Add XaiImageGenService

Author: Madzionator

src/MaIN.Services/Services/ImageGenServices/XaiImageGenService.cs

@@ -0,0 +1,112 @@
+using MaIN.Domain.Configuration;
+using MaIN.Domain.Entities;
+using MaIN.Services.Constants;
+using MaIN.Services.Services.Abstract;
+using MaIN.Services.Services.Models;
+using System.Net.Http.Headers;
+using System.Net.Http.Json;
+using System.Text.Json;
+
+namespace MaIN.Services.Services.ImageGenServices;
+
+public class XaiImageGenService(
+    IHttpClientFactory httpClientFactory,
+    MaINSettings settings)
+    : IImageGenService
+{
+    private readonly IHttpClientFactory _httpClientFactory = httpClientFactory ?? throw new ArgumentNullException(nameof(httpClientFactory));
+    private readonly MaINSettings _settings = settings ?? throw new ArgumentNullException(nameof(settings));
+
+    public async Task<ChatResult?> Send(Chat chat)
+    {
+        var client = _httpClientFactory.CreateClient(ServiceConstants.HttpClients.XaiClient);
+        string apiKey = _settings.XaiKey ?? Environment.GetEnvironmentVariable("XAI_API_KEY") ??
+            throw new InvalidOperationException("xAI Key not configured");
+
+        client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", apiKey);
+        var requestBody = new
+        {
+            model = string.IsNullOrWhiteSpace(chat.Model) ? Models.GROK_IMAGE : chat.Model,
+            prompt = BuildPromptFromChat(chat),
+            n = 1,
+            response_format = "b64_json" //or "url"
+        };
+
+        using var response = await client.PostAsJsonAsync(ServiceConstants.ApiUrls.XaiImageGenerations, requestBody);
+        var imageBytes = await ProcessXaiResponse(response);
+        return CreateChatResult(imageBytes);
+    }
+
+    private static string BuildPromptFromChat(Chat chat)
+    {
+        return chat.Messages
+            .Select((msg, index) => index == 0 ? msg.Content : $"&& {msg.Content}")
+            .Aggregate((current, next) => $"{current} {next}");
+    }
+
+    private async Task<byte[]> ProcessXaiResponse(HttpResponseMessage response)
+    {
+        response.EnsureSuccessStatusCode();
+        var responseData = await response.Content.ReadFromJsonAsync<XaiImageResponse>(new JsonSerializerOptions{ PropertyNamingPolicy = JsonNamingPolicy.SnakeCaseLower });
+
+        var first = responseData?.Data.FirstOrDefault()
+                    ?? throw new InvalidOperationException("No image data returned from xAI");
+
+        if (!string.IsNullOrEmpty(first.B64Json))
+        {
+            return Convert.FromBase64String(first.B64Json);
+        }
+
+        if (!string.IsNullOrEmpty(first.Url))
+        {
+            return await DownloadImageAsync(first.Url);
+        }
+
+        throw new InvalidOperationException("No image content returned from xAI");
+    }
+
+    private async Task<byte[]> DownloadImageAsync(string imageUrl)
+    {
+        var imageClient = _httpClientFactory.CreateClient(ServiceConstants.HttpClients.ImageDownloadClient);
+
+        using var imageResponse = await imageClient.GetAsync(imageUrl);
+        imageResponse.EnsureSuccessStatusCode();
+
+        return await imageResponse.Content.ReadAsByteArrayAsync();
+    }
+
+    private static ChatResult CreateChatResult(byte[] imageBytes)
+    {
+        return new ChatResult
+        {
+            Done = true,
+            Message = new Message
+            {
+                Content = ServiceConstants.Messages.GeneratedImageContent,
+                Role = ServiceConstants.Roles.Assistant,
+                Image = imageBytes,
+                Type = MessageType.Image
+            },
+            Model = Models.GROK_IMAGE,
+            CreatedAt = DateTime.UtcNow
+        };
+    }
+
+    private struct Models
+    {
+        public const string GROK_IMAGE = "grok-2-image";
+    }
+}
+
+
+file class XaiImageResponse
+{
+    public XaiImageData[] Data { get; set; } = [];
+}
+
+file class XaiImageData
+{
+    public string? Url { get; set; }
+    public string? B64Json { get; set; }
+    public string? RevisedPrompt { get; set; }
+}

src/MaIN.Services/Services/LLMService/Factory/ImageGenServiceFactory.cs

@@ -18,6 +18,8 @@ public class ImageGenServiceFactory(IServiceProvider serviceProvider) : IImageGe
             BackendType.DeepSeek => null,
             BackendType.GroqCloud => null,
             BackendType.Anthropic => null,
+            BackendType.Xai => new XaiImageGenService(serviceProvider.GetRequiredService<IHttpClientFactory>(),
+                serviceProvider.GetRequiredService<MaINSettings>()),
             BackendType.Self => new ImageGenService(serviceProvider.GetRequiredService<IHttpClientFactory>(),
                 serviceProvider.GetRequiredService<MaINSettings>()),