TODO.md: open work only (closes #235 )

Removes the Completed Steps section: dated accounts of finished work, review and merge history, and notes on past decisions. Git keeps the history. Status, Next Step and Future Steps are unchanged. The Workflow step "move Next Step to the top of Completed Steps" now reads "delete Next Step from `TODO.md`", the standard wording. The `README.md` TODO section no longer calls `TODO.md` the work log; it says the file holds the next step and the steps planned. Model: opus-5-5
Tests pass under heavy host load (closes #233 )
2026-11-11 13:27:23 +00:00 · 2026-11-10 22:55:29 +01:00 · 2026-10-26 19:32:03 +01:00 · 2026-10-26 18:59:28 +01:00 · 2026-10-26 17:48:25 +01:00 · 2026-10-26 11:25:10 +01:00
25 changed files with 2662 additions and 3017 deletions
@@ -2,7 +2,7 @@
 - branch from `next`
 - do the work in Next Step
- move Next Step to the top of Completed Steps
+- delete Next Step from `TODO.md`
 - move the top item of Future Steps into Next Step
 - commit (`TODO.md` changes in the same commit as the work)
 - push
@@ -24,723 +24,6 @@ only sneak has, so it waits on him.
 Tagging and releases are decided by sneak alone, and happen only when he
 declares one.
 # Completed Steps
 - 2026-10-25: `quak files COLLECTION` fetches the files of that collection alone
  (https://git.eeqj.de/sneak/quak/issues/217). It used to wait for a refresh,
  which on an empty cache fetched the files of every collection first. It now
  reads the collection list through `lib.freshCollections()`, then brings that
  one collection up to date through the new `lib.refreshCollection()`. That
  stores and saves its files as a refresh would, and leaves the refresh cursor
  where it was. When the stored copy is current, it asks for none of the files.
  It never runs at the same time as a refresh. Once a refresh has received the
  account's collections, it stores no collection the cache does not hold, and
  `quak files COLLECTION` waits for a refresh instead. A refresh from a cursor
  of 0 replaces all the cache holds, so collections keep the server's order. A
  library opened on a cache that only `lib.refreshCollection()` wrote awaits its
  first refresh. `quak files` with no argument still waits for a refresh. The
  store lists what did not decrypt by collection ID and file ID.
 - 2026-10-22: The JSON `quak backup` and `quak backup-metadata` write for a file
  holds `keywords` in place of the CLIP embedding in its ML data
  (https://git.eeqj.de/sneak/quak/issues/218). The keywords are the titles of
  the Discover categories of Ente's photos app that the file falls in, by the
  app's rule: the cosine similarity of the file's CLIP embedding and the text
  embedding of a category's query is at least the category's minimum score, and
  videos stay out of the categories that leave them out. `src/clip-keywords.ts`
  applies the rule. `src/clip-keyword-vectors.ts` holds the 16 categories with
  their text embeddings. `bin/clip-keyword-vectors` writes it with Ente's CLIP
  text model, and writes the CLIP embedding of a public-domain photo of a sunset
  that the tests use.
 - 2026-10-18: `-v`/`--verbose` raises the CLI's log level once for each repeat,
  and `-q`/`--quiet` prints only fatal errors
  (https://git.eeqj.de/sneak/quak/issues/212). The levels are fatal, error,
  warning, info, debug and trace; the default is info, everything quak printed
  on stderr before, `-v` gives debug and `-vv` trace. `src/cli-log.ts` holds the
  level and the log the commands write stderr lines through. Debug adds each
  retry, which `withRetry` reports through the new `onRetry`, and the start and
  end of each refresh and ML data fetch; trace adds each request, which
  `ApiClient` reports through the new `onRequest`. `--json` no longer keeps the
  progress lines off stderr, so `backup` and `--json` runs log a refresh's
  progress too. Every line that reports a failed file or album is at error,
  which the progress callbacks of `backup`, `backup-metadata` and the thumbnail
  helpers now say, and a command that exits 1 because files or albums failed
  ends with one fatal line saying how many and where to look.
 - 2026-10-18: `quak files` takes the collection ID as an optional argument
  instead of the `--collection` option, which is gone
  (https://git.eeqj.de/sneak/quak/issues/211). With no argument it lists every
  file in the account once, collection by collection; a file in several
  collections is listed with the first of them, which is its `collectionID` in
  `--json`. The fresh read in `src/cli-read.ts` does this.
 - 2026-10-18: Names quak builds from an album name or a title fit in a file name
  (https://git.eeqj.de/sneak/quak/issues/205). `shortenKeepingExtension` in
  `src/filename.ts` cuts a name short to a number of bytes, keeping its
  extension when it fits and always its first character, and can put text right
  before the extension; the backup's `withID` uses it for an ID.
  `defaultFileName` there gives the name a file is saved under when the caller
  gives no path: a prefix such as `thumb_` and the title with unsafe characters
  replaced, cut short with it to 255 bytes, and, for a live photo's image or
  video, with that part's own extension before the cut. `quak get`,
  `quak get-thumb`, `downloadFile` and `downloadThumbnail` use it without
  `--out` or `outPath`. `backup-metadata` cuts an album's name short so that its
  folder, `<id>-<name>`, fits in 255 bytes. `safeExtension` gives `.bin` for an
  extension of more than 16 letters and digits, so a save path's name always
  fits.
 - 2026-10-18: `quak collections` no longer waits for the files of every
  collection (issue 210). On an empty cache it opened its library with a refresh
  that fetched and decrypted the files of each collection in turn, printing
  nothing and storing nothing until all were done, so on a large account it
  seemed to hang. It now reads the collection list alone through the new
  `lib.freshCollections()`, one request that stores nothing. The read commands
  open their library with the new `refreshOnOpen: false`, so each makes only the
  refresh it asks for. A refresh sends a `"progress"` event after each
  collection whose files it fetched, and the commands that wait on one print it
  on stderr, except with `--json`.
 - 2026-10-16: ML data the server sends that does not decrypt, gunzip or parse is
  no longer taken for no ML data (issue 198). `fetchMLDataBatch` returns why for
  each such file beside the payloads; ML data that parses to something other
  than a JSON object, such as `null`, is one of them. The library keeps the
  reasons from its last ML data fetch that succeeded in memory, not in the
  cache, and gives them in `status().mlDataErrors` and in the `fetchMLData`
  event with status `"done"`; a fetch still running or one that fails does not
  change them. `quak backup` writes the reason as `mlDataError` in the file's
  JSON when no ML data is cached for it, and records the file in `failures.json`
  with an error starting `ML data: `; `backup-metadata` writes `mlDataError`
  too. Both exit 1. Tests serve ML data encrypted under a key that is not the
  file's.
 - 2026-10-16: With `--verify`, an original whose hash does not match is no
  longer removed before its replacement is downloaded (issue 199).
  `replaceOriginal` in `src/library/content.ts` downloads the replacement to a
  temporary file beside it, a live photo's image and video each to its own,
  hashes it and renames it over the original only when it matches. When the
  download fails or does not match either, the original keeps its bytes and
  links, and the file goes into `failures.json`. The replacement is always
  downloaded, through the new `fetchOriginal` of the content cache, never copied
  from the cache.
 - 2026-10-16: The `~/bin/quak` that `make install` builds retries a refused
  connection and a name that does not resolve, and the backup records either as
  transient (issue 206). Bun's `fetch` reports them with codes of its own,
  `ConnectionRefused` and `FailedToOpenSocket`, which `src/retry.ts` now counts
  as transport failures. A `POST` or `PUT` is not replayed on them, because bun
  also gives them when it resends a request on a new connection after a
  connection it kept open closed, and the server may already have the request.
  Bun already gave `ECONNRESET` for a reset and a `TimeoutError` for a deadline.
  `classify` in `src/backup.ts` now records any `TimeoutError` as transient, so
  a stalled download, whose error says only that it stalled, is no longer
  `unknown`. The shapes were found by running the binary against local
  listeners.
 - 2026-10-15: An album whose folder or JSON `quak backup` cannot write no longer
  ends the run before the other albums and `failures.json` are written (issue
  197). The run prints `FAILED album <name>: <reason>`, lists the album's ID in
  `failedAlbums` in the result and in `--json`, goes on, and exits 1. An album
  whose folder would have the name of another album's JSON, as `x.json` beside
  `x` would, gets its ID added. A folder or link name over 255 bytes is cut
  short between two characters, by `shortenToBytes` in `src/filename.ts`, and
  gets the ID.
 - 2026-10-15: A network failure is printed and recorded with its reason, not as
  just `fetch failed` (issue 196). `describeError` in `src/errors.ts` gives an
  error's message followed by the message of each error on its `cause` chain,
  such as `fetch failed: connect ECONNREFUSED 1.2.3.4:443`, and each address's
  reason when a host has several and none could be reached. `run` prints that,
  and the backup logs it and records it in `failures.json`, where `classify` now
  calls the failure transient when the chain holds an errno that
  `hasTransportCode` in `src/retry.ts` recognises, for a failed ML data fetch
  too. The walk along the chain moved from `src/retry.ts` to `src/errors.ts`,
  which both use. Tests refuse every connection of a backup, then only one
  file's download, and fail the ML data fetch.
 - 2026-10-15: The README says that `make install` needs nix (issue 200), in
  Getting Started and in "Running the backup from cron": `make build-bin` runs
  bun through `nix-shell -p bun`. The `Makefile` is unchanged.
 - 2026-10-14: `lib.backup()`, and so `quak backup`, works on up to the content
  pool's limit of originals at once, 5 by default, instead of one at a time
  (issue 182). That many workers take files from one shared list, each doing all
  the work for one original, its `--verify` hashing included, so no more
  originals than that are open at once. `BackupLibrary` says the limit as
  `contentConcurrency`. A test holds each download at the fake Ente server to
  count those in flight. Once a worker has thrown, as one does when `onProgress`
  throws, or the lock is lost, no worker takes another file; the backup fails
  once the originals under way are in place, and a lost lock stops it before it
  fetches ML data.
 - 2026-10-14: Next Step said the cache design, issue 36, waits on sneak's
  review, though that issue closed on 2026-10-03 (issue 194). It now names the
  issues open on the tracker.
 - 2026-10-14: A backup whose lock is lost no longer dies with a stack trace
  (issue 184). `lockBackupDirectory` gives proper-lockfile an `onCompromised`
  that records why the lock was lost instead of throwing from its timer, and
  returns the lock, which `quak backup` passes to `lib.backup()` as `lock`. The
  backup then stops before it starts another file with
  `lost the lock on DIR: REASON`, which `quak backup` prints as one line before
  it exits 1. Releasing a lost lock leaves `backup.lock` alone. Tests in
  `test/cli/backup-end-to-end.test.ts` remove the lock, or put another backup's
  in its place, while a download is held open.
 - 2026-10-14: An album or file quak cannot decrypt, or whose metadata is not
  JSON, no longer fails the refresh, so one bad record no longer stops
  `quak backup` from storing anything (issue 181). The refresh leaves it out, an
  album with its files, and the library keeps it with the reason in
  `metadata.json` until the server sends a copy that decrypts or deletes it.
  `quak backup` stores every other file, records each such file in
  `failures.json` with an error starting `could not be decrypted:`, names each
  such album's ID in a printed line, or with `--json` in `undecryptableAlbums`,
  and exits 1 while any remain. A file whose copy in another album decrypts is
  not recorded: its original is stored from that copy, and the album where it
  does not decrypt neither links nor lists it. The read commands answer from
  what decrypted.
 - 2026-10-14: `quak backup` no longer asks the server for changes every 3
  seconds while it runs (issue 183). It opens its library with
  `refreshIntervalSeconds: Infinity`, which the library now takes as no
  background timer, so the backup refreshes only as it starts and no timed
  refresh starts another ML data pass during the run. A test holds a backup's
  download open while two hours pass and counts its `/collections/v2` requests.
 - 2026-10-14: `test/cli/backup-end-to-end.test.ts` runs `quak backup` as cron
  does (issue 186): `backupCommand` and `run`, the real `loadSession` reading a
  session saved after logging in, and every request answered by a fake of the
  Ente HTTP API serving data encrypted with libsodium. It covers the backup tree
  of an account with two albums of its own and one shared with it, a second run
  that downloads nothing, a download that succeeds after two 503s, a 404 that
  lands in `failures.json` with exit 1, a refresh answered 401 with exit 3, and
  `--verify` putting back an original changed on disk. The fake server and the
  account it logs in moved from the backup-metadata test into
  `test/ente-server.ts`, unchanged.
 - 2026-10-14: `files --collection`, `get`, `get-thumb` and
  `helper fix-missing-thumbnails --file` take an ID only when it is written in
  decimal digits and is a safe integer (issue 185). Before, `Number()` read
  `0x10` as 16, `1e3` as 1000 and an empty string as 0, and `--file` dropped an
  ID it could not read without a word. Anything else now prints
  `Invalid file ID: <arg>` or `Invalid collection ID: <arg>` and exits 1 before
  any request; one bad `--file` ID fails the whole command. `parseID` in
  `src/cli-commands.ts` does the check for all four.
 - 2026-10-06: The README says how to run `quak backup` from cron (issue 170):
  log in once as the job's user, a crontab with a backup every night and
  `--verify` on Sundays appending to a log file, and the `HOME` and
  `XDG_DATA_HOME` the job needs to find the saved session. A table gives each
  exit code: 0, the backup is complete; 1, files are in `failures.json` or
  another error stopped the run; 2, another backup of the directory is running;
  3, there is no usable session. The introduction lists everything the backup
  keeps for each file.
 - 2026-10-06: `quak backup --verify` and `lib.backup({ verify: true })` hash
  each original already at its save path as the download check does, streamed, a
  live photo as `<imageHash>:<videoHash>` (issue 168). One that does not match
  the content hash its metadata records is logged, removed (both files of a live
  photo) and put back in the same run, downloaded or copied from the cache, and
  what is put back is hashed too. One that still does not match, or whose
  download fails, goes into `failures.json`. One with no recorded hash is left
  alone. The result, `--json` and the summary gain `verified`, `mismatched` and
  `unchecked`. Without `--verify` nothing is hashed.
 - 2026-10-06: Two backups of the same directory never run at once (issue 169).
  `lib.backup()` takes a lock, `backup.lock` in its download directory, made
  with `proper-lockfile`, before its refresh, and removes it when it ends,
  whether it succeeds or fails. A second backup of the directory, from another
  process or the same one, fails at once with an error naming the directory.
  `quak backup` takes the lock before it opens its library, so a refused run
  sends no request; it prints the error as one line and exits 2. A lock that has
  gone 10 seconds untouched, left by a run that could not remove it, is taken
  over by the next run.
 - 2026-10-06: `quak backup` writes each original's EXIF, XMP and dimensions into
  the file's JSON as `imageMetadata`, what `backup-metadata --exif` records
  (issue 167): for a live photo from its image, for a video nothing, and `{}`
  for an original with none of them. A failed read puts the reason in
  `imageMetadataError` and fails neither the file nor the run. An original is
  read when the run stores it or when its JSON has neither field; otherwise the
  field is taken from that JSON. The hand-built JPEGs moved to
  `test/exif-jpeg.ts`, beside the HEIC.
 - 2026-10-06: When the server answers HTTP 401 and that ends a command that
  loads the saved session, because the server no longer accepts its token, the
  command prints one line,
  `quak: the saved session is no longer valid; run "quak login"`, and exits 3
  (issue 164). `quak backup` meets that 401 on the refresh it starts with,
  before it touches any file. For the same commands, a missing or corrupt
  session file keeps its message and also exits 3, so a cron job can tell that
  the user must log in again. `quak logout` is unchanged. `run` in
  `src/cli-run.ts` recognises the 401, which reaches it unchanged.
 - 2026-10-06: `quak backup` retries a failed request for longer than the other
  commands do (issue 165). `src/retry.ts` exports `UNATTENDED_RETRY_OPTIONS`
  beside the unchanged default: 10 attempts, a 1 s base delay and a 60 s cap, so
  a request that keeps failing waits at most 243 s before it gives up.
  `bin/quak.ts` loads the backup's session with them, so its refresh, ML data
  and downloads all use them. What is retried and the backoff formula are
  unchanged.
 - 2026-10-06: The files this repository copies from `sneak/prompts` are copied
  again from its commit `dd4027b` (issue 171). `.gitignore` and `.dockerignore`
  keep out more secret files, and this repository's build artifacts follow the
  copied content. `script/check` runs `script/fmt-check` again, `script/cibuild`
  runs `script/bootstrap` and `script/check` before the image build,
  `script/fmt` and `script/fmt-check` find the pinned yarn under nvm, and the
  image's last stage marks `/app` safe for git.
 - 2026-10-06: `quak backup` writes the account and album records
  `backup-metadata` writes (issue 166): `account.json` with the account's
  `email` and `userID`, and in each album's JSON its `ownerID`, `isShared`,
  `updationTime` and, when present, its three layers of magic metadata. Each
  file's JSON gains its `updationTime`.
 - 2026-10-05: `quak backup` writes each file's ML data (its faces and CLIP
  embedding) into the file's JSON as `mlData`, the payload
  `lib.mldata.forFile()` returns (issue 163). `lib.backup()` waits for an ML
  data fetch before it writes the JSON files. When that fetch fails, each file
  whose ML data is not cached gets the reason in `mlDataError` and counts as
  failed, and the next run fetches it again.
 - 2026-10-03: The download-albums example test no longer fails on a disk with
  under 50 GiB free (issue 160). It opens its libraries with
  `freeBelowBytes: 0`, so the free space of the disk it runs on cannot shrink
  the cache, evict the original it cached and add a fetch to the count. No other
  test's result depends on that free space. The 50 GiB default is unchanged.
 - 2026-10-02: `docker build .` stamps the commit's tag or short commit, not
  `dev` (issue 154). `script/build` writes the version `script/version` prints
  into `dist/package.json`: the `VERSION` environment variable or build arg when
  one is given, otherwise `git describe --tags --always`, otherwise the version
  `package.json` declares. `.dockerignore` sends `.git`, and a checkout with
  `.git` whose version comes out empty, `dev` or `unknown` fails the build.
  `make build-bin` bundles the built `dist/`, so the single binary reports the
  same version.
 - 2026-10-02: `photo.exif()` returns every EXIF tag in the file as `ExifTags`,
  keyed by tag name, each as exifreader decodes it, not only the thirteen common
  fields (issue 156). The embedded thumbnail's tags are under `Thumbnail`,
  without the thumbnail image. The thirteen typed methods stay, each picking its
  field from the tags `exif()` returns, typed as in `PhotoExif`. The example
  script's JSON files now carry every tag.
 - 2026-10-01: The content cache no longer looks for a live photo that an earlier
  version cached as one ZIP (issue 151). When the cache opens, a live photo's
  file that no JSON file names is now always left alone.
 - 2026-10-01: `examples/download-albums.ts` logs in, opens the library, and for
  every album downloads each photo to its save path, writes the photo's record
  and EXIF fields to a JSON file beside it, and writes the album's photos to
  `albums/<collectionID>.json` (issue 144). The build compiles it to
  `dist/examples/`; the README's "Examples" section says how to run it.
 - 2026-10-01: A `Photo` has one async method for each field of `exif()`, named
  and typed as in `PhotoExif`: `make()`, `model()`, `lensModel()`,
  `dateTimeOriginal()`, `offsetTimeOriginal()`, `exposureTime()`, `fNumber()`,
  `iso()`, `focalLength()`, `orientation()`, `gpsLatitude()`, `gpsLongitude()`
  and `gpsAltitude()` (issue 148). Each calls `exif()` and returns its one
  field, or undefined when the file lacks it. `Photo` implements a type with one
  method per `PhotoExif` field, so the build's type check fails when a field has
  no method. A test checks, on the JPEG and the HEIC, that each method gives the
  same value as `exif()`.
 - 2026-10-01: Each original's save path is
  `YYYY/YYYY-MM/YYYY-MM-DD/YYYY-MM-DD.<fileID>.<ext>` under the library's
  download directory, which defaults to `photos` in the working directory (issue
  143). The date is the photo's `takenAt` in the machine's time zone.
  `photo.savePath` is always a string, with or without a content cache, and
  `isLocal` is true only when the original is at its save path.
  `photo.download()` puts the original there, copied from the cache when the
  cache holds it and fetched otherwise. `lib.backup()` does the same for each
  file, writes each file's JSON beside its original, and links `collections/` to
  the save paths.
 - 2026-10-01: `photo.exif()` and `backup-metadata --exif` read EXIF from
  HEIC/HEIF originals, a live photo's HEIC image included, as well as JPEG and
  the other image formats `exifreader` reads (issue 145). `exifreader` replaces
  `exif-reader` and the JPEG segment scan; `PhotoExif` is unchanged. The `exif`
  field of `backup-metadata --exif` is now exifreader's tag output, and
  `exifRaw` holds the whole EXIF block it could not read. The tests use a real
  HEIC, `test/exif.heic`.
 - 2026-10-01: A `Photo` has `savePath`, `isLocal`, `content()`, `exif()`,
  `modifiedAt`, `hash` and `year` (issue 141). `savePath` is where
  `lib.backup()` writes the original under the library's download directory; for
  a live photo not yet stored, it carries the title's extension, and the backup
  may store the image under a different one. `isLocal` says whether the whole
  original is there. Both look only at the disk. `content()` returns the
  original's bytes and `exif()` the common EXIF fields of a JPEG; both may
  download the original, and `exif()` downloads no video. `PhotoRecord` gains
  `modifiedAt` and `hash`, and the JPEG EXIF scan moved to `src/exif.ts`.
 - 2026-09-29: The "Workflow" list at the top of this file now says to branch
  from `next` and open a pull request that targets `next`, that the repository
  manager squash-merges a reviewed pull request into `next`, and that only sneak
  merges `next` into `main`, as the README does (issue 137).
 - 2026-09-29: The README's "Development workflow" and "For LLMs" sections now
  say work branches from `next`, every pull request targets `next`, the
  repository manager squash-merges reviewed pull requests into `next`, and only
  sneak merges `next` into `main` (issue 135).
 - 2026-09-29: Brought the README and this file in line with `next` after the
  milestone merge (issue 132). The Next Step says no implementation work is open
  and the cache design (issue 36) waits on sneak's review. README corrections:
  the Getting Started comments say when the library refreshes; most, not all,
  Makefile targets call a script; `script/lint` and `script/test` have no host
  path, though `yarn test` does; the SRP handshake uses `fast-srp-hap`, outside
  `crypto/`, and a thumbnail upload's MD5 uses `node:crypto`; the SRP password
  is the first 16 bytes of a 32-byte subkey; the key attributes and token come
  after SRP, after the TOTP code SRP may ask for, or after the email OTP that
  replaces SRP when the account has email MFA on, and quak cannot answer a
  passkey; the auth token is sent as URL-safe base64 with padding; every
  `TypeError` is retried; each download attempt writes its own temporary files,
  two for a live photo, and only the attempt that completes renames them into
  place; `runMetadataBackup` records a failed download in the file's JSON; a
  second `client.logout()` does not throw; `quak logout` with no session exits
  0, and names the cache directory only when it knows it; `login`, `whoami` and
  `logout` open no library; `--exif` records XMP and, for a JPEG, EXIF, and no
  IPTC; which commands take `--json`; a failed ML data request may not have been
  retried; the thumbnail fixer is not limited to baseline JPEG; `quak backup`
  still fetches ML data; a backup's JSON holds the basic metadata fields quak
  keeps and the private and public magic metadata, not every decrypted field,
  and the README no longer lists what the magic metadata holds; the default
  cache directory is the per-user one, not an XDG path on macOS; pinned
  originals can exceed `cacheOriginalsMaxBytes`; which tests cover which
  operations; a default read is only as current as the last refresh whose
  requests all succeeded; `fresh()` and `lib.backup()` join a refresh already
  running; a `Photo` has no `thumbnailPath` or `originalPath`; and `408` and
  `429` are retried.
 - 2026-09-28: Tested the live-photo writer's fsyncs (issue 130). A test checks
  that the image's and the video's temp files are fsynced before either is
  renamed into place, and the directory after both renames, as the `writeAtomic`
  test does for one file.
 - 2026-09-23: Live photos are stored as their image and their video (issue 107).
  A live photo, which Ente stores as one ZIP, is unpacked as it downloads into
  `<fileID>.<ext>` for the image and for the video, each with its extension from
  the ZIP, beside `<fileID>.livephoto.json`, which names the two. Both are
  checked against the recorded hash and renamed into place only when both are
  complete. A ZIP holding a second image or video, or whose two files come to
  more than 20 times its size plus 16 MiB, is refused. The backup and the
  content cache count the live photo as stored only with both files, the album
  folder links both, `quak get` writes both, and the content result gives the
  video as `videoPath`. A ZIP an earlier version stored is replaced on the next
  backup run, and removed from the cache when the library opens it.
 - 2026-09-23: Settled the package metadata (issue 6). quak is not published, so
  `package.json` is marked `"private": true` and the `files` field is gone.
  `engines.node` is `>=22`, the major version `script/bootstrap` and the
  `Dockerfile` use. An `exports` map makes `.` and `./package.json` the only
  importable paths; `runMetadataBackup`, the thumbnail helpers and their types
  stay internal to the CLI.
 - 2026-09-23: Brought the README and this file in line with the tree (issue
  111). The layout lists `src/library/` and the other source files, the backup
  layout names `failures.json` and the optional `thumbnails/`, "Opening a
  library" says what happens when the first refresh fails, the Testing section
  gives the 60-second hard cap and 20-second target for `make test` and names
  the 90-second `timeout` in the `Dockerfile` as the backstop for a hung test,
  and "Tag v1.0.0" is no longer listed as the next step.
 - 2026-09-23: Tested `quak login` and `backup-metadata --exif` (issue 110).
  `loginCommand` takes its login function and its prompts from `CliContext`, and
  `bin/quak.ts` passes `Client.login` and the terminal prompts. Tests cover a
  login from `QUAK_EMAIL` and `QUAK_PASSWORD` with no prompt, the TOTP prompt, a
  failed login, and the saved session's modes, and show that `--exif` and
  `--all` each turn on EXIF extraction and that it is off without them.
 - 2026-09-23: `quak backup` writes each original once and no longer fills the
  cache (issue 106). An original fetched for a backup is written by the download
  writer straight into the backup's `originals/`, and the content cache records
  it there instead of keeping its own copy; one the cache already held is still
  copied. `quak backup` opens its library with the thumbnail and originals
  precache off.
 - 2026-09-23: `backup-metadata`, `helper list-missing-thumbnails` and
  `helper fix-missing-thumbnails` refresh before they answer (issue 100). Each
  awaits `lib.fresh()` before reading, so a file added since the cache was
  written is included, and a failed refresh prints one line and exits 1 instead
  of answering from a stale or empty cache. The README lists them among the
  commands that refresh first.
 - 2026-09-23: `quak backup` waits for the server refresh and fails when it fails
  (issue 99). `lib.backup()` joins a refresh already running or starts one, as
  `fresh()` does, and rejects before touching any file when it fails, leaving
  `failures.json` as it was, so `quak backup` prints the error as one line and
  exits 1 instead of backing up the previous run's file list, or nothing, and
  exiting 0.
 - 2026-09-23: CLI errors print a message instead of a stack trace (issue 102).
  An error a command throws is printed as one `quak: MESSAGE` line on stderr and
  the CLI exits 1 once output has drained. The wrapper that does this moved from
  `bin/quak.ts` to `src/cli-run.ts`, and `bin/quak.ts` now awaits
  `program.parseAsync()`.
 - 2026-09-23: Opening a library no longer deletes another process's download in
  progress (issue 105). The download writer's temp files are named
  `.quak-<pid>-<random>.tmp`, and `removeLeftoverTempFiles`, moved from the
  backup into the download module, deletes a `.quak-*.tmp` file only when the
  process ID in its name is no longer running. The content cache calls it at
  `open()` for `originals/` and `thumbnails/`, the backup as before.
 - 2026-09-23: Re-vendored the lint and test setup from the template (issue 96).
  Linting and testing are the `lint` and `test` phases of the `Dockerfile`;
  `script/lint` and `script/test` each build one with `--no-cache`, and the last
  stage compiles and depends on both, so `script/cibuild` is one build.
  `Dockerfile.lint`, `CHECK_EPOCH`, `LINT_EPOCH` and the tests that checked them
  are gone; `REPO_POLICIES.md` is re-copied.
 - 2026-09-23: Stopped `helper fix-missing-thumbnails` retrying files the server
  always refuses (issue 109). Both thumbnail helpers skip a file another account
  owns without fetching it. The fixer skips a file whose recorded thumbnail size
  is 0 or unknown before downloading it, and otherwise tries smaller encodings
  (720 px quality 50 down to 160 px quality 20) until the encrypted thumbnail is
  no larger than that size, skipping the file if none fits.
 - 2026-09-23: Tested the live-photo hash check's error paths (issue 117). Tests
  download a live photo whose ZIP names an unknown compression method, one whose
  ZIP has no image entry and one with no video entry, and check that nothing is
  stored and the error names the file ID; the unreadable one is not retried.
 - 2026-09-23: `quak logout` ends the session on the server (issue 108). It calls
  `POST /users/logout` through the new `Client.logoutOnServer()`, then deletes
  `session.json` even when that call fails, says so and exits 1. It prints the
  account's cache directory and says it still holds decrypted data. The default
  cache path is now `defaultCacheDirectory()` in the library, shared with
  `Library.open`.
 - 2026-09-23: Fixed the backup's per-collection folders (issue 103). Two files
  in one collection with the same title, and two collections with the same name,
  each get their ID added to the name (`IMG_0001 (12345).JPG`, `Trip (10)/`), so
  none replaces another's symlink or JSON. Each run removes symlinks into
  `originals/` for files no longer in the collection, and the folders of deleted
  or renamed collections, leaving anything else in `collections/` alone. The
  README backup layout states the naming rule.
 - 2026-09-23: Checked downloaded originals against their recorded content hash
  (issue 68). `downloadFile`, which `quak get`, the content cache and backup all
  use, hashes the decrypted bytes (unkeyed BLAKE2b-512, standard base64) and
  stores nothing on a mismatch, failing with an error naming the file ID. A live
  photo ZIP is unpacked as it streams with `fflate` and its image and video
  hashed separately as `<imageHash>:<videoHash>`. `decryptFile` reads older
  clients' `imageHash` and `videoHash` fields for live photos. A file with no
  recorded hash is stored unchecked.
 - 2026-09-23: Kept one account's cache from mixing with another's (issue 104).
  When `metadata.json` in the cache directory was written for a different,
  non-zero user ID than the client's, `Library.open` deletes it and `mldata/`
  and starts empty, so the first refresh enumerates from 0. This only happens
  with `--cache-dir` or an explicit `cacheDirectory`; the default path already
  includes the user ID. A test opens one account's cache as another account.
 - 2026-09-23: `backup-metadata` no longer stops on one failed ML data request
  (issue 101). Each request of up to 200 files is tried on its own; a failed one
  is logged, its files are written with the reason in `mlDataError`, and the
  command exits 1 once the dump is complete. `fetchMLData`, which only this
  command used, is gone; the command calls `fetchMLDataBatch` per batch.
 - 2026-09-23: Single-sourced the version string (issue 5). `package.json` is the
  only place it is written: `src/index.ts` imports it for `VERSION` and
  `bin/quak.ts` passes `VERSION` to commander. tsc copies `package.json` to
  `dist/package.json`, so the import resolves from the built output too, and
  `script/build` runs the built CLI with `--version` to prove it. A test checks
  that `VERSION` and `quak --version` both equal the `package.json` version.
 - 2026-09-23: Tested that `Library.close()` waits for the originals precache
  (issue 93). The test that holds a precache fetch open while `close()` runs now
  runs once with only the thumbnail fill and once with only the originals fill,
  so dropping either wait from `Precache.close()` fails a test.
 - 2026-09-23: Fixed two intermittently failing library tests (issue 90).
  `Library.close()` now returns a promise that resolves once an in-flight
  refresh (including its cache write), the ML data fetch and running precache
  sweeps have finished; the library tests await it, so `afterEach` no longer
  removes the cache directory while something is still writing into it. The
  precache test waits for both fills to report "done" instead of for its stub
  source to be called, which happened before the cache recorded the file.
 - 2026-09-23: Pinned three guards reviewers found untested (issue 89). The
  download idle deadline's timer is unref'd, so it can never keep the process
  alive, and a test checks no timer is left after a download completes or fails.
  A test covers the rejection of `#` in a request path. The EXIF scan compares
  the `Exif` header only in an APP1 segment of length 8 or more, so it never
  reads the next segment's bytes, with a test for a short one.
 - 2026-09-23: Made the download deadline an idle deadline (issue 24).
  `downloadTimeoutMs` now aborts a file or thumbnail download only after no
  bytes have arrived for that long, default 60 seconds, instead of bounding the
  whole transfer at 10 minutes, so a slow download that keeps making progress
  completes. A download that fails before reading the whole body cancels it, so
  a failed file no longer holds its connection.
 - 2026-09-23: Every `ApiClient` request URL is now built by one function next to
  the class (issue 18), so a self-hosted `apiOrigin` with a base path keeps it
  on every request, a path works with or without a leading slash, and query
  parameters are percent-encoded. A path containing `?` or `#` is rejected with
  an error instead of being silently cut.
 - 2026-09-23: Made the CLI testable and tested it (issue 12). The command bodies
  moved from `bin/quak.ts` into `src/cli-commands.ts` as functions that take
  their options and a context (output streams, session directory, cache
  directory, session loader) and return an exit code; `bin/quak.ts` only wires
  them to commander and exits with the code once stdout and stderr have drained,
  so nothing below it calls `process.exit`. `test/cli/commands.test.ts` drives
  them with a fake client: session file modes, logout, the missing and corrupt
  session paths, and the output and exit code of `whoami`, `collections`,
  `files`, `get`, `get-thumb`, `backup` and `helper list-missing-thumbnails`.
 - 2026-09-23: Hardened the backup tree's atomic copy (issue 22). `copyAtomic`
  fsyncs its temp file before the rename and the directory after it, through the
  download writer's `fsyncPath`; each backup run deletes `.quak-backup-*.tmp`
  files whose process is no longer running. The README backup layout names the
  temp files and states that the rename replaces a symlink and takes the temp
  file's permissions. Added tests for a missing and an unwritable destination
  directory for `downloadFile` and `downloadThumbnail`.
 - 2026-09-23: Hardened the JPEG EXIF scan behind `backup-metadata --exif` (issue
  11). Every segment length is checked against the remaining bytes and lengths
  under 2 stop the scan, so a truncated or corrupt original can neither throw
  nor loop. A malformed or unparseable EXIF segment is recorded as
  `imageMetadata.exifError`, and a failure to read the original as
  `imageMetadataError` in the per-file JSON, instead of the field being left
  out.
 - 2026-09-22: Hardened the retry classifier (issue 80). A `POST` or `PUT` is
  replayed only when every errno in the cause chain is a connect errno, and it
  no longer follows redirects. `getRetryOptions()` returns a copy. Tests pin
  every errno the classifier names, the cause-chain depth limit, cycle
  termination, and a fresh deadline per attempt for every retrying entry point.
  The README's endpoint list is the one place that names the requests the replay
  rule covers.
 - 2026-09-22: Stopped `make test` collecting tests from checkouts nested under
  `.claude/` (issue 25). vitest ignores `.gitignore` when finding tests, so a
  nested checkout ran the whole suite again; `vitest.config.ts` now adds
  `.claude/**` to vitest's default excludes, and
  `test/packaging/nested-checkout.test.ts` plants a nested checkout in a temp
  directory and fails if vitest would collect it.
 - 2026-09-22: Dropped the deprecated `@types/libsodium-wrappers-sumo` stub from
  `devDependencies` (issue 27). It shipped no declarations; the types come from
  `libsodium-wrappers-sumo` itself. `yarn.lock` regenerated by `yarn remove`.
 - 2026-09-22: Hardened the client session lifecycle (issue 10).
  `Client.fromJSON` checks every snapshot field and each key's decoded length
  and names the bad field; `toJSON` reads the token through
  `ApiClient.getAuthToken` and throws when there is none; `logout` zeroes the
  key buffers, and `collectionsSince` re-checks for logout after its request so
  it never decrypts with zeroed keys. The CLI reports a corrupt session file
  separately from a missing one (`src/cli-session.ts`).
 - 2026-09-22: Sanitized file names taken from server metadata (issue 9). A new
  `src/filename.ts` holds the one sanitizer, used by `quak get`/`get-thumb`
  without `--out`, `downloadFile`/`downloadThumbnail` without `outPath`, and the
  backup and metadata backup trees; it removes separators, control characters,
  leading dots and Windows device names, and falls back to a name built from the
  ID for an empty title. Originals-cache extensions are letters and digits only,
  else `.bin`. A user-supplied path is used as is. `decryptFile` reads a missing
  or non-string title as "" and rejects metadata that is not a JSON object.
 - 2026-09-22: Rewrote the README API reference (and the Getting Started / usage
  snippets) to match the shipped cache/API library on `next` (issue 53, issue
  13). Documented `Library.open` and its options, the default-read vs `fresh()`
  distinction (and that the CLI's read commands are fresh), the record types and
  `snapshot()`/`subscribe()`, the `albums`/`photos`/`timeline` read surface,
  `Photo` content methods, `thumbnails.ensure`, the `mldata` search surface,
  `backup()`, the three request pools (10/5/25), and the on-disk cache layout;
  noted the deferred content-hash integrity check (issue 68). Docs-only; no code
  changed.
 - 2026-09-22: Added resumable, deletion-aware enumeration to `Client` (issue 38,
  closes issue 7). `collectionsSince`/`filesSince` take a starting cursor,
  decrypt live records, surface tombstoned ids in a separate `deleted` list (a
  tombstone has nothing to decrypt, so it is a bare id, not a hollow record),
  and return the max `updationTime` seen as the cursor to resume from.
  `filesSince` refuses to loop when the diff reports `hasMore` without advancing
  the cursor (issue 7). `listCollections`/`listFiles` are now thin wrappers that
  enumerate from `sinceTime: 0` and drop deletions, so existing callers are
  unaffected.
 - 2026-09-22: Carried file size, thumbnail size, and the deletion flag through
  `decryptFile` (issue 37, foundation for the cache/API design). Live files now
  populate `file.size`/`thumbnail.size` from the server's `info` (left
  `undefined` when the server omits it), and `isDeleted` is carried from the
  diff row onto `EnteFile`. No caller change: `listFiles` still filters deleted
  rows before decrypting. Surfacing a tombstone through decryption belongs to
  the enumeration unit (issue 38).
 - 2026-08-10: Made `lint-once.test.ts` enforce what its header claims. It walked
  `make check` only, so it never read `Dockerfile` — the image CI builds through
  `script/cibuild` — and a second `prettier --check .` could be added there with
  the suite staying green. The walk now also starts at
  `.gitea/workflows/check.yml` and follows its `run:` steps, so the graph under
  test is the one CI executes rather than the one someone assumed it executes.
  The lockfile assertion was a substring check against the whole of
  `script/bootstrap`, which has two install sites and so reported the branch the
  containers never take; the two branches are now resolved separately and every
  `yarn install` in each is required to be `--frozen-lockfile`. Prettier is
  counted per occurrence instead of per line, so two invocations chained with
  `&&` no longer read as one, and edges are followed on counted lines instead of
  being skipped. Every way for the walk to reach nothing — an unknown target, an
  unknown script, a missing file, a node with no commands, an unknown node kind
  — is a thrown error rather than a quiet zero. Every assertion in the file was
  mutation-tested individually.
 - 2026-08-10: Stopped `make check` running `prettier --check .` twice. Since
  linting moved into Docker, the duplicate was one container pass and one host
  pass of the same check: `script/lint` builds `Dockerfile.lint`, which runs
  prettier as a build step, and `script/check` then called `script/fmt-check` as
  well. The host call is gone from `script/check` and from `script/precommit`;
  the container keeps checking formatting, because a successful
  `Dockerfile.lint` build is what CI treats as proof of a clean tree, and it is
  also what still fails the pre-commit hook on a badly formatted tree.
  `script/fmt-check` survives as a standalone entrypoint, whose verdict cannot
  drift from the container's. A test walks the invocation graph from each
  entrypoint — through the Makefile shims, the `script/` calls and the
  `docker build` — and asserts the prettier count, so the duplication cannot
  come back unnoticed.
 - 2026-08-10: Moved all linting into Docker. `script/lint` builds a new root
  `Dockerfile.lint`, which copies the repo into the digest-pinned node image and
  runs eslint and prettier as build steps, so a successful build is a clean
  lint; no host lint path remains and `yarn lint` is gone from `package.json`. A
  fail-closed `LINT_EPOCH` guard stops Docker serving the linter layers from
  cache, which is how a lint build returns success in under a second having
  linted nothing. The lint stage inside `Dockerfile` and its `COPY --from=lint`
  ordering hack are gone: that image now runs `make test` and `make build` only,
  because `script/check` calls `script/lint` and running it in a container would
  mean docker inside docker. `script/cibuild` builds the lint image first, then
  the test and build image.
 - 2026-08-09: Made `make docker` green and policy-conformant. Multi-stage
  Dockerfile: a lint stage runs `make fmt-check` and `make lint`, and the check
  stage takes a `COPY --from=lint` dependency on it before running `make check`
  and `make build`. `CHECK_EPOCH` and a fail-closed guard stop Docker serving
  those two layers from cache, which is what let a build report success without
  running the suite. `script/projectname` says `quak`, so the image is tagged
  `quak`; `script/bootstrap` updates apt lists before installing, so a Debian
  base works; `.dockerignore` no longer ships the compiled binary, the caches or
  agent worktrees into the build context, and keeps `.gitignore` in it for
  prettier.
 - 2026-08-09: Fixed the TypeScript build. `rootDir` is the repo root, so `bin/`
  compiles alongside `src/` instead of failing with TS6059; output is
  `dist/src/` and `dist/bin/`, which is where `main`, `types` and `bin.quak` now
  point. `script/build` verifies the declared entrypoints exist after the
  compiler runs and makes the CLI executable, the Dockerfile runs `make build`
  as well as `make check`, and a `quak` script makes the README's
  `yarn quak <command>` examples work.
 - 2026-08-09: Retry policy: no retry on 4xx (except `408` and `429`),
  exponential backoff with full jitter on 5xx, transport failures and truncated
  transfers, under per-attempt deadlines that cover the response body as well as
  the request. Downloads retry request, stream consumption and decryption as one
  unit; `postJSON` and `putJSON` are replayed only when the connection was never
  established.
 - 2026-08-09: Downloads verify the secretstream terminated on `TAG_FINAL` and
  write output atomically: a truncated body is rejected instead of landing on
  disk as a short file, and plaintext is staged in a sibling temp file and
  renamed into place, so a failed download leaves the destination untouched.
 - 2026-07-07 Adopted scripts-to-rule-them-all: `script/` entrypoints, Makefile
  shims, README Entrypoints section
 - 2026-06-10: Decrypted collections shared by other users (sealed-box keys);
  listCollections drops deleted-collection tombstones.
 - 2026-06-10: Login hardening: dual-2FA empty-string fields handled, TOTP
  preferred when a passkey is also enrolled, interactive input via
  @inquirer/prompts.
 - 2026-06-10: Replaced sharp with pure JS (jpeg-js + exif-reader); added
  single-binary bun build and make install.
 - 2026-06-09: Added backup-metadata command (ML data always included, --exif
  opt-in); rewrote README to match the implementation; added thumbnail helper
  tests.
 - 2026-05-13: Full CLI surface: login, backup with dedup symlink layout,
  collections, files, get, get-thumb, thumbnail repair helpers.
 - 2026-05-13: Client OO API with literate usage tests; file download and
  decryption; all three metadata layers decrypted and persisted; renamed quack
  to quak.
 - 2026-05-11: SRP login flow (email OTP + TOTP) and ApiClient.
 # Future Steps
 - Future desktop client, separate repo:
@@ -37,9 +37,16 @@ import {
    thumbnailName,
 } from "./cli-output.js";
 import { type Log, logRefresh } from "./cli-log.js";
-import { freshCollections, freshFiles, freshFile } from "./cli-read.js";
+import {
    cachedFilesByID,
    freshCollections,
    freshFiles,
    freshFile,
    freshFilesByID,
 } from "./cli-read.js";
 import { withExtension } from "./filename.js";
 import { runMetadataBackup } from "./metadata-backup.js";
 import type { Collection, EnteFile } from "./model/types.js";
 import { listMissingThumbnails, fixMissingThumbnails } from "./thumbnails.js";
 export interface CliContext {
@@ -130,12 +137,13 @@ const readLibraryClient = (client: Client): LibraryClient => ({
 // Open a library for a single point command. The aggressive background
 // precache (issue #48) is off, because a one-shot `collections` or `get` must
-// not start downloading the whole account. No refresh starts as it opens or on
+// not start downloading the whole account. No refresh starts as the library
-// a timer. Each command asks for the refresh it needs. `collections` needs none
+// opens or on a timer. Each command asks for the refresh it needs.
-// (issue #210). `files COLLECTION` needs one only when `refreshCollection()`
+// `collections` and `files` with a collection ID need none (issues #210 and
-// resolves to `false` (issue #217). While a refresh runs,
+// #217). Nor do `get` and `get-thumb` on an empty cache (issue #222). Nor does
-// each collection whose files it has fetched is logged, so a large account
+// `helper fix-missing-thumbnails --file` on an empty cache (issue #223). While
-// shows progress rather than nothing.
+// a refresh runs, each collection whose files it has fetched is logged, so a
 // large account shows progress rather than nothing.
 const openReadLibrary = (ctx: CliContext, client: Client): Promise<Library> =>
    Library.open({
        client: readLibraryClient(client),
@@ -284,11 +292,11 @@ export const filesCommand = async (
    const lib = await openReadLibrary(ctx, client);
    try {
-        // Force a server round-trip and list in enumeration order (issue #36
+        // Ask the server for current state (issue #36 amendment, issue #52).
-        // amendment, issue #52). Each file prints from its own decrypted
+        // Each file prints from its own decrypted metadata (raw title,
-        // metadata (raw title, microsecond creationTime) via cli-output, and in
+        // microsecond creationTime) via cli-output. The files print in the
-        // the pre-library CLI's enumeration order, not the projection's
+        // order `freshFiles` returns them, not the projection's newest-first
-        // newest-first order.
+        // order.
        const files = await freshFiles(lib, collectionID);
        if (!files) {
            ctx.log("fatal", `Collection ${collectionID} not found`);
@@ -325,14 +333,13 @@ export const getCommand = async (
    try {
        // Force a server round-trip so the file resolves against current state
        // (issue #36 amendment, issue #52).
-        const resolved = await freshFile(lib, fileID);
+        const file = await freshFile(lib, fileID);
-        if (!resolved) {
+        if (!file) {
            ctx.log("fatal", `File ${fileID} not found`);
            return 1;
        }
        const { photo, file } = resolved;
-        const result = await photo.original();
+        const result = await lib.originalOf(file);
        // Default name is the file's own title, as the pre-library CLI used
        // (not the editedName-preferring projection title) (issue #52).
        if (result.videoPath === undefined) {
@@ -383,14 +390,13 @@ export const getThumbCommand = async (
    try {
        // Force a server round-trip so the file resolves against current state
        // (issue #36 amendment, issue #52).
-        const resolved = await freshFile(lib, fileID);
+        const file = await freshFile(lib, fileID);
-        if (!resolved) {
+        if (!file) {
            ctx.log("fatal", `File ${fileID} not found`);
            return 1;
        }
        const { photo, file } = resolved;
-        const result = await photo.thumbnail();
+        const result = await lib.thumbnailOf(file);
        // Default name is thumb_<file's own title>, as the pre-library CLI
        // used (not the projection title) (issue #52).
        const outPath = opts.out ?? thumbnailName(file);
@@ -567,10 +573,13 @@ export const fixMissingThumbnailsCommand = async (
    }
    const lib = await openReadLibrary(ctx, client);
    try {
-        // Refresh first so files added since the cache was written are found;
+        let found: Map<number, { file: EnteFile; collection: Collection }>;
-        // a failed refresh throws.
+        if (fileIDs.length > 0) {
            found = await freshFilesByID(lib, fileIDs);
        } else {
            // Refresh first so files added since the cache was written are
            // checked; a failed refresh throws.
            await lib.fresh();
        if (fileIDs.length === 0) {
            ctx.log("info", "Scanning for missing thumbnails...");
            const missing = await listMissingThumbnails(
                lib,
@@ -583,12 +592,14 @@ export const fixMissingThumbnailsCommand = async (
                return 0;
            }
            ctx.log("info", `Found ${fileIDs.length} file(s) to fix.`);
            found = cachedFilesByID(lib, fileIDs);
        }
        const results = await fixMissingThumbnails(
            lib,
            client,
            fileIDs,
            found,
            (msg, level) => ctx.log(level ?? "info", msg),
        );
@@ -1,15 +1,18 @@
 // The CLI's log level, and the one function the commands write stderr lines
 // through.
 //
-// Every line quak prints on stderr is a log line at one of six levels, from
+// Every line quak logs goes to stderr, at one of six levels, from the
-// the quietest: fatal, error, warning, info, debug, trace. A run prints the
+// quietest: fatal, error, warning, info, debug, trace. A run prints the lines
-// lines at its own level and at every quieter one. Its level is info unless
+// at its own level and at every quieter one. Its level is info unless `-v` or
-// `-v` or `-q` asks for another (see "CLI surface" in the README). Every
+// `-q` asks for another (see "What quak prints" in the README). A command that
-// command that exits non-zero logs a fatal line saying why, so even `-q`, which
+// runs and exits non-zero logs a fatal line saying why, so even `-q`, which
-// prints only fatal lines, never leaves a non-zero exit unexplained. An error
+// prints only fatal lines, never leaves such an exit unexplained. An error
 // line reports something that failed, such as a file or an album, and a
 // warning something that did not fail but needs the user's attention. stdout
-// carries only a command's output and is not a log.
+// carries a command's output and the prompts of `login`, and is not a log.
 // Two things on stderr are not log lines: the `error:` message for a
 // command line that quak cannot parse, and the usage printed when no command
 // is given.
 //
 // The library itself writes no lines: its layers report through callbacks, and
 // the CLI logs what they report. `logRequests` gives the API client options
@@ -2,47 +2,40 @@
 //
 // `collections`, `files`, `get`, and `get-thumb` must answer for
 // the account's state at the moment the command runs, not for whatever the
-// local cache last happened to hold (owner amendment, issue #36). `files`
+// local cache last happened to hold (owner amendment, issue #36). `get`,
-// without a collection ID, `get` and `get-thumb` therefore force a server
+// `get-thumb` and `files` without a collection ID therefore force a server
-// round-trip through `Library.fresh()`, and only then read. A collection, file,
+// round-trip through `Library.fresh()` and only then read, so a change made
-// or metadata change made elsewhere is then visible. `collections` asks the
+// elsewhere is visible. `collections` asks the library for the collection list
-// library for the collection list alone through `Library.freshCollections()`
+// alone through `Library.freshCollections()` (issue #210): a refresh would also
-// (issue #210). A refresh would also fetch the files of every collection, which
+// fetch the files of every collection, which on a large account takes long and
-// `collections` does not print, and on a large account that takes long.
+// which `collections` does not print. `files` with a collection ID reads that
-// `files COLLECTION` reads the collection list the same way, for the same
+// list too, then that one collection's files through `Library.freshFiles()`
-// reason. It then brings that one collection up to date through
+// (issue #217). On an empty cache, `get` and `get-thumb` read that list, then
-// `Library.refreshCollection()` (issue #217), and fetches no other collection's
+// one collection's files at a time, until they find the file (issue #222).
-// files. Once a refresh has received the account's collections,
+// `helper fix-missing-thumbnails --file` does the same until it finds every
-// `refreshCollection()` stores no collection the library does not hold.
+// file it names (issue #223).
 // `files COLLECTION` then forces a refresh instead.
 //
-// `collections` lists in the server's order. `files` lists in the library's
+// `collections` and `files` with a collection ID list in the server's order.
-// own enumeration order: `listCollections()`, then `listFiles()` for each.
+// `files` without one lists in the library's own enumeration order
-// Those are the orders the pre-library CLI printed. The `albums`/`photos`
+// (`listFiles()`). Neither command uses the `albums`/`photos` projection's
-// projection would re-sort the rows newest first. After a refresh, the
+// newest-first order, which re-sorts the rows. The field values still come
-// library holds collections in the order the server first sent them. The
+// from each record's raw metadata via `cli-output.ts`. `files` without a
-// field values still come from each record's raw metadata via
+// collection ID lists every file in the account once (issue #211): the library
-// `cli-output.ts`. `files` without a collection ID lists every file in the
+// keeps a record of a file for each collection that holds it, and only the
-// account once (issue #211).
+// first collection's record is listed.
 // The library keeps a record of a file for each collection that holds it, and
 // only the first collection's record is listed.
 import type { Collection, EnteFile } from "./model/types.js";
 import type { Photo, PhotosAPI } from "./library/index.js";
 // The slice of `Library` these helpers read. `Library` satisfies it
-// structurally. A test can drive them with a stand-in that records the
+// structurally; a test can drive them with a stand-in that records each fresh
-// `fresh()`, `freshCollections()` and `refreshCollection()` calls. The
+// read and serves records in a known enumeration order.
 // stand-in serves records in a known enumeration order.
 export interface FreshReadLibrary {
    fresh(): Promise<unknown>;
    freshCollections(): Promise<Collection[]>;
-    refreshCollection(collection: Collection): Promise<boolean>;
+    freshFiles(collection: Collection): Promise<EnteFile[]>;
    getCollection(id: number): Collection | undefined;
    listCollections(): Collection[];
    listFiles(collectionID: number): EnteFile[];
    getFileByID(fileID: number): EnteFile | undefined;
    photos: Pick<PhotosAPI, "byID">;
 }
 // Every live collection, current as of one collections request, in the
@@ -51,14 +44,11 @@ export const freshCollections = (
    lib: FreshReadLibrary,
 ): Promise<Collection[]> => lib.freshCollections();
-// The files of one collection, in enumeration order. `undefined` (not an empty
+// The files of one collection, as the server holds them now, in the server's
-// list) when the collection does not exist, so the caller can tell "no such
+// order. `undefined` (not an empty list) when the collection does not exist, so
-// collection" from "an empty collection". They are current as of one
+// the caller can tell "no such collection" from "an empty collection". Without
-// collections request and the requests that bring that collection alone up to
+// a collection ID, every file in the account as of a forced refresh, each once,
-// date. When `refreshCollection()` resolves to `false`, they are current as of
+// as held by the first collection that holds it.
 // a forced refresh instead. Without a collection ID, every file in the account,
 // current as of a forced refresh. Each file is listed once, as held by the
 // first collection that holds it.
 export const freshFiles = async (
    lib: FreshReadLibrary,
    collectionID?: number,
@@ -66,12 +56,7 @@ export const freshFiles = async (
    if (collectionID !== undefined) {
        const collections = await lib.freshCollections();
        const collection = collections.find((c) => c.id === collectionID);
-        if (!collection) return undefined;
+        return collection ? lib.freshFiles(collection) : undefined;
        if (!(await lib.refreshCollection(collection))) {
            await lib.fresh();
            if (!lib.getCollection(collectionID)) return undefined;
        }
        return lib.listFiles(collectionID);
    }
    await lib.fresh();
    const listed = new Set<number>();
@@ -86,16 +71,80 @@ export const freshFiles = async (
    return files;
 };
-// One file, current as of a forced refresh, resolved to both its content
+// One file as the server holds it now, or `undefined` when no collection holds
-// handle (`Photo`, for fetching bytes) and its raw record (`EnteFile`, for the
+// it. When the cache holds the account's collections, it refreshes and looks
-// default output name and field values). `undefined` when the file is unknown.
+// the file up in the cache. On an empty cache, it reads the collection list,
 // then one collection's files at a time, and stops at the first collection
 // that holds the file. That search stores nothing.
 export const freshFile = async (
    lib: FreshReadLibrary,
    fileID: number,
-): Promise<{ photo: Photo; file: EnteFile } | undefined> => {
+): Promise<EnteFile | undefined> => {
    // Only a refresh stores collections, so a cache holding any holds them all.
    if (lib.listCollections().length > 0) {
        await lib.fresh();
-    const photo = lib.photos.byID({ fileID });
+        return lib.getFileByID(fileID);
-    const file = lib.getFileByID(fileID);
+    }
-    if (!photo || !file) return undefined;
+    for (const collection of await lib.freshCollections()) {
-    return { photo, file };
+        const files = await lib.freshFiles(collection);
        const file = files.find((f) => f.id === fileID);
        if (file) return file;
    }
    return undefined;
 };
 // The most recently updated collection first, and the higher ID first on a
 // tie. `Library.albums.list()` lists albums in this order.
 const byNewestCollection = (a: Collection, b: Collection): number =>
    b.updationTime - a.updationTime || b.id - a.id;
 // Each file named by `fileIDs` that the cache holds, mapped to its record and
 // the collection it was found in. Collections are searched in
 // `byNewestCollection` order, and a file is found in the first that holds it.
 // So `helper fix-missing-thumbnails` names a file after the same album as
 // `helper list-missing-thumbnails`. It reads the cache alone, so the caller
 // refreshes first.
 export const cachedFilesByID = (
    lib: FreshReadLibrary,
    fileIDs: number[],
 ): Map<number, { file: EnteFile; collection: Collection }> => {
    const wanted = new Set(fileIDs);
    const found = new Map<number, { file: EnteFile; collection: Collection }>();
    const collections = [...lib.listCollections()].sort(byNewestCollection);
    for (const collection of collections) {
        for (const file of lib.listFiles(collection.id)) {
            if (wanted.has(file.id) && !found.has(file.id)) {
                found.set(file.id, { file, collection });
            }
        }
    }
    return found;
 };
 // Each file named by `fileIDs` as the server holds it now, mapped to its record
 // and collection as `cachedFilesByID` maps it. When the cache holds the
 // account's collections, it refreshes and looks the files up in the cache. On
 // an empty cache, it reads the collection list, then one collection's files at
 // a time, and stops once it has found every file. That search stores nothing.
 export const freshFilesByID = async (
    lib: FreshReadLibrary,
    fileIDs: number[],
 ): Promise<Map<number, { file: EnteFile; collection: Collection }>> => {
    // Only a refresh stores collections, so a cache holding any holds them all.
    if (lib.listCollections().length > 0) {
        await lib.fresh();
        return cachedFilesByID(lib, fileIDs);
    }
    const wanted = new Set(fileIDs);
    const found = new Map<number, { file: EnteFile; collection: Collection }>();
    const collections = await lib.freshCollections();
    for (const collection of [...collections].sort(byNewestCollection)) {
        if (found.size === wanted.size) break;
        for (const file of await lib.freshFiles(collection)) {
            if (wanted.has(file.id) && !found.has(file.id)) {
                found.set(file.id, { file, collection });
            }
        }
    }
    return found;
 };
@@ -581,14 +581,34 @@ export class ContentCache implements PhotoContent, ThumbnailsAPI {
        fileID: number,
        opts?: ContentOptions,
    ): Promise<ContentResult> {
-        return this.get(fileID, "original", "on-demand", opts?.onProgress);
+        const file = this.fileOrThrow(fileID);
        return this.get(file, "original", "on-demand", opts?.onProgress);
    }
    async thumbnail(
        fileID: number,
        opts?: ContentOptions,
    ): Promise<ContentResult> {
-        return this.get(fileID, "thumbnail", "on-demand", opts?.onProgress);
+        const file = this.fileOrThrow(fileID);
        return this.get(file, "thumbnail", "on-demand", opts?.onProgress);
    }
    // The original of `file`, fetched and cached as `original` does. `file` is
    // used as given, so `getFile` need not know it.
    async originalOf(
        file: EnteFile,
        opts?: ContentOptions,
    ): Promise<ContentResult> {
        return this.get(file, "original", "on-demand", opts?.onProgress);
    }
    // The thumbnail of `file`, fetched and cached as `thumbnail` does. `file`
    // is used as given, so `getFile` need not know it.
    async thumbnailOf(
        file: EnteFile,
        opts?: ContentOptions,
    ): Promise<ContentResult> {
        return this.get(file, "thumbnail", "on-demand", opts?.onProgress);
    }
    // Put the original at the save path of `file` under the download directory
@@ -615,7 +635,7 @@ export class ContentCache implements PhotoContent, ThumbnailsAPI {
        destination: string,
    ): Promise<ContentResult> {
        const result = await this.acquire(
-            fileID,
+            this.fileOrThrow(fileID),
            "original",
            "on-demand",
            undefined,
@@ -638,8 +658,7 @@ export class ContentCache implements PhotoContent, ThumbnailsAPI {
        fileID: number,
        destination: string,
    ): Promise<{ path: string; videoPath?: string }> {
-        const file = this.getFile(fileID);
+        const file = this.fileOrThrow(fileID);
        if (!file) throw new Error(`content cache: unknown file ${fileID}`);
        return this.pools.content.run(
            async () => {
                const fetched = await this.fetchInto(
@@ -721,7 +740,8 @@ export class ContentCache implements PhotoContent, ThumbnailsAPI {
        onProgress: ((event: EnsureEvent) => void) | undefined,
    ): Promise<EnsureResult> {
        try {
-            const result = await this.acquire(fileID, kind, priority, signal);
+            const file = this.fileOrThrow(fileID);
            const result = await this.acquire(file, kind, priority, signal);
            const status = result.cached ? "skipped" : "done";
            onProgress?.({ fileID, status, path: result.path });
            return { fileID, path: result.path };
@@ -736,8 +756,16 @@ export class ContentCache implements PhotoContent, ThumbnailsAPI {
        }
    }
    // The record `getFile` gives for `fileID`. It throws for a file `getFile`
    // does not know.
    private fileOrThrow(fileID: number): EnteFile {
        const file = this.getFile(fileID);
        if (!file) throw new Error(`content cache: unknown file ${fileID}`);
        return file;
    }
    private async get(
-        fileID: number,
+        file: EnteFile,
        kind: Kind,
        priority: Priority,
        onProgress: ((event: ContentEvent) => void) | undefined,
@@ -745,7 +773,7 @@ export class ContentCache implements PhotoContent, ThumbnailsAPI {
        const onByte: ProgressCallback | undefined = onProgress
            ? (bytesDone) => onProgress({ status: "downloading", bytesDone })
            : undefined;
-        const result = await this.acquire(fileID, kind, priority, undefined, {
+        const result = await this.acquire(file, kind, priority, undefined, {
            onByte,
        });
        onProgress?.(
@@ -767,7 +795,7 @@ export class ContentCache implements PhotoContent, ThumbnailsAPI {
    // photo's original is present only with its video, and is returned with
    // it.
    private async acquire(
-        fileID: number,
+        file: EnteFile,
        kind: Kind,
        priority: Priority,
        signal: AbortSignal | undefined,
@@ -778,8 +806,7 @@ export class ContentCache implements PhotoContent, ThumbnailsAPI {
        videoPath?: string;
        cached: boolean;
    }> {
-        const file = this.getFile(fileID);
+        const fileID = file.id;
        if (!file) throw new Error(`content cache: unknown file ${fileID}`);
        const isLivePhoto =
            kind === "original" && file.metadata.fileType === "livePhoto";
@@ -1,37 +1,29 @@
 // The library surface over the local cache.
 //
 // `Library.open()` loads the on-disk metadata store (issue #41), then starts
-// the refresh loop. When the stored cursor is 0, `open()` awaits the first
+// the refresh loop. When the cache loaded empty it awaits the first refresh,
-// refresh. No refresh has then stored any collection: the cache is empty, or
+// so the library never opens onto an empty store it could have filled; when an
-// holds only what `refreshCollection()` stored. The library must not serve
+// existing copy loaded, that first refresh runs in the background and `open()`
-// that as the whole account. Otherwise that first refresh runs in the
+// returns as soon as the cached data is ready to serve — a slow or unreachable
-// background. `open()` returns as soon as the cached data is ready to serve,
+// server no longer stalls opening. A background timer then refreshes every
-// so a slow or unreachable server does not stall opening. A background timer
+// `refreshIntervalSeconds`. Every default read is answered from RAM — no
-// then takes a turn `refreshIntervalSeconds` after its last turn ends. Each
+// default read touches the network. There is deliberately no `sync()`, no
-// turn starts a refresh, unless a refresh or `refreshCollection()` is already
+// `refresh()`, no `serverReachable` flag, and no "before each read" mode
-// running. Every default read is answered from RAM — no default read touches
+// (design #36).
 // the network. There is deliberately no `sync()`, no `refresh()`, no
 // `serverReachable` flag, and no "before each read" mode (design #36).
 //
-// `fresh()` is an exception (issue #75, an owner amendment to #36). It awaits
+// `fresh()` is the one exception (issue #75, an owner amendment to #36): it
-// a refresh, and only then hands back the read namespaces. A caller that needs
+// forces a refresh, awaits it, and only then hands back the read namespaces, so
-// server-current data uses it. Concurrent `fresh()` calls coalesce onto one
+// a caller that needs server-current data can ask for it. Concurrent `fresh()`
-// in-flight refresh. A refresh that fails rejects the caller. The default
+// calls coalesce onto one in-flight refresh, and a refresh that fails rejects
-// reads stay silent and serve the last good copy. The default methods and the
+// the caller (the default reads stay silent and serve the last good copy). The
-// background loop are unchanged.
+// default methods and the background loop are unchanged.
 //
 // `freshCollections()` is the fresh read of the collection list alone (issue
-// #210). It sends one collections request and stores nothing.
+// #210): one collections request, no collection's files, and nothing stored,
-// `quak collections` uses it. `refreshCollection()` brings one collection
+// for a caller such as `quak collections` that needs no more. `freshFiles()`
-// from that list up to date in the store (issue #217). It fetches that
+// is the fresh read of one collection's files, and stores nothing either
-// collection's files alone, as a refresh would. `quak files COLLECTION` uses
+// (issue #217). A caller that asks for each refresh it needs can also open the
-// it. It never runs at the same time as a refresh. Once the stored cursor is
+// library with `refreshOnOpen: false`, so that `open()` starts none.
 // past 0, it only updates a collection the store holds, and only a refresh
 // adds one. A refresh from a stored cursor of 0 replaces all the store holds.
 // So after a refresh, the store holds collections in the order the server
 // first sent them. A caller that asks for
 // each refresh it needs can also open the library with `refreshOnOpen: false`,
 // so that `open()` starts none.
 //
 // A refresh reports through `onProgress` each collection whose files it has
 // fetched, so a large account, whose first refresh fetches the files of every
@@ -40,12 +32,10 @@
 // A refresh stages all of its network work first and only mutates the store
 // once every fetch has succeeded. A refresh that fails partway therefore never
 // becomes visible to reads: the last good snapshot stays in place, and the
-// failure surfaces through `onProgress` and `status()` instead. A save can
+// failure surfaces through `onProgress` and `status()` instead. A commit that
-// still fail after the store has changed in RAM. The store then stays marked
+// mutates RAM but then fails to persist keeps `status().lastError` set and the
-// unsaved until a later save lands. Until then, every `commit()` retries the
+// store marked unsaved until a later save actually lands, so a stuck disk is
-// save. A refresh whose save fails sets `status().lastError`, which stays set
+// never masked by a subsequent empty refresh.
 // until a later refresh succeeds. `refreshCollection()` never sets or clears
 // it. So a stuck disk is never hidden by a later refresh that changes nothing.
 import { rm } from "node:fs/promises";
 import { join, resolve } from "node:path";
@@ -76,6 +66,8 @@ import {
    ContentCache,
    savePath,
    storedAtSavePath,
    type ContentOptions,
    type ContentResult,
    type ContentSource,
    type ThumbnailsAPI,
    type EnsureOptions,
@@ -170,23 +162,21 @@ export interface LibraryClient {
        payloads: Map<number, MLData>;
        errors: Map<number, unknown>;
    }>;
-    // The byte source for the on-disk content cache. Optional, so a mock
+    // The byte source for the on-disk content cache. Optional so a mock client
-    // client that only serves metadata still satisfies the interface. Without
+    // that only serves metadata still satisfies the interface; when absent (and
-    // it, and with no `contentSource` passed to `open`, the content cache is
+    // no explicit `contentSource` is passed to `open`) the content cache is
-    // disabled. `Photo.original`/`thumbnail` and `thumbnails.ensure` then
+    // disabled and `Photo.original`/`thumbnail` and `thumbnails.ensure` throw.
    // throw.
    contentSource?(): ContentSource;
 }
-// A progress event for one unit of background work. A metadata "refresh" and
+// A progress event for one unit of background work. A metadata "refresh" or an
-// an ML "fetchMLData" pass each fire "started" before their network work. Each
+// ML "fetchMLData" pass each fire "started" before their network work and then
-// then fires exactly one of "done" or "failed". A "failed" event carries the
+// exactly one of "done" or "failed"; "failed" carries the error message and
-// error message. An ML "done" reports in `fetched` how many payloads it
+// an ML "done" reports how many payloads it stored and, in `mlDataErrors`,
-// stored. Its `mlDataErrors` lists each file whose ML data did not decrypt,
+// each file whose ML data did not decrypt, gunzip or parse, with the reason.
-// gunzip or parse, with the reason. In between, a refresh fires "progress"
+// In between, a refresh fires "progress" after each collection whose files it
-// after each collection whose files it fetched. Its `fetched` is how many
+// fetched: `fetched` is how many collections it has fetched the files of so
-// collections it has fetched the files of so far, and `total` how many it
+// far, `total` how many it will. The precache fills
 // will. The precache fills
 // ("precacheThumbnails"/"precacheOriginals", #48) fire "started"/"done" around
 // each sweep that has work, "done" reporting the count newly cached.
 export interface RefreshEvent {
@@ -214,10 +204,9 @@ export interface LibraryOptions {
    // directory at open. The content cache treats an original already stored
    // at its save path as present.
    downloadDirectory?: string;
-    // How long after its last turn ends the background timer takes the next.
+    // How long after one refresh ends the background timer starts the next.
-    // A turn starts a refresh unless a refresh or `refreshCollection()` is
+    // `Infinity` starts none: the library then refreshes only as it opens and
-    // running. With `Infinity` the timer takes no turn: the library then
+    // when `fresh()` or `backup()` asks.
    // refreshes only as it opens and when `fresh()` or `backup()` asks.
    refreshIntervalSeconds?: number;
    // Whether `open()` starts a refresh. Defaults to true. With false, `open()`
    // returns at once onto what the cache holds, empty or not, and a refresh
@@ -256,9 +245,8 @@ export interface LibraryStatus {
    // Wall-clock ms of the last refresh that succeeded, or undefined if none
    // has yet.
    lastRefreshAt?: number;
-    // The error of the most recent refresh, set only when it failed. The next
+    // The message from the most recent refresh, set only while that refresh
-    // refresh that succeeds clears it. `refreshCollection()` never sets or
+    // failed; cleared by the next success.
    // clears it.
    lastError?: string;
    // Wall-clock ms of the last ML fetch pass that succeeded, or undefined if
    // none has yet (or ML fetching is disabled).
@@ -321,17 +309,12 @@ export class Library {
    private readonly precache?: Precache;
    private timer?: ReturnType<typeof setTimeout>;
-    // The in-flight refresh cycle or `refreshCollection()`, or undefined when
+    // The in-flight refresh cycle, or undefined when none runs. One slot serves
-    // neither runs. One slot holds both, so they never run at the same time.
+    // both paths: the background loop skips when it is set, and a fresh read
-    // The background loop skips while it is set. A fresh read (issue #75)
+    // (issue #75) coalesces onto it or starts one. The promise carries the
-    // coalesces onto a running refresh. It waits for a running
+    // cycle's real outcome (it rejects on failure); the background loop ignores
-    // `refreshCollection()` to end, and then joins or starts a refresh. The
+    // that, a fresh read propagates it.
    // promise carries the real outcome: it rejects on failure. The background
    // loop ignores a failure. A fresh read passes on the failure of the
    // refresh it joins or starts, and `refreshCollection()` passes on its own.
    private cycle?: Promise<void>;
    // Whether `cycle` is a refresh cycle rather than a `refreshCollection()`.
    private cycleIsRefresh = false;
    // Guards the ML fetch pass so a slow backfill never runs twice at once; a
    // refresh whose pass is still running kicks nothing new. Holds the running
    // pass, so `close()` and `backup()` can wait for it. It rejects when the
@@ -344,20 +327,19 @@ export class Library {
    private lastMLError?: string;
    // For each file whose ML data the last ML fetch pass that succeeded got
    // but could not decrypt, gunzip or parse, why not, by fileID. A pass
-    // gathers its own and puts them here only when it ends without failing.
+    // gathers its own and puts them here when it ends without failing, so
-    // So `status()` and `backup()` never see the list of a pass still running
+    // `status()` and `backup()` never see the list of a pass that is still
-    // or one that failed. Kept in RAM only, never in the cache.
+    // running or that failed. Kept in RAM only, never in the cache.
    private mlDataErrors = new Map<number, unknown>();
-    // The plain-record projection as of the last store change, and the GUI
+    // The plain-record projection as of the last refresh, and the GUI change
-    // change subscribers. A refresh or `refreshCollection()` that alters the
+    // subscribers. A refresh that alters the projection notifies each with the
-    // projection notifies each subscriber with the delta. `lastRecords`
+    // delta; `lastRecords` is kept current every refresh so a subscriber that
-    // advances on each `commit()` that changes the store. A subscriber that
+    // joins later diffs against the state its own `snapshot()` already returned.
    // joins later then diffs against the state its own `snapshot()` returned.
    private readonly subscribers = new Set<(change: LibraryChange) => void>();
    private lastRecords: DerivedRecords;
    // RAM holds changes disk has not yet accepted (an earlier save failed).
-    // Cleared only when a save succeeds. Until then, every `commit()` retries
+    // Cleared only when a save actually succeeds; keeps the store trying to
-    // the save.
+    // persist and the failure visible in `status()` until then.
    private unsaved = false;
    private constructor(args: {
@@ -387,7 +369,7 @@ export class Library {
        this.lastRecords = this.deriveNow();
        // The read namespaces derive fresh from the store on each call, so they
-        // always reflect what it holds now.
+        // always reflect the latest refresh.
        const derive = (): DerivedRecords => this.deriveNow();
        const root = this.downloadDirectory;
        const saves: SavePathLookup = {
@@ -414,16 +396,14 @@ export class Library {
        this.mldata = makeMLDataAPI(() => this.mlStore);
    }
-    // Load the cache and start the refresh loop. When the stored cursor is 0,
+    // Load the cache and start the refresh loop. With an empty cache the first
-    // the first refresh is awaited. Such a cache is empty, or holds only what
+    // refresh is awaited, so `open()` resolves onto populated data whenever the
-    // `refreshCollection()` stored. `open()` then resolves onto the whole
+    // server is reachable; that awaited refresh may still fail, and the library
-    // account whenever the server is reachable. If that refresh fails, the
+    // then opens empty with the failure recorded in `status()`. With an
-    // library opens onto what the cache holds, with the failure recorded in
+    // existing cache the first refresh runs in the background and `open()`
-    // `status()`. With any other cache the first refresh runs in the
+    // returns as soon as the cached data is ready — an unreachable server does
-    // background, and `open()` returns as soon as the cached data is ready.
+    // not block opening. With `refreshOnOpen: false` there is no first
-    // An unreachable server then does not block opening. With
+    // refresh: `open()` returns onto the cache as it is.
    // `refreshOnOpen: false` there is no first refresh: `open()` returns onto
    // the cache as it is.
    static async open(opts: LibraryOptions): Promise<Library> {
        const { userID } = opts.client.whoami();
        const cacheDirectory =
@@ -439,8 +419,8 @@ export class Library {
        let store = await MetadataStore.load(metadataPath);
        // A cache directory given explicitly can hold another account's cache.
        // Its records and cursor are not this account's, so delete it and the
-        // ML data beside it and start empty. A user ID of 0 means nothing was
+        // ML data beside it and start empty. A user ID of 0 means the cache
-        // ever stored there, so there is nothing to discard.
+        // was never refreshed and so holds nothing to discard.
        if (store.userID !== 0 && store.userID !== userID) {
            await rm(metadataPath, { force: true });
            await rm(join(cacheDirectory, "mldata"), {
@@ -463,11 +443,10 @@ export class Library {
            ? await MLDataStore.open(join(cacheDirectory, "mldata"))
            : undefined;
-        // Build the content cache from an explicit source or the client's own.
+        // Build the content cache from an explicit source or the client's own,
-        // Take its record of what is already cached, and reap orphan temp
+        // and take its record of what is already cached (and reap orphan temp
-        // files, before the first projection. Cached paths are then present
+        // files) before the first projection, so cached paths are present from
-        // from the start, and the first `commit()` raises no spurious
+        // the start and the first refresh raises no spurious path-change diff.
        // path-change diff.
        const source = opts.contentSource ?? opts.client.contentSource?.();
        let cache: ContentCache | undefined;
        let precache: Precache | undefined;
@@ -521,26 +500,22 @@ export class Library {
            precache,
        });
-        // Start filling from whatever the loaded store already holds. Each
+        // Start filling from whatever the loaded store already holds; each
-        // later `commit()` re-kicks the fills with its new files, and retries
+        // refresh below re-kicks with the new files (and retries any that
-        // any that failed. An empty store starts empty here, and fills once a
+        // failed). An empty store starts empty here and fills after its first
-        // `commit()` stores files.
+        // refresh.
        precache?.start();
        if (opts.refreshOnOpen === false) {
            // The caller asks for each refresh it needs.
            lib.scheduleNext();
-        } else if (store.collectionsSinceTime > 0) {
+        } else if (store.loadedFromDisk) {
-            // The stored cursor has moved, so a refresh has stored the
+            // An existing copy already answers reads; refresh in the background
-            // account's collections and the cache's copy answers reads.
+            // and start the interval once that first cycle settles.
            // Refresh in the background, and start the interval once that
            // first cycle settles.
            void lib.runRefresh().then(() => lib.scheduleNext());
        } else {
-            // The stored cursor is still 0, so no refresh has stored any
+            // Nothing was cached: wait for the first refresh to fill the store
-            // collection: the cache is empty, or holds only what
+            // (or fail) rather than resolve onto an empty library.
            // `refreshCollection()` stored. Wait for the first refresh to fill
            // the store (or fail) rather than resolve onto part of the account.
            await lib.runRefresh();
            lib.scheduleNext();
        }
@@ -578,9 +553,9 @@ export class Library {
        return snapshotFrom(this.deriveNow(), Date.now());
    }
-    // Deliver a `LibraryChange` whenever a refresh or `refreshCollection()`
+    // Deliver a `LibraryChange` whenever a refresh alters the projection. A
-    // alters the projection. One that changes nothing delivers nothing. The
+    // refresh that changes nothing delivers nothing. The returned handle's
-    // returned handle's `unsubscribe` stops delivery.
+    // `unsubscribe` stops delivery.
    subscribe(args: { onChange: (change: LibraryChange) => void }): {
        unsubscribe: () => void;
    } {
@@ -623,13 +598,12 @@ export class Library {
        };
    }
-    // Fresh reads (issue #75, owner amendment to design #36). Wait for a
+    // Fresh reads (issue #75, owner amendment to design #36). Force a refresh,
-    // refresh to complete and persist, then hand back the same
+    // wait for it to complete and persist, then hand back the same
-    // `albums`/`photos`/`timeline` namespaces. They then reflect a completed
+    // `albums`/`photos`/`timeline` namespaces — now guaranteed to reflect a
-    // server round-trip. A running `refreshCollection()` is waited for first.
+    // completed server round-trip. Concurrent calls coalesce onto one refresh;
-    // Concurrent calls coalesce onto one refresh. A refresh that fails rejects
+    // a refresh that fails rejects here, where the default namespaces would
-    // here, where the default namespaces would stay silent and serve the last
+    // instead stay silent and serve the last good copy.
    // good copy.
    async fresh(): Promise<FreshReads> {
        await this.refreshNow();
        return {
@@ -642,10 +616,10 @@ export class Library {
    // The fresh read of the collection list alone (issue #210): every live
    // collection that decrypts, in the server's order, from one collections
    // request. Unlike a refresh, it fetches no collection's files, which on a
-    // large account take long. It stores nothing. A refresh from a stored
+    // large account take long. Nothing is stored: a refresh fetches a
-    // cursor past 0 fetches a collection's files only when the collection is
+    // collection's files only when the collection is new or has changed since
-    // new or has changed since the stored copy. So does `refreshCollection()`.
+    // the stored copy, so a collection stored here without its files would
-    // Neither would fetch the files of a collection stored here without them.
+    // never have them fetched.
    async freshCollections(): Promise<Collection[]> {
        if (this.closed) throw new Error("the library is closed");
        const { collections } = await this.client.collectionsSince({
@@ -654,44 +628,67 @@ export class Library {
        return collections;
    }
-    // Bring one collection up to date in the store (issue #217), given its
+    // The fresh read of one collection's files (issue #217): every live file
-    // record from `freshCollections()`. It does for that collection what a
+    // in it that decrypts, in the server's order. `collection` is a record
-    // refresh does for a changed one. It fetches no other collection's files.
+    // `freshCollections()` returned, whose key decrypts the files. It fetches
-    // It resolves to whether the store then holds the collection.
+    // no other collection's files. Like `freshCollections()`, it stores
-    //
+    // nothing. It returns each file once, as the latest copy the server sent,
-    // It adds a collection the store does not hold only while the stored
+    // where the first copy was.
-    // cursor is 0, before any refresh has received a collection. After that,
+    async freshFiles(collection: Collection): Promise<EnteFile[]> {
    // it stores nothing for such a collection and resolves to false. Only a
    // refresh may then add it, after the collections the store holds.
    //
    // It runs in the same slot as a refresh, so the two never run at the same
    // time. It first waits for a running refresh or `refreshCollection()` to
    // end. While its own work runs, a fresh read or `backup()` waits for it,
    // and the background loop skips its turn.
    async refreshCollection(collection: Collection): Promise<boolean> {
        while (this.cycle) await this.cycle.catch(() => {});
        if (this.closed) throw new Error("the library is closed");
-        let held = false;
+        const { files } = await this.client.filesSince({
-        await this.startCycle(false, async () => {
+            collectionID: collection.id,
-            held = await this.refreshCollectionOnce(collection);
+            collectionKey: collection.key,
            sinceTime: 0,
        });
-        return held;
+        const byID = new Map<number, EnteFile>();
        for (const file of files) byID.set(file.id, file);
        return [...byID.values()];
    }
    // The original of `file`, fetched and cached as `Photo.original()` does.
    // `file` is used as given, so the store need not hold it. On an empty
    // cache, `quak get` passes a file that `freshFiles()` returned.
    async originalOf(
        file: EnteFile,
        opts?: ContentOptions,
    ): Promise<ContentResult> {
        if (!this.cache) {
            throw new Error(
                "originalOf requires a library opened with a content cache",
            );
        }
        return this.cache.originalOf(file, opts);
    }
    // The thumbnail of `file`, fetched and cached as `Photo.thumbnail()` does.
    // `file` is used as given, so the store need not hold it. On an empty
    // cache, `quak get-thumb` passes a file that `freshFiles()` returned.
    async thumbnailOf(
        file: EnteFile,
        opts?: ContentOptions,
    ): Promise<ContentResult> {
        if (!this.cache) {
            throw new Error(
                "thumbnailOf requires a library opened with a content cache",
            );
        }
        return this.cache.thumbnailOf(file, opts);
    }
    // Back up every in-scope file to `opts.downloadDirectory`, or else the
    // library's, each original at its save path, with a durable failure
-    // ledger (issue #51). It first takes the lock in that directory, unless
+    // ledger (issue #51). Takes the lock in that directory first, unless the
-    // the caller passes the lock it took as `opts.lock`. Taking it fails at
+    // caller passes the lock it took as `opts.lock`, failing at once while
-    // once while another backup of that directory runs. Once the lock is lost,
+    // another backup of it runs, and before it starts another file once the
-    // the backup fails before it starts another file (see
+    // lock is lost (see `lockBackupDirectory`). Waits for a
-    // `lockBackupDirectory`). It waits for a completed refresh as `fresh()`
+    // completed refresh, as `fresh()` does, joining one already running, and
-    // does, joining one already running. When that refresh fails, it rejects
+    // rejects before touching any file but the lock when it fails. Then puts
-    // before touching any file but the lock. It then puts pending originals
+    // pending originals at their save paths as `Photo.download()` does (and
-    // at their save paths as `Photo.download()` does, through the content
+    // optional thumbnails) through the content cache and pools, waits for an
-    // cache and pools. With `includeThumbnails` it also fetches thumbnails. It
+    // ML data fetch, and rebuilds the derived symlink/JSON views from the
-    // waits for an ML data fetch. It rebuilds the derived symlink/JSON views
+    // model, each file's JSON with its ML data, beside an `account.json` with
-    // from the model, each file's JSON with its ML data. An `account.json`
+    // the account's email and user ID.
    // beside them holds the account's email and user ID.
    // Throws before any network work when no content cache backs the
    // originals it must fetch.
    backup(opts?: BackupOptions): Promise<BackupResult> {
@@ -728,15 +725,12 @@ export class Library {
        );
    }
-    // Stop the background timer. Idempotent. A refresh or `refreshCollection()`
+    // Stop the background timer. Idempotent. An in-flight refresh is left to
-    // in flight is left to finish, and nothing starts after it. The returned
+    // finish; it will not schedule another cycle once closed. The returned
-    // promise resolves once all of these have finished:
+    // promise resolves once that refresh (including its cache write), the ML
-    //  - that refresh or `refreshCollection()`, with its cache write;
+    // fetch pass and the precache fetches already running have all finished,
-    //  - the ML fetch pass;
+    // so a caller can then remove the cache directory. A refresh failure is
-    //  - the precache fetches already running.
+    // reported through `status()`, not thrown here.
    // A caller can then remove the cache directory. A refresh failure is
    // reported through `status()`, and a `refreshCollection()` failure to its
    // own caller. Neither is thrown here.
    async close(): Promise<void> {
        this.closed = true;
        const precacheClosed = this.precache?.close();
@@ -759,41 +753,33 @@ export class Library {
        this.timer.unref?.();
    }
-    // The background loop's refresh: run a cycle unless a refresh or
+    // The background loop's refresh: run a cycle unless one is already in flight
-    // `refreshCollection()` is in flight (or the library is closed), and never
+    // (or the library is closed), and never let a failure escape — the
-    // let a failure escape. The background path reports errors through
+    // background path reports errors through `status()`/`onProgress`, it does
-    // `status()`/`onProgress`; it does not throw. It resolves once the cycle
+    // not throw. Resolves once the cycle it started (or skipped past) settles.
    // it started settles, or at once when it starts none.
    private runRefresh(): Promise<void> {
        if (this.closed || this.cycle) return Promise.resolve();
-        return this.startCycle(true, () => this.refreshCycle()).catch(() => {});
+        return this.startCycle().catch(() => {});
    }
-    // A fresh read's refresh (issue #75): join the running refresh or start
+    // A fresh read's refresh (issue #75): force a cycle and await it, rejecting
-    // one, and await it, rejecting if it fails. Concurrent fresh reads
+    // if it fails. Concurrent fresh reads coalesce onto the one in-flight cycle
-    // coalesce onto the one in-flight cycle — the background loop's included —
+    // — the background loop's included — so they never fan out into redundant
-    // so they never fan out into redundant server round-trips. A running
+    // server round-trips.
-    // `refreshCollection()` is waited for first.
+    private refreshNow(): Promise<void> {
-    private async refreshNow(): Promise<void> {
+        if (this.closed) {
-        while (this.cycle && !this.cycleIsRefresh) {
+            return Promise.reject(new Error("the library is closed"));
            await this.cycle.catch(() => {});
        }
-        if (this.closed) throw new Error("the library is closed");
+        return this.cycle ?? this.startCycle();
        return this.cycle ?? this.startCycle(true, () => this.refreshCycle());
    }
-    // Start `work` and record it in the in-flight slot, so every other caller
+    // Start one refresh cycle and record it as the in-flight cycle so every
-    // sees it. `isRefresh` says whether it is a refresh cycle, which a fresh
+    // caller coalesces onto it. The returned promise carries the cycle's real
-    // read can coalesce onto. The returned promise carries the real outcome.
+    // outcome; each caller attaches the handling its own path needs, and the
-    // Each caller attaches the handling its own path needs, and the slot is
+    // slot is cleared once the cycle settles.
-    // cleared once the work settles.
+    private startCycle(): Promise<void> {
-    private startCycle(
+        const cycle = this.refreshCycle();
        isRefresh: boolean,
        work: () => Promise<void>,
    ): Promise<void> {
        const cycle = work();
        this.cycle = cycle;
        this.cycleIsRefresh = isRefresh;
        void cycle.then(
            () => {
                if (this.cycle === cycle) this.cycle = undefined;
@@ -816,9 +802,9 @@ export class Library {
            this.lastError = undefined;
            this.emit({ operation: "refresh", status: "done" });
            // Backfill ML data for the files this refresh knows about. It runs
-            // outside the refresh's success or failure, so a fetch or disk
+            // outside the refresh's success/failure so a fetch or disk problem
-            // problem there never marks the metadata refresh failed. It is not
+            // there never marks the metadata refresh failed, and it is not
-            // awaited, so it never stalls the refresh interval. Its failure is
+            // awaited so it never stalls the refresh interval. Its failure is
            // reported through `status()` and `onProgress`.
            void this.fetchMLDataNow().catch(() => {});
        } catch (err) {
@@ -831,14 +817,11 @@ export class Library {
    // Fetch every change since the stored cursor, then commit. All network
    // reads happen before any store mutation, so a fetch that throws leaves the
-    // store untouched and the previous snapshot intact.
+    // store untouched and the previous snapshot intact. A collection or file
-    //
+    // that does not decrypt is left out instead, as if deleted, with the reason
-    // From a stored cursor of 0, the server lists every live collection. The
+    // kept in the store: the cursor moves past it, so no later refresh sees it
-    // refresh then replaces all the store holds, and counts every collection
+    // again until the server's copy changes.
    // as new. Only `refreshCollection()` can have stored anything before it.
    // So the store ends as it would had `refreshCollection()` never run.
    private async refreshOnce(): Promise<void> {
        const replace = this.store.collectionsSinceTime === 0;
        const page = await this.client.collectionsSince({
            sinceTime: this.store.collectionsSinceTime,
        });
@@ -846,19 +829,16 @@ export class Library {
        // Stage per-collection file diffs. A collection's files are
        // re-enumerated only when its updationTime has advanced past the cached
        // copy; an unchanged album's file list cannot have changed. New
-        // collections enumerate from the beginning of time. When the refresh
+        // collections enumerate from the beginning of time. Each collection
        // replaces the store, every collection counts as new. Each collection
        // whose files are fetched is reported, with how many there are to
        // fetch.
        const storedCopy = (id: number): Collection | undefined =>
            replace ? undefined : this.store.getCollection(id);
        const changedCollections = page.collections.filter((collection) => {
-            const known = storedCopy(collection.id);
+            const known = this.store.getCollection(collection.id);
            return !known || collection.updationTime > known.updationTime;
        });
        const filePages: { collectionID: number; page: FilesPage }[] = [];
        for (const collection of changedCollections) {
-            const known = storedCopy(collection.id);
+            const known = this.store.getCollection(collection.id);
            const filePage = await this.client.filesSince({
                collectionID: collection.id,
                collectionKey: collection.key,
@@ -873,56 +853,8 @@ export class Library {
            });
        }
-        await this.commit(page, filePages, replace);
+        // Network work done; commit to the store and persist only if something
-    }
+        // actually changed.
    // `refreshCollection()`'s work, run in the slot: fetch the files of one
    // collection changed since the stored copy, then commit. It resolves to
    // whether the store then holds the collection.
    private async refreshCollectionOnce(
        collection: Collection,
    ): Promise<boolean> {
        const known = this.store.getCollection(collection.id);
        // A refresh has received the account's collections, and this one is
        // not stored. It is new since then, or a refresh dropped it. Leave it
        // to the next refresh, which adds new collections after the stored
        // ones, in the server's order.
        if (!known && this.store.collectionsSinceTime > 0) return false;
        // The stored copy is as new or newer, so there is nothing to fetch.
        if (known && collection.updationTime <= known.updationTime) return true;
        const filePage = await this.client.filesSince({
            collectionID: collection.id,
            collectionKey: collection.key,
            sinceTime: known ? known.updationTime : 0,
        });
        // The stored cursor stays where it is, so the next refresh still
        // fetches the files of every other collection that changed.
        await this.commit(
            {
                collections: [collection],
                deleted: [],
                cursor: this.store.collectionsSinceTime,
            },
            [{ collectionID: collection.id, page: filePage }],
            false,
        );
        return true;
    }
    // Commit a collections page and the file pages fetched for its collections
    // to the store. With `replace`, the page lists every live collection, so
    // the commit first deletes every stored collection. A collection or file
    // that does not decrypt is left out, as if deleted. The reason is kept in
    // the store. Until the server's copy changes, only a refresh from a stored
    // cursor of 0 fetches it again. Last, save the store when it holds changes
    // not yet saved.
    private async commit(
        page: CollectionsPage,
        filePages: { collectionID: number; page: FilesPage }[],
        replace: boolean,
    ): Promise<void> {
        // The network work is done, so change the store now. `changed` says
        // whether this commit changed anything.
        let changed = false;
        if (this.store.userID !== this.userID) {
@@ -930,13 +862,6 @@ export class Library {
            changed = true;
        }
        if (replace) {
            for (const { id } of this.store.listCollections()) {
                this.store.deleteCollection(id);
                changed = true;
            }
        }
        for (const id of page.deleted) {
            if (this.store.getCollection(id)) {
                this.store.deleteCollection(id);
@@ -990,10 +915,10 @@ export class Library {
        if (changed) this.unsaved = true;
        // Reproject and notify subscribers of the delta. This tracks RAM (what
-        // reads see), so it fires whether or not the save below succeeds. A
+        // reads see), so it fires whether or not the save below succeeds; a
-        // failed save rejects the caller, and a refresh also records it in
+        // save failure surfaces separately through `status().lastError`.
-        // `status().lastError`. `lastRecords` advances on every commit that
+        // `lastRecords` advances every changed refresh so the next diff is
-        // changes something, so the next diff is against current state.
+        // against current state.
        if (changed) {
            const next = this.deriveNow();
            if (this.subscribers.size > 0) {
@@ -1004,16 +929,16 @@ export class Library {
            // Recompute the fill orders and pinned set against the new library.
            this.precache?.update(next);
        }
-        // Re-kick the fills on every commit. A finished sweep starts afresh to
+        // Re-kick the fills every cycle: a finished sweep starts afresh to pick
-        // pick up new files and retry any that failed. A running one is left
+        // up new files and retry any that failed, and a running one is left be.
        // be.
        this.precache?.start();
        // Persist whenever RAM holds changes disk has not accepted — including
        // changes an earlier cycle staged whose save failed. `unsaved` clears
-        // only once a save lands, so a later commit retries a failed save even
+        // only once a save lands, so a save failure both stays visible through
-        // when it changes nothing. A failed save rejects the caller, and a
+        // `status().lastError` (the throw below records it) and keeps being
-        // refresh also records it in `status().lastError`.
+        // retried, instead of a later empty refresh silently clearing it while
        // the on-disk cache is still behind RAM.
        if (this.unsaved) {
            await this.store.save();
            this.unsaved = false;
@@ -1029,14 +954,13 @@ export class Library {
        return this.mlFetch;
    }
-    // One ML fetch pass. It fetches, decrypts and stores the ML data of every
+    // One ML fetch pass: fetch, decrypt and store the ML data for every file
-    // file the store knows about that is not cached, or whose `updationTime`
+    // the store knows about that is not cached (or whose `updationTime` has
-    // has advanced. It fetches through the metadata pool, and updates the CLIP
+    // advanced), through the metadata pool, and update the CLIP index. For a
-    // index. For a file whose ML data does not decrypt, gunzip or parse, it
+    // file whose ML data does not decrypt, gunzip or parse, it gathers the
-    // gathers the reason instead. It puts the reasons it gathered in
+    // reason instead, and puts the reasons it gathered in `mlDataErrors` when
-    // `mlDataErrors` when it ends without failing. A failure leaves
+    // it ends without failing. A failure leaves `mlDataErrors` as it was and
-    // `mlDataErrors` as it was and is reported through `status()` and
+    // is reported through `status()` and `onProgress`, then thrown.
    // `onProgress`, then thrown.
    private async runMLFetch(): Promise<void> {
        const mldata = this.mlStore;
        // Bind so the call keeps the client as its receiver when invoked
@@ -1104,9 +1028,9 @@ export class Library {
        }));
    }
-    // The distinct files the store holds, one entry per fileID, since a file
+    // The distinct files the store holds, one entry per fileID (a file in
-    // in several collections shares its ML data. Each entry carries the key
+    // several collections shares its ML data), each carrying the key and the
-    // and the newest `updationTime` seen across the file's memberships.
+    // newest `updationTime` seen across its memberships.
    private uniqueFiles(): {
        id: number;
        key: Uint8Array;
@@ -122,7 +122,7 @@ export class Precache {
    }
    // Recompute the fill orders and the pinned set from the current projection.
-    // Called at open and after every change to the store.
+    // Called at open and after every refresh that changes the library.
    update(records: DerivedRecords): void {
        const photos = [...records.photos.values()].sort(
            (a, b) => b.takenAt - a.takenAt || b.fileID - a.fileID,
@@ -71,14 +71,13 @@ export interface LibrarySnapshot {
    takenAt: number;
 }
 // What one refresh or `refreshCollection()` changed in the records.
 export interface LibraryChange {
-    // Full records for albums/photos added or changed.
+    // Full records for albums/photos added or changed by the refresh.
    albumsChanged: AlbumRecord[];
    photosChanged: PhotoRecord[];
    fileIDsRemoved: number[];
    albumIDsRemoved: number[];
-    // Wall-clock milliseconds when the store changed.
+    // Wall-clock milliseconds of the refresh that produced this change.
    refreshedAt: number;
 }
@@ -3,7 +3,7 @@
 // The store keeps one `metadata.json` file holding the account's server
 // state: the user id, a schema version, the cursor for the incremental
 // collections listing, the decrypted collection and file records, and the
-// collections and files that did not decrypt. The whole file is read
+// collections and files the refresh could not decrypt. The whole file is read
 // into RAM on load and rewritten as a whole on save; there is no partial
 // update and no lock file. A separate refresh unit populates the store from
 // the server — this module only stores what it is given.
@@ -34,11 +34,9 @@ const FILE_MODE = 0o600;
 type StoredCollection = Omit<Collection, "key"> & { key: string };
 type StoredFile = Omit<EnteFile, "key"> & { key: string };
-// A collection, or with `fileID` a file in it, that did not decrypt or parse,
+// A collection, or with `fileID` a file in it, that the last refresh to fetch
-// and why. A refresh or `refreshCollection()` records it on fetching such a
+// it could not decrypt or parse, and why. It is kept until a later refresh
-// copy. A later fetch drops it on getting a copy that decrypts, or on learning
+// fetches it again, because a refresh fetches only what changed.
 // that the server deleted it. Each fetch asks only for what changed, so the
 // store keeps the record between fetches.
 export interface Undecryptable {
    collectionID: number;
    fileID?: number;
@@ -72,6 +70,12 @@ export class MetadataStore {
    userID = 0;
    collectionsSinceTime: Microseconds = 0;
    // True when `load` populated this store from a valid existing file; false
    // on a first run or a missing/corrupt/wrong-version file that loaded empty.
    // `Library.open` reads it to decide whether the first refresh may run in
    // the background (an existing copy already serves reads) or must be awaited.
    loadedFromDisk = false;
    private readonly collections = new Map<number, Collection>();
    private readonly files = new Map<string, EnteFile>();
    private undecryptable: Undecryptable[] = [];
@@ -98,6 +102,7 @@ export class MetadataStore {
            if (parsed.schemaVersion !== METADATA_SCHEMA_VERSION) {
                return store;
            }
            store.loadedFromDisk = true;
            store.userID = parsed.userID ?? 0;
            store.collectionsSinceTime = parsed.collectionsSinceTime ?? 0;
            for (const stored of parsed.collections ?? []) {
@@ -224,14 +229,8 @@ export class MetadataStore {
        this.files.delete(fileKey(collectionID, fileID));
    }
    // Sorted by collection ID, then file ID, so the order does not depend on
    // when each record was fetched.
    listUndecryptable(): Undecryptable[] {
-        return [...this.undecryptable].sort(
+        return [...this.undecryptable];
            (a, b) =>
                a.collectionID - b.collectionID ||
                (a.fileID ?? 0) - (b.fileID ?? 0),
        );
    }
    // Replaces any earlier record of the same collection or file.
@@ -5,7 +5,7 @@ import type { Client } from "./client.js";
 import type { Library } from "./library/index.js";
 import { ApiError } from "./api/client.js";
 import { encryptBlob, toBase64 } from "./crypto/index.js";
-import type { EnteFile } from "./model/types.js";
+import type { Collection, EnteFile } from "./model/types.js";
 // The server refuses a thumbnail larger than the one it already records for the
 // file (`thumbnail.size`, the encrypted size), so these encodings are tried
@@ -226,16 +226,18 @@ const encryptThumbnailWithin = (
    return undefined;
 };
-// Regenerate and upload a thumbnail for each requested file. Originals are read
+// Regenerate and upload a thumbnail for each requested file. `found` holds the
-// through the library's content cache (`photo.original()`); the generated
+// record of each requested file that a collection holds, and the collection it
-// thumbnail is JPEG-encoded, encrypted under the file's own key, and registered
+// was found in. Each original is read through the library's content cache, by
-// with the server — the encrypt-and-upload path is unchanged. Each file is
+// `lib.originalOf(file)`. The new thumbnail is a JPEG, encrypted under the
 // file's own key. It is uploaded, then registered with the server. Each file is
 // resolved to one outcome (fixed / skipped / failed) and a failure on one file
 // never stops the others.
 export const fixMissingThumbnails = async (
    lib: Library,
    client: Client,
    fileIDs: number[],
    found: Map<number, { file: EnteFile; collection: Collection }>,
    onProgress?: ProgressCallback,
 ): Promise<ThumbnailFixResult[]> => {
    const log = onProgress ?? (() => {});
@@ -243,31 +245,8 @@ export const fixMissingThumbnails = async (
    const api = client.getApiClient();
    const { userID } = client.whoami();
    // Resolve each requested fileID to its file record and owning album by
    // enumerating the library, each file taken from the first album that holds
    // it. The raw `EnteFile` carries the per-file key the thumbnail is
    // encrypted under, which the projected records deliberately do not.
    const wanted = new Set(fileIDs);
    const fileMap = new Map<
        number,
        { file: EnteFile; collectionName: string }
    >();
    for (const album of lib.albums.list()) {
        for (const photo of album.photos.list()) {
            if (!wanted.has(photo.fileID) || fileMap.has(photo.fileID))
                continue;
            const file = lib.getFile(album.collectionID, photo.fileID);
            if (file) {
                fileMap.set(photo.fileID, {
                    file,
                    collectionName: album.name,
                });
            }
        }
    }
    for (const fileID of fileIDs) {
-        const entry = fileMap.get(fileID);
+        const entry = found.get(fileID);
        if (!entry) {
            results.push({
                fileID,
@@ -279,7 +258,8 @@ export const fixMissingThumbnails = async (
            continue;
        }
-        const { file, collectionName } = entry;
+        const { file } = entry;
        const collectionName = entry.collection.name;
        const title = file.metadata.title;
        const skipReason = reasonToSkip(file, userID);
@@ -297,15 +277,10 @@ export const fixMissingThumbnails = async (
        const maxSize = file.thumbnail.size!;
        try {
            const photo = lib.photos.byID({ fileID });
            if (!photo) {
                throw new Error("file not present in the library cache");
            }
            log(
                `[${collectionName}] Downloading ${title} for thumbnail generation...`,
            );
-            const { path } = await photo.original();
+            const { path } = await lib.originalOf(file);
            const fileBytes = new Uint8Array(readFileSync(path));
            if (!isJpeg(fileBytes)) {
@@ -418,7 +418,7 @@ describe("the first backup of the account", () => {
        expect(downloads.sort()).toEqual([100, 200, 300]);
    });
-    // The tree "Backup layout" in the README describes. Each original is at
+    // The tree under "The backup directory" in the README. Each original is at
    // its save path, `YYYY/YYYY-MM/YYYY-MM-DD/YYYY-MM-DD.<fileID>.<ext>`, with
    // the extension of its title; the live photo is its image and its video,
    // each with the extension it had inside the ZIP, and a `.livephoto.json`
@@ -7,6 +7,11 @@
 * Each test runs `bin/quak.ts`, as the smoke test does, with its session loader
 * replaced by one that records the options it is given and reports no session,
 * so the command stops before it makes any request.
 *
 * The first load of the sources `bin/quak.ts` imports compiles them, and the
 * first `init()` starts libsodium. On a loaded host that takes longer than a
 * test's timeout, so both happen here, before the tests run. Each test's
 * `vi.resetModules()` then only runs the compiled sources again.
 */
 import { mkdtempSync, rmSync } from "node:fs";
@@ -14,8 +19,13 @@ import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { afterAll, afterEach, describe, expect, it, vi } from "vitest";
 import type { ApiClientOptions } from "../../src/api/client.js";
 import "../../src/cli-commands.js";
 import { init } from "../../src/crypto/index.js";
 import "../../src/index.js";
 import { UNATTENDED_RETRY_OPTIONS } from "../../src/retry.js";
 await init();
 const loaded = vi.hoisted(() => [] as (ApiClientOptions | undefined)[]);
 vi.mock("../../src/cli-session.js", () => ({
@@ -124,35 +124,20 @@ const FILES: Record<number, EnteFile[]> = {
 // thumbnail as empty. `withNewFile` adds new.jpg (102) to Vacation, advancing
 // the collection's updationTime as the server does. `beachInWork` adds
 // beach.jpg (100) to Work as well, so that one file is in both albums.
-// `newAlbums` adds the albums A (3) and B (4), in that order, which both hold
+// `refreshError` makes listing collections fail with that message.
 // shared.jpg (300). `refreshError` makes listing collections fail with that
 // message.
 const fakeClient = (
    opts: {
        failID?: number;
        emptyThumbID?: number;
        withNewFile?: boolean;
        beachInWork?: boolean;
        newAlbums?: boolean;
        refreshError?: string;
    } = {},
 ) => {
-    let collections = opts.withNewFile
+    const collections = opts.withNewFile
        ? [{ ...COLLECTIONS[0], updationTime: 2 }, COLLECTIONS[1]]
        : COLLECTIONS;
    let files = FILES;
    if (opts.newAlbums) {
        collections = [
            ...collections,
            { ...collection(3, "A"), updationTime: 2 },
            { ...collection(4, "B"), updationTime: 2 },
        ];
        files = {
            ...files,
            3: [file(300, 3, "shared.jpg")],
            4: [file(300, 4, "shared.jpg")],
        };
    }
    if (opts.withNewFile) {
        files = {
            ...files,
@@ -209,9 +194,6 @@ const FETCHED_BOTH_ALBUMS =
    "Fetched the files of 1 of 2 collections\n" +
    "Fetched the files of 2 of 2 collections\n";
 // The same for an account with one album.
 const FETCHED_ONE_ALBUM = "Fetched the files of 1 of 1 collections\n";
 // Collects everything written to it.
 class Output {
    text = "";
@@ -584,57 +566,6 @@ describe("files", () => {
        ]);
        expect(stderr.text).toBe(FETCHED_BOTH_ALBUMS);
    });
    // `files 2` on an empty cache stores Work alone. The refresh that `files`
    // then waits for must still store Vacation first, as the server lists it.
    it("without a collection ID lists in the server's order after files 2 on an empty cache", async () => {
        const ctx = context(fakeClient({ beachInWork: true }));
        expect(await filesCommand(ctx, "2", {})).toBe(0);
        stdout.text = "";
        stderr.text = "";
        expect(await filesCommand(ctx, undefined, { json: true })).toBe(0);
        expect(
            JSON.parse(stdout.text).map(
                (row: { id: number; collectionID: number }) => [
                    row.id,
                    row.collectionID,
                ],
            ),
        ).toEqual([
            [100, 1],
            [101, 1],
            [200, 2],
        ]);
        expect(stderr.text).toBe(FETCHED_BOTH_ALBUMS);
    });
    // After a refresh, the server adds A and then B. `files 4` must not store B
    // ahead of A, so it waits for a refresh, which stores both in that order.
    it("without a collection ID lists new albums in the server's order after files with the second one's ID", async () => {
        expect(await filesCommand(context(), undefined, {})).toBe(0);
        const ctx = context(fakeClient({ newAlbums: true }));
        stdout.text = "";
        expect(await filesCommand(ctx, "4", {})).toBe(0);
        expect(stdout.text).toBe("300\timage\tshared.jpg\n");
        stdout.text = "";
        expect(await filesCommand(ctx, undefined, { json: true })).toBe(0);
        expect(
            JSON.parse(stdout.text).map(
                (row: { id: number; collectionID: number }) => [
                    row.id,
                    row.collectionID,
                ],
            ),
        ).toEqual([
            [100, 1],
            [101, 1],
            [200, 2],
            [300, 3],
        ]);
    });
 });
 describe("get and get-thumb", () => {
@@ -642,27 +573,27 @@ describe("get and get-thumb", () => {
        const out = join(root, "diagram.png");
        expect(await getCommand(context(), "200", { out })).toBe(0);
        expect(readFileSync(out)).toEqual(Buffer.alloc(7, 200));
-        expect(stderr.text).toBe(FETCHED_BOTH_ALBUMS + `7 bytes -> ${out}\n`);
+        expect(stderr.text).toBe(`7 bytes -> ${out}\n`);
    });
    it("get-thumb finds a file in any album without --collection", async () => {
        const out = join(root, "thumb.jpg");
        expect(await getThumbCommand(context(), "200", { out })).toBe(0);
        expect(readFileSync(out)).toEqual(Buffer.alloc(3, 200));
-        expect(stderr.text).toBe(FETCHED_BOTH_ALBUMS + `3 bytes -> ${out}\n`);
+        expect(stderr.text).toBe(`3 bytes -> ${out}\n`);
    });
    it("get exits 1 when no album has the file", async () => {
        const out = join(root, "x");
        expect(await getCommand(context(), "999", { out })).toBe(1);
-        expect(stderr.text).toBe(FETCHED_BOTH_ALBUMS + "File 999 not found\n");
+        expect(stderr.text).toBe("File 999 not found\n");
        expect(existsSync(out)).toBe(false);
    });
    it("get-thumb exits 1 when no album has the file", async () => {
        const out = join(root, "x");
        expect(await getThumbCommand(context(), "999", { out })).toBe(1);
-        expect(stderr.text).toBe(FETCHED_BOTH_ALBUMS + "File 999 not found\n");
+        expect(stderr.text).toBe("File 999 not found\n");
        expect(existsSync(out)).toBe(false);
    });
 });
@@ -710,7 +641,7 @@ describe("names from an album name or a title over 255 bytes", () => {
        expect(Buffer.byteLength(name)).toBe(255);
        expect(code).toBe(0);
        expect(readdirSync(dir)).toEqual([name]);
-        expect(stderr.text).toBe(FETCHED_ONE_ALBUM + `7 bytes -> ${name}\n`);
+        expect(stderr.text).toBe(`7 bytes -> ${name}\n`);
    });
    it("get-thumb cuts the title short so that thumb_ and it fit in 255 bytes, and exits 0", async () => {
@@ -722,7 +653,7 @@ describe("names from an album name or a title over 255 bytes", () => {
        expect(Buffer.byteLength(name)).toBe(255);
        expect(code).toBe(0);
        expect(readdirSync(dir)).toEqual([name]);
-        expect(stderr.text).toBe(FETCHED_ONE_ALBUM + `3 bytes -> ${name}\n`);
+        expect(stderr.text).toBe(`3 bytes -> ${name}\n`);
    });
    it("backup-metadata cuts the album name short so that its folder's name fits in 255 bytes, and exits 0", async () => {
@@ -811,7 +742,6 @@ describe("a live photo", () => {
            Buffer.from(VIDEO),
        );
        expect(stderr.text).toBe(
            FETCHED_ONE_ALBUM +
            `${IMAGE.length} bytes -> IMG_0300.heic\n` +
                `${VIDEO.length} bytes -> IMG_0300.mov\n`,
        );
@@ -866,7 +796,6 @@ describe("a live photo", () => {
        expect(readFileSync(out)).toEqual(Buffer.from(IMAGE));
        expect(readFileSync(video)).toEqual(Buffer.from(VIDEO));
        expect(stderr.text).toBe(
            FETCHED_ONE_ALBUM +
            `${IMAGE.length} bytes -> ${out}\n${VIDEO.length} bytes -> ${video}\n`,
        );
    });
@@ -881,7 +810,6 @@ describe("a live photo", () => {
        expect(existsSync(out)).toBe(false);
        expect(existsSync(join(root, "photo.mov"))).toBe(false);
        expect(stderr.text).toBe(
            FETCHED_ONE_ALBUM +
            `File 300 is a live photo, and its video would also be written to ${out}\n`,
        );
    });
@@ -1425,6 +1353,23 @@ describe("helper fix-missing-thumbnails", () => {
        ).toBe(1);
        expect(stderr.text).toBe(last);
    });
    // beach.jpg (100) is in Vacation (1) and Work (2), both updated at the same
    // time. The fixer names a file after the first album holding it in the
    // order of `Library.albums.list()`. On a tie, the album with the higher ID
    // comes first, so beach.jpg is named after Work.
    it("names a photo in two albums after the same album on an empty cache as on a cache that holds the account", async () => {
        const ctx = context(fakeClient({ beachInWork: true }));
        const opts = { file: ["100"], json: true };
        const inWork = [{ fileID: 100, collection: "Work", status: "skipped" }];
        expect(await fixMissingThumbnailsCommand(ctx, opts)).toBe(0);
        expect(JSON.parse(stdout.text)).toMatchObject(inWork);
        expect(await filesCommand(ctx, undefined, {})).toBe(0);
        stdout.text = "";
        expect(await fixMissingThumbnailsCommand(ctx, opts)).toBe(0);
        expect(JSON.parse(stdout.text)).toMatchObject(inWork);
    });
 });
 describe("backup-metadata --exif", () => {
@@ -1454,8 +1399,8 @@ describe("backup-metadata --exif", () => {
 });
 // Each test first runs `files` so the cache holds the account as it was, then
-// changes the server under it. (`collections` would not do: it reads the
+// changes the server under it. (`collections` and `files` with a collection ID
-// collection list alone and stores nothing.)
+// would not do: they store nothing.)
 describe("backup-metadata and the thumbnail helpers refresh first", () => {
    beforeEach(async () => {
        expect(await filesCommand(context(), undefined, {})).toBe(0);
@@ -1641,22 +1586,83 @@ describe("an ID given on the command line", () => {
    );
 });
-// An account with many albums (issue #210). On an empty cache `collections`
+// An account with many albums (issues #210, #217 and #222). On an empty cache
-// used to wait for a refresh that fetched and decrypted the files of every
+// `collections`, `files` with a collection ID and `get` used to wait for a
-// album, one album after another. It printed nothing until then, so on such an
+// refresh that fetched and decrypted the files of every album, one album after
-// account it seemed to hang. `files` with an album's ID did the same before it
+// another. So did `helper fix-missing-thumbnails --file` (issue #223). On such
-// listed that album (issue #217). The account here has 40 albums of one photo
+// an account they seemed to hang. The account here has 40 albums of one photo
-// each, encrypted as Ente's clients encrypt them. The fake Ente server of
+// each, encrypted as Ente's clients encrypt them, on the fake Ente server of
-// `test/ente-server.ts` serves them. A wrapper around it records the path and
+// `test/ente-server.ts`. The tests record the path and query of each request
-// query of each request quak sends. The session is the one logging in to that
+// quak sends. The session is the one logging in to that server saves.
 // server saves.
 describe("an account with many albums", () => {
    const ALBUMS = 40;
    const PASSWORD = "many-albums";
-    const paths: string[] = [];
+    const requests: string[] = [];
    let server: typeof globalThis.fetch;
    let snapshot: ClientSnapshot;
    // What `files` without a collection ID prints on an empty cache: every
    // album's photo on stdout, and on stderr each album whose files its
    // refresh fetched.
    let everyPhoto = "";
    let progress = "";
    for (let n = 1; n <= ALBUMS; n++) {
        everyPhoto += `${n * 100}\timage\tphoto-${n}.jpg\n`;
        progress += `Fetched the files of ${n} of ${ALBUMS} collections\n`;
    }
    // The key of each album, by album ID.
    const albumKeys = new Map<number, Uint8Array>();
    // A photo in album `collectionID` as the server sends it, and its original
    // encrypted as the server stores it. The original's bytes are the title.
    // These tests fetch no thumbnail. The server records a thumbnail size, so
    // `helper fix-missing-thumbnails` downloads the original before it skips
    // the photo as not a JPEG.
    const photoRow = (photo: {
        id: number;
        collectionID: number;
        title: string;
        updationTime: number;
    }): { row: Record<string, unknown>; original: Uint8Array } => {
        const photoKey = sodium.crypto_secretstream_xchacha20poly1305_keygen();
        const photoKeyBox = encryptSecretbox(
            photoKey,
            albumKeys.get(photo.collectionID)!,
        );
        const metadata = encryptStreamBlob(
            new TextEncoder().encode(
                JSON.stringify({
                    title: photo.title,
                    fileType: 0,
                    creationTime: 1000,
                    modificationTime: 1000,
                }),
            ),
            photoKey,
        );
        const original = encryptStreamBlob(
            new TextEncoder().encode(photo.title),
            photoKey,
        );
        const row = {
            id: photo.id,
            collectionID: photo.collectionID,
            ownerID: USER_ID,
            encryptedKey: toBase64(photoKeyBox.ciphertext),
            keyDecryptionNonce: toBase64(photoKeyBox.nonce),
            metadata: {
                encryptedData: toBase64(metadata.ciphertext),
                decryptionHeader: toBase64(metadata.header),
            },
            file: { decryptionHeader: toBase64(original.header) },
            thumbnail: { decryptionHeader: "" },
            info: { thumbSize: 1000 },
            updationTime: photo.updationTime,
        };
        return { row, original: original.ciphertext };
    };
    // Album n is named `Album n` and holds one photo, n * 100, titled
    // `photo-n.jpg`.
    beforeAll(async () => {
@@ -1664,8 +1670,10 @@ describe("an account with many albums", () => {
        const account = await buildAccount(PASSWORD);
        const collections: Record<string, unknown>[] = [];
        const filesByCollection: Record<number, Record<string, unknown>[]> = {};
        const fileCiphertexts: Record<number, Uint8Array> = {};
        for (let id = 1; id <= ALBUMS; id++) {
            const albumKey = sodium.crypto_secretbox_keygen();
            albumKeys.set(id, albumKey);
            const albumKeyBox = encryptSecretbox(albumKey, account.masterKey);
            const name = encryptSecretbox(
                new TextEncoder().encode(`Album ${id}`),
@@ -1681,37 +1689,14 @@ describe("an account with many albums", () => {
                type: "album",
                updationTime: 1,
            });
-            const photoKey =
+            const { row, original } = photoRow({
                sodium.crypto_secretstream_xchacha20poly1305_keygen();
            const photoKeyBox = encryptSecretbox(photoKey, albumKey);
            const metadata = encryptStreamBlob(
                new TextEncoder().encode(
                    JSON.stringify({
                        title: `photo-${id}.jpg`,
                        fileType: 0,
                        creationTime: 1000,
                        modificationTime: 1000,
                    }),
                ),
                photoKey,
            );
            filesByCollection[id] = [
                {
                id: id * 100,
                collectionID: id,
-                    ownerID: USER_ID,
+                title: `photo-${id}.jpg`,
                    encryptedKey: toBase64(photoKeyBox.ciphertext),
                    keyDecryptionNonce: toBase64(photoKeyBox.nonce),
                    metadata: {
                        encryptedData: toBase64(metadata.ciphertext),
                        decryptionHeader: toBase64(metadata.header),
                    },
                    // These tests fetch no original and no thumbnail.
                    file: { decryptionHeader: "" },
                    thumbnail: { decryptionHeader: "" },
                updationTime: 1,
-                },
+            });
-            ];
+            filesByCollection[id] = [row];
            fileCiphertexts[id * 100] = original;
        }
        const ente = buildMetaFetch({
            verifier: account.verifier,
@@ -1721,7 +1706,7 @@ describe("an account with many albums", () => {
            collections,
            filesByCollection,
            encryptedMLData: {},
-            fileCiphertexts: {},
+            fileCiphertexts,
        });
        server = (async (input: RequestInfo | URL, init?: RequestInit) => {
            const url =
@@ -1731,7 +1716,7 @@ describe("an account with many albums", () => {
                      ? input.href
                      : input.url;
            const { pathname, search } = new URL(url);
-            paths.push(pathname + search);
+            requests.push(pathname + search);
            return ente(input, init);
        }) as typeof globalThis.fetch;
        const client = await Client.login({
@@ -1743,16 +1728,17 @@ describe("an account with many albums", () => {
    });
    beforeEach(() => {
-        paths.length = 0;
+        requests.length = 0;
    });
-    // A context whose saved session sends its requests to the fake server.
+    // A context whose saved session sends its requests to `fetch`, by default
-    const accountContext = (): CliContext => {
+    // the fake server.
    const accountContext = (fetch = server): CliContext => {
        const ctx = context();
        saveSession(ctx.sessionDir, snapshot);
        return {
            ...ctx,
-            loadSession: (path) => loadSession(path, { fetch: server }),
+            loadSession: (path) => loadSession(path, { fetch }),
        };
    };
@@ -1765,72 +1751,219 @@ describe("an account with many albums", () => {
            albums += `${id}\talbum\tAlbum ${id}\n`;
        expect(stdout.text).toBe(albums);
        expect(stderr.text).toBe("");
-        expect(paths).toEqual(["/collections/v2?sinceTime=0"]);
+        expect(requests).toEqual(["/collections/v2?sinceTime=0"]);
-        // It stored nothing that would make `refreshCollection()` skip an
+        // It stored nothing that would make a refresh skip an album's files:
-        // album's files: `files` after it still finds the album's photo.
+        // `files` after it still lists every album's photo.
        stdout.text = "";
-        expect(await filesCommand(ctx, "7", {})).toBe(0);
+        expect(await filesCommand(ctx, undefined, {})).toBe(0);
-        expect(stdout.text).toBe("700\timage\tphoto-7.jpg\n");
+        expect(stdout.text).toBe(everyPhoto);
    });
-    it("files fetches the files of the album it lists and of no other", async () => {
+    it("files with a collection ID asks for the album list and that album's files alone", async () => {
        expect(await filesCommand(accountContext(), "7", {})).toBe(0);
        expect(stdout.text).toBe("700\timage\tphoto-7.jpg\n");
        expect(stderr.text).toBe("");
-        expect(paths).toEqual([
+        expect(requests).toEqual([
            "/collections/v2?sinceTime=0",
            "/collections/v2/diff?collectionID=7&sinceTime=0",
        ]);
    });
-    // The first listing stored the album, so the second finds its stored copy
+    // Here the server sends album 7's files in two pages. Photo 700 changed
-    // current and asks for no album's files.
+    // between them, so both pages hold a copy of it.
-    it("files run again for the same album sends no request for its files", async () => {
+    it("files with a collection ID lists only the later copy of a photo sent in two pages", async () => {
-        const ctx = accountContext();
+        const firstPage = [
-        expect(await filesCommand(ctx, "7", {})).toBe(0);
+            photoRow({
-        stdout.text = "";
+                id: 700,
-        paths.length = 0;
+                collectionID: 7,
                title: "photo-7.jpg",
                updationTime: 1,
            }).row,
            photoRow({
                id: 701,
                collectionID: 7,
                title: "photo-701.jpg",
                updationTime: 1,
            }).row,
        ];
        const secondPage = [
            photoRow({
                id: 700,
                collectionID: 7,
                title: "photo-7-edited.jpg",
                updationTime: 2,
            }).row,
        ];
        const paged = (async (input: RequestInfo | URL, init?: RequestInit) => {
            const url = new URL(input instanceof Request ? input.url : input);
            if (
                url.pathname !== "/collections/v2/diff" ||
                url.searchParams.get("collectionID") !== "7"
            ) {
                return server(input, init);
            }
            const first = url.searchParams.get("sinceTime") === "0";
            return new Response(
                JSON.stringify({
                    diff: first ? firstPage : secondPage,
                    hasMore: first,
                }),
            );
        }) as typeof globalThis.fetch;
-        expect(await filesCommand(ctx, "7", {})).toBe(0);
+        expect(await filesCommand(accountContext(paged), "7", {})).toBe(0);
-        expect(stdout.text).toBe("700\timage\tphoto-7.jpg\n");
+
-        expect(paths).toEqual(["/collections/v2?sinceTime=0"]);
+        // Photo 700 is listed once, with the later title, before photo 701.
        expect(stdout.text).toBe(
            "700\timage\tphoto-7-edited.jpg\n701\timage\tphoto-701.jpg\n",
        );
    });
-    it("files with no album's ID counts on stderr each album whose files its refresh fetched", async () => {
+    // The cache stays empty, so a later `files` without a collection ID still
    // fetches the files of all 40 albums.
    it("files with a collection ID stores nothing in the cache", async () => {
        const ctx = accountContext();
        expect(await filesCommand(ctx, "7", {})).toBe(0);
        expect(existsSync(join(root, "cache", "metadata.json"))).toBe(false);
        stdout.text = "";
        expect(await filesCommand(ctx, undefined, {})).toBe(0);
        expect(stdout.text).toBe(everyPhoto);
        expect(stderr.text).toBe(progress);
    });
    // Photo 200 is in album 2, so `get` asks for no file of album 3 or later.
    // The last request downloads the photo's original.
    it("get on an empty cache asks for the albums' files only until one holds the photo", async () => {
        const out = join(root, "photo.jpg");
        expect(await getCommand(accountContext(), "200", { out })).toBe(0);
        expect(readFileSync(out, "utf-8")).toBe("photo-2.jpg");
        expect(stderr.text).toBe(`11 bytes -> ${out}\n`);
        expect(requests).toEqual([
            "/collections/v2?sinceTime=0",
            "/collections/v2/diff?collectionID=1&sinceTime=0",
            "/collections/v2/diff?collectionID=2&sinceTime=0",
            "/?fileID=200",
        ]);
        expect(existsSync(join(root, "cache", "metadata.json"))).toBe(false);
    });
    // `files` first fills the cache, so `get` waits for a refresh. No album has
    // changed since, so the refresh asks for no album's files.
    it("get on a cache that holds the account asks for no unchanged album's files, also for a photo in no album", async () => {
        const ctx = accountContext();
        expect(await filesCommand(ctx, undefined, {})).toBe(0);
        requests.length = 0;
        stderr.text = "";
        const out = join(root, "photo.jpg");
        expect(await getCommand(ctx, "4000", { out })).toBe(0);
        expect(readFileSync(out, "utf-8")).toBe("photo-40.jpg");
        expect(stderr.text).toBe(`12 bytes -> ${out}\n`);
        expect(requests).toEqual([
            "/collections/v2?sinceTime=1",
            "/?fileID=4000",
        ]);
        requests.length = 0;
        stderr.text = "";
        expect(await getCommand(ctx, "999", { out })).toBe(1);
        expect(stderr.text).toBe("File 999 not found\n");
        expect(requests).toEqual(["/collections/v2?sinceTime=1"]);
    });
    // The helper searches the most recently updated album first. All 40 were
    // updated at the same time, and on a tie the higher ID comes first. Photo
    // 3900 is in album 39, so the helper asks for no file of album 38 or
    // earlier. The last request downloads the photo's original.
    it("fix-missing-thumbnails --file on an empty cache asks for the albums' files only until one holds the photo", async () => {
        const opts = { file: ["3900"], json: true };
        expect(await fixMissingThumbnailsCommand(accountContext(), opts)).toBe(
            0,
        );
        const reason =
            "unsupported image format (only baseline JPEG can be regenerated)";
        expect(JSON.parse(stdout.text)).toEqual([
            {
                fileID: 3900,
                title: "photo-39.jpg",
                collection: "Album 39",
                status: "skipped",
                reason,
            },
        ]);
        expect(stderr.text).toBe(
            "[Album 39] Downloading photo-39.jpg for thumbnail generation...\n" +
                `[Album 39] Skipping photo-39.jpg: ${reason}\n`,
        );
        expect(requests).toEqual([
            "/collections/v2?sinceTime=0",
            "/collections/v2/diff?collectionID=40&sinceTime=0",
            "/collections/v2/diff?collectionID=39&sinceTime=0",
            "/?fileID=3900",
        ]);
        expect(existsSync(join(root, "cache", "metadata.json"))).toBe(false);
    });
    // `files` first fills the cache, so the helper waits for a refresh. No
    // album has changed since, so the refresh asks for no album's files.
    it("fix-missing-thumbnails --file on a cache that holds the account asks for no unchanged album's files, also for a photo in no album", async () => {
        const ctx = accountContext();
        expect(await filesCommand(ctx, undefined, {})).toBe(0);
        requests.length = 0;
        stdout.text = "";
        stderr.text = "";
        const opts = { file: ["3900"], json: true };
        expect(await fixMissingThumbnailsCommand(ctx, opts)).toBe(0);
        const reason =
            "unsupported image format (only baseline JPEG can be regenerated)";
        expect(JSON.parse(stdout.text)).toEqual([
            {
                fileID: 3900,
                title: "photo-39.jpg",
                collection: "Album 39",
                status: "skipped",
                reason,
            },
        ]);
        expect(stderr.text).toBe(
            "[Album 39] Downloading photo-39.jpg for thumbnail generation...\n" +
                `[Album 39] Skipping photo-39.jpg: ${reason}\n`,
        );
        expect(requests).toEqual([
            "/collections/v2?sinceTime=1",
            "/?fileID=3900",
        ]);
        requests.length = 0;
        stdout.text = "";
        const notFound = { file: ["999"], json: true };
        expect(await fixMissingThumbnailsCommand(ctx, notFound)).toBe(1);
        expect(JSON.parse(stdout.text)).toMatchObject([
            { fileID: 999, reason: "file not found in any collection" },
        ]);
        expect(requests).toEqual(["/collections/v2?sinceTime=1"]);
    });
    it("files counts on stderr each album whose files its refresh fetched", async () => {
        expect(await filesCommand(accountContext(), undefined, {})).toBe(0);
-        let photos = "";
+        expect(stdout.text).toBe(everyPhoto);
        let progress = "";
        for (let n = 1; n <= ALBUMS; n++) {
            photos += `${n * 100}\timage\tphoto-${n}.jpg\n`;
            progress += `Fetched the files of ${n} of ${ALBUMS} collections\n`;
        }
        expect(stdout.text).toBe(photos);
        expect(stderr.text).toBe(progress);
    });
    // `--json` shapes stdout only, so the refresh's progress is still counted
    // on stderr.
-    it("files --json with no album's ID counts on stderr each album whose files its refresh fetched", async () => {
+    it("files --json counts on stderr each album whose files its refresh fetched", async () => {
-        expect(
+        const opts = { json: true };
-            await filesCommand(accountContext(), undefined, { json: true }),
+        expect(await filesCommand(accountContext(), undefined, opts)).toBe(0);
        ).toBe(0);
-        const rows = JSON.parse(stdout.text);
+        expect(JSON.parse(stdout.text)).toHaveLength(ALBUMS);
        expect(rows).toHaveLength(ALBUMS);
        expect(rows[6]).toEqual({
            id: 700,
            title: "photo-7.jpg",
            fileType: "image",
            creationTime: 1000,
            collectionID: 7,
        });
        let progress = "";
        for (let n = 1; n <= ALBUMS; n++) {
            progress += `Fetched the files of ${n} of ${ALBUMS} collections\n`;
        }
        expect(stderr.text).toBe(progress);
    });
 });
@@ -234,13 +234,15 @@ describe("-q", () => {
        });
    });
-    // The line saying why the command failed is the fatal one, and it is
+    // No album holds file 999, so fixing it fails. The summary from
-    // printed.
+    // `--- Done ---` to the end of the `Failed files:` list is left out. The
    // line saying why the command failed is the fatal one, and it is printed.
    it("prints only the line a failing command exits with", async () => {
-        expect(await quak("-q", "files", "9")).toEqual({
+        const fix = ["helper", "fix-missing-thumbnails", "--file", "999"];
        expect(await quak("-q", ...fix)).toEqual({
            code: 1,
            stdout: "",
-            stderr: "Collection 9 not found\n",
+            stderr: `quak: 1 file(s) failed; see the "Failed files:" list, or the JSON with --json\n`,
        });
    });
@@ -326,7 +328,7 @@ describe("what the library reports", () => {
        ]);
    });
-    // Each operation is named in plain words, as the README names it.
+    // Each operation is named in plain words.
    it("logs a refresh's progress at info, and its start and end at debug", () => {
        const { log, lines } = collect();
        const onProgress = logRefresh(log);
@@ -3,25 +3,25 @@
 * issue #36, issue #52).
 *
 * The `collections`, `files`, `get`, and `get-thumb` commands must answer for
- * current server state, not the local cache. `files` without a collection ID,
+ * current server state, not the local cache. `get`, `get-thumb` and `files`
- * `get` and `get-thumb` force a `Library.fresh()` round-trip before they read.
+ * without a collection ID force a `Library.fresh()` round-trip before they
- * The stand-in library below serves nothing until `fresh()` has been awaited.
+ * read. The stand-in library below serves no cached record until `fresh()` has
- * A helper that read without refreshing would come back empty and fail here.
+ * been awaited, so a helper that read without refreshing would come back empty
- * `collections` asks the library for the collection list alone
+ * and fail here. `collections` asks the library for the collection list alone
- * (`freshCollections()`, issue #210). It must not wait for a refresh, which
+ * (`freshCollections()`, issue #210). `files` with a collection ID asks for
- * would fetch the files of every collection. `files COLLECTION` reads that list
+ * that list, then for that one collection's files (`freshFiles()`, issue
- * too, then brings that one collection up to date (`refreshCollection()`,
+ * #217). Neither may wait for a refresh, which would fetch the files of every
- * issue #217). The stand-in serves a collection's files once `fresh()` has run,
+ * collection. On an empty cache, `get` and `get-thumb` ask for that list, then
- * or once `refreshCollection()` has resolved to `true` for that collection.
+ * for one collection's files at a time, until they find the file (issue #222).
- * When `refreshCollection()` resolves to `false`, `files COLLECTION` forces a
+ * `helper fix-missing-thumbnails --file` does the same until it finds every
- * refresh instead.
+ * file it names, reading the most recently updated collection first (issue
 * #223).
 *
- * `collections` and `files` also list in the library's enumeration order
+ * `collections` and `files` also list in the order the library gives them, not
 * (`listCollections`/`listFiles`) — the order the pre-library CLI printed — not
 * the albums/photos projection's newest-first order. The fixtures are seeded in
- * an enumeration order that a newest-first sort would rearrange, so a
+ * an order that a newest-first sort would rearrange, so a regression to the
- * regression to the projection order would fail here too. Field values still
+ * projection order would fail here too. Field values still come from the raw
- * come from the raw metadata via `cli-output.ts`.
+ * metadata via `cli-output.ts`.
 */
 import { describe, it, expect } from "vitest";
@@ -30,10 +30,10 @@ import {
    freshCollections,
    freshFiles,
    freshFile,
    freshFilesByID,
    type FreshReadLibrary,
 } from "../../src/cli-read.js";
 import { fileListRow } from "../../src/cli-output.js";
 import type { Photo } from "../../src/library/index.js";
 import type { Collection, EnteFile } from "../../src/model/types.js";
 const collection = (id: number, updationTime: number): Collection => ({
@@ -67,20 +67,15 @@ const file = (
    updationTime: creationTime,
 });
-// A library that reveals its records only after `fresh()` has been awaited, and
+// A library that reveals its cached records only after `fresh()` has been
-// serves them in the enumeration order it was given. `freshCollections()`
+// awaited, and serves them in the enumeration order it was given.
-// answers the collection list in that order without a refresh. When
+// `freshCollections()` and `freshFiles()` answer in that order without a
-// `refreshCollection()` resolves to true, it reveals the files of that one
+// refresh.
 // collection.
 // `photos.byID` returns a stand-in `Photo` carrying just the fileID the helper
 // passes through.
 class FakeLibrary implements FreshReadLibrary {
    freshCalls = 0;
    freshCollectionsCalls = 0;
-    refreshCollectionIDs: number[] = [];
+    // The ID of each collection `freshFiles()` was asked for.
-    // What `refreshCollection()` resolves to. With false it reveals nothing,
+    freshFilesCalls: number[] = [];
    // as a library that has had a refresh does for a collection it lacks.
    refreshCollectionHolds = true;
    private refreshed = false;
    constructor(
@@ -99,14 +94,9 @@ class FakeLibrary implements FreshReadLibrary {
        return this.collections;
    }
-    async refreshCollection(collection: Collection): Promise<boolean> {
+    async freshFiles(collection: Collection): Promise<EnteFile[]> {
-        this.refreshCollectionIDs.push(collection.id);
+        this.freshFilesCalls.push(collection.id);
-        return this.refreshCollectionHolds;
+        return this.files.filter((f) => f.collectionID === collection.id);
    }
    getCollection(id: number): Collection | undefined {
        if (!this.refreshed) return undefined;
        return this.collections.find((c) => c.id === id);
    }
    listCollections(): Collection[] {
@@ -114,11 +104,7 @@ class FakeLibrary implements FreshReadLibrary {
    }
    listFiles(collectionID: number): EnteFile[] {
-        const current =
+        return this.refreshed
            this.refreshed ||
            (this.refreshCollectionHolds &&
                this.refreshCollectionIDs.includes(collectionID));
        return current
            ? this.files.filter((f) => f.collectionID === collectionID)
            : [];
    }
@@ -127,14 +113,6 @@ class FakeLibrary implements FreshReadLibrary {
        if (!this.refreshed) return undefined;
        return this.files.find((f) => f.id === fileID);
    }
    photos = {
        byID: ({ fileID }: { fileID: number }): Photo | undefined => {
            if (!this.refreshed) return undefined;
            if (!this.files.some((f) => f.id === fileID)) return undefined;
            return { fileID } as unknown as Photo;
        },
    };
 }
 describe("CLI read helpers (issue #36 amendment, issue #52)", () => {
@@ -158,10 +136,9 @@ describe("CLI read helpers (issue #36 amendment, issue #52)", () => {
        expect(rows.map((c) => c.id)).not.toEqual(newestFirst);
    });
-    it("freshFiles brings the collection alone up to date, lists in enumeration order, keeps raw fields", async () => {
+    it("freshFiles with a collection ID reads that collection's files alone and keeps their order and raw fields", async () => {
-        // Enumeration order by id 10, 11, 12; creationTimes ascending, so a
+        // Given in the order 10, 11, 12; creationTimes ascending, so a
-        // newest-first sort would reverse them. Collection 2's file is not
+        // newest-first sort would reverse them.
        // listed.
        const files = [
            file(10, 1, 1_700_000_000_000_000),
            file(11, 1, 1_700_000_000_000_001),
@@ -169,14 +146,14 @@ describe("CLI read helpers (issue #36 amendment, issue #52)", () => {
            file(20, 2, 1_700_000_000_000_003),
        ];
        const lib = new FakeLibrary(
-            [collection(1, 100), collection(2, 100)],
+            [collection(1, 100), collection(2, 200)],
            files,
        );
        const rows = await freshFiles(lib, 1);
        expect(lib.freshCollectionsCalls).toBe(1);
        expect(lib.refreshCollectionIDs).toEqual([1]);
        expect(lib.freshCalls).toBe(0);
        expect(lib.freshCollectionsCalls).toBe(1);
        expect(lib.freshFilesCalls).toEqual([1]);
        expect(rows?.map((f) => f.id)).toEqual([10, 11, 12]);
        // Field values come from raw metadata: microsecond creationTime and the
@@ -230,45 +207,120 @@ describe("CLI read helpers (issue #36 amendment, issue #52)", () => {
        ]);
    });
    it("freshFiles forces a refresh when refreshCollection resolves to false", async () => {
        const lib = new FakeLibrary(
            [collection(1, 100)],
            [file(10, 1, 1_700_000_000_000_000)],
        );
        lib.refreshCollectionHolds = false;
        const rows = await freshFiles(lib, 1);
        expect(lib.refreshCollectionIDs).toEqual([1]);
        expect(lib.freshCalls).toBe(1);
        expect(rows?.map((f) => f.id)).toEqual([10]);
    });
    it("freshFiles returns undefined for an unknown collection", async () => {
        const lib = new FakeLibrary([collection(1, 100)], []);
        const rows = await freshFiles(lib, 999);
        expect(lib.freshCollectionsCalls).toBe(1);
        expect(lib.refreshCollectionIDs).toEqual([]);
        expect(lib.freshCalls).toBe(0);
        expect(lib.freshFilesCalls).toEqual([]);
        expect(rows).toBeUndefined();
    });
-    it("freshFile refreshes first, then resolves the photo and its raw record", async () => {
+    // Three collections, each holding one file.
-        const f = file(10, 1, 1_700_000_000_000_000);
+    const threeCollections = (): FakeLibrary =>
-        const lib = new FakeLibrary([collection(1, 100)], [f]);
+        new FakeLibrary(
-
+            [collection(1, 100), collection(2, 200), collection(3, 300)],
-        const resolved = await freshFile(lib, 10);
+            [
-        expect(lib.freshCalls).toBe(1);
+                file(10, 1, 1_700_000_000_000_000),
-        expect(resolved?.photo.fileID).toBe(10);
+                file(20, 2, 1_700_000_000_000_001),
-        expect(resolved?.file.metadata.title).toBe("file-10.jpg");
+                file(30, 3, 1_700_000_000_000_002),
-        expect(resolved?.file.metadata.creationTime).toBe(
+            ],
            1_700_000_000_000_000,
        );
    it("freshFile on an empty cache reads each collection's files in the server's order until one holds the file", async () => {
        const lib = threeCollections();
        const found = await freshFile(lib, 20);
        expect(lib.freshCalls).toBe(0);
        expect(lib.freshCollectionsCalls).toBe(1);
        expect(lib.freshFilesCalls).toEqual([1, 2]);
        expect(found?.metadata.title).toBe("file-20.jpg");
        expect(found?.metadata.creationTime).toBe(1_700_000_000_000_001);
    });
-    it("freshFile returns undefined for an unknown file", async () => {
+    // The stand-in's cache holds what the server holds once `fresh()` has run.
-        const lib = new FakeLibrary([collection(1, 100)], []);
+    it("freshFile on a cache that holds the collections refreshes, then looks the file up in the cache", async () => {
-        const resolved = await freshFile(lib, 404);
+        const lib = threeCollections();
-        expect(lib.freshCalls).toBe(1);
+        await lib.fresh();
-        expect(resolved).toBeUndefined();
+
        const found = await freshFile(lib, 30);
        expect(lib.freshCalls).toBe(2);
        expect(lib.freshCollectionsCalls).toBe(0);
        expect(lib.freshFilesCalls).toEqual([]);
        expect(found?.collectionID).toBe(3);
    });
    it("freshFile on an empty cache returns undefined for an unknown file, after reading every collection's files", async () => {
        const lib = threeCollections();
        const found = await freshFile(lib, 404);
        expect(lib.freshCalls).toBe(0);
        expect(lib.freshFilesCalls).toEqual([1, 2, 3]);
        expect(found).toBeUndefined();
    });
    // The server lists collections 1, 2 and 3, and collection 3 was updated
    // most recently. File 11 is in collections 1 and 2.
    const fileInTwoCollections = (): FakeLibrary =>
        new FakeLibrary(
            [collection(1, 100), collection(2, 200), collection(3, 300)],
            [
                file(10, 1, 1_700_000_000_000_000),
                file(11, 1, 1_700_000_000_000_001),
                file(11, 2, 1_700_000_000_000_001),
                file(20, 2, 1_700_000_000_000_002),
                file(30, 3, 1_700_000_000_000_003),
            ],
        );
    it("freshFilesByID on an empty cache reads the most recently updated collection's files first, until it has found every file", async () => {
        const lib = fileInTwoCollections();
        const found = await freshFilesByID(lib, [11, 20]);
        expect(lib.freshCalls).toBe(0);
        expect(lib.freshCollectionsCalls).toBe(1);
        expect(lib.freshFilesCalls).toEqual([3, 2]);
        expect(found.get(11)?.collection.id).toBe(2);
        expect(found.get(11)?.file.collectionID).toBe(2);
        expect(found.get(20)?.collection.id).toBe(2);
    });
    // Collection 1 was updated last, though collections 2 and 3 have higher
    // IDs. File 11 is in collections 1 and 2.
    it("freshFilesByID on an empty cache reads the most recently updated collection first, though its ID is the lowest", async () => {
        const lib = new FakeLibrary(
            [collection(1, 400), collection(2, 200), collection(3, 300)],
            [
                file(11, 1, 1_700_000_000_000_001),
                file(11, 2, 1_700_000_000_000_001),
            ],
        );
        const found = await freshFilesByID(lib, [11]);
        expect(lib.freshFilesCalls).toEqual([1]);
        expect(found.get(11)?.collection.id).toBe(1);
        expect(found.get(11)?.file.collectionID).toBe(1);
    });
    // The stand-in's cache holds what the server holds once `fresh()` has run.
    it("freshFilesByID on a cache that holds the collections refreshes, then finds each file in the most recently updated collection that holds it", async () => {
        const lib = fileInTwoCollections();
        await lib.fresh();
        const found = await freshFilesByID(lib, [11, 404]);
        expect(lib.freshCalls).toBe(2);
        expect(lib.freshCollectionsCalls).toBe(0);
        expect(lib.freshFilesCalls).toEqual([]);
        expect(found.get(11)?.collection.id).toBe(2);
        expect(found.get(11)?.file.collectionID).toBe(2);
        expect(found.has(404)).toBe(false);
    });
    it("freshFilesByID on an empty cache reads every collection's files when a file is in none of them", async () => {
        const lib = fileInTwoCollections();
        const found = await freshFilesByID(lib, [10, 404]);
        expect(lib.freshFilesCalls).toEqual([3, 2, 1]);
        expect(found.get(10)?.collection.id).toBe(1);
        expect(found.has(404)).toBe(false);
    });
 });
@@ -19,8 +19,11 @@ import { SRP, SrpServer } from "fast-srp-hap";
 import { toBase64, deriveKEK, deriveLoginSubkey } from "../src/crypto/index.js";
 import type { KeyAttributes } from "../src/auth/types.js";
-const TEST_OPS = 2;
+// The account's password is stretched at libsodium's lowest Argon2id cost.
-const TEST_MEM = 64 * 1024 * 1024;
+// Every login stretches it again, and at a realistic cost that takes seconds on
 // a loaded host.
 const TEST_OPS = 1;
 const TEST_MEM = 8192;
 export interface MetaMockState {
    verifier: Buffer;
@@ -253,6 +253,12 @@ describe("Library content wiring", () => {
        await expect(
            lib.thumbnails.ensure({ fileIDs: [1], priority: "visible" }),
        ).rejects.toThrow(/content cache/i);
        await expect(lib.originalOf(file(1, 1))).rejects.toThrow(
            /content cache/i,
        );
        await expect(lib.thumbnailOf(file(1, 1))).rejects.toThrow(
            /content cache/i,
        );
        await lib.close();
    });
 });
@@ -375,6 +375,25 @@ describe("ContentCache.original / thumbnail", () => {
        await cache.open();
        await expect(cache.original(999)).rejects.toThrow(/unknown file/i);
    });
    // `getFile` knows no file here, so the cache can fetch only the file it is
    // given.
    it("originalOf and thumbnailOf fetch and cache the file they are given", async () => {
        const { cache, source } = buildCache({ files: [] });
        await cache.open();
        const original = await cache.originalOf(file(5));
        const thumbnail = await cache.thumbnailOf(file(5));
        expect(source.originalCalls).toEqual([5]);
        expect(source.thumbnailCalls).toEqual([5]);
        expect(original.path).toBe(join(cacheDir, "originals", "5.jpg"));
        expect(thumbnail.path).toBe(join(cacheDir, "thumbnails", "5.jpg"));
        expect(cache.pathsFor(5)).toEqual({
            originalPath: original.path,
            thumbnailPath: thumbnail.path,
        });
    });
 });
 describe("ContentCache.ensureThumbnails", () => {
@@ -17,14 +17,6 @@
 *  4. `freshCollections()` reads the collection list alone, with one request
 *     and no collection's files, and stores nothing, so the next refresh still
 *     fetches the files of every collection (issue #210).
 *  5. `refreshCollection()` brings one collection up to date in the store
 *     (issue #217). It leaves the stored cursor where it was, so the next
 *     refresh still fetches the files of every other collection that changed.
 *     It never runs at the same time as a refresh. After a refresh, it stores
 *     no collection the store does not hold: not a new one, and not one a
 *     refresh deleted. `close()` waits for it. A library opened on a cache that
 *     only it wrote awaits its first refresh. That refresh replaces what it
 *     stored, in the server's order.
 *
 * The client is the same metadata-only mock the background-refresh tests use:
 * no crypto, no network, scripted pages, and a record of each call. A long
@@ -38,7 +30,6 @@ import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { Library } from "../../src/library/index.js";
 import { MetadataStore } from "../../src/library/store.js";
 import type { CollectionsPage, FilesPage } from "../../src/client.js";
 import type { Collection, EnteFile } from "../../src/model/types.js";
@@ -153,26 +144,6 @@ const openSeeded = async (
    return { client, lib };
 };
 // Hold the client's next files request until `release()` is called. `started`
 // resolves once that request has been sent.
 const holdNextFilesRequest = (
    client: MockClient,
 ): { started: Promise<void>; release: () => void } => {
    let release!: () => void;
    const held = new Promise<void>((r) => (release = r));
    let sent!: () => void;
    const started = new Promise<void>((r) => (sent = r));
    const realFilesSince = client.filesSince.bind(client);
    client.filesSince = async (args) => {
        client.filesSince = realFilesSince;
        const page = await realFilesSince(args);
        sent();
        await held;
        return page;
    };
    return { started, release };
 };
 describe("Library.fresh", () => {
    let dir: string;
    let cacheDirectory: string;
@@ -316,10 +287,10 @@ describe("Library.freshCollections", () => {
        rmSync(dir, { recursive: true, force: true });
    });
-    // A refresh from a stored cursor past 0 fetches a collection's files only
+    // A refresh fetches a collection's files only when the collection is new
-    // when the collection is new or its updationTime has advanced past the
+    // or its updationTime has advanced past the stored copy's. Had the
-    // stored copy's. So does `refreshCollection()`. Neither would fetch the
+    // collection list been stored, the next refresh would take every
-    // files of a collection stored here without them.
+    // collection for one it already holds the files of, and fetch none.
    it("asks for the collection list alone and stores nothing", async () => {
        const client = new MockClient();
        const page = {
@@ -369,243 +340,3 @@ describe("Library.freshCollections", () => {
        }
    });
 });
 describe("Library.refreshCollection", () => {
    let dir: string;
    let cacheDirectory: string;
    beforeEach(() => {
        dir = mkdtempSync(join(tmpdir(), "quak-refresh-collection-"));
        cacheDirectory = join(dir, "cache");
    });
    afterEach(() => {
        rmSync(dir, { recursive: true, force: true });
    });
    // Collections 1 and 2 are stored at updationTime 100, with a stored cursor
    // of 100, and then both change on the server.
    it("fetches the files of one changed collection and leaves the others to the next refresh", async () => {
        const client = new MockClient();
        client.collectionsQueue.push({
            collections: [collection(1, 100), collection(2, 100)],
            deleted: [],
            cursor: 100,
        });
        client.filesFor(1, {
            files: [file(1001, 1, 90)],
            deleted: [],
            cursor: 90,
        });
        client.filesFor(2, {
            files: [file(2001, 2, 90)],
            deleted: [],
            cursor: 90,
        });
        const lib = await Library.open({
            client,
            cacheDirectory,
            refreshIntervalSeconds: SLOW_INTERVAL,
        });
        try {
            client.filesCalls.length = 0;
            client.filesFor(1, {
                files: [file(1002, 1, 110)],
                deleted: [],
                cursor: 110,
            });
            client.filesFor(2, {
                files: [file(2002, 2, 120)],
                deleted: [],
                cursor: 120,
            });
            // Collection 1's files alone, since the stored copy.
            expect(await lib.refreshCollection(collection(1, 110))).toBe(true);
            expect(client.filesCalls).toEqual([
                { collectionID: 1, sinceTime: 100 },
            ]);
            expect(lib.listFiles(1).map((f) => f.id)).toEqual([1001, 1002]);
            expect(lib.listFiles(2).map((f) => f.id)).toEqual([2001]);
            // The stored copy is now current, so no request.
            await lib.refreshCollection(collection(1, 110));
            expect(client.filesCalls).toHaveLength(1);
            // The next refresh asks from the stored cursor, 100, so it still
            // sees collection 2 changed and fetches its files.
            client.collectionsQueue.push({
                collections: [collection(1, 110), collection(2, 120)],
                deleted: [],
                cursor: 120,
            });
            await lib.fresh();
            expect(client.collectionsSinceTimes).toEqual([0, 100]);
            expect(client.filesCalls).toEqual([
                { collectionID: 1, sinceTime: 100 },
                { collectionID: 2, sinceTime: 100 },
            ]);
            expect(lib.listFiles(2).map((f) => f.id)).toEqual([2001, 2002]);
        } finally {
            await lib.close();
        }
    });
    // Collection 1 is stored at 100. `refreshCollection()` asks for it at 110,
    // which adds file 1002. While that files request waits, a fresh read
    // starts a refresh. The server tells that refresh that collection 1 was
    // deleted at 130.
    it("holds off a refresh that starts during the files request, which then deletes the collection", async () => {
        const { client, lib } = await openSeeded(cacheDirectory);
        const files = holdNextFilesRequest(client);
        try {
            client.filesFor(1, {
                files: [file(1002, 1, 110)],
                deleted: [],
                cursor: 110,
            });
            client.collectionsQueue.push({
                collections: [],
                deleted: [1],
                cursor: 130,
            });
            const refreshing = lib.refreshCollection(collection(1, 110));
            await files.started;
            const reading = lib.fresh();
            // The refresh has not sent its collections request yet.
            await new Promise((r) => setImmediate(r));
            expect(client.collectionsSinceTimes).toEqual([0]);
            files.release();
            await refreshing;
            await reading;
            expect(client.collectionsSinceTimes).toEqual([0, 100]);
            expect(lib.getCollection(1)).toBeUndefined();
            expect(lib.listFiles(1)).toEqual([]);
        } finally {
            files.release();
            await lib.close();
        }
    });
    // `freshCollections()` lists collection 1 at 110. Before
    // `refreshCollection()` is called, a refresh learns that it was deleted at
    // 130.
    it("stores nothing for a collection that a refresh deleted before the call", async () => {
        const { client, lib } = await openSeeded(cacheDirectory);
        try {
            client.collectionsQueue.push(
                { collections: [collection(1, 110)], deleted: [], cursor: 110 },
                { collections: [], deleted: [1], cursor: 130 },
            );
            const [listed] = await lib.freshCollections();
            await lib.fresh();
            client.filesCalls.length = 0;
            expect(await lib.refreshCollection(listed)).toBe(false);
            expect(client.filesCalls).toEqual([]);
            expect(lib.getCollection(1)).toBeUndefined();
        } finally {
            await lib.close();
        }
    });
    // A refresh has stored collection 1. Collection 2 is new on the server
    // since then. Only the next refresh may add it, after collection 1.
    it("stores nothing for a collection that is new since the last refresh", async () => {
        const { client, lib } = await openSeeded(cacheDirectory);
        try {
            client.filesCalls.length = 0;
            expect(await lib.refreshCollection(collection(2, 110))).toBe(false);
            expect(client.filesCalls).toEqual([]);
            expect(lib.getCollection(2)).toBeUndefined();
        } finally {
            await lib.close();
        }
    });
    // The caller may remove the cache directory once `close()` resolves, so
    // the cache write must have landed by then.
    it("close() waits for a refreshCollection() in flight", async () => {
        const { client, lib } = await openSeeded(cacheDirectory);
        const files = holdNextFilesRequest(client);
        client.filesFor(1, {
            files: [file(1002, 1, 110)],
            deleted: [],
            cursor: 110,
        });
        const refreshing = lib.refreshCollection(collection(1, 110));
        await files.started;
        let closed = false;
        const closing = lib.close().then(() => {
            closed = true;
        });
        await new Promise((r) => setImmediate(r));
        expect(closed).toBe(false);
        files.release();
        await closing;
        const saved = await MetadataStore.load(
            join(cacheDirectory, "metadata.json"),
        );
        expect(saved.listFiles(1).map((f) => f.id)).toEqual([1001, 1002]);
        await refreshing;
    });
    // `quak files 2` on an empty cache stores collection 2 alone. A library
    // opened later on that cache must not serve it as the whole account. Its
    // first refresh replaces what the cache holds, in the server's order.
    it("open() awaits the first refresh on a cache that only refreshCollection() wrote", async () => {
        const client = new MockClient();
        client.filesFor(2, {
            files: [file(2001, 2, 90)],
            deleted: [],
            cursor: 90,
        });
        const first = await Library.open({
            client,
            cacheDirectory,
            refreshOnOpen: false,
            refreshIntervalSeconds: SLOW_INTERVAL,
        });
        expect(await first.refreshCollection(collection(2, 100))).toBe(true);
        await first.close();
        client.collectionsQueue.push({
            collections: [collection(1, 100), collection(2, 100)],
            deleted: [],
            cursor: 100,
        });
        client.filesFor(1, {
            files: [file(1001, 1, 90)],
            deleted: [],
            cursor: 90,
        });
        client.filesFor(2, {
            files: [file(2001, 2, 90)],
            deleted: [],
            cursor: 90,
        });
        client.filesCalls.length = 0;
        const lib = await Library.open({
            client,
            cacheDirectory,
            refreshIntervalSeconds: SLOW_INTERVAL,
        });
        try {
            expect(lib.status().lastRefreshAt).toBeDefined();
            expect(lib.listCollections().map((c) => c.id)).toEqual([1, 2]);
            // It fetches collection 2's files again, from the beginning.
            expect(client.filesCalls).toEqual([
                { collectionID: 1, sinceTime: 0 },
                { collectionID: 2, sinceTime: 0 },
            ]);
            expect(lib.listFiles(2).map((f) => f.id)).toEqual([2001]);
        } finally {
            await lib.close();
        }
    });
 });
@@ -20,9 +20,9 @@
 * 5. `close()` stops the timer and is idempotent, and its promise resolves
 *    only once an in-flight refresh has written the cache file.
 * 6. `cacheDirectory` defaults to the env-paths cache dir plus the user id.
- * 7. `open()` branches on the stored cursor. At 0, as on an empty cache, it
+ * 7. `open()` branches on the cache: an empty cache awaits the first refresh
- *    awaits the first refresh. Past 0 it serves the cache's copy at once and
+ *    (it has nothing to serve yet); an existing cache serves its copy at once
- *    refreshes in the background, so a slow or dead server never stalls
+ *    and refreshes in the background, so a slow or dead server never stalls
 *    opening.
 * 8. A save failure that leaves RAM ahead of disk keeps `status().lastError`
 *    set and keeps retrying the write; a later empty refresh does not clear it.
@@ -4,8 +4,7 @@
 * These are the surface the GUI consumes across Electron IPC. `snapshot()` is
 * synchronous — it reads the in-RAM store and projects it into plain records
 * (no keys) — and `subscribe({ onChange })` delivers a `LibraryChange` whenever
- * a refresh or `refreshCollection()` changes the derived records. The
+ * a background refresh actually changes the derived records. The contracts:
 * contracts:
 *
 *  1. `snapshot()` deduplicates a file across memberships into one record with
 *     every album id, orders photos newest first, and carries no key material.
@@ -172,7 +172,7 @@ describe("MetadataStore", () => {
        expect(store.listCollections()).toEqual([]);
    });
-    it("loads an empty store when the list of what did not decrypt is damaged", async () => {
+    it("loads an empty store when the list of what the refresh could not decrypt is damaged", async () => {
        // A backup reads that list on every run, so a damaged one that loaded
        // would fail every backup until the cache was deleted. A string is
        // damaged too, though JavaScript can loop over its characters.
@@ -266,23 +266,4 @@ describe("MetadataStore", () => {
        expect(store.getFile(12345, 67890)).toBeUndefined();
        expect(store.getFile(55555, 67890)?.key).toEqual(inB.key);
    });
    // A backup reports these in this order. It must not depend on whether a
    // refresh or `Library.refreshCollection()` fetched each one first.
    it("lists what did not decrypt by collection ID, then file ID", async () => {
        const store = await MetadataStore.load(path);
        store.putUndecryptable({ collectionID: 2, fileID: 7, error: "a" });
        store.putUndecryptable({ collectionID: 3, error: "b" });
        store.putUndecryptable({ collectionID: 1, fileID: 9, error: "c" });
        store.putUndecryptable({ collectionID: 2, fileID: 5, error: "d" });
        expect(
            store.listUndecryptable().map((r) => [r.collectionID, r.fileID]),
        ).toEqual([
            [1, 9],
            [2, 5],
            [2, 7],
            [3, undefined],
        ]);
    });
 });
@@ -6,10 +6,12 @@
 * working thumbnails, others return 404 or empty bodies. The tests
 * verify that the detection and repair logic handles each case correctly.
 *
- * As of issue #52 both helpers take an open `Library` for enumeration and the
+ * `listMissingThumbnails` takes an open `Library` to enumerate the files. Both
- * `Client` for the API operations that stay unchanged (the thumbnail existence
+ * helpers take the `Client` for the API operations: the thumbnail existence
- * check, and the encrypt-and-upload path). `fixMissingThumbnails` reads each
+ * check, and the encrypt-and-upload path. `fixMissingThumbnails` takes the
- * original through the library's content cache (`photo.original()`).
+ * record of each file, which these tests look up with `cachedFilesByID`. It
 * reads each original through the library's content cache, by
 * `lib.originalOf(file)`.
 *
 * `fixMissingThumbnails` is the most complex function in quak: it
 * downloads the original file, generates a JPEG thumbnail with jpeg-js,
@@ -41,6 +43,7 @@ import {
 import { SRP, SrpServer } from "fast-srp-hap";
 import { Client } from "../../src/client.js";
 import { Library } from "../../src/library/index.js";
 import { cachedFilesByID } from "../../src/cli-read.js";
 import {
    listMissingThumbnails,
    fixMissingThumbnails,
@@ -54,8 +57,11 @@ import type { RetryOptions } from "../../src/retry.js";
 const TEST_EMAIL = "thumb@example.com";
 const TEST_PASSWORD = "thumbpass";
-const TEST_OPS = 2;
+// The password is stretched at libsodium's lowest Argon2id cost. Each test
-const TEST_MEM = 64 * 1024 * 1024;
+// builds an account and logs in, and at a realistic cost that takes seconds on
 // a loaded host.
 const TEST_OPS = 1;
 const TEST_MEM = 8192;
 const TEST_TIME = 1700000000000000;
 interface ThumbMockState {
@@ -656,7 +662,12 @@ describe("fixMissingThumbnails", () => {
        const client = await login(buildThumbFetch(fixMock));
        const lib = await openLib(client);
-        const results = await fixMissingThumbnails(lib, client, [101]);
+        const results = await fixMissingThumbnails(
            lib,
            client,
            [101],
            cachedFilesByID(lib, [101]),
        );
        lib.close();
        expect(results.length).toBe(1);
@@ -693,7 +704,12 @@ describe("fixMissingThumbnails", () => {
        const client = await login(buildThumbFetch(fixMock));
        const lib = await openLib(client);
-        const results = await fixMissingThumbnails(lib, client, [999]);
+        const results = await fixMissingThumbnails(
            lib,
            client,
            [999],
            cachedFilesByID(lib, [999]),
        );
        lib.close();
        expect(results.length).toBe(1);
@@ -715,6 +731,7 @@ describe("fixMissingThumbnails", () => {
            lib,
            client,
            [101, 102],
            cachedFilesByID(lib, [101, 102]),
            (msg, level) => {
                if (level === "error") errors.push(msg);
            },
@@ -745,6 +762,7 @@ describe("fixMissingThumbnails", () => {
            lib,
            client,
            [101, 103, 104],
            cachedFilesByID(lib, [101, 103, 104]),
        );
        lib.close();
@@ -779,7 +797,12 @@ describe("fixMissingThumbnails", () => {
        const client = await login(counted.fetch);
        const lib = await openLib(client);
-        const results = await fixMissingThumbnails(lib, client, [101]);
+        const results = await fixMissingThumbnails(
            lib,
            client,
            [101],
            cachedFilesByID(lib, [101]),
        );
        lib.close();
        expect(results[0]!.status).toBe("skipped");
@@ -800,7 +823,12 @@ describe("fixMissingThumbnails", () => {
        const client = await login(counted.fetch);
        const lib = await openLib(client);
-        const results = await fixMissingThumbnails(lib, client, [101]);
+        const results = await fixMissingThumbnails(
            lib,
            client,
            [101],
            cachedFilesByID(lib, [101]),
        );
        lib.close();
        expect(results[0]!.status).toBe("skipped");
@@ -841,7 +869,12 @@ describe("fixMissingThumbnails", () => {
        const client = await login(buildThumbFetch(fixMock));
        const lib = await openLib(client);
-        const results = await fixMissingThumbnails(lib, client, [101]);
+        const results = await fixMissingThumbnails(
            lib,
            client,
            [101],
            cachedFilesByID(lib, [101]),
        );
        lib.close();
        expect(results[0]!.status).toBe("fixed");
@@ -3,8 +3,15 @@ import { configDefaults, defineConfig } from "vitest/config";
 // vitest does not read .gitignore when looking for tests. A checkout nested
 // under .claude/ has its own test/ tree, and without this exclude the suite
 // runs once per nested checkout and still reports success.
 //
 // vitest starts one worker per CPU core by default, and a shared host has
 // dozens. Four keep the suite well inside the Dockerfile's time limit. vitest
 // 2 rejects a maxWorkers below its default minWorkers, so minWorkers is set
 // too.
 export default defineConfig({
    test: {
        exclude: [...configDefaults.exclude, ".claude/**"],
        minWorkers: 1,
        maxWorkers: 4,
    },
 });
Author	SHA1	Message	Date
sneak	9c4790d969	TODO.md: open work only (closes #235 ) check / check (push) Successful in 3m25s Details Removes the Completed Steps section: dated accounts of finished work, review and merge history, and notes on past decisions. Git keeps the history. Status, Next Step and Future Steps are unchanged. The Workflow step "move Next Step to the top of Completed Steps" now reads "delete Next Step from `TODO.md`", the standard wording. The `README.md` TODO section no longer calls `TODO.md` the work log; it says the file holds the next step and the steps planned. Model: opus-5-5	2026-11-11 13:27:23 +00:00
clawbot	1f409cbbf2	Tests pass under heavy host load (closes #233 ) check / check (push) Successful in 3m21s Details The suite timed out when this host was heavily loaded. vitest now runs at most four workers instead of one per CPU core. `test/cli/bin.test.ts` loads the sources `bin/quak.ts` imports and starts libsodium once, before its tests, so no test pays for the first load. The fake accounts in `test/ente-server.ts` and `test/thumbnails/thumbnails.test.ts` stretch their passwords at libsodium's lowest Argon2id cost, since every login stretches them again. Judgement call: the login, usage, unwrap and KDF tests keep the realistic 64 MiB cost. Model: opus-5-5	2026-11-10 22:55:29 +01:00
clawbot	aeb275e137	README: the close() sentence split in two (closes #231 ) check / check (push) Canceled after 0s Details The sentence in "Opening a library" had a relative clause with its "that" left out, so "returns resolves" read as two verbs in a row. It is now two sentences; the behaviour described is unchanged and matches `close()` in `src/library/index.ts`. Model: fable-5-1 (change); opus-5-5 (landing message)	2026-10-26 19:32:03 +01:00
clawbot	67794bf5f8	README: four sentences fixed for the documents gate (closes #229 ) check / check (push) Canceled after 0s Details The documents gate on `next` failed five README sentences (#219 (comment)). Four are rewritten after a check against the code: - the keywords score sentence is split in two; - `mlData` drops the whole `clip` block, as `src/backup.ts` and `src/metadata-backup.ts` do; - a file name gets its ID past 255 bytes and a collection name past 250, and either is then cut short, as `uniqueNames` does; - `lastTriedAt` is taken once per run, after its refresh. The IDs sentence keeps `-1`: the pinned option parser passes a negative number to a command with no subcommands as an argument, so `quak get -1` reaches the ID check. Nothing else changes; `make fmt` reflowed the touched paragraphs. Model: fable-5-1 (change); opus-5-5 (landing message)	2026-10-26 18:59:28 +01:00
clawbot	b5fcbf4400	README.md rewritten sentence by sentence (closes #219 ) check / check (push) Canceled after 0s Details The old text served as the list of what to cover. The new text leads with what quak is, what it is for and how to use it. Every command, option, exit code and file layout follows in reference sections, then the library reference, then design, entrypoints and development. Every statement was checked against the code on next; the pull request lists each disagreement. Sentences stay under about 30 words, tables are lists, and no issue links or project history remain in text for users. Two code comments now name the new README sections, and the one in `src/cli-log.ts` matches "What quak prints" on stderr, stdout and exit status; a third no longer cites the README. Model: fable-5-1	2026-10-26 17:48:25 +01:00
clawbot	a1ea47f9a8	quak helper fix-missing-thumbnails --file on an empty cache stops fetching collections once it finds every file (closes #223 ) check / check (push) Canceled after 0s Details `helper fix-missing-thumbnails --file` used to wait for a refresh, which on an empty cache fetched the files of every collection. It now finds the named files through the new `freshFilesByID` in `src/cli-read.ts`, by the rule `freshFile` follows. On an empty cache it reads the collection list, then one collection's files at a time, and stores none of the collections or file records it reads. It searches the most recently updated collection first. So a file in several albums is still named after the first of them that `Library.albums.list()` lists. `fixMissingThumbnails` now takes the records the command found, and fetches each original through `lib.originalOf()`. Model: opus-5-5	2026-10-26 11:25:10 +01:00
clawbot	f65c237e2c	quak get and get-thumb on an empty cache stop fetching collections once they find the file (closes #222 ) check / check (push) Canceled after 0s Details `quak get` and `quak get-thumb` used to wait for a refresh, which on an empty cache fetched the files of every collection. Now, on an empty cache, `freshFile` reads the collection list, then one collection's files at a time, and stops at the first that holds the file. That search stores nothing. Once the cache holds the account's collections, `freshFile` refreshes as before and looks the file up in the cache. The commands fetch the content through the new `Library.originalOf()` and `Library.thumbnailOf()`, which take the file record itself, since the store may not hold it. On an empty cache they no longer print a refresh's progress lines. The `-q` test that relied on `get` refreshing now runs `helper fix-missing-thumbnails`. Model: opus-5-5	2026-10-26 10:18:28 +01:00
clawbot	af1491966c	quak files COLLECTION fetches that collection's files alone (closes #217 ) check / check (push) Canceled after 0s Details `quak files` with a collection ID used to wait for a full refresh, which on an empty cache fetched the files of every collection in the account. It now reads the collection list, then that one collection's files through the new `Library.freshFiles()`, and stores nothing. The files print in the server's order, and no refresh progress lines appear. Each file prints once, as the latest copy the server sent. `quak files` without a collection ID still waits for a refresh. Some tests ran `quak files` with a collection ID to fill the cache, to show a refresh's progress or to show what `-q` hides. They now run a command that still refreshes. Model: opus-5-5	2026-10-26 09:04:39 +01:00