use crate::core::*;
use super::*;

pub fn draw (
    buf:      &mut Buffer,
    area:     Rect,
    phrase:   Option<&Phrase>,
    ppq:      usize,
    time:     usize,
    time0:    usize,
    time_z:   usize,
    note:     usize,
    note0:    usize,
    style:    Option<Style>,
) -> Usually<Rect> {
    let now   = 0;
    let notes = &[];
    match time_z {
         1 => "1/384",
         2 => "1/192",
         3 => "1/128",
         4 => "1/96",
         6 => "1/64",
         8 => "1/48",
        12 => "1/32",
        16 => "1/24",
        24 => "1/16",
        32 => "1/12",
        48 => "1/8",
        64 => "1/6",
        96 => "1/4",
       128 => "1/3",
       192 => "1/2",
       384 => "1/1",
       _ => ""
    }.blit(buf, area.x, area.y, Some(Style::default().dim()));
    keys(buf, area, note0, notes)?;
    timer(buf, area, time0, now);
    if let Some(phrase) = phrase {
        lanes(buf, area, phrase, ppq, time_z, time0, note0);
    }
    let style = style.unwrap_or_else(||{Style::default().green().not_dim()});
    cursor(buf, area, style, time, note);
    //footer(buf, area, note0, note, time0, time, time_z);
    Ok(area)
}

pub fn timer (
    buf:   &mut Buffer,
    area:  Rect,
    time0: usize,
    now:   usize
) {
    let x = area.x + 5;
    for step in time0..(time0+area.width as usize).saturating_sub(5) {
        buf.set_string(x + step as u16, area.y, &"-", if step == now {
            Style::default().yellow().bold().not_dim()
        } else {
            Style::default()
        });
    }
}

pub fn keys (
    buf:   &mut Buffer,
    area:  Rect,
    note0: usize,
    notes: &[bool],
) -> Usually<Rect> {
    let bw = Style::default().dim();
    let Rect { x, y, width, height } = area;
    let h = height.saturating_sub(2);
    for index in 0..h {
        let y = y + h - index;
        let key = KEYS_VERTICAL[(index % 6) as usize];
        key.blit(buf, x + 1, y, Some(bw));
        "█".blit(buf, x + 2, y, Some(bw));
        "|---".repeat(width.saturating_sub(6) as usize).blit(buf, x + 5, y, Some(bw.black()));
        let note_a = note0 + (index * 2) as usize;
        if note_a % 12 == 0 {
            let octave = format!("C{}", (note_a / 12) as i8 - 2);
            octave.blit(buf, x + 3, y, None);
            continue
        }
        let note_b = note0 + (index * 2) as usize;
        if note_b % 12 == 0 {
            let octave = format!("C{}", (note_b / 12) as i8 - 2);
            octave.blit(buf, x + 3, y, None);
            continue
        }
    }
    Ok(area)
}

pub fn lanes (
    buf:    &mut Buffer,
    area:   Rect,
    phrase: &Phrase,
    ppq:    usize,
    time_z: usize,
    time0:  usize,
    note0:  usize,
) {
    let Rect { x, y, width, height } = area;
    let time0    = time0 / time_z;
    let time1    = time0 + width  as usize;
    let note1    = note0 + height as usize;
    let bg       = Style::default();
    let (bw, wh) = (bg.dim(), bg.white());
    let offset   = 5;
    for x in x+offset..x+width-offset {
        let step = (x-offset) as usize * time_z;
        if step % ppq == 0 {
            "|".blit(buf, x as u16, y, Some(Style::default().dim()));
        }
        let bar = 4 * ppq;
        if step % bar == 0 {
            format!("{}", (step/bar)+1)
                .blit(buf, x as u16, y, Some(Style::default().bold().not_dim()));
        }
        let (a, b) = (step, step + time_z);
        for index in 0..height-2 {
            let note_a = note0 + index as usize * 2;
            let note_b = note0 + index as usize * 2 + 1;
            let (character, style) = match (
                contains_note_on(phrase, u7::from_int_lossy(note_a as u8), a, b),
                contains_note_on(phrase, u7::from_int_lossy(note_b as u8), a, b),
            ) {
              (true, true)   => ("█", wh),
              (false, true)  => ("▄", wh),
              (true, false)  => ("▀", wh),
              (false, false) => ("·", bw),
            };
            let y = y + height.saturating_sub(index+2) as u16;
            character.blit(buf, x, y, Some(style));
        }
    }
}

pub fn cursor (
    buf:   &mut Buffer,
    area:  Rect,
    style: Style,
    time:  usize,
    note:  usize
) {
    let x = area.x + 5 + time as u16;
    let y = area.y + 1 + note as u16 / 2;
    let c = if note % 2 == 0 { "▀" } else { "▄" };
    c.blit(buf, x, y, Some(style));
}

pub fn footer (
    buf:    &mut Buffer,
    area:   Rect,
    note0:  usize,
    note:   usize,
    time0:  usize,
    time:   usize,
    time_z: usize,
) {
    let Rect { mut x, y, width, height } = area;
    buf.set_string(x, y + height, format!("├{}┤", "-".repeat((width - 2).into())),
        Style::default().dim());
    buf.set_string(x, y + height + 2, format!("├{}┤", "-".repeat((width - 2).into())),
        Style::default().dim());
    x = x + 2;
    {
        for (_, [letter, title, value]) in [
            ["S", &format!("ync"),  &format!("<4/4>")],
            ["Q", &format!("uant"), &format!("<1/{}>", 4 * time_z)],
            ["N", &format!("ote"),  &format!("{} ({}-{})", note0 + note, note0, "X")],
            ["T", &format!("ime"),  &format!("{} ({}-{})", time0 + time, time0 + 1, "X")],
        ].iter().enumerate() {
            buf.set_string(x, y + height + 1, letter, Style::default().bold().yellow().dim());
            x = x + 1;
            buf.set_string(x, y + height + 1, &title, Style::default().bold().dim());
            x = x + title.len() as u16 + 1;
            buf.set_string(x, y + height + 1, &value, Style::default().not_dim());
            x = x + value.len() as u16;
            buf.set_string(x, y + height + 1, "  ", Style::default().dim());
            x = x + 2;
        }
    }
}