mpckit/pull-requests/m6-move-copy-swap/m6-move-copy-swap.md

M6: move, copy, swap

Branch: m6-move-copy-swap → main

What changed

Pads can be moved, copied and swapped, across banks:

• Dragging a filled pad onto an empty pad moves it; onto a filled pad swaps the two; holding Alt copies (onto a filled pad: copy and replace). The target cell shows a dashed outline for move/swap and a solid one for copy.
• Dragging over a bank letter switches the grid to that bank, so a pad can be dropped on another bank's pads.
• Move to pad / Copy to pad buttons open a picker (bank and pad, with each pad's sample shown): the keyboard route to the same three actions. Move onto a filled pad becomes Swap, as with dragging.
• Dragging pads inside the window doesn't interfere with dropping WAV files from Explorer: the Wails runtime only handles drags that carry files.

Recorded-notes warning (build plan M6, format doc section 3). Notes point at a slot, not a sample, so they stay where they are. Before any move, swap or copy that changes what a pad with notes will play, a dialog lists each such pad and what its notes will play afterwards. Pads without notes get no dialog. Copying onto a filled pad also asks first. Pads with notes show a notes badge in the grid and a note in the settings panel.

Load (brought forward from M8). M6's done-when needs a project with notes, and only the device makes those, so the app needs Load now. Load opens a .xpj (the name comes from the file, samples from its _[ProjectData] folder) and reports firmware or version warnings. New and Load ask before discarding unsaved changes. M8 keeps missing-file badges, the window-close prompt and the other guard rails.

Go service: MovePad, CopyPad, SwapPads, Load (dialog) and LoadPath. The Dialogs interface gains OpenProject.

Testing

On the server: go vet and go test ./... pass. New service tests cover move/copy/swap across banks (tuning carried, sample shared, move onto a filled pad, out-of-range slot), and Load: cancelled dialog, DemoFile (name, 6 samples, notes on A01–A04 only, preview URL, 2 sequences), and a bad file keeping the current project.

The frontend is untested here (no Node). On the laptop (create C:\temp\m6 first):

1. npm run check in frontend: 0 errors, 0 warnings.
2. wails3 dev, Load testdata\device\DemoFile.xpj. A01–A04 show notes; B01 and B02 don't. Pads play when clicked.
3. Move across banks, with a warning: drag A01 over the C bank letter (the grid switches to bank C) and drop on C01. A dialog says A01 has notes that will play nothing. Cancel: nothing changes. Do it again and confirm: C01 has the kick, A01 is empty.
4. No warning without notes: Alt-drag B01 to bank D, pad D05. It copies with no dialog; B01 is unchanged.
5. Swap: drag A02 onto B02. A dialog lists A02's notes; confirm. A02 and B02 have swapped.

6. Rename to UiMoves, Export to folder C:\temp\m6. Then:

   go run ./cmd/mpckit-cli -load testdata\device\DemoFile.xpj -name CliMoves -out C:\temp\m6 -move "A1:C1" -copy "B1:D5" -swap "A2:B2"
   go run ./tools/xpjdiff C:\temp\m6\UiMoves.xpj C:\temp\m6\CliMoves.xpj
   

   prints identical. (M6 done-when: all three across banks.)

7. Buttons: select C01, Copy to pad → bank A, pad A03 (shows the hat): the button reads "Copy and replace". The warning lists A03's notes. Move to pad onto an empty pad moves it.

8. Unsaved changes: after any edit, New asks to discard; Cancel keeps the project.