# mtgc — Personal Magic: The Gathering Library Catalog

A desktop and Android app (Tauri v2 + React) for cataloging your MTG
collection: rapid fuzzy card entry, rich criteria search (colors, commander
color-identity compatibility, mana value, type/subtype/keyword, price, format
legality), and deck organization with per-card deck membership. All logic lives
in a platform-agnostic Rust core, so both platforms share it.

## Architecture

```
src/                 React + TypeScript UI (swappable presentation)
src-tauri/           Tauri v2 shell — exposes the core as typed commands
crates/mtgc-core/    Pure Rust: db, fuzzy search, filters, decks, ingester, sync
crates/mtgc-server/  Optional sync server: each user's libraries, OIDC and/or passwords
```

Two kinds of data, both in the OS app-data dir (e.g.
`~/.local/share/com.garrettmills.mtgc/`):

- **your libraries** — owned cards, decks, deck contents. Each lives on the
  device and works fully offline; sign in to a sync server to share them
  between devices (see [Sync](#sync)). You can keep several and switch between
  them (see [Libraries](#libraries)). **Export library…** in the Info tab saves
  the open one as a JSON backup.
- **`reference.db`** — read-only card data built from Scryfall bulk. Bulky and
  re-downloaded per device, so it's never synced.

## First-time setup

```bash
./scripts/devel-setup.sh     # Tauri system libs (webkit2gtk/gtk3) + Tauri CLI
npm install                  # frontend deps
```

> **Why GTK3, not GTK4?** Tauri v2's Linux backend (`wry`/`tao`) hard-depends on
> GTK3 + `webkit2gtk-4.1`; there's no GTK4/webkitgtk-6.0 option yet. GTK4 support is
> tracked upstream but unmerged with no ETA:
> [tauri#7335](https://github.com/tauri-apps/tauri/issues/7335),
> [tao#1104](https://github.com/tauri-apps/tao/pull/1104),
> [wry#1228](https://github.com/tauri-apps/wry/issues/1228). Revisit once Tauri
> ships GTK4 support (likely Tauri v3).

## Run

```bash
cargo tauri dev              # launches the desktop app (dev mode)
```

On first launch, click **Download card data** — it fetches the Scryfall
*Oracle Cards* + *Default Cards* bulk (~a few hundred MB) and builds
`reference.db`. After that the app is fully offline.

You can also build the card database from the command line:

```bash
cargo run -p mtgc-core --bin mtgc-ingest -- /path/to/reference.db
```

## Production build

Build an optimized app with the frontend embedded into the executable:

```bash
./scripts/devel-setup.sh   # once, if not already done
cargo tauri build
```

Outputs (under the workspace `target/release/`):

- **`target/release/mtgc`** — the standalone executable. The web UI and all
  app logic are baked into this one file. It dynamically links the system WebKit/GTK
  libraries (`webkit2gtk4.1`, `gtk3`), so those must be present on the machine that
  runs it — they are on any modern desktop Linux and are installed by
  `devel-setup.sh`.
- **`target/release/bundle/rpm/*.rpm`** and **`.../deb/*.deb`** — native installers
  (Fedora / Debian-based) that add a menu entry and icon.

Useful variants:

```bash
cargo tauri build --no-bundle          # only the bare target/release/mtgc binary
```

Notes:

- The `mtgc` binary is a single file but relies on the system WebKit/GTK libs
  being present (installed by `devel-setup.sh`).
- The binary does **not** embed card data — first run still downloads the Scryfall
  bulk into the OS app-data dir. Your library lives there too; to share it
  between devices, see [Sync](#sync).
- The `[profile.release]` settings in `Cargo.toml` (strip + LTO) make the release
  build take a few minutes but keep the binary small.

### Distributing to Fedora (dnf repo)

Fedora machines get the app, and its updates, from a small dnf repo you host
yourself. `scripts/rpm-publish.sh` builds a signed RPM and adds it to the repo
in a directory you choose. It needs:

```bash
sudo dnf install rpm-sign createrepo_c
```

The first run also makes the package signing key. Give it the address the
directory will be served at:

```bash
RPM_REPO_URL=https://rpm.example.com/mtgc ./scripts/rpm-publish.sh --init-key ~/rpm-mtgc
```

After that, publishing is just:

```bash
./scripts/rpm-publish.sh ~/rpm-mtgc     # or: npm run rpm:publish -- ~/rpm-mtgc
```

Then, on each machine, add the repo once and install:

```bash
sudo dnf config-manager addrepo --from-repofile=https://rpm.example.com/mtgc/mtgc.repo
```

```bash
sudo dnf install mtgc
```

From then on, `sudo dnf upgrade` picks up new releases.

- **Serve the whole directory.** Unlike the F-Droid repo, nothing in it is
  secret. It holds the RPMs, the signed `repodata/`, the public key
  (`RPM-GPG-KEY-mtgc`) and `mtgc.repo`. The newest three versions are kept, so
  a bad release can be undone with `sudo dnf downgrade mtgc`.
- **Back up the signing key**, `~/.local/share/mtgc/gnupg`. It has no
  passphrase, so publishing runs unattended. Without it, each machine has to
  trust a new key before it takes another update.
- Versions work as on Android: `0.1.<commits on HEAD>`, see
  [Distributing to phones](#distributing-to-phones-f-droid).
- The RPM is built against this machine's libraries, so it installs on this
  Fedora release and newer.

### Distributing to Debian/Ubuntu (apt repo)

Debian-based machines get the app the same way, from an apt repo you host.
`scripts/deb-publish.sh` builds the `.deb` here on Fedora and adds it to the
repo in a directory you choose. It needs:

```bash
sudo dnf install reprepro dpkg
```

It signs with the same key as the dnf repo. If you haven't made that key yet,
pass `--init-key` the first time. Either way, give the first run the address
the directory will be served at:

```bash
DEB_REPO_URL=https://deb.example.com/mtgc ./scripts/deb-publish.sh ~/deb-mtgc
```

After that, publishing is just:

```bash
./scripts/deb-publish.sh ~/deb-mtgc     # or: npm run deb:publish -- ~/deb-mtgc
```

Then, on each machine, add the repo once and install:

```bash
sudo curl -fsSLo /etc/apt/sources.list.d/mtgc.sources https://deb.example.com/mtgc/mtgc.sources
```

```bash
sudo apt update && sudo apt install mtgc
```

From then on, `sudo apt upgrade` picks up new releases.

- **Serve the whole directory.** It holds `pool/`, the signed `dists/`, the
  public key (`mtgc.asc`) and `mtgc.sources`, which carries the key inline so
  machines don't need a separate keyring step. It also has a `README.html`
  with these install steps, for anyone who opens the address in a browser.
  `conf/` and `db/` are
  reprepro's own state; they're harmless to serve but aren't needed. The
  newest three versions are kept, so a bad release can be undone with
  `sudo apt install mtgc=<older version>`.
- Versions are the same as the RPM's. A build published with `--allow-dirty`
  gets a `~dirty` suffix, which apt sorts below the clean build of the same
  version.
- The `.deb` is built against this machine's libraries, so it needs a distro
  with at least this Fedora's glibc (2.43 on Fedora 44). Older Debian and
  Ubuntu releases can't install it.

### Distributing to Windows

The Windows installer is cross-built here on Linux and published to a plain
downloads folder you host. `scripts/windows-publish.sh` builds it through
[cargo-xwin](https://github.com/rust-cross/cargo-xwin) and needs, once:

```bash
sudo dnf install mingw-nsis-base llvm lld clang
```

```bash
cargo install --locked cargo-xwin
```

```bash
rustup target add x86_64-pc-windows-msvc
```

Then, for each release:

```bash
./scripts/windows-publish.sh ~/win-mtgc     # or: npm run windows:publish -- ~/win-mtgc
```

On Windows, download and run the setup.exe. A newer one upgrades the
installed app in place.

- **Serve the whole directory.** It holds the versioned installers
  (`mtgc_0.1.<n>_x64-setup.exe`, the newest three), `mtgc-latest-x64-setup.exe`
  as a stable link to the newest, and `SHA256SUMS`.
- Only the NSIS `setup.exe` can be built off Windows; an MSI needs WiX, which
  runs only on Windows. The first build downloads the MSVC CRT and Windows SDK
  into `~/.cache/cargo-xwin`.
- The installer isn't code-signed, so SmartScreen warns about an unknown
  publisher the first time: **More info → Run anyway**. It fetches WebView2 if
  the machine lacks it (Windows 10 and 11 normally ship it).
- Versions work as on Android: `0.1.<commits on HEAD>`, see
  [Distributing to phones](#distributing-to-phones-f-droid).

## Using it

- **Add Cards** — type a name (typos OK); ↑/↓ then Enter adds a copy.
- **Library** — filter owned cards by name, colors, commander identity (color
  identity ⊆ chosen), mana value, power/toughness, price, format legality,
  type/subtype/keyword, or deck. Hover a
  row's thumbnail for a full-size preview that tracks the cursor. Rows show which
  decks a card is in and a warning (⚠) when it's assigned to more decks than you
  own. Toggle **List / Tiles** (top-right) to switch between the table and a grid
  of full card images; the choice is remembered.
- **Card Search** — the same filters over *every* card, owned or not. Select
  rows (or tiles) and bulk-add them to a deck; one undo covers the whole batch.
- Deck contents offer the same List / Tiles toggle and hover previews.
- **Decks** — create decks and assign owned cards; set per-deck quantities.

Both filter panels share a row of quick toggles: hide **Universes Beyond**
(cards that exist only as another property — Lord of the Rings, Warhammer
40,000, Marvel), hide **digital-only** (Arena/MTGO cards such as Alchemy
rebalances), hide **Un-set** joke cards, or keep only cards that **can be a
commander**. The three exclusions are derived as *every* printing, so an
ordinary card reprinted into one of those sets — Lightning Bolt appears in
Marvel Commander — isn't hidden.

> Those three, plus the power/toughness filters, live in `reference.db`, which
> is rebuilt rather than migrated. After upgrading, click **Update card data**
> once to enable them; until then they're inert rather than broken. Price,
> format legality and *can be a commander* work immediately.

### Printings

The library counts cards, not printings, but you can say which printing a copy
is when it matters. Click a card's image in the **Library** or a deck to open
its preview. The **Owned** section lists your copies by printing and finish
(nonfoil / foil / etched), with a stepper for each, and **Add a printing…**
picks another. Copies you haven't assigned a printing to stay *unspecified*:
"5 copies · 3 by printing · 2 unspecified". Assigning more copies to printings
than you own raises the owned count to match. Lowering the owned count drops
the most recently added printing entries first.

In a deck, **Shown in this deck → Change…** picks which printing's art that
slot shows, and **Default** goes back to the usual one. This is display only:
it doesn't need to be a copy you own.

Decklist export writes a chosen or tracked printing the way Moxfield and Arena
do, and import reads it back:

```text
1 Sol Ring (2X2) 315 *F*
4 Lightning Bolt (2XM) 129
```

`*F*` marks foil and `*E*` etched. A library export writes one line per
printing, then a plain line for the unspecified copies. A suffix that doesn't
match any printing still imports the card itself.

**Library → Import cards…** also takes a **ManaBox** export of a collection
or binder, either the `.txt` or the `.csv`. Both add to what you already own.
The CSV names each copy's exact printing and finish, so it's the better of
the two. Condition, language, prices and the other ManaBox fields aren't
kept. Proxies count as owned copies. After you pick the file, the import asks
for a location to file the cards under, pre-filled with the file's name (a
ManaBox export is named after its binder). Leave it blank to keep cards'
current locations.

> The picker's dates and languages need card data from this version. Until you
> update it, printings are listed without them. Whenever your card data is
> missing something the app could use, a notice under the top bar offers
> **Update card data**, and **Import card data…** too on a phone. Dismissing it
> with **Not now** lasts until a later version needs something more.

## Libraries

Every device starts with one library, **Main**. To keep others alongside it —
a scratch library to try things in, a cube, a trade binder — click the
library name at the left of the top bar and choose **New library…**. The same
menu switches between them; **Info → Libraries** lists them all, and is where
you rename or delete them (on a phone, it's the only place).

Each library has its own cards and decks; the selected deck and the
"location" for new cards are remembered per library too. Card data is shared.

A new library can **sync** to your other devices or stay on this one. Synced
libraries appear on every signed-in device by themselves; one kept on this
device only never leaves it, which makes it the safe place to experiment.
The **Sync** checkbox in **Info → Libraries** changes your mind either way.

Deleting a synced library asks whether to **remove it from this device** (it
stays on the server and on your other devices, and this one stops downloading
it) or **delete it everywhere**. Other devices keep their copy of a library
deleted everywhere, marked as deleted from the server, until you remove it or
put it back. **Main** can be renamed but not deleted.

Libraries' files live in the app-data dir: **Main** where the one library
always lived, the others under `libraries/`.

## Sync

Your library always lives on the device you're using, so the app works the
same with or without a network. To keep several devices in step, run an
[mtgc sync server](#running-the-sync-server) and sign in to it from each one:
**Info → Sync server**, enter its address, and **Sign in…**. Sign-in happens
in your browser, on the server's own page — with a username and password, or
through your single sign-on provider, whichever the server offers — and the
browser hands the app back a token for that device alone.

Editing in two places merges rather than one side overwriting the other. Each
device remembers the last version of the library it knows the server had, and
merges three ways against it — which is what lets it tell "you changed this"
from "they deleted it": edit different cards on a phone offline and on the
desktop, and both survive. When both sides change the *same* field, the
server's value wins and the change is reported so you can correct it.

Sync runs by itself — at launch, on every switch away from and back to the app,
on reconnecting, and every few minutes while open. The top bar shows where it
stands (**Synced**, **Offline — changes will sync**, …); **Sync now** in the
Info tab forces a pass. Offline, edits simply wait on the device: nothing is
lost, and they go out with the next sync that reaches the server.

Each library syncs on its own: a library's edits never reach another one. An
older sync server keeps just one library per account, which **Main** syncs
with; update the server to sync the others.

The first time a device signs in to an account that already has a library,
and the device has one too, it asks whether to **combine** them (nothing from
either is lost) or **use the server's library** instead of this device's.

The Info tab also lists the account's signed-in devices, so a lost phone can be
signed out from another one.

> **Printings and older versions.** A library with printings in it (see
> [Printings](#printings)) is saved in a newer format. A device or server
> running an older version refuses it and says to update, rather than syncing
> and quietly losing them. Libraries that don't use printings stay readable by
> older versions. Update the sync server before the first device starts using
> printings.

> **Upgrading from folder sync?** Earlier versions kept the library as a JSON
> file in a folder your sync tool watched. Your library is already on each
> device, so signing in to a server picks up from there; the first device to
> sign in uploads it. If one device's copy is out of date, use **Import library
> file…** on it to combine in the `library.json` from the synced folder. Builds
> older still had you manage `library.db` yourself; the Info tab offers
> **Import old library** once for that.

## Running the sync server

`mtgc-server` is a single binary with a SQLite database, shipped as a
container image. Inside the container it listens on port 8080 and keeps its
database in `/data`; everything else is environment variables (below).

To run it locally, build the image, then run it with the port forwarded to
localhost and a named volume for the data:

```bash
docker build -f crates/mtgc-server/Dockerfile -t mtgc-sync-server .

docker run -d --name mtgc-sync-server \
  -p 127.0.0.1:8080:8080 \
  -v mtgc-sync-data:/data \
  -e MTGC_PUBLIC_URL=http://localhost:8080 \
  mtgc-sync-server

docker exec -it mtgc-sync-server mtgc-server user add yourname   # prompts for a password
```

Then sign in from the desktop app with `http://localhost:8080`. For more
settings, copy `crates/mtgc-server/deploy/.env.example` to `.env` beside it
(git ignores it) and pass `--env-file crates/mtgc-server/deploy/.env` instead
of the `-e`. Podman takes the same commands.

The container runs as UID 10001. A named volume, as above, picks up the right
ownership by itself; if you bind-mount a host directory instead, `chown 10001`
it first.

In production, put it behind something that terminates HTTPS — the Android
app refuses plain HTTP outside debug builds — and set `MTGC_PUBLIC_URL` to
the `https://` address users reach it at. On Kubernetes that means a
Deployment with **one replica** (it's a single SQLite file, so replicas can't
share it) and a `Recreate` strategy, a PersistentVolumeClaim mounted at
`/data`, a Service on port 8080, and an Ingress for TLS. `GET /healthz`
answers `ok` for probes. Keep `MTGC_OIDC_CLIENT_SECRET` in a Secret. Run the
account commands with `kubectl exec -it deploy/<name> -- mtgc-server user add
<name>`.

A freshly provisioned volume is usually owned by root, which the server
(UID/GID 10001) can't write to — it fails at startup with "`/data` isn't
writable". Have Kubernetes hand the volume to its group in the pod spec:

```yaml
spec:
  securityContext:
    runAsNonRoot: true
    runAsUser: 10001
    runAsGroup: 10001
    fsGroup: 10001
```

A few volume types ignore `fsGroup` (`hostPath`, and some NFS and local-path
provisioners). For those, `chown 10001:10001` the backing directory once, or
add an init container that does it.

To build the image and push it to Docker Hub
([`glmdev/mtgc`](https://hub.docker.com/r/glmdev/mtgc)):

```bash
npm run sync-server:build   # → docker.io/glmdev/mtgc:latest
npm run sync-server:push    # after `docker login docker.io`
```

Both call `scripts/sync-server-image.sh`. `IMAGE_TAG` overrides the `latest`
tag, `IMAGE_REPO` points it at another repository (e.g.
`IMAGE_REPO=registry.example.com/mtgc`), and `CONTAINER_ENGINE=podman` picks
podman when docker is also installed.

Configuration is all environment variables:

| Variable | Default | |
|---|---|---|
| `MTGC_PUBLIC_URL` | *(required)* | The `https://` address users reach the server at, exactly as the proxy serves it |
| `MTGC_BIND` | `0.0.0.0:8080` | Listen address |
| `MTGC_DB` | `mtgc-server.db` | SQLite database path |
| `MTGC_LOCAL_AUTH` | `true` | Username/password accounts |
| `MTGC_OIDC_ISSUER` | — | Turns on single sign-on, e.g. `https://auth.example.com/application/o/mtgc/` |
| `MTGC_OIDC_CLIENT_ID`, `MTGC_OIDC_CLIENT_SECRET` | — | A confidential client, with redirect URI `${MTGC_PUBLIC_URL}/auth/callback` |
| `MTGC_OIDC_NAME` | `single sign-on` | Shown on the button: "Sign in with …" |
| `MTGC_OIDC_SCOPES` | `openid email profile` | |
| `MTGC_ALLOWED_EMAILS` | — | Comma-separated allow list of verified emails; unset leaves it to the provider |

With both sign-in methods on, the sign-in page offers both; with only single
sign-on, it goes straight to the provider. Each provider identity and each
local account is its own user with its own library.

Local accounts are managed from the command line; there's no sign-up page, so
a server on the internet can't be filled with accounts by strangers:

```bash
mtgc-server user add <name> [--display-name <text>]   # prompts for a password
mtgc-server user passwd <name>
mtgc-server user remove <name> --yes                  # also deletes their server-side library
mtgc-server user list
```

The server keeps the last 50 versions of each library in its database
(`library_history`) as a safety net for recovering by hand.

## Develop / test

```bash
cargo test -p mtgc-core      # core: db, search, filters, decks, ingest, sync merge + cycle
cargo test -p mtgc           # shell: config, merge-base storage, sign-in listener
cargo test -p mtgc-server    # server: sign-in, compare-and-swap, devices, end-to-end sync
npm run build                # typecheck + build frontend
cargo build                  # build everything incl. the desktop app
```

The sync merge is a pure function over plain structs (`mtgc_core::sync::merge3`),
and the sync cycle runs over a `Remote` trait (`mtgc_core::sync::remote`), so the
cases that matter — concurrent edits, a delete racing an edit, a lost reply, a
lost write race — are unit tests rather than something you have to reproduce
across two devices. `crates/mtgc-server/tests/sync_e2e.rs` then runs two
devices against the real server over HTTP.

To try sign-in by hand, run a server locally (`MTGC_PUBLIC_URL=http://127.0.0.1:8080
cargo run -p mtgc-server`, after `cargo run -p mtgc-server -- user add me`) and
sign in from the app with that address. From the Android emulator, the host is
`http://10.0.2.2:8080`; debug builds allow plain HTTP.

To typecheck the Android Kotlin without building the APK (it doesn't invoke
cargo, so it won't disturb a running dev session):

```bash
cd src-tauri/gen/android && ./gradlew :app:compileUniversalDebugKotlin
```

## Android

The Rust core and frontend are platform-agnostic, so the Android build shares
all app logic with the desktop; only data provisioning and file access differ.

### One-time setup

Install Android Studio and **launch it once** so its wizard downloads the SDK,
then:

```bash
./scripts/android-setup.sh
```

That adds what Android Studio doesn't install by default: the SDK
command-line tools, a pinned stable **NDK**, and the Rust Android targets. It
prints the three environment variables to export (`ANDROID_HOME`, `NDK_HOME`,
`JAVA_HOME`).

> **Why the NDK?** `mtgc-core` builds `rusqlite` with the `bundled` feature
> (compiles SQLite from C) and `rustls` pulls in `ring` (C/asm), so a C
> cross-toolchain is required. The bundled SQLite can't be swapped for
> Android's system libsqlite3 either — the card schema needs FTS5 with the
> `trigram` tokenizer, which platform SQLite often lacks.

> **Why `JAVA_HOME`?** The Android build (Gradle 9.6, AGP 9) runs on JDK 17
> through 25. The script prefers Android Studio's bundled JetBrains Runtime,
> then the newest system JDK in that range, and skips anything newer than 25
> until it's been tested.

### Build and run

Every Android command needs `ANDROID_HOME` / `NDK_HOME` / `JAVA_HOME`. Source
the helper once per shell — it auto-detects all three:

```bash
source scripts/android-env.sh      # bash / zsh
```

```fish
source scripts/android-env.fish    # fish
```

Only the env helper is shell-specific (it has to mutate the calling shell);
`android-setup.sh` is executed rather than sourced, so it works from any shell.

Then, from the project root:

```bash
cargo tauri android dev --open   # dev server + open in Android Studio
cargo tauri android build --apk  # standalone release APK
```

`src-tauri/gen/android` is committed (unlike the rest of `gen/`) because
`AndroidManifest.xml` is hand-edited — Android permissions have no
`tauri.conf.json` equivalent.

### Working in Android Studio

Use **`cargo tauri android dev --open`** rather than opening
`src-tauri/gen/android` directly. Studio's Run button delegates the Rust build
to `cargo tauri android android-studio-script`, which expects a running Tauri
dev session — it reads the dev-server address from
`/tmp/<identifier>-server-addr`. Open the Gradle project on its own and the
build fails with `failed to read missing addr file`.

With the dev session running, Studio's device dropdown, Device Manager
(emulator), and debugger all work normally.

> **JetBrains Toolbox users:** `--open` finds Studio by scanning XDG data dirs
> for a `.desktop` entry whose `Name` is *exactly* `Android Studio`. Toolbox
> writes a versioned name instead (e.g. `Android Studio Quail 2 2026.1.2 Patch
> 1`), so the lookup misses and the launch fails with a confusing
> `Cmd(["Android Studio"]) ... No such file or directory`. `android-setup.sh`
> drops in a hidden shim entry (`~/.local/share/applications/android-studio.desktop`)
> to fix this; delete that file to undo it.

To build without Studio and without a dev server, use `cargo tauri android
build` — that path needs no addr file.

### Distributing to phones (F-Droid)

Releases go out through a small F-Droid repo you host yourself: add it to the
F-Droid app once, and every new build then shows up there as an update.
`scripts/fdroid-publish.sh` builds a signed arm64 APK and adds it to the repo
in a directory you choose. It needs fdroidserver:

```bash
pipx install fdroidserver
```

The first run also makes the app's signing key and the repo. Give it the
address the repo will be served at:

```bash
FDROID_REPO_URL=https://fdroid.example.com/repo ./scripts/fdroid-publish.sh --init-keystore ~/fdroid-mtgc
```

After that, publishing is just:

```bash
./scripts/fdroid-publish.sh ~/fdroid-mtgc     # or: npm run android:publish -- ~/fdroid-mtgc
```

It ends by printing the repo address with its fingerprint
(`https://…/repo?fingerprint=…`); add that in F-Droid under **Settings →
Repositories**.

- **Serve only `~/fdroid-mtgc/repo`** (and `archive/`, which holds older
  versions, if you like) — any static file server will do. Never serve the
  directory itself: it holds the repo signing key (`keystore.p12`) and its
  password (`config.yml`).
- **Back up both keys**: `~/.local/share/mtgc/android-release.jks` with
  `src-tauri/gen/android/keystore.properties` (the app key and its password),
  and the repo directory's `keystore.p12` with `config.yml`. Android only
  installs an update signed with the same key as the installed app, so
  without the app key every phone would have to uninstall and reinstall.
- **Versions are automatic.** The Android versionCode is the number of commits
  on `HEAD`, and the version shown is `0.1.<that count>`, e.g. `0.1.47`, so
  any commit can ship without a bump. The major and minor come from
  `tauri.conf.json`. That's also why pushed history shouldn't be
  rewritten. The script won't publish uncommitted changes without
  `--allow-dirty`, or a versionCode the repo already has.
- A phone with a debug build, or anything signed with another key, has to
  uninstall it before F-Droid can install the release, and uninstalling
  deletes the app's data. Sync or **Export library…** first.

Without `keystore.properties`, `cargo tauri android build` still produces an
unsigned APK as before.

### Card data on a phone

Downloading card data streams ~740MB of JSON to build a ~73MB database, which
is slow on mobile and may be killed if the app is backgrounded. Faster: copy
`reference.db` from a desktop install onto the device and use **Import card
data…**. The file is validated before it replaces anything.

### Sync on Android

Signing in works as on desktop: the browser opens the server's sign-in page,
and returns to the app through the `mtgc://` URL scheme (registered by the
deep-link plugin from `plugins.deep-link` in `tauri.conf.json`). The app needs
no storage permission — the library lives in its private storage, and syncing
is network only.

## Branding

The logo is an original pirate-ship silhouette in the terracotta brand color
(`#C8553D`) — a nod to the MTG card "Pirate Ship", not a reproduction of its
art. Source: `src-tauri/icons/logo-source.svg`. To regenerate the full
platform icon set after editing it:

```bash
cargo tauri icon src-tauri/icons/logo-source.svg
```