UI/logic updates, tests added, backend updated

Seasoned.Tests/RecipeServiceTests.cs

@@ -0,0 +1,70 @@
+using Moq;
+using Xunit;
+using FluentAssertions;
+using Microsoft.Extensions.Configuration;
+using Microsoft.AspNetCore.Http;
+using Seasoned.Backend.Services;
+using Seasoned.Backend.DTOs;
+using System.Text;
+
+namespace Seasoned.Tests;
+
+public class RecipeServiceTests
+{
+    private readonly Mock<IConfiguration> _mockConfig;
+    private readonly RecipeService _service;
+
+    public RecipeServiceTests()
+    {
+        _mockConfig = new Mock<IConfiguration>();
+        // Mock the API Key retrieval
+        _mockConfig.Setup(c => c["GEMINI_API_KEY"]).Returns("fake-api-key-123");
+
+        _service = new RecipeService(_mockConfig.Object);
+    }
+
+    [Fact]
+    public void Constructor_ThrowsException_WhenApiKeyIsMissing()
+    {
+        // Arrange
+        var emptyConfig = new Mock<IConfiguration>();
+        emptyConfig.Setup(c => c["GEMINI_API_KEY"]).Returns((string?)null);
+
+        // Act
+        Action act = () => new RecipeService(emptyConfig.Object);
+
+        // Assert
+        act.Should().Throw<ArgumentNullException>().WithMessage("*API Key missing*");
+    }
+
+    [Fact]
+    public async Task ParseRecipeImageAsync_ReturnsError_WhenImageIsEmpty()
+    {
+        // Arrange: Create an empty file
+        var fileMock = new Mock<IFormFile>();
+        fileMock.Setup(f => f.Length).Returns(0);
+
+        // Act & Assert
+        var result = await _service.ParseRecipeImageAsync(fileMock.Object);
+        
+        result.Should().NotBeNull();
+    }
+
+    [Fact]
+    public void ParseRecipeImageAsync_AttachesCorrectBase64Header()
+    {
+        // Arrange
+        var content = "fake-image-data";
+        var fileName = "test.png";
+        var ms = new MemoryStream(Encoding.UTF8.GetBytes(content));
+        var mockFile = new FormFile(ms, 0, ms.Length, "image", fileName)
+        {
+            Headers = new HeaderDictionary(),
+            ContentType = "image/png"
+        };
+
+        var resultImageUrl = $"data:{mockFile.ContentType};base64,{Convert.ToBase64String(ms.ToArray())}";
+        
+        resultImageUrl.Should().StartWith("data:image/png;base64,");
+    }
+}