# PhoneBridge (CLI prototype)

PhoneBridge is a working local-network HTTP file bridge: point it at a file
or folder and it starts a small HTTP server on your computer that your
phone's browser can open over the same Wi-Fi to download it (or, in reverse,
open a page on your phone and upload a file straight back to your computer)
— no cable, no companion app, no pairing, no cloud account required. This
is a genuine, dependency-free technique for quick phone-computer hand-offs.
Real iPhone/Android device-protocol transfer (MTP for Android, AFC/iTunes
protocol for iOS), messages/photos/music export, and full device-to-device
migration from the original product concept all require platform-specific
device libraries/drivers that cannot be implemented as a portable, stdlib-only
Go CLI — those remain on the roadmap. See ../plan.md for the full product
plan.

## Build from source

Requires Go 1.24+, no external dependencies.

    go build -o phonebridge .

Cross-compile for another platform:

    GOOS=windows GOARCH=amd64 go build -o phonebridge.exe .
    GOOS=darwin  GOARCH=arm64 go build -o phonebridge .

## Usage

  phonebridge send <path> [--port 0] [--once] [--host <addr>]

    Serves a file or a directory over HTTP so your phone can download it.
    A single file is served directly at "/" (and "/<filename>") using
    http.ServeFile, which correctly supports HTTP Range requests (resumable
    downloads) and sets the right Content-Type. A directory is served with
    an auto-generated HTML index page listing every file with a download
    link, using http.FileServer, which also supports Range/resume for each
    file. --port 0 (the default) lets the OS pick a free port; the actual
    bound port is detected and printed. --once shuts the server down
    automatically right after the first successful full download completes
    (handy for a single one-off hand-off); without it, the server runs
    until you press Ctrl+C, printing a line for every request as it
    completes. --host overrides the auto-detected LAN address printed in
    the URL (see below).

  phonebridge receive <destdir> [--port 0] [--once] [--host <addr>]

    Starts a server with a minimal upload form at "/" (a plain HTML file
    input posting multipart/form-data to "/upload"). Files POSTed to
    "/upload" are saved into <destdir> (created automatically if it
    doesn't exist), and a confirmation page is returned. --once shuts the
    server down after the first successful upload; otherwise it runs until
    interrupted, printing each received file's name and size as it lands.
    --port and --host behave the same as for "send".

    An upload never replaces a file that is already in <destdir>. Phones
    reuse filenames constantly (IMG_0001.JPG, image.jpg), so when the name
    is taken the file is saved under the next free variation of it —
    "photo.jpg", then "photo (2).jpg" — and the name actually used is
    printed along with the reason. Files are opened O_EXCL, so replacing an
    existing file is not something this command can do, with or without a
    flag.

  phonebridge help

LAN address detection: PhoneBridge picks the first non-loopback IPv4
address from net.InterfaceAddrs() as a best-effort guess at your LAN IP.
On machines with multiple network interfaces (VPNs, virtual adapters,
multiple NICs) this heuristic can pick the wrong one — pass --host with
your phone-reachable IP to override it. If no non-loopback address is
found at all, PhoneBridge falls back to 127.0.0.1 and prints a clear
warning rather than crashing (that fallback is only reachable from the
same machine, not from a phone).

Security note: this opens an unauthenticated HTTP server on your LAN for
as long as it runs — anyone on the same network can reach the URL while
it's up. That's fine for a quick hand-off on a trusted home network; use
--once or stop the server with Ctrl+C promptly, and don't leave it running
on a shared or untrusted network.

## Prebuilt binaries

See ../downloads/ for prebuilt binaries (Windows/macOS/Linux) and
CHECKSUMS.txt for their SHA-256 hashes. These are unsigned indie builds —
Windows SmartScreen and macOS Gatekeeper will warn on first run, which is
expected until a code-signing certificate is in place.