// port of cracklebass by pestis (originally on TIC-80)

include "../include/microw8-api.cwa"

const MUSIC_DATA = 0x20000;

export fn upd() {
    let inline t = 32!32 / 16;
    let inline p = t / 1024;

    let channel:i32;

    loop channels {
        let inline e = t * channel?MUSIC_DATA / 8;
        let lazy pattern = (8 * channel + p)?(MUSIC_DATA + 56);
        let lazy n = !!pattern * (8 * pattern + e / 16 % 8)?MUSIC_DATA;
        let inline prev_ctrl = (channel * 6)?80;
        (channel * 6)?80 = if n {
            let inline base_note = 12 + 12 * channel?(MUSIC_DATA + 4) + n;
            let inline pitch_drop = e % 16 * channel?(MUSIC_DATA + 94);
            let inline key_pattern = p?(MUSIC_DATA + 8*4 + 56);
            let inline key = select(key_pattern, (8 * key_pattern + t / 128 % 8)?MUSIC_DATA, 1);
            (channel * 6)?83 = base_note - pitch_drop / 4 + key;
            prev_ctrl & 0xfc | (e / 8 & 2) | 1
        } else {
            prev_ctrl & 0xfe
        };

        branch_if (channel := channel + 1) < 4: channels;
    }
}

data 80 {
    i8(
        0x44, 0, 0, 0, 0x50, 0x40,
        0x4, 0x50, 0, 0, 0x80, 0x80,
        0x40, 0x80, 0, 0, 0x40, 0x40,
        0, 0, 0, 0, 0x50, 0x50
    )
}

data MUSIC_DATA {
    i8(
 16, 2, 8, 8, 1, 2, 2, 3, 1, 0,
  1,13,16, 0, 1, 8, 1, 0, 1,13,
 16, 1, 1, 8, 1, 0, 8,13,13, 0,
 16,13, 1, 0, 1, 0, 1, 0, 1, 1,
  1, 0, 0, 0, 1, 0,13, 1, 1, 1,
  6, 8, 1, 1, 6, 8, 1, 1, 2, 1,
  2, 1, 2, 0, 0, 0, 0, 3, 3, 3,
  5, 0, 0, 2, 1, 2, 1, 2, 1, 2,
  0, 4, 4, 0, 4, 4, 4, 4, 0, 0,
  0, 0, 6, 6, 0, 0, 0, 8
    )
}