Index: iknow-api/Services/Implementations/AuthService.cs
===================================================================
--- iknow-api/Services/Implementations/AuthService.cs	(revision fc7b4b415ad1cd1dbbc022b043e8fa579443f7f7)
+++ iknow-api/Services/Implementations/AuthService.cs	(revision fc7b4b415ad1cd1dbbc022b043e8fa579443f7f7)
@@ -0,0 +1,79 @@
+using System.IdentityModel.Tokens.Jwt;
+using System.Security.Claims;
+using System.Text;
+using BCrypt.Net;
+using FinXaccesApi.Controllers;
+using iknow_api.Core.Models;
+using FinXaccesApi.DTOs;
+using FinXaccesApi.Repositories;
+using Microsoft.IdentityModel.Tokens;
+
+namespace FinXaccesApi.Services
+{
+    public class AuthService : IAuthService
+    {
+        private readonly IUserRepository _userRepository;
+        private readonly IConfiguration _configuration;
+
+        public AuthService(IUserRepository userRepository, IConfiguration configuration)
+        {
+            _userRepository = userRepository;
+            _configuration = configuration;
+        }
+
+        public async Task<bool> RegisterAsync(UserDto userDto)
+        {
+            if (await _userRepository.UserExistsAsync(userDto.Username))
+                return false;
+
+            var user = new User
+            {
+                Email = userDto.Username,
+                PasswordHash = BCrypt.Net.BCrypt.HashPassword(userDto.Password)
+            };
+
+            await _userRepository.AddUserAsync(user);
+            return true;
+        }
+
+        public async Task<string?> LoginAsync(UserDto userDto)
+        {
+            var user = await _userRepository.GetUserByUsernameAsync(userDto.Username);
+            if (user == null || !BCrypt.Net.BCrypt.Verify(userDto.Password, user.PasswordHash))
+                return null;
+
+            return CreateToken(user);
+        }
+
+        public async Task<int> GetUsersCountAsync()
+        {
+            return await _userRepository.GetUsersCountAsync();
+        }
+
+        private string CreateToken(User user)
+        {
+            var claims = new[]
+            {
+                new Claim("id", user.Id.ToString()),
+                new Claim("username", user.Email)
+            };
+
+            var keyString = _configuration["Jwt:Key"];
+            if (string.IsNullOrEmpty(keyString))
+                throw new Exception("JWT Key is missing in configuration!");
+
+            var key = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(keyString));
+            var creds = new SigningCredentials(key, SecurityAlgorithms.HmacSha256);
+
+            var token = new JwtSecurityToken(
+                issuer: "finxacces-api",
+                audience: "finxacces-api",
+                claims: claims,
+                expires: DateTime.Now.AddHours(1),
+                signingCredentials: creds
+            );
+
+            return new JwtSecurityTokenHandler().WriteToken(token);
+        }
+    }
+}