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public class FormatterUplink : PayloadFormatter.IFormatterUplink
{
    public JObject Evaluate(IDictionary<string, string> properties, string application, string terminalId, DateTime timestamp, byte[] payloadBytes)
    {
        JObject telemetryEvent = new JObject();

        if (payloadBytes is null)
        {
            return telemetryEvent;
        }

        telemetryEvent.Add("SequenceNumber", BitConverter.ToUInt16(payloadBytes));

        JObject location = new JObject();

        double latitude = BitConverter.ToInt32(payloadBytes, 2) / 10000000.0;
        location.Add("lat", latitude);

        double longitude = BitConverter.ToInt32(payloadBytes, 6) / 10000000.0;
        location.Add("lon", longitude);

        location.Add("alt", 0);

        telemetryEvent.Add("DeviceLocation", location);

        UInt32 packetimestamp = BitConverter.ToUInt32(payloadBytes, 10);

        DateTime fixAtUtc = DateTime.UnixEpoch.AddSeconds(packetimestamp);

        telemetryEvent.Add("FixAtUtc", fixAtUtc);

        properties.Add("iothub-creation-time-utc", fixAtUtc.ToString("s", CultureInfo.InvariantCulture));

        return telemetryEvent;
    }
}

private static void ApplicationCore(CommandLineOptions options)
{
    Dictionary<string, string> properties = new Dictionary<string, string>();

    Console.WriteLine($"Uplink formatter file:{options.FormatterPath}");

    PayloadFormatter.IFormatterUplink evalulatorUplink;
    try
    {
        evalulatorUplink = CSScript.Evaluator.LoadFile<PayloadFormatter.IFormatterUplink>(options.FormatterPath);
    }
    catch (CSScriptLib.CompilerException cex)
    {
        Console.Write($"Loading or compiling file:{options.FormatterPath} failed Exception:{cex}");
        return;
    }

    byte[] payloadBytes;
    try
    {
        payloadBytes = Convert.FromHexString(options.PayloadHex);
    }
    catch (FormatException fex)
    {
        Console.WriteLine("Convert.FromHexString failed:{0}", fex.Message);
        return;
    }

    DateTime timeStamp;
    if (options.TimeStamp.HasValue)
    {
        timeStamp = options.TimeStamp.Value;
    }
    else
    {
        timeStamp = DateTime.UtcNow;
    }

    JObject telemetryEvent;

    try
    {
        telemetryEvent = evalulatorUplink.Evaluate(properties, options.Application, options.TerminalId, timeStamp, payloadBytes);
    }
    catch (Exception ex)
    {
        Console.WriteLine($"evalulatorUplink.Evaluate failed Exception:{ex}");
        return;
    }

    telemetryEvent.TryAdd("Application", options.Application);
    telemetryEvent.TryAdd("TerminalId", options.TerminalId);
    if ( options.TimeStamp.HasValue)
    {
        telemetryEvent.TryAdd("TimeStamp", options.TimeStamp.Value.ToString("s", CultureInfo.InvariantCulture));
    }
    telemetryEvent.TryAdd("DataLength", payloadBytes.Length);
    telemetryEvent.TryAdd("Data", Convert.ToHexString( payloadBytes));

    Console.WriteLine("Properties:");
    foreach (var property in properties)
    {
        Console.WriteLine($"{property.Key}:{property.Value}");
    }
    Console.WriteLine("");

    Console.WriteLine("JSON Telemetry event payload");
    Console.WriteLine(telemetryEvent.ToString(Formatting.Indented));
}