Track readable content revisions and durable read cursors in the hub. Acknowledge only rendered foreground tails, persist offline read operations, and preserve newer manual unread choices across devices.
Migrate existing history to a read baseline and cover pagination receipts with shared native conformance fixtures.
Add viewport-driven paging with layout acknowledgements, bounded retries, cancellation gates, and epoch-safe history retention.
Preserve transcript anchors and expansion state, fix tool-group identity collisions, and serialize Android history coordination on Main.
Reduce per-scroll composition and layout work; add native regression tests, CI coverage, and profiling guidance.
HapiProtocol/Window/ — pure port of web/src/lib/message-window-store.ts +
messages.ts, mirroring the Android reference port 1:1:
- MessageWindowState: constants (400/600/800/800/200), MessagePosition,
OlderLoadOutcome, full InternalState fields, persisted v2 snapshot shape
- MessageWindowLogic: every transition (merge/trim preserving queued rows,
latest replace with request-baseline identity preservation, tail sync
begin/apply/finish, older pages + epoch-mismatch reset, enterTailMode
that deliberately keeps requiresLatestReset, activate, SSE ingest with
hidden-row cursor advance, markConsumed stamping server rows to 'sent',
optimistic lifecycle, queued reconcile, hydrate/persist, seededState)
- MessageMerge: position comparator (ASCII tie-break), localId echo
replacement preserving status/invokedAt, 10s sent-dedup fallback
- MessageRetention: calls the fixtures-green chat pipeline's
normalizeDecryptedMessage directly (no hand-mirrored tree to drift)
- WindowMessage: identity-carrying final class (web's !== baseline
classification), tri-state invokedAt, buildOptimisticMessage
HapiClient/Stores/ — async half:
- MessagesProviding seam (three-variant MessagesPageQuery; APIClient
conforms via its existing endpoints)
- MessageWindowController actor: single-flight tail controller with
trailing drain and a synchronous generation bump before the first await
(the web runs to its first suspension; Android used UNDISPATCHED),
fetchOlder with onBeforeApply veto, SSE hooks, optimistic append/status/
cancel-invoked, queued-state reconciliation in 1000-id batches, seedFrom
- WindowSnapshotStore: per-session JSON snapshots, LRU 10 (dedup TODO with
the session-list package's cache) + MessageWindowControllers registry
Tests (swift-testing):
- PaginationFixtureTests: parameterized replay of shared/fixtures/
pagination/*.json against the real controller via a scripted provider;
asserts expectedRequests (canonical JSON incl. explicit-null untils),
expectedOutcome, expectedCandidates, and the final expectedState
projection with per-op labels and first-differing-line diffs
- MessageWindowControllerTests: tail-sync coalescing + trailing drain,
concurrent-SSE preservation across a reset replace, cursor-no-advance
guard, snapshot round-trip/LRU, seedFrom
All 11 fixtures verified green against a line-by-line Python mirror of
these exact algorithms (no local Swift toolchain; CI runs the real suite).
weishu