keysA = {
  \repeat unfold 2 {
    R1 | R1 | R1 |
  } \alternative {
    { R1 |}
    { R1 |}
  }
}

keysB = { R1 | R1 | R1 | R1 |}

keysTransition = \relative c' {
  \repeat volta 2 {
    <cis fis a>1 | <b e gis>1   |
    <a d fis>1   | <a cis fis>1 |
  }

  %% TODO
  \repeat volta 4 { R1 | R1 |}
}

keysThree = {
  \time 6/8
  \repeat unfold 2 { R2. | R2. |}
  R2. | R2. | R2. |
  \time 7/8 R8*7 |
}

keysMartaRekado = \relative c' {
  \repeat unfold 2 {
    \time 5/8
    cis''16 a fis cis r cis8 fis a16  |
    \time 7/8
    gis8 e b e16 e8 fis16 r16 b,8 e16 |
  } \alternative {
    { \time 2/4 cis8. a16 b a gis a |}
    { \time 2/4 cis8. a16 b a gis a |}
  }

  \time 3/4
  d,16 a fis a fis' a
  gis e b e gis b  |
  a fis d fis a cis
  b gis e gis e' d |

  %% TODE simplify
  fis cis a gis a cis
  b e e, a b cis  |

  %% TODO
  \time 7/8
  a a' fis cis cis d8 d8 r r8. |
}

keysReprise = \relative c' {
  \time 4/4
  \repeat unfold 2 {
    <cis fis a cis>2 ~               <cis es a cis>2  |
    <c f a d>4. ~ <cis fis a cis>8 ~ <cis fis a cis>2 |
    <cis fis a fis'>2 ~              <cis es a fis'>2 |
    <c f a d>4. ~ <cis fis a cis>8 ~ <cis fis a cis>2 |
  }
}

keysFinal = \transpose c d { \relative c' {
  \repeat volta 4 {
    %% TODO: simplify + use more simple arpeggios
    \tuplet 6/2 { g'8 e cis g e b } e,2   b'16 cis fis8 |
    g16 c e c e fis g8 ~ g2 |

    \tuplet 6/2 { b8 g e b e, cis }
    b16 e, a cis g' b e fis g a b c
    <b g >16 r8 <a fis >16 r8 g16 fis e b g e b4
  }

  %% TODO: simplify more!
  <a'' e,, cis a >16 g
  e cis a' e cis e cis a e a e cis a e
  <c'' g, e c >4*1/6
  g e g e c e c g c g
  <d' a g g, >4*1/6 e g b g b d b d e fis16 g

  <a e,, cis a >16 g
  e cis a' e cis e cis a e a e cis a e
  dis8 a' r8 c'16 dis fis1.
}}

keyboard = \new PianoStaff <<
  \new Staff \relative c' {
    %% Intro
    \time 4/4
    R1*8

    \repeat unfold 2 {
      \key b \minor
      \keysA
      \key e \major
      \keysB
    }

    \set PianoStaff.midiInstrument = #"choir aahs"
    \key fis \minor
    \keysTransition
    \keysThree

    \set PianoStaff.midiInstrument = #"oboe"
    \keysMartaRekado

    \set PianoStaff.midiInstrument = #"string ensemble 1"
    \keysReprise
    \set PianoStaff.midiInstrument = #"electric piano 2"
    \keysFinal
  }
>>