using MxGateway.Client;

namespace MxGateway.Client.Cli;

public static class MxGatewayClientCli
{
    public static int Run(
        string[] args,
        TextWriter standardOutput,
        TextWriter standardError)
    {
        ArgumentNullException.ThrowIfNull(args);
        ArgumentNullException.ThrowIfNull(standardOutput);
        ArgumentNullException.ThrowIfNull(standardError);

        if (args.Length is 0 || IsHelp(args[0]))
        {
            WriteUsage(standardOutput);
            return 0;
        }

        if (string.Equals(args[0], "version", StringComparison.OrdinalIgnoreCase))
        {
            standardOutput.WriteLine(
                $"gateway-protocol={MxGatewayClientContractInfo.GatewayProtocolVersion}");
            standardOutput.WriteLine(
                $"worker-protocol={MxGatewayClientContractInfo.WorkerProtocolVersion}");
            return 0;
        }

        standardError.WriteLine($"Unknown command '{args[0]}'.");
        WriteUsage(standardError);
        return 2;
    }

    private static bool IsHelp(string value)
    {
        return string.Equals(value, "-h", StringComparison.OrdinalIgnoreCase)
            || string.Equals(value, "--help", StringComparison.OrdinalIgnoreCase)
            || string.Equals(value, "help", StringComparison.OrdinalIgnoreCase);
    }

    private static void WriteUsage(TextWriter writer)
    {
        writer.WriteLine("mxgw-dotnet version");
        writer.WriteLine("mxgw-dotnet --help");
    }
}