Added authentication and authorization, updated dependency injections, removed hard-coded connection string

SchengenVisaApi/ApplicationLayer/AuthServices/LoginService/LoginService.cs

@@ -0,0 +1,21 @@
+using ApplicationLayer.AuthServices.LoginService.Exceptions;
+using ApplicationLayer.AuthServices.NeededServices;
+using ApplicationLayer.AuthServices.Requests;
+
+namespace ApplicationLayer.AuthServices.LoginService
+{
+    /// <inheritdoc cref="ILoginService"/>
+    public class LoginService(IUsersRepository users, ITokenGenerator tokenGenerator) : ILoginService
+    {
+        async Task<string> ILoginService.LoginAsync(UserLoginRequest request, CancellationToken cancellationToken)
+        {
+            var user = await users.FindByEmailAsync(request.Email, cancellationToken);
+            if (user is null || user.Password != request.Password)
+            {
+                throw new IncorrectLoginDataException();
+            }
+
+            return tokenGenerator.CreateToken(user);
+        }
+    }
+}