export default [
  {
    id: 'jazz-251-major',
    name: 'ii–V–I',
    rn: ['ii7', 'V7', 'Imaj7'],
    degrees: [2, 7, 0],
    qualities: ['min7', 'dom7', 'maj7'],
    bars: [1, 1, 2],
    mode: 'major',
    songs: ['All The Things You Are', 'Tune Up — Miles Davis', 'Honeysuckle Rose'],
    tip: 'The 7th of each chord resolves down a half-step to the 3rd of the next — that two-note thread is the whole progression.',
  },
  {
    id: 'jazz-251-minor',
    name: 'minor ii–V–i',
    rn: ['iiø7', 'V7', 'i7'],
    degrees: [2, 7, 0],
    qualities: ['half_dim', 'dom7', 'min7'],
    bars: [1, 1, 2],
    mode: 'minor',
    songs: ['Autumn Leaves (bridge)', 'Blue Bossa', 'Beautiful Love'],
    tip: 'Same engine as the major ii–V–I, darker fuel: the ♭5 of the iiø7 is the ♭9 colour waiting to happen on the V7.',
  },
  {
    id: 'jazz-rhythm-a',
    name: 'Rhythm changes turnaround',
    rn: ['Imaj7', 'vi7', 'ii7', 'V7'],
    degrees: [0, 9, 2, 7],
    qualities: ['maj7', 'min7', 'min7', 'dom7'],
    bars: [1, 1, 1, 1],
    mode: 'major',
    songs: ['I Got Rhythm — Gershwin', 'Oleo — Sonny Rollins', 'Blue Moon'],
    tip: 'A loop, not a line — bar 4 hands you straight back to bar 1. Learn it as one circular shape your hands repeat.',
  },
  {
    id: 'jazz-625',
    name: 'vi–ii–V–I circle',
    rn: ['vi7', 'ii7', 'V7', 'Imaj7'],
    degrees: [9, 2, 7, 0],
    qualities: ['min7', 'min7', 'dom7', 'maj7'],
    bars: [1, 1, 1, 1],
    mode: 'major',
    songs: ['Fly Me to the Moon', 'Autumn Leaves (A section, relative view)'],
    tip: 'Pure circle-of-fifths motion: every root falls a fifth. If you can hear this one, you can predict half the jazz repertoire.',
  },
  {
    id: 'jazz-blues',
    name: 'Jazz blues (12-bar)',
    rn: ['I7', 'IV7', 'I7', 'I7', 'IV7', 'IV7', 'I7', 'VI7', 'ii7', 'V7', 'I7', 'V7'],
    degrees: [0, 5, 0, 0, 5, 5, 0, 9, 2, 7, 0, 7],
    qualities: ['dom7', 'dom7', 'dom7', 'dom7', 'dom7', 'dom7', 'dom7', 'dom7', 'min7', 'dom7', 'dom7', 'dom7'],
    bars: [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1],
    mode: 'major',
    songs: ["Billie's Bounce — Charlie Parker", "Now's the Time — Charlie Parker", 'Tenor Madness — Sonny Rollins'],
    tip: 'A 12-bar blues wearing a suit: bars 8-10 swap the plain V-IV for a VI7 → ii–V turnaround. Hear bar 8 coming and you sound like a jazz player.',
  },
]
