INC-1 add start logic for login

src/main/java/ru/soune/no_copy/service/AuthService.java

@@ -5,6 +5,8 @@ import org.springframework.context.MessageSource;
 import org.springframework.security.crypto.password.PasswordEncoder;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
+import ru.soune.no_copy.dto.LoginRequest;
+import ru.soune.no_copy.dto.LoginResponse;
 import ru.soune.no_copy.dto.RegisterRequest;
 import ru.soune.no_copy.entity.AuthToken;
 import ru.soune.no_copy.entity.User;
@@ -13,8 +15,10 @@ import ru.soune.no_copy.repository.AuthTokenRepository;
 import ru.soune.no_copy.repository.UserRepository;
 
 import java.security.SecureRandom;
+import java.time.LocalDateTime;
 import java.util.HexFormat;
 import java.util.Locale;
+import java.util.Optional;
 
 @Service
 @RequiredArgsConstructor
@@ -51,6 +55,39 @@ public class AuthService {
         return authTokenRepository.save(authToken);
     }
 
+    public LoginResponse login(LoginRequest request) {
+        Optional<User> userOpt = userRepository.findByEmail(request.getEmail());
+        if (userOpt.isEmpty()) {
+            //ADD EXCEPTION
+        }
+
+        User user = userOpt.get();
+
+        if (!passwordEncoder.matches(request.getPassword(), user.getPassword())) {
+            //ADD EXCEPTION
+        }
+
+        String token = generateToken();
+        LocalDateTime expiresAt = LocalDateTime.now().plusDays(30);
+
+        AuthToken authToken = new AuthToken();
+        authToken.setToken(generateToken());
+        authToken.setUser(user);
+
+        authTokenRepository.save(authToken);
+
+        userRepository.save(user);
+
+        LoginResponse response = new LoginResponse();
+        response.setSuccess(true);
+//        response.setMessage(""); add message
+        response.setUser(user);
+        response.setToken(token);
+        response.setExpiresAt(expiresAt.toString());
+
+        return response;
+    }
+//TODO change logic generate token
     private String generateToken() {
         byte[] bytes = new byte[32];
         new SecureRandom().nextBytes(bytes);