Commit Graph

7 Commits

Author SHA1 Message Date
83f7affee9 Fix word-wrap scroll jump: visual-line mapping via WrapIndex
Every scroll<->content mapping site (window start, sub-line shift, tap
mapping, max-scroll clamp, selection menu/handle positions) assumed
1 logical line = 1 visual line. When the viewport top crossed the
bottom of a wrapped line, the view jumped past the wrapped remainder
(jump magnitude (count-1)*lh) instead of moving pixel-by-pixel.

- WrapIndex (internal/editor/wrap_index.go): Fenwick tree of
  per-logical-line visual-line counts, parallel to the LineIndex;
  built at index-build time, bookkept by the same
  UpdateLineIndexAfter{Insert,Delete} hooks (never under-stale: every
  touched line resets to the estimate, the next shaping pass
  re-corrects it).
- scrollVisualDecompose: the scroll offset lives in visual-line space:
  k = LineForVisual(floor(s/lh)), r = s - V(k)*lh. All mapping sites
  go through it, so the viewport top is always exactly s into the
  document's visual space (V(k)*lh + r = s) — the jump invariant.
  All-ones index reduces to the legacy 1:1 mapping (pre-shaping and
  non-wrapped behavior unchanged by construction).
- Correction pipeline: the renderer's per-frame VisualLineStarts are
  grouped per logical line and written back (applyWrapCounts). The
  layout feedback now carries the exact window text the layout was
  shaped for (carried in the frame) plus the window start line and the
  content-edit counter; corrections apply only on edit-counter match,
  and grouping over the current window text (wrong after a scroll moved
  the window) is no longer possible.
- bytePosToScreenXY now applies the sub-line shift and the scaled line
  pitch: the selection menu/handles were off by up to a full line.
- maxScroll uses TotalVisuals() with the effective (font-scaled) line
  height; the bottom clamp lands exactly on the file end for wrapped
  content.
- VisibleByteRange returns the real start line (was hardcoded 0).
- emitFrame: replace the unread handoff frame with the newer snapshot
  instead of dropping it — a dropped final frame was never re-emitted
  (emission is event-driven), leaving the consumer one state behind
  forever; fixes the pre-existing TestRealFile_ShiftSelectionInsert
  failure. Still non-blocking.

Tests (mutation-verified where practical): wrap_index_test.go (Fenwick
vs naive model, 3000 ops), wrap_bookkeeping_test.go (edit hooks vs
shadow-string oracle, 400 ops — caught a real m=0 under-marking),
wrap_mapping_test.go (the jump regression: V(k)*lh + r == s over sweeps
+ random offsets; legacy-identity pin; boundary sweep), wrap_apply_test.go
(VisualLineStarts grouping + guards — the first version exposed the
always-true WindowStartByte guard that blocked all post-scroll
corrections). go test -race ./... green.

On-device (emulator, 60 wrapped lines): dp sweep 0/17/50/67/134/340
lands on LINE000-vl0/1/3, LINE001-vl0, LINE002-vl0, LINE005-vl0 —
pixel-exact 1:1, no jump (dp 134 is where the old code jumped to
LINE008); bottom clamp exact.

Docs: architecture.md §6.2 (visual-line space invariant),
development_plan.md (Phase 13), spec.md (wrap + clamp lines).
2026-08-17 19:46:47 -04:00
6c6a0c1a27 Fix write-concurrency race: per-file write protocol + unique temps
The review-identified race: saves are async (owner snapshots content,
worker pool writes), nothing serialized per file, and every write of a
file used the SAME deterministic temp ('.<name>.tmp'). Two overlapping
writes (autosave x autosave, retry x autosave, or the synchronous
FlushAll on GoToBrowser/Shutdown x a worker write) interleaved on the
shared temp and could rename a byte-mixture into place; even without
interleaving, last-rename-wins could promote a STALE snapshot.

Owner-side protocol (logic.go, requestSave + result handler):
- at most one write in flight per file (writeInFlight maps filename ->
  the file version whose content the in-flight write carries);
- a save requested while one is in flight is deferred (savePending) and
  re-issued by the write's result handler with a FRESH snapshot, so
  'last rename wins' coincides with 'newest snapshot wins';
- on success the SNAPSHOT version (not the current one) is recorded as
  written, so an edit that arrived during the write leaves the file
  dirty and triggers the re-issue;
- FlushAll (GoToBrowser, Shutdown) defers via the same protocol instead
  of writing concurrently on the shared temp;
- shutdown drain: on done the owner waits (bounded 5 s) for in-flight
  writes and armed retries to settle before exiting, so the post-exit
  synchronous FlushAll and workerPool.Stop cannot race a straggling
  worker write;
- retry timer now sends a non-blocking token (no timer-goroutine stall
  on a full channel); emitFrame no longer blocks on a slow/gone main
  (frames are snapshots; the next emission wins) - also required so the
  drain can never deadlock on frame delivery.

Mechanism (real/filesystem.go):
- WriteFileAtomic uses a unique per-call temp ('.<name>.tmp.<pid>.<seq>'),
  making same-file staging-file interleaving structurally impossible even
  if the serialization regressed (defense in depth);
- each successful write best-effort removes stale temps of the same file
  (crash leftovers, plus the legacy deterministic name for upgraded
  installs); a failed write removes its own temp.

Tests:
- write_serialization_test.go (e2e): a counting FS wrapper proves the
  peak concurrent same-file saves is 1 across two deliberately
  overlapping autosaves (2 s saves; the second edit lands inside the
  first save's window and its token is deferred, then re-issued with the
  newer content), and that a Flush during an in-flight save adds no
  concurrent writer and the newest snapshot still wins. Mutation-verified:
  disabling the deferral fails it with peak = 2. (The pool's WriteFileTask
  calls FS.WriteFile, not WriteFileAtomic - the real FS is atomic only
  because WriteFile delegates to WriteFileAtomic; the wrapper mirrors that
  delegation or the overlap window does not exist.)
- filesystem_test.go: stale-temp test updated to the new pattern, also
  covering the legacy name and asserting a different file's temp is
  untouched.
- real_file_fuzz_test.go: stray-temp check matches both patterns.

Docs: architecture.md 6.5 rewritten (protocol invariants), spec.md
autosave line, development_plan.md v11 + Phase 12.

On-device smoke: open, type, autosave lands exact content on disk, no
temp files left, clean relaunch. Full suite green under -race.

Residuals (documented): no fsync before rename (power-loss window only);
external-change detection absent; a drain-deadline exit with a straggling
write can only lose freshness (unique temps keep every rename a complete
snapshot).
2026-08-17 16:29:47 -04:00
2a16c0017c Touch selection (v1): long-press/double-tap word selection, drag handles, floating copy/cut/paste menu
Implement the Android-native touch selection model, verified on-device:
- long-press selects the word under the finger (blank -> caret + paste-only
  menu); double-tap selects the word; drag handles resize the selection,
  drag the highlighted body to move it; floating menu offers copy/cut/paste
  (selection) or paste (bare caret), closing on any item tap.
- Renderer reports finger positions (app-local Dp) as tap/double-tap/
  long-press/selection-drag events; the logic goroutine owns all geometry
  (EditorRegion, menu rect, hit-testing, handles) and the renderer only
  draws the frame snapshot.
- Long press: 400 ms still-press on the editor, cancelled by movement
  (non-grabbing raw pointer probe) or by a scroll/handle grab. The main
  loop keeps invalidating while a press is pending (Gio renders on demand;
  a stationary finger produces no frames).
- Clipboard crosses the goroutine boundary via buffered channels
  (clipboardSetChan/pasteReqChan logic->main, pasteChan main->logic);
  main executes the Gio ops and, on Android, invalidates after ReadCmd
  because a queued transfer.DataEvent schedules no frame of its own.

Renderer fixes found while validating on-device:
- clickReg was stored by value in a map; range yielded copies so per-frame
  press bookkeeping (long-press state) was silently discarded. Now pointers.
- On Android a tap's press+release arrive in the same frame and
  gesture.Click/Drag return one event per Update call; without draining
  each gesture's queue every frame the release was lost on an idle window
  and every menu tap was swallowed (needed a second tap to 'rescue' it).
  Click and drag loops now drain to exhaustion (scroll already does).
- pointer.Filter queries must name Kinds: a zero-kinds filter matches
  nothing (the press-probe query was dead).
- Menu.Draw offsets items by the menu origin; the clippable drawElement
  branch registers SelDrag (handles now draw for the TextField).

Tests: internal/editor/touch_selection_test.go (word range, long-press,
double-tap, tap/menu guards, handle drags, menu actions, selection edits)
and internal/test/e2e/touch_selection_e2e_test.go; full suite green under
-race. Docs: spec.md §2.2 + §7, architecture.md §6.3a, development_plan.md
Phases 8-9.
2026-08-17 08:57:55 -04:00
ec11abf8f1 Add text selection, real-file e2e tests, and Android arrow-key support
Selection: shift+arrow extends a selection (absolute byte offsets,
anchor/caret model); insert/backspace/delete replace the selection; the
IME unions its reported range with the active selection; the highlight
is drawn in the TextField and the selection is pushed to the IME.

Android key input (the blocker found during on-device validation):
Gio v0.10 on Android (a) drops modifier state in the JNI bridge and
(b) wraps plain arrow-key presses in input.SystemEvent for focus
navigation, so arrow keys never reached the editor. main.go now
registers explicit named key.Filters for the four arrows (delivers the
press and suppresses the focus jump) and tracks the shift key itself.
Verified on the emulator: plain arrows move the caret, shift+arrow
shows a highlight, typing replaces the selection.

Real-file e2e tests (real on-disk files via the real FileSystem,
multi-chunk 256KB files, chunk-boundary and multi-byte edits) found
and fixed two real bugs:
  1. Line index: UpdateLineIndexAfterEdit only shifted offsets; edits
     involving newlines left it permanently inconsistent. Replaced with
     newline-aware UpdateLineIndexAfterInsert/UpdateLineIndexAfterDelete.
  2. Rune granularity: HandleBackspace/HandleDelete deleted one byte,
     corrupting multi-byte UTF-8 characters (e.g. a 2-byte char
     straddling a chunk boundary). Now rune-granular.

Also: airtight e2e harness load-wait (StatFile/ReadFile/BuildLineIndex
interleaving could satisfy the old condition early).

Full suite green under -race; on-device verified.
2026-08-17 00:32:53 -04:00
be48ad8157 perf: default-off in-app profiler + debug scroll jumps; verify scroll perf & clamping
internal/perf: single-goroutine profiler (no locks). When enabled by the
/storage/emulated/0/PadPerf/enable marker it records one CSV row per logic
frame (seq, ms, frame delta, page, scroll Dp, max-scroll Dp, total lines,
visible byte range), logs a rolling ~1/s summary, and on Stop reports
nearest-rank p50/p90/p99/max. Flushes per row-batch but never fsyncs per
flush (avoids periodic hitches in the logic path).

editor: PerfRecord package-level hook (nil when off) + ProbeRecord;
Logic.emitFrame() now centralizes every frame emission so the profiler sees
each logic frame exactly once, on the owner goroutine. State gains
VisibleStart/VisibleEnd so the probe can confirm shaping stays
viewport-bounded.

logic: optional debug cmd poller (off by default) watches <dir>/cmd as a
one-shot file (top/bottom/frac <0..1>/dp <int>) and the owner applies a
clamped [0,MaxScroll] jump + frame. Enables deterministic large-offset scroll
tests without pixel taps.

main: wires the profiler when the marker file exists; logs present-fps
every 2s; stops the profiler on Destroy.

docs: README package inventory (add internal/perf); architecture §11
profiler facility; spec §5 invariant 7 (scroll always clamped to
[0,maxScroll]) + §6 measured rows; development_plan v5 + Phase 6 results.

Verified: go build/vet + full -race green. On-device 10 MB file:
logic-frame cadence flat across offsets 0.02->1.0 (no large-offset
degradation), visible byte range <=4.3 KB at every offset, clamping exact
across 2->130,955-line files, PSS plateaus ~250 MB (bounded, no leak);
profiler overhead negligible.
2026-08-16 16:53:28 -04:00
d3d11b5d20 Doc: reorganize — delete over-detailed docs, rewrite spec + architecture to match code
- Deleted (drift-prone point-in-time plans / dead specs):
  browser_implementation_plan.md, editor_implementation_plan.md,
  virtual_scroll_render_optimization.md, conflict_resolution.md,
  touch.md, element_model.md, layout_rendering.md, bugs.txt
- Rewrote architecture.md: single-owner/no-lock model, channel topology,
  Frame handoff contract, ownership rules, editor/browser/render internals,
  active vs dead task types, testing hooks.
- Rewrote spec.md: actual behavior (browser, editor, IME, autosave, 50 MB
  limit with measured numbers), actual code layout, invariants to preserve,
  explicit deferred-features table (undo, restoration, sync awareness).
- Added doc/README.md: doc index, documentation policy, build/install
  recipe, on-device observation loop.
- Updated development_plan.md: Phase 5 mostly done; §7 spec deltas written
  with two corrections (no undo at all; no external-change detection).
2026-08-16 13:22:21 -04:00
281298ac1f Add spec.md documentation 2026-05-31 23:21:52 +00:00