using AS1024.Wireguard.Utils;

const string Help =
    """
    wgkey - WireGuard key utility

    wgkey gen
    wgkey pub    <private-base64>
    wgkey decode <key-base64>
    """;

if (args.Length == 0 || args[0] is "-h" or "--help" or "help")
{
    Console.WriteLine(Help);
    return 0;
}

try
{
    // TODO: stdin mode?
    switch (args[0])
    {
        case "gen":
        {
            var priv = WireGuardKeyUtils.GeneratePrivateKey();
            var pub  = WireGuardKeyUtils.GetPublicKey(priv);
            Console.WriteLine($"private={Convert.ToBase64String(priv)}");
            Console.WriteLine($"public={Convert.ToBase64String(pub)}");
            return 0;
        }
        case "pub" when args.Length == 2:
            Console.WriteLine(Convert.ToBase64String(
                WireGuardKeyUtils.GetPublicKey(WireGuardKeyUtils.FromBase64(args[1]))));
            return 0;
        case "decode" when args.Length == 2:
            Console.WriteLine(Convert.ToHexString(WireGuardKeyUtils.FromBase64(args[1])).ToLowerInvariant());
            return 0;
        default:
            Console.Error.WriteLine(Help);
            return 1;
    }
}
catch (Exception e) when (e is ArgumentException or FormatException)
{
    Console.Error.WriteLine(e.Message);
    return 1;
}