#!/bin/bash

# Run a command as the unprivileged rootless Docker install user.
#
# This used to ssh to <user>@localhost to get a fully-initialised user session
# (so `systemctl --user` and the rootless dockerd would work). That needs an SSH
# server, a generated key and authorized_keys — none of which the install set
# up, so the whole rootless path silently no-op'd. Instead run via `sudo -u`
# with the session env set explicitly: `loginctl enable-linger` (done during
# rootless setup) keeps the user's `systemd --user` and /run/user/<uid> alive,
# so `systemctl --user` works, and DOCKER_HOST points at the rootless socket.
# `sudo -u` to an unprivileged user is not a root escalation, and there's no SSH
# attack surface.
dockerCommandRunInstallUser()
{
    local silent_flag=""
    if [ "$1" == "--silent" ]; then
        silent_flag="$1"
        shift
    fi
    local remote_command="$1"

    local uid
    uid=$(id -u "$CFG_DOCKER_INSTALL_USER" 2>/dev/null)
    if [ -z "$uid" ]; then
        isError "Cannot run as '$CFG_DOCKER_INSTALL_USER' — user does not exist."
        return 1
    fi

    # rootless docker installs its binaries to the user's ~/bin, so include it.
    local run_env=(
        "HOME=/home/$CFG_DOCKER_INSTALL_USER"
        "XDG_RUNTIME_DIR=/run/user/$uid"
        "DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/$uid/bus"
        "DOCKER_HOST=unix:///run/user/$uid/docker.sock"
        "PATH=/home/$CFG_DOCKER_INSTALL_USER/bin:/usr/bin:/bin:/usr/local/bin"
    )

    if [ -n "$silent_flag" ]; then
        sudo -u "$CFG_DOCKER_INSTALL_USER" env "${run_env[@]}" bash -c "$remote_command" >/dev/null 2>&1
    else
        sudo -u "$CFG_DOCKER_INSTALL_USER" env "${run_env[@]}" bash -c "$remote_command"
    fi
}
