midi-for-ipad-learning

Goal: for each song, the full MIDI plus one MIDI per unique part, white keys only, in iCloud Drive. The user loads them on iPad in midee.app (https://midee.app). midee splits hands itself, so keep both hands in every file.

~/Library/Mobile Documents/com~apple~CloudDocs/golden-brown-midi/
  golden-brown-00-full.mid
  golden-brown-01-riff-bars-1-6.mid        # riff with all its repeats, as in the song
  golden-brown-04-verse-bars-13-20.mid
  ...

<song> is kebab-case. The -midi folder suffix lets the user find the folders.

1. find a piano MIDI on MuseScore

MuseScore has the most piano solo arrangements. curl gets 403 (Cloudflare), so use playwriter (load the playwriter skill first). scripts/musescore.mjs searches and downloads the MIDI without login.

playwriter session new   # then use its id with -s
playwriter -s <id> --timeout 120000 -e '
const m = await import("/Users/morse/.config/opencode/skills/midi-for-ipad-learning/scripts/musescore.mjs")
state.page ??= await context.newPage()
const r = await m.searchMusescore({ page: state.page, query: "golden brown stranglers piano solo" })
console.log(r.slice(0, 10).map(x => (x.official ? "[OFFICIAL] " : "") + x.url + " | " + x.title).join("\n"))'

Pick a result:

• skip [OFFICIAL] scores (paid) and duets, vocal or other instrument versions
• prefer titles with "piano", "piano solo"; "easy" when the user is a beginner
• for ambiguous names, pick the version that fits the other songs (e.g. "Love Story" = Indila)

playwriter -s <id> --timeout 120000 -e '
const m = await import("/Users/morse/.config/opencode/skills/midi-for-ipad-learning/scripts/musescore.mjs")
await m.downloadMusescoreMidi({ page: state.page, url: "https://musescore.com/user/34400169/scores/7209879", outputPath: "/tmp/midi/golden-brown.mid" })'

Fallback: https://freemidi.org (band arrangements, not piano). Page /download3-<id>-<slug>, file /getter-<id> with the page as referer and a cookie jar. bitmidi.com is often down. GitHub code search does not index .mid files.

2. transpose to white keys

uv run /Users/morse/.config/opencode/skills/midi-for-ipad-learning/scripts/white-keys.py /tmp/midi/golden-brown.mid --out /tmp/midi/w/golden-brown.mid

It tries every shift from -6 to +5 semitones and keeps the one with most notes on white keys (C major or A minor). Leftover black keys move one semitone down (G# to G); it prints how many. --no-snap keeps them. Tracks, tempo, time signatures and pedal stay as they are.

3. find the parts

No CLI finds repeated sections in symbolic MIDI (pychorus, allin1 work on audio only), so scripts/parts.py prints the song as text and you choose the parts.

P=/Users/morse/.config/opencode/skills/midi-for-ipad-learning/scripts/parts.py
uv run $P show w/golden-brown.mid --no-notes             # bar letters + repeated runs
uv run $P show w/golden-brown.mid --no-notes --phrase 4  # also 4-bar phrases (try 8 for slow songs)
uv run $P show w/golden-brown.mid --from 9 --to 20       # notes of some bars

labels: A B A B A B A C D D D D E F E~ F~ G G G~ H ...
runs (unit x repeats, bars that do not repeat are grouped):
  bars   1-6   0:00.0  (A B) x3
  bars   9-12  0:17.3  (D) x4
    9 D   6/8 0:17.3 | 1:D2 1.5:A3.D4.F4 2.5:F2 3:A3.D4.F4 3.5:A2 4:G2 5:E2.C4.E4.G4

• bars come from the MIDI time signatures (6/8 and 7/8 changes work)
• same letter = same bar; ~ = small variation (up to 2 notes differ), treat it as the same bar
• (A B) x3 = a loop repeated 3 times (bars 1-6)
• phrases: P2 (~P1) means only 1 bar differs from P1; usually skip it

Choose parts:

1. one part per section: loop, verse, chorus, bridge, outro
2. a loop keeps its repeats, like in the song: cut its longest run. (A B) x3 at bars 1-6 and (A B) x2 at 47-50 gives one part with bars 1-6
3. skip sections that repeat an earlier part, also with small variations
4. name parts by role when clear (riff, verse, chorus, bridge, outro), else part

4. cut and save to iCloud

D=~/Library/Mobile\ Documents/com~apple~CloudDocs/golden-brown-midi
mkdir -p "$D" && cp w/golden-brown.mid "$D/golden-brown-00-full.mid"
uv run $P cut w/golden-brown.mid --out "$D" --name golden-brown \
  --part riff:1-6 --part verse:13-20 --part chorus:37-42 --part outro:51-66

Files are <song>-NN-<part>-bars-<from>-<to>.mid. Each keeps tempo, time signature, key and pedal at its start. cut skips a part whose bar letters equal an earlier part and prints skip ....

5. report

Per song: MuseScore source URL, semitone shift, snapped notes, and the parts list with bars. Remind the user to open the files in midee.app on iPad from the Files app (iCloud Drive).