package com.ecommerce.service;

import com.ecommerce.dto.request.UpdateProfileRequest;
import com.ecommerce.dto.response.UserResponse;
import com.ecommerce.exception.ResourceNotFoundException;
import com.ecommerce.model.User;
import com.ecommerce.repository.UserRepository;
import lombok.RequiredArgsConstructor;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

@Service
@RequiredArgsConstructor
public class UserService {
    
    private final UserRepository userRepository;
    
    public User getCurrentUser() {
        String email = SecurityContextHolder.getContext().getAuthentication().getName();
        return userRepository.findByEmail(email)
                .orElseThrow(() -> new ResourceNotFoundException("User", "email", email));
    }
    
    public UserResponse getCurrentUserProfile() {
        return UserResponse.fromUser(getCurrentUser());
    }
    
    @Transactional
    public UserResponse updateProfile(UpdateProfileRequest request) {
        User user = getCurrentUser();
        
        if (hasValue(request.getFirstName())) {
            user.setFirstName(request.getFirstName());
        }
        if (hasValue(request.getLastName())) {
            user.setLastName(request.getLastName());
        }
        if (request.getPhone() != null) {
            user.setPhone(request.getPhone());
        }
        if (hasValue(request.getProfileImage())) {
            user.setProfileImage(request.getProfileImage());
        }
        
        // Update address - always update if any address field is provided
        User.Address address = user.getAddress();
        if (address == null) {
            address = new User.Address();
        }
        
        if (request.getStreet() != null) address.setStreet(request.getStreet());
        if (request.getCity() != null) address.setCity(request.getCity());
        if (request.getState() != null) address.setState(request.getState());
        if (request.getZipCode() != null) address.setZipCode(request.getZipCode());
        if (request.getCountry() != null) address.setCountry(request.getCountry());
        
        user.setAddress(address);
        
        user = userRepository.save(user);
        return UserResponse.fromUser(user);
    }
    
    private boolean hasValue(String value) {
        return value != null && !value.trim().isEmpty();
    }
    
    // Admin methods
    public Page<UserResponse> getAllUsers(Pageable pageable) {
        return userRepository.findAll(pageable).map(UserResponse::fromUser);
    }
    
    public UserResponse getUserById(String userId) {
        User user = userRepository.findById(userId)
                .orElseThrow(() -> new ResourceNotFoundException("User", "id", userId));
        return UserResponse.fromUser(user);
    }
    
    public void toggleUserStatus(String userId) {
        User user = userRepository.findById(userId)
                .orElseThrow(() -> new ResourceNotFoundException("User", "id", userId));
        user.setActive(!user.isActive());
        userRepository.save(user);
    }
    
    public UserResponse updateUserRole(String userId, String role) {
        User user = userRepository.findById(userId)
                .orElseThrow(() -> new ResourceNotFoundException("User", "id", userId));
        
        user.getRoles().clear();
        user.getRoles().add(User.Role.valueOf(role.toUpperCase()));
        
        // Ensure USER role is always present
        if (!user.getRoles().contains(User.Role.USER)) {
            user.getRoles().add(User.Role.USER);
        }
        
        user = userRepository.save(user);
        return UserResponse.fromUser(user);
    }
    
    public void activateUser(String userId) {
        User user = userRepository.findById(userId)
                .orElseThrow(() -> new ResourceNotFoundException("User", "id", userId));
        user.setActive(true);
        userRepository.save(user);
    }
    
    public void deactivateUser(String userId) {
        User user = userRepository.findById(userId)
                .orElseThrow(() -> new ResourceNotFoundException("User", "id", userId));
        user.setActive(false);
        userRepository.save(user);
    }
}