miniSCP/README.md

# miniSCP

A cross-platform, dual-panel SFTP/local file manager — a small WinSCP-style
commander built on **Bun**, **Electrobun**, and **Angular**.

Each of the two panels independently shows either the local filesystem or a
remote server over SSH/SFTP, so you can move files **local↔remote**,
**remote↔remote**, or **local↔local** through one symmetric engine.

> **Name & icon are placeholders.** See [Rebranding](#rebranding) — it's a
> one-file change.

## Features

- Dual-panel commander UI; either panel can be Local or any saved connection.
- **Session tabs**: each tab is an independent left/right workspace; remote
  sessions stay connected and transfers keep running in background tabs.
- Per-panel action toolbar with a direction-explicit copy button, plus a
  VSCode-style status bar showing live transfer progress (click to expand the
  transfer queue with per-file speed and ETA).
- **Overwrite confirmation** on name collisions, with a source-vs-destination
  comparison (size, modified date, which is newer) and batch replace-all /
  skip-all.
- **Settings** (gear, top-right): light / dark / system theme and speed units
  (MB/s or Mbps), persisted across restarts.
- On macOS the tab bar is fused with the window titlebar; other platforms keep
  a standard titlebar.
- **Menu-bar (tray) icon**: template icon that adapts to light/dark; click it
  to bring the app to the front.
- **Edit files** (F4 / toolbar / File menu): a built-in editor works on local
  and remote files directly; or pick an external app (Options → Editor →
  Custom → Choose…). External edits of remote files download to a temp folder,
  are watched, and every save auto-uploads (visible in the transfer list) until
  the session disconnects. Leftover temp files from a crash are offered for
  cleanup at the next start.
- Browse, sort (name/size/modified, folders first), keyboard navigation.
- Create folder / file, rename, delete (recursive), change permissions (chmod).
- Upload, download, and remote→remote copy — files **and** whole folders —
  with a transfer queue, per-job progress, and cancel.
- Connection manager: saved connections organised into folders, password or
  private-key auth (with passphrase).

## Stack

| Layer      | Choice                                                        |
| ---------- | ------------------------------------------------------------- |
| Runtime    | Bun (main process, all SSH/SFTP + file IO)                    |
| Desktop    | Electrobun 1.18 (native webview, typed RPC bridge)            |
| Frontend   | Angular 22 (standalone, signals, zoneless) in `ui/`           |
| Styling    | Tailwind CSS v4, shadcn-style tokens (no component library)   |
| Icons      | @ng-icons/mynaui                                              |
| SSH/SFTP   | `ssh2` (pure-JS under Bun)                                    |

The repo is a Bun workspace: the Electrobun app at the root, the Angular app in
`ui/`. Shared types and the RPC contract live in `src/shared/` and are imported
by both sides.

```
src/shared/     types.ts, rpc.ts (wire contract), branding.ts
src/bun/        Electrobun main process
  fs/           FileSystemProvider + LocalProvider + SftpProvider + registry
  transfers/    engine.ts (queue/stream copy) + walk.ts (recursive helpers)
  store/        connections.json persistence
ui/src/app/     Angular components + signal services
```

## Prerequisites

- [Bun](https://bun.sh) ≥ 1.3 (`bun --version`).
- macOS: **Xcode Command Line Tools** (for the app build).
- No Node install required — a preload shim (`scripts/node-version-shim.ts`)
  satisfies the Angular CLI's Node version check while running under Bun.

## Setup

```bash
bun install          # installs root + ui workspace deps
```

## Develop

```bash
bun run dev
```

This starts the Angular dev server (hot reload for UI code) and launches the
Electrobun app pointed at it. Edits under `ui/` reload instantly; edits to the
Bun main process (`src/bun/**`, RPC schema) trigger an app relaunch.

## Build a packaged app

```bash
bun run build        # ng build (ui/dist) + electrobun build -> build/*/miniSCP*.app
```

The Angular bundle is copied into the app under `views://app`. The macOS icon is
compiled from `assets/icon.iconset` into `AppIcon.icns` automatically.

For a distributable (optimized, with auto-update channel) build, use
`bunx electrobun build --env=stable` (see the
[Electrobun docs](https://framework.blackboard.sh/electrobun/) for signing,
notarization, and release hosting).

## Rebranding

Everything user-facing reads from **[`src/shared/branding.ts`](src/shared/branding.ts)**:

```ts
export const BRANDING = {
  appName: "miniSCP",          // window title, bundle name, app-data folder
  identifier: "es.teknes.miniscp",
  legacyNames: ["BunSCP"],     // previous names; their data dirs migrate on boot
  version: "0.1.0",
  icon: "assets/icon.iconset",
} as const;
```

To change the icon: edit `assets/logo.svg` (app icon) and
`assets/tray/tray-glyph.svg` (menu-bar glyph), then run
`bun scripts/gen-icons.ts` — it regenerates the macOS iconset, `icon.png`, the
tray template image, and the tray progress frames from the SVGs
(`@resvg/resvg-js`, dev-only dependency).

> Renaming `appName` changes the app-data directory. Add the old name to
> `legacyNames` and the app moves the previous folder (connections, settings,
> edit temp files) into place on the next boot.

## Where connections are stored

Saved connections live in a plain JSON file in the OS app-data directory
(macOS: `~/Library/Application Support/miniSCP/connections.json`), written with
`0600` permissions.

> ⚠️ **Passwords are stored in plaintext** in this file (a deliberate v1
> simplicity choice). Anyone who can read the file can read the passwords. If
> that isn't acceptable for your use, use key-based auth or don't save the
> password (connect ad-hoc). OS-keychain storage is a natural future addition.

## Keyboard shortcuts

`Tab` switch panel · `↑`/`↓`/`PgUp`/`PgDn`/`Home`/`End` move cursor ·
`Space` select · `Enter` open folder · `Backspace` parent ·
`Ctrl/Cmd+A` select all · `F5` copy to other panel · `F2` rename ·
`F7` new folder · `F8`/`Delete` delete · `Cmd/Ctrl+T` new tab ·
`Cmd/Ctrl+W` close tab · `Ctrl+Tab` next tab.

(On Macs, function keys may need `fn` — every action also has a toolbar button.)

## Same-file protection

Copying a file or folder onto itself would truncate it to zero bytes (the
destination is opened for writing before the source is read). miniSCP blocks
this at several layers:

- **Same session / same host**: every connection carries a filesystem identity
  (`local`, or `resolvedIP:port` — the hostname is DNS-resolved, so
  `myserver.lan` and its IP compare equal even across two panels/tabs holding
  separate SSH sessions to the same server). Equal identity + equal or nested
  paths ⇒ the transfer is refused before anything is opened.
- **Hidden aliases** (two *different* addresses that reach the same machine —
  NAT, split DNS): when identities differ but source and destination paths
  collide anyway, a probe file is written through one connection and looked up
  through the other; if it's visible on both, they're the same machine and the
  copy is refused. (SFTP offers no device/inode identity — the mechanism
  `cp`/`rsync` use locally — so probing is the only deterministic test.)
- The overwrite dialog never offers to "Replace" a file with itself — such
  items are auto-skipped with a notice.

**Known residual limitation**: the same filesystem mounted at *different
paths* on two connections (bind mounts, NFS exported twice, shared container
volumes) cannot be detected — the paths differ, so no guard or probe triggers.
Be careful when two panels reach the same data through different mount points.

## Portability notes

Platform seams are isolated behind `process.platform` / `PLATFORM` branches
marked with `PORTABILITY:` comments: editor launch (`open` / `cmd /c start` /
`xdg-open`), app pickers, owner/group lookups, tray images, window chrome,
shell-integration wording, drive listing, and the connections-file ACL. The
application menu ([src/bun/menu.ts](src/bun/menu.ts)) is macOS-only for now;
the in-app UI covers every menu action.

## Windows (beta)

Windows 11+ x64 is supported as a **beta** target (win-arm64 deferred). All
electrobun APIs the app uses are implemented on Windows; known issues are
upstream:

- **HiDPI blur** ([electrobun#324](https://github.com/blackboardsh/electrobun/issues/324)):
  WebView2 renders at 1x on scaled displays until upstream adds DPI awareness.
- **Notifications** use legacy balloon style, not Windows toast.
- **Unsigned binaries**: both the Setup.exe installer and the portable exe
  trigger SmartScreen/Mark-of-the-Web warnings on first run. No Start Menu
  entry or uninstaller (installer unpacks to `%LOCALAPPDATA%`).
- `connections.json` is protected with an `icacls` current-user ACL instead of
  POSIX 0600 (which is meaningless on Windows).

First-Windows-boot smoke test: drives dropdown lists C:\ etc.; navigate to a
drive root ('..' disappears); local↔remote transfers; external editor launch
(`cmd /c start`) and the .exe picker; Show in Explorer / Recycle Bin; tray icon
renders colored; Permissions absent on local panels; Ctrl+labels in tooltips;
portable zip runs from any folder.

## Known issues

- **Rare native crash under load.** A long-running session (multiple remote
  connections, extended uptime) can hit a Bun panic — a segfault inside Bun
  1.3.13's FFI thread-safe callbacks executing Electrobun's native→worker
  bridge (`FFI_Callback_threadsafe_call` → `web_worker.spin` in the decoded
  crash report). This is an upstream Bun × Electrobun bug, not app code; a
  restart recovers cleanly and in-flight work isn't corrupted. Expected to
  resolve when Electrobun bumps its pinned Bun (currently 1.3.13; 1.3.14+
  available). Bun's own crash reporter link is printed to the console on panic.

## Not in v1

Drag-and-drop, file preview/edit, transfer resume, symlink following
(symlinks are listed but skipped by transfers), OS keychain, tab persistence
across restarts, Windows/Linux packaging (the code is portable; only macOS
packaging is wired up).