                t += step / 2.;
            }
            Canvas::default()
                .x_bounds([sample.start as f64, sample.end as f64])
                .y_bounds([min_db, 0.])
                .paint(|ctx| {
                    for line in lines.iter() {
                        ctx.draw(line);
                    }
                    //FIXME: proportions
                    //let text = "press record to finish sampling";
                    //ctx.print(
                        //(width - text.len() as u16) as f64 / 2.0,
                        //height as f64 / 2.0,
                        //text.red()
                    //);
                }).render(area, &mut to.buffer);
        } else {
            Canvas::default()
                .x_bounds([0.0, width  as f64])
                .y_bounds([0.0, height as f64])
                .paint(|_ctx| {
                    //let text = "press record to begin sampling";
                    //ctx.print(
                        //(width - text.len() as u16) as f64 / 2.0,
                        //height as f64 / 2.0,
                        //text.red()
                    //);
                })
                .render(area, &mut to.buffer);
        }
    })
}

fn draw_info (sample: Option<&Arc<RwLock<Sample>>>) -> impl Draw<TuiOut> + Layout<TuiOut> + use<'_> {
    When(sample.is_some(), Thunk::new(move|to: &mut TuiOut|{
        let sample = sample.unwrap().read().unwrap();
        let theme  = sample.color;
        to.place(&row!(
            FieldH(theme, "Name",   format!("{:<10}", sample.name.clone())),
            FieldH(theme, "Length", format!("{:<8}",  sample.channels[0].len())),
            FieldH(theme, "Start",  format!("{:<8}",  sample.start)),
            FieldH(theme, "End",    format!("{:<8}",  sample.end)),
            FieldH(theme, "Trans",  "0"),
            FieldH(theme, "Gain",   format!("{}",     sample.gain)),
        ))
    }))
}

fn draw_info_v (sample: Option<&Arc<RwLock<Sample>>>) -> impl Draw<TuiOut> + Layout<TuiOut> + use<'_> {
    Either::new(sample.is_some(), Thunk::new(move|to: &mut TuiOut|{
        let sample = sample.unwrap().read().unwrap();
        let theme  = sample.color;
        to.place(&Fixed::x(20, col!(
            Fill::x(Align::w(FieldH(theme, "Name  ", format!("{:<10}", sample.name.clone())))),
            Fill::x(Align::w(FieldH(theme, "Length", format!("{:<8}",  sample.channels[0].len())))),
            Fill::x(Align::w(FieldH(theme, "Start ", format!("{:<8}",  sample.start)))),
            Fill::x(Align::w(FieldH(theme, "End   ", format!("{:<8}",  sample.end)))),
            Fill::x(Align::w(FieldH(theme, "Trans ", "0"))),
            Fill::x(Align::w(FieldH(theme, "Gain  ", format!("{}",     sample.gain)))),
        )))
    }), Thunk::new(|to: &mut TuiOut|to.place(&Tui::fg(Red, col!(
        Tui::bold(true, "× No sample."),
        "[r] record",
        "[Shift-F9] import",
    )))))
}

fn draw_status (sample: Option<&Arc<RwLock<Sample>>>) -> impl Draw<TuiOut> + Layout<TuiOut> {
    Tui::bold(true, Tui::fg(Tui::g(224), sample
        .map(|sample|{
            let sample = sample.read().unwrap();
            format!("Sample {}-{}", sample.start, sample.end)
        })
        .unwrap_or_else(||"No sample".to_string())))
}

fn draw_sample (
    to: &mut TuiOut, x: u16, y: u16, note: Option<&u7>, sample: &Sample, focus: bool
) -> Usually<usize> {
    let style = if focus { Style::default().green() } else { Style::default() };
    if focus {
        to.blit(&"🬴", x+1, y, Some(style.bold()));
    }
    let label1 = format!("{:3} {:12}",
        note.map(|n|n.to_string()).unwrap_or(String::default()),
        sample.name);
    let label2 = format!("{:>6} {:>6}  +0.0",
        sample.start,
        sample.end);
    to.blit(&label1, x+2, y, Some(style.bold()));
    to.blit(&label2, x+3+label1.len()as u16, y, Some(style));
    Ok(label1.len() + label2.len() + 4)
}