Build a Voice Agent with C#

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using Deepgram;
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using Deepgram.Logger;
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using Deepgram.Models.Authenticate.v1;
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using Deepgram.Models.Agent.v2.WebSocket;
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using System.Collections.Generic;
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using System.Net.Http;
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namespace SampleApp
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{
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    class Program
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    {
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        static async Task Main(string[] args)
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        {
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            try
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            {
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                Deepgram.Library.Initialize(LogLevel.Debug);
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                var apiKey = Environment.GetEnvironmentVariable("DEEPGRAM_API_KEY");
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                DeepgramWsClientOptions options = new DeepgramWsClientOptions(null, null, true);
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                var agentClient = ClientFactory.CreateAgentWebSocketClient(apiKey, options);
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                var lastAudioTime = DateTime.Now;
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                var audioFileCount = 0;
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                var settingsConfiguration = new SettingsSchema();
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                settingsConfiguration.Agent.Think.Provider.Type = "open_ai";
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                settingsConfiguration.Agent.Think.Provider.Model = "gpt-4o-mini";
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                settingsConfiguration.Audio.Output.SampleRate = 24000;
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                settingsConfiguration.Audio.Output.Container = "wav";
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                settingsConfiguration.Audio.Input.SampleRate = 24000;
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                settingsConfiguration.Agent.Greeting = "Hello, how can I help you today?";
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                settingsConfiguration.Agent.Listen.Provider.Type = "deepgram";
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                settingsConfiguration.Agent.Listen.Provider.Model = "nova-3";
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                settingsConfiguration.Agent.Speak.Provider.Type = "deepgram";
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                settingsConfiguration.Agent.Speak.Provider.Model = "aura-2-thalia-en";
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                bool connected = await agentClient.Connect(settingsConfiguration);
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                if (!connected)
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                {
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                    Console.WriteLine("Failed to connect to Deepgram WebSocket server.");
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                    return;
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                }
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                await agentClient.Subscribe(new EventHandler<AudioResponse>((sender, e) =>
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                {
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                    if (DateTime.Now.Subtract(lastAudioTime).TotalSeconds > 7)
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                    {
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                        audioFileCount++;
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                        using (BinaryWriter writer = new BinaryWriter(File.Open($"output_{audioFileCount}.wav", FileMode.Create)))
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                        {
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                            writer.Write(CreateWavHeader(24000, 16, 1));
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                        }
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                    }
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                    if (e.Stream != null)
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                    {
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                        using (BinaryWriter writer = new BinaryWriter(File.Open($"output_{audioFileCount}.wav", FileMode.Append)))
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                        {
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                            writer.Write(e.Stream.ToArray());
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                        }
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                    }
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                    lastAudioTime = DateTime.Now;
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                }));
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                string url = "https://dpgr.am/spacewalk.wav";
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                using (var httpClient = new HttpClient())
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                {
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                    var response = await httpClient.GetAsync(url);
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                    var stream = await response.Content.ReadAsStreamAsync();
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                    var buffer = new byte[8192];
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                    int bytesRead;
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                    while ((bytesRead = await stream.ReadAsync(buffer, 0, buffer.Length)) > 0)
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                    {
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                        var chunk = new byte[bytesRead];
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                        Array.Copy(buffer, chunk, bytesRead);
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                        await agentClient.SendBinaryImmediately(chunk);
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                    }
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                }
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                Console.WriteLine("Press any key to exit...");
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                Console.ReadKey();
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                await agentClient.Stop();
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                Deepgram.Library.Terminate();
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            }
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            catch (Exception ex)
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            {
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                Console.WriteLine($"Exception: {ex.Message}");
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            }
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        }
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        static byte[] CreateWavHeader(int sampleRate, short bitsPerSample, short channels)
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        {
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            int byteRate = sampleRate * channels * (bitsPerSample / 8);
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            short blockAlign = (short)(channels * (bitsPerSample / 8));
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            byte[] header = new byte[44];
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            header[0] = 0x52; // R
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            header[1] = 0x49; // I
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            header[2] = 0x46; // F
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            header[3] = 0x46; // F
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            header[8] = 0x57; // W
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            header[9] = 0x41; // A
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            header[10] = 0x56; // V
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            header[11] = 0x45; // E
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            header[12] = 0x66; // f
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            header[13] = 0x6D; // m
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            header[14] = 0x74; // t
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            header[15] = 0x20; // Space
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            header[16] = 0x10; // Subchunk1Size
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            header[20] = 0x01; // AudioFormat
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            header[22] = (byte)channels;
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            header[24] = (byte)(sampleRate & 0xFF);
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            header[25] = (byte)((sampleRate >> 8) & 0xFF);
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            header[26] = (byte)((sampleRate >> 16) & 0xFF);
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            header[27] = (byte)((sampleRate >> 24) & 0xFF);
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            header[28] = (byte)(byteRate & 0xFF);
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            header[29] = (byte)((byteRate >> 8) & 0xFF);
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            header[30] = (byte)((byteRate >> 16) & 0xFF);
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            header[31] = (byte)((byteRate >> 24) & 0xFF);
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            header[32] = (byte)blockAlign;
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            header[34] = (byte)bitsPerSample;
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            header[36] = 0x64; // d
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            header[37] = 0x61; // t
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            header[38] = 0x74; // t
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            header[39] = 0x61; // a
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            return header;
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        }
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    }
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}