The second half: system drag sessions over phase 1's model, per
DRAG-REORDER.md and 04-interactions.md § Drag & drop.
- Card faces, lane headers, and trash rows drag as NSItemProvider sessions
(two exported UTTypes, JSON payload in flatten order, plain-text titles as
the secondary representation) — replacing m4's custom lane-reorder gesture
and trash drag-out wholesale; the app-wide DragSession carries the members,
the frozen dragged sizes, the live proposal, and the effective operation.
- Three drop delegates (lane masonry, strip, window fallback), each accepting
both types and routing internally per the single-target-dispatch rule; the
cursor is the physical mouse converted to strip space; proposals come from
DropSlotMath with hysteresis threaded through, and the lane-strip proposal
clamps in front of the shown trash.
- Locality picks the default — move within a board, copy across, the badge
tracking live; ⌥ forces copy (ignored on within-board lane drags), ⌘
forces move; trash rows restore within their board (positional), copy out
across boards by default, ⌘ forcing the true restore-move.
- N contiguous shadows with reflow keyed on the proposal; the
committed-overlay hold renders the dropped arrangement until the reload
echo lands (1.5 s dissolution deadline for refused writes); the
re-grounding trio: geometry re-derives per render, proposals re-validate
by liveness at release, an emptied drag cancels itself.
- Edge autoscroll (ticking driver over DragAutoScrollMath, re-targeting per
step), the mouse-up-gated late-event cleanup, and the polling watchdog —
the pathfinder's lifecycle traps, ported.
- Store: moveLanes and multi-card restoreByDrag join the one-bracket drop
commits.
784 unit tests.
Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY
The pathfinder's drag-reorder model, ported and generalized (DRAG-REORDER.md
travels with it, rewritten for lanes, the interior masonry, multi-drag,
cross-board sessions, the re-grounding trio, and the committed-overlay hold):
- DropSlotMath — resting-layout zones from analytic lane arithmetic and the
pure masonry placement (MasonryLayout now lays out through the same
MasonryPlacement the drag reads, so geometry cannot drift), span-capped
triggers sized to the dragged run's future footprint, hysteresis holds with
the fresh-entry fallback, boundary ties, own-slot no-ops; nil means hold.
- DragAutoScrollMath — the activation bands and velocity ramp, pure.
- The drop commits, one performWrite bracket each: moveCards/copyCards within
a board (insertion ranks touch only the dragged cards; renumber fallback);
receiveCards/receiveLanes/receiveRestoredCards on the destination store for
cross-board copy and ⌘-move with the import-boundary remint, lane copies
stripping tombstoned cards while moves carry them; restoreByDrag is now
positional, writing order only when the drop names a new one.
Gestures, sessions, previews, and delegates are the second half.
773 unit tests (87 new since the keyboard grammar).
Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY