@pytest.fixture(scope="session")
def gcs_emulator() -> Generator[tuple[str, int], None, None]:
    # port=0 -> run on a random open port; though we have to lookup later.
    server = gcp_storage_emulator.server.create_server("localhost", 0, in_memory=True)
    server.start()
    try:
        host, port = server._api._httpd.socket.getsockname()
        with mock.patch.dict(os.environ, {"STORAGE_EMULATOR_HOST": f"http://{host}:{port}"}):
            yield host, port
    finally:
        server.stop()

@pytest.fixture(scope="session")
def gcs_emulator(
    fake_gcs_server_version: str = "1.37.0", port: int = 2784
) -> Generator[str, None, None]:
    if not sh.which("docker"):
        raise pytest.skip("docker not available to run fake-gcs-server")
    container = "arti-test-gcs-emulator"
    url = f"http://localhost:{port}"
    sh.docker.run(
        "-d",
        f"--name={container}",
        f"-p={port}:{port}",
        f"fsouza/fake-gcs-server:{fake_gcs_server_version}",
        "-backend=memory",
        "-scheme=http",
        f"-external-url={url}",
        f"-port={port}",
        f"-public-host={url}",
    )
    try:
        time.sleep(0.25)
        requests.get(url + "/storage/v1/b").raise_for_status()
        with mock.patch.dict(os.environ, {"STORAGE_EMULATOR_HOST": url}):
            yield url
    finally:
        sh.docker.rm("-fv", container)

MACHINE_MAP = {
    "aarch64": "arm64",
    "arm64": "arm64",
    "x86_64": "amd64",
}
BIN_CACHE_DIR = Path(__file__).parent / ".bin_cache"
BIN_MACHINE = MACHINE_MAP[platform.machine()]
BIN_SYSTEM = platform.system()


def _get_fake_gcs_server_cmd(
    machine: str = BIN_MACHINE, system: str = BIN_SYSTEM, version: str = "1.37.0"
) -> sh.Command:
    binpath = BIN_CACHE_DIR / f"fake-gcs-server-{version}-{system}-{machine}"
    if not binpath.exists():
        tgz_name = f"{binpath}.tgz"
        url = f"https://github.com/fsouza/fake-gcs-server/releases/download/v{version}/fake-gcs-server_{version}_{system}_{machine}.tar.gz"
        with requests.get(url, stream=True) as resp:
            if resp.status_code != requests.codes.ok:
                pytest.skip(f"fake-gcs-server for {system} {machine} is not available")
            with open(tgz_name, "wb") as tgz:
                shutil.copyfileobj(resp.raw, tgz)
        sh.tar("-xf", tgz_name, "fake-gcs-server")
        sh.mv("fake-gcs-server", binpath)
        sh.rm(tgz_name)
    return sh.Command(binpath)


@pytest.fixture(scope="session")
def gcs_emulator(port: int = 2784) -> Generator[str, None, None]:
    url = f"http://localhost:{port}"
    fake_gcs_server_proc = _get_fake_gcs_server_cmd()(
        "-backend=memory",
        "-scheme=http",
        f"-external-url={url}",
        f"-port={port}",
        f"-public-host={url}",
        _bg=True,
    )
    try:
        time.sleep(0.25)
        requests.get(url + "/storage/v1/b").raise_for_status()
        with mock.patch.dict(os.environ, {"STORAGE_EMULATOR_HOST": url}):
            yield url
    finally:
        fake_gcs_server_proc.terminate()
        fake_gcs_server_proc.wait()