Refactor user context handling with CurrentUserService

Introduced ICurrentUserService and its implementation to centralize retrieval of the current user's ID from claims. Updated FriendsController to use this service instead of direct claim access. Registered the service and IHttpContextAccessor in DI. Added integration tests for FriendsController. Moved UsernameValidator to Infrastructure/Validators.

Govor.API.Tests/IntegrationTests/Controllers/AuthControllerTests.cs

@@ -86,9 +86,9 @@ public class AuthControllerTests
         var result = await _controller.Register(request);
 
         // Assert
-        Assert.That(result, Is.InstanceOf<BadRequestObjectResult>());
-        var badRequestResult = result as BadRequestObjectResult;
-        Assert.That(badRequestResult.Value, Is.EqualTo("Invite link invalid."));
+        Assert.That(result, Is.InstanceOf<NotFoundObjectResult>());
+        var notFoundObjectResult = result as NotFoundObjectResult;
+        Assert.That(notFoundObjectResult.Value, Is.EqualTo("Invite link invalid."));
     }
 
     [Test]

Govor.API.Tests/IntegrationTests/Controllers/FriendsControllerTests.cs

@@ -0,0 +1,115 @@
+using AutoFixture;
+using Govor.API.Controllers;
+using Govor.Application.Exceptions.FriendsService;
+using Govor.Application.Interfaces;
+using Govor.Application.Interfaces.Infrastructure.Extensions;
+using Govor.Contracts.DTOs;
+using Govor.Core.Models;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Logging;
+using Moq;
+
+namespace Govor.API.Tests.IntegrationTests.Controllers;
+
+[TestFixture]
+public class FriendsControllerTests
+{
+    private Fixture _fixture;
+    private Mock<ILogger<FriendsController>> _loggerMock;
+    private Mock<IFriendsService> _friendsServiceMock;
+    private Mock<ICurrentUserService> _currentUserServiceMock;
+    private FriendsController _controller;
+    
+    [SetUp]
+    public void SetUp()
+    {
+        _fixture = new Fixture();
+        _fixture.Behaviors.OfType<ThrowingRecursionBehavior>().ToList().ForEach(b => _fixture.Behaviors.Remove(b));
+        _fixture.Behaviors.Add(new OmitOnRecursionBehavior());
+        
+        _loggerMock = new Mock<ILogger<FriendsController>>();
+        _friendsServiceMock = new Mock<IFriendsService>();
+        _currentUserServiceMock = new Mock<ICurrentUserService>();
+        
+        _controller = new FriendsController(
+            _loggerMock.Object,
+            _friendsServiceMock.Object,
+            _currentUserServiceMock.Object
+        );
+    }
+    
+    // Tests for Search action 
+    [Test]
+    public async Task Search_ValidRequest_ReturnsOkResult()
+    {
+        var users = _fixture.CreateMany<User>().ToList();
+        var userId = _fixture.Create<Guid>();
+        var query = _fixture.Create<string>();
+        
+        _currentUserServiceMock.Setup(c => c.GetCurrentUserId()).Returns(userId);
+        
+        _friendsServiceMock.Setup(f => f.SearchUsersAsync(query, userId))
+            .ReturnsAsync(users);
+        
+        // Act 
+        var result = await _controller.Search(query);
+        
+        var okResult = result as OkObjectResult;
+        dynamic value = okResult.Value;
+        
+        List<UserDto> userDtos = value as List<UserDto>;
+        
+        // Assert 
+        Assert.That(value, Is.Not.Null);
+        Assert.That(value.Count, Is.EqualTo(users.Count));
+        Assert.That(userDtos.Select(u => u.Id), Is.EqualTo(users.Select(u => u.Id)));
+    }
+
+    [Test]
+    public async Task Search_InvalidQuery_BadRequest()
+    {
+        // Act 
+        var result = await _controller.Search(string.Empty);
+        // Assert
+        Assert.That(result, Is.InstanceOf<BadRequestObjectResult>());
+        var badRequestResult = result as BadRequestObjectResult;
+        Assert.That(badRequestResult.Value, Is.EqualTo("Query cannot be empty"));
+    }
+    
+    
+    [Test]
+    public async Task Search_NotFound_IfThrowsSearchUsersException()
+    {
+        // Arrange 
+        _friendsServiceMock.Setup(f => f.SearchUsersAsync(It.IsAny<string>(), It.IsAny<Guid>()))
+            .ThrowsAsync(new SearchUsersException(_fixture.Create<string>()));
+        
+        // Act 
+        var result = await _controller.Search(_fixture.Create<string>());
+        // Assert
+        Assert.That(result, Is.InstanceOf<NotFoundObjectResult>());
+    }
+    
+    [Test]
+    public async Task Search_StatusCode500_IfThrowsSomeException()
+    {
+        // Arrange 
+        _friendsServiceMock.Setup(f => f.SearchUsersAsync(It.IsAny<string>(), It.IsAny<Guid>()))
+            .ThrowsAsync(new Exception(_fixture.Create<string>()));
+        
+        // Act 
+        var result = await _controller.Search(_fixture.Create<string>());
+        // Assert
+        Assert.That(result, Is.InstanceOf<ObjectResult>());
+        var objectResult = result as ObjectResult;
+        Assert.That(objectResult.StatusCode, Is.EqualTo(500));
+    }
+
+    
+    
+    [TearDown]
+    public void TearDown()
+    {
+        _controller.Dispose();
+    }
+}