Previously the action button only said "Downloading…" with no indication of
how far along the transfer was or how fast it was going. With multi-gigabyte
game payloads on a LAN this gave the user no signal whether the download had
stalled, was hitting the wire fast, or was about to finish.
Wire a sampled byte-level progress channel from the download pipeline up to
the action button:
- New `DownloadProgressTracker` in `crates/lanspread-peer/src/download/progress.rs`
holds the total expected bytes plus two atomic counters: `downloaded_bytes`
(deduplicated per `(relative_path, offset)` chunk key, used for the bar) and
`transferred_bytes` (raw cumulative, used for the speed sample). The dedup
prevents a retried chunk from double-counting toward completion while still
letting speed reflect actual wire activity including retry waste, which is
the more useful metric for "is the link doing anything right now?".
- `sample_download_progress` wraps the transfer future, emits an initial 0 B/s
snapshot, then samples on a 500 ms interval (`MissedTickBehavior::Skip` so a
stalled downloader does not generate a thundering herd of catch-up ticks)
and emits one final snapshot when the future resolves, so the UI sees the
closing state before `DownloadGameFilesFinished` arrives.
- New `PeerEvent::DownloadGameFilesProgress(DownloadProgress)` variant carries
`{ id, downloaded_bytes, total_bytes, bytes_per_second }`. The Tauri shell
forwards it as `game-download-progress`; the JSONL harness emits it as
`download-progress`.
- Orchestrator and retry paths refactored to thread a single shared
`Arc<DownloadProgressTracker>` through both the initial transfer and any
retry attempts. New `TransferContext`, `RetryContext`, and `ChunkPlanContext`
structs absorb the parameter-list growth that came with adding the tracker.
Frontend rendering honors the snapshot-is-authoritative decision from commit
`5df82aa` ("fix(ui): derive operation status from snapshots"):
- `Game.download_progress` is an ephemeral overlay carried alongside the card,
not a status field. `mergeGameUpdate` preserves it only while
`install_status === Downloading` and otherwise clears it on the next
snapshot, so the games-list snapshot remains the single authority for when
the bar should disappear.
- The `game-download-progress` listener writes ONLY `download_progress` — it
does not touch `install_status`, `status_message`, or `status_level`. This
preserves the rule that lifecycle events never mutate card status.
- No `game-download-finished` listener; snapshot reconciliation clears the
overlay automatically when status leaves Downloading.
- `ActionButton` renders a percentage fill behind the icon/label via a
`--download-progress` CSS custom property; the existing `.act-busy` spinner
is layered above the fill with `z-index: 1`. `act-downloading` widens the
button to avoid label jitter as the speed number changes (tabular-nums).
- `actionLabel` for the Downloading status now appends a formatted speed
("Downloading… 12.5 MB/s") via the new `formatBytesPerSecond` helper.
Test Plan:
- `just test` — Rust workspace tests including new progress tracker unit tests
(`tracker_counts_only_new_bytes_for_a_retried_chunk`,
`tracker_clamps_reported_bytes_to_total`).
- `just frontend-test` — Deno tests including
`download progress is preserved only while actively downloading` and
`downloading action label includes current speed`.
- `just clippy` — clean.
- Manual: download a multi-GB game from a peer and watch the action button
fill, speed update on the half-second, and reset cleanly on completion.
Refs: download progress visibility, snapshot-authoritative UI architecture
The launcher was mixing lifecycle event handlers with the games-list snapshot
when deciding the card status. That left multiple writers for the same
install_status field and made event ordering visible in React.
Make games-list-updated active_operations the authoritative source for busy
status. Lifecycle events no longer mutate the card status; they only keep their
non-status side effects such as rescans and error messages. The only remaining
optimistic status is CheckingPeers before the backend emits its next snapshot.
Add a frontend reducer test that proves an install stays in Installing while an
active install snapshot exists, then settles to Installed only after the active
operation clears with installed local state.
Test Plan:
- git diff --check
- just fmt
- just frontend-test
- just build
Refs: local install/download status snapshot cleanup
ddidderr
