file-manager/CHANGELOG.md

# Changelog

All notable changes to File Manager are documented in this file.

The format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/), and the
project uses [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

`versionCode` and `versionName` are defined in `app/build.gradle.kts`. Each Play
upload needs a **higher `versionCode`** than every previous upload.

## [Unreleased]

### Fixed

- **`.xz` extraction would have crashed on a real device.** Commons Compress declares its
  LZMA/LZMA2 support — the `.xz` compressor and the 7z format — against `org.tukaani:xz` as
  an **optional** dependency. Optional means it is not pulled in transitively, so nothing
  warned at build time, and the app went on advertising `.xz` as extractable. The first user
  to open one would have got `NoClassDefFoundError: org/tukaani/xz/FilterOptions`. The
  library is now declared, and a round-trip test covers the path that was silently missing.

- **The storage-usage screen stayed blank for ~45–60 s** on a real 55 GB volume, which
  reads as a hang even though the work was off the main thread. `UsageAnalysis` now passes
  the `FileEntry` down the recursion instead of re-`stat`ing every node — the parent's
  listing already says whether each child is a folder — so the walk costs one listing per
  directory. It also reports each child through an `onProgress` callback, and the ViewModel
  appends and re-sorts as they arrive, so the largest folders appear while the rest of the
  tree is still being measured. Found by running the app on a real phone.

- **Misleading first-run copy.** The permission prompt said "Full access was declined" on a
  device where the user had never declined anything. Reworded so it is true whether access
  was declined or simply never granted.

- **The details sheet put untranslatable English on screen.** It rendered `FileKind.name`
  directly, so "Type" read `directory`, `archive`, `apk` — enum constants rather than
  labels, and impossible to translate. Every category now has a string resource and a
  `FileKind.labelRes()` mapping alongside the existing `OperationKind.titleRes()`.

### Added

- **A trash you can actually recover from, after the fact.** The staged-delete work left a
  hole: the undo handle lived in memory, so a delete from a previous session was unreachable
  even though the files were sitting right there on the volume — and because nothing on disk
  recorded which folder an item came from, not even the *user* could put one back by hand
  with any confidence. There is now a **Trash** entry in the overflow menu that lists what is
  still there and puts a whole batch back.

  Backing it is `data/`'s first persistence: a SQLite index of staged path, original path,
  name, type, size and timestamp. Deliberately SQLite rather than Room — an annotation
  processor would be a large addition to this build for one table and three queries — and
  deliberately behind a `TrashIndex` port, so `domain/Trash` stays free of a `Context` and
  the tests drive it with a map while the real one is tested against real SQLite.

  The index is an **index, not the truth**: the staged files are the truth, and the two can
  disagree — a user can delete `.plainfiles-trash` themselves, or pull the card. So it is
  reconciled both ways. `restorableFrom` drops entries whose file has gone, `purgeExpired`
  forgets entries whose folder has gone, and a row is written *after* the move, so a crash
  between the two leaves an unindexed folder — harmless, and swept — rather than an entry
  that could never restore anything. A `TrashScreen` row is one *batch*, not one file,
  because a batch is what the user actually did and what the index records.

- **The app can receive a share, and act as a file picker.** The manifest had nothing but a
  `LAUNCHER` filter, so no other app could hand Plain Files anything at all. It now registers
  for `ACTION_SEND`/`SEND_MULTIPLE` — a bar appears over the browser, you navigate to the
  folder you want, then "Save here" — and for `ACTION_GET_CONTENT`/`OPEN_DOCUMENT`, where
  tapping a file hands it back through the existing `FileProvider`.

  Both reuse the browser rather than adding a second screen, because both are the same task
  underneath — navigate to a folder — with a different verb at the end. `data/` gains one
  port, `IncomingSource`, so a `ContentResolver` stays out of the ViewModel exactly as
  `DeleteRequestFactory` keeps one out of the delete path. A shared file is named from the
  sender's `OpenableColumns` where it offers one, goes through the same `NameAllocator` a
  paste does (so sharing the same file twice cannot overwrite the first copy), and is removed
  again if it cannot be read rather than left as a zero-byte stub. While another app is
  waiting for a file, tapping a *file* chooses it and tapping a *folder* still navigates —
  without that the user could never reach the file they were trying to choose.

  `ACTION_VIEW` is deliberately **not** registered: the app already hands files out through
  the system chooser, and registering as a viewer as well would offer Plain Files back to
  itself in that chooser. No new permissions — the merged release manifest still declares no
  `INTERNET`.

- **Recursive search.** The query box used to filter the folder you were standing in, which
  can only ever answer "is it here?" — and the usual question is "where did I put it?". It
  now walks *down* from the current folder (`domain/FileSearch`) and streams matches as they
  are found, because walking a whole volume takes tens of seconds and a blank screen for
  that long reads as a hang. Rows say where the hit was found (`Folder · Documents/2026`) and
  the app bar shows progress while the walk is still going.

  Three deliberate bounds: a matching folder is still descended into, so a folder called
  `holiday` cannot hide the matching files inside it; a hidden folder is skipped *whole*
  rather than merely filtered out, so the preference cannot be leaked around; and the walk
  stops at 200 matches, because a search returning ten thousand rows is not more useful than
  one returning two hundred. Each keystroke cancels the walk in progress instead of queueing
  behind it, and navigating away abandons the search — its results belonged to the folder
  being left.

- **Undo for delete, rename and move.** A delete is now a *move* into a hidden
  `.plainfiles-trash` folder on the same volume rather than a removal, so the snackbar can
  offer to put it back; a rename and a pasted cut record how to reverse themselves. Four
  deliberate limits, all carried in `domain/Trash`: the trash sits on the user's own volume,
  so it counts against their free space until it expires (24 hours, purged opportunistically
  so there is no startup hook to forget and no "empty trash" chore); a name taken again in
  the meantime is never overwritten, so an item returns *beside* it under a free name; a
  delete that went through Android's own dialog is not staged, because the system owns that
  one and its trash with it; and when a pasted move's landing names cannot be established
  with confidence, no undo is offered at all rather than risking putting the wrong file
  back. The undo handle is cleared the moment it is used, so a second tap cannot replay it.

- **Keep the browsed folder and view settings across process death.** `SavedStateHandle`
  carries the folder plus the sort key, direction, view mode and hidden-files setting. The
  search query, the selection and the clipboard are deliberately *not* restored — a
  restored query would hide the folder's contents on launch with no visible cause, and a
  paste that survived a reboot would be a nasty surprise.

- **7z extraction.** Commons Compress already contained a pure-Java 7z reader
  (`SevenZFile`), so this needed no new native code and no library beyond the XZ one the
  `.xz` fix above required — the docs had simply assumed the format was off-limits and said
  so in two places. The one real constraint is that 7z is the only format here that cannot
  arrive through a stream: its header sits at the end of the file, so the reader has to
  seek. That is now a capability the backend can advertise, `StorageSource.openSeekable`:
  the all-files backend answers with a real `FileChannel`, and the SAF fallback answers
  `null`, so a 7z in folder mode is refused with "needs a seekable file, which this storage
  mode cannot provide" rather than failing obscurely. Entry names go through the same
  `ArchivePath.safeRelativePath` zip-slip guard as every other format, with a test that
  plants `../evil.txt` in a real 7z and asserts it lands nowhere. 7z *creation* stays
  deferred, so ZIP is still the only writable format.

- **A two-pane layout for large screens.** A window at or above Material's "expanded"
  breakpoint — 840 dp, which a 10-inch tablet in landscape at 1280 dp clears — now splits
  into a master pane and a detail pane. Tapping a row highlights it, and the second pane
  answers "what is in there?" without a navigation step: a folder's children, or a preview
  plus the metadata for a file. Opening therefore moves to a double tap **on wide windows
  only**, because once there is somewhere to show a selection a single tap has to mean
  "show me"; phone (~411 dp) and 7-inch-portrait (~600 dp) windows keep the layout and the
  tap behaviour they already had. The root screen previews the main volume on arrival
  rather than leaving the second pane empty.

  Found while taking the tablet screenshots, where it turned out the app had **no**
  large-screen layout at all: on a 2560×1600 canvas every row was 2560 px wide with its
  content stranded in the left ~240 px.

- **M10 — store assets.** The app is named **Plain Files** (one string; the `applicationId`
  was already locked in M0). `tools/make-store-assets.sh` renders the 512×512 RGBA icon and
  the 1024×500 RGB feature graphic from the app's own icon vectors, so the store icon *is*
  the launcher icon rather than a lookalike that drifts after the next rebrand.
  `tools/make-store-screenshots.sh` normalises `adb` captures to Play's 2:1 limit per form
  factor — a phone at its native 1080×2400 is 2.22:1 and would be rejected outright.
  [docs/STORE_LISTING.md](docs/STORE_LISTING.md) has the ready-to-paste copy, length-checked
  against Play's limits, plus the permissions paragraph that the `MANAGE_EXTERNAL_STORAGE`
  declaration requires. The feature graphic's copy was verified to survive Play's
  centre-square crop by cropping the rendered PNG, not by trusting the arithmetic.

  **Screenshots:** 5 phone shots at 1080×2160, 4 on a 7-inch tablet at 1200×1920 and 4 on a
  10-inch tablet at 2560×1600 — all 24-bit RGB with no alpha, inside Play's 2:1 cap. The
  tablet sets come from AOSP AVDs, because there was no tablet hardware to hand. The
  generator now measures every capture and refuses to normalise a blank one: a headless AVD
  that has not composed the app's first frame still draws its system bars, so a
  pure-background capture is not obviously empty — and one had already been committed
  before the check existed.

- **M9 — monetisation.** Decided: a **one-time paid app at €4.49, with a 14-day launch price
  of €2.29**, both set in the Play Console. No ads, no subscription and no in-app purchases —
  which means no Billing client, no `com.android.vending.BILLING` permission and no purchase
  code in the APK at all; the price lives on the listing, not in the build. That is what
  keeps the "no network permission, nothing leaves your device" claim true of the *shipped
  artefact* rather than just the source. The rationale, the market anchors and the rejected
  alternatives are in [docs/MONETISATION.md](docs/MONETISATION.md). Verified against the
  rebuilt release APK: zero billing references, zero `INTERNET`, and the debug-only
  pseudo-locale correctly absent.

- **M8 — localisation groundwork.** Every user-visible string lives in
  `res/values/strings.xml` with real `<plurals>`, and an audit of the Compose sources found
  exactly one genuine miss (above). The debug build type enables
  `isPseudoLocalesEnabled`, so running it in English (XA) renders resource-backed text
  accented and bracketed while anything hardcoded looks normal — a mechanical way to catch
  the next one. Confirmed the pseudo-locale reaches the debug APK and not the release.
  Byte units and the timestamp pattern stay unlocalised on purpose, documented in the
  README along with the pseudo-locale check.

- **M7 — on-device validation.** The app was run on a real Xiaomi M2101K7AG (Android 12,
  MIUI V140) rather than only emulator images. Verified on hardware: the first-run
  permission prompt, "All files access" granted while the app is alive (picked up on
  resume), browsing real storage, the text editor's read *and* write path (the write
  checked independently with `adb shell cat`), the storage-usage screen, landscape layout,
  and **graceful degradation when access is revoked mid-use**. The findings live in
  [docs/EDGE_CASE_TESTING.md](docs/EDGE_CASE_TESTING.md), including what could *not* be
  driven from the host — long-press multi-select is delivered as a plain tap by this MIUI
  build, so the compress/extract buttons still want a manual pass.

- **M6 — release config and Play readiness.** An upload keystore (4096-bit RSA,
  `CN=Hadrian Burkhardt, L=Potsdam, C=DE`) is generated and wired through the git-ignored
  `keystore.properties`, so `bundleRelease` produces a signed, R8-minified, resource-shrunk
  `.aab` (4 682 814 bytes) and `assembleRelease` a signed APK. `docs/PLAY_RELEASE_CHECKLIST.md`
  walks the Play Console work, with step 4 covering the **Permissions Declaration Form** for
  "All files access" — the declaration a file manager must make, and the one that can block
  a release. `PRIVACY.md` is written to match the shipped permissions: no collection, no
  sharing, no `INTERNET`. The shipped permission set is audited from the release APK.

- **M5 — analysis, archives and viewers.** `domain/UsageAnalysis` rolls up recursive folder
  sizes and finds the largest files below a folder, which the new storage-usage screen
  shows as a size and a share bar per row. `domain/ArchiveEngine` creates ZIP archives and
  extracts ZIP, TAR, TAR.GZ, GZ, BZ2 and XZ using `java.util.zip` and Commons Compress —
  all pure Java, so the app still ships no native code; RAR and 7z are recognised and
  refused with a clear message rather than half-supported. Every archive entry name is
  passed through `core/ArchivePath` before it becomes a path, so a crafted `../` entry
  cannot write outside the destination. The browser gains Coil thumbnails in the list and
  grid, a built-in image viewer and text editor, and compress/extract actions. 26 new JVM
  tests (141 total), including a zip-slip archive that is refused while the same archive's
  safe entry still extracts.

- **M4 — the browser UI.** The app is now usable end to end. `StorageLocation` (with a
  real `StorageProvider` and a fake for tests) decides which backend is in effect;
  `BrowserViewModel` owns navigation, sorting, hidden files, list/grid, search, selection
  and the clipboard, and turns an `ASK` conflict into a prompt rather than a guess. The
  screen offers roots and folder lists with breadcrumbs, a details sheet, new-folder /
  rename / delete / conflict dialogs, and the "All files access" and SAF-folder prompts —
  including an upgrade banner so declining full access never blocks browsing. Deletes go
  through the platform's own confirmation when `MediaStore` can build one and fall back to
  a direct delete otherwise; a `FileProvider` lets other apps open and receive files
  without a `file://` URI ever leaving the process. 16 new JVM tests (115 total).

- **M3 — operations engine and foreground service.** `domain/FileOperations` turns the
  backend primitives into copy, move, delete and rename: it walks folders, counts the
  work up front so the progress bar has an honest denominator, checks for cancellation
  between entries (never swallowing `CancellationException`), and reports per-item
  failures instead of abandoning a batch because one file was unreadable. Conflicts are
  resolved through the M1 `TransferPlanner` — `ASK` is deliberately surfaced to the
  caller so the UI can prompt. A move tries the backend's atomic rename first and only
  falls back to copy-then-delete when the backend cannot do it (the SAF path across
  directories); the source is never deleted when its copy failed. `service/FileOpService`
  is a `dataSync` foreground service that mirrors the engine's progress into an ongoing
  notification, so a long operation survives the app being backgrounded. 23 new JVM
  tests (99 total), including Robolectric coverage of the notification and the service
  entering the foreground.

- **M2 — storage layer.** The two storage backends behind one interface. `AllFilesSource`
  is `java.io.File` over every mounted volume (the "All files access" path);
  `SafSource` is the Storage Access Framework fallback, reading a persisted tree URI
  through `DocumentsContract` with `SafDocumentIds` doing the tree↔path mapping and
  `SafGrant` owning the folder picker and its persistence. `VolumeRepository` enumerates
  volumes via `StorageManager`/`StorageVolume` and reports free/total space through
  `StatFs`; `StorageAccess` and `StorageAccessPolicy` decide between the two backends.
  Both sources confine their blocking I/O to `Dispatchers.IO` and expose a `suspend`
  contract. 32 new JVM tests (76 total), including a Robolectric run of `SafSource`
  against a stand-in `DocumentsProvider`.

- **M1 — pure-Kotlin core engine.** An Android-free `core/` package holding the logic
  every other layer builds on: `StoragePath` (normalised absolute paths that can never
  escape the root), `FileEntry` with extension-based `FileKind` classification and a
  `MimeTypes` lookup for "open with", natural-order `SortSpec` (directories always
  first, `file2` before `file10`), human-readable `FileSize`, `NameMatcher`
  (case-insensitive substring plus `*`/`?` globs), `NameAllocator` ("name (1)") and
  `TransferPlanner` (conflict policies and move-into-self detection). Covered by
  **44 JVM unit tests** across 10 classes.

- **M0 — project scaffold.** Gradle 9.3.1 / AGP 9.1.0 build with a version catalog,
  `de.softwareapp_hb.filemanager` app module, a Compose Material 3 shell with the
  branded blue theme (dynamic colour on Android 12+), an adaptive launcher icon, and
  the storage-access permission set (all files access + SAF fallback). Debug APK
  builds, installs and runs on an AOSP Android 12 AVD.