backend/buisnesslogic/src/main/java/com/plannaplan/services/UserService.java

package com.plannaplan.services;

import java.util.List;
import java.util.Optional;
import java.util.UUID;

import com.plannaplan.entities.User;
import com.plannaplan.exceptions.UserNotFoundException;
import com.plannaplan.repositories.UserRepository;
import com.plannaplan.types.UserRoles;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

/**
 *  Service of UserService which can get(By Email), login, save user.
 */
@Service
public class UserService {
    @Autowired
    private UserRepository repo;

    public UserService() {
        super();
    }

    public User checkForUser(String email, String usosId) {
        if (usosId == null) {
            Optional <User> user = this.repo.getByAuthority(email.replace("\n", "").trim()); 
            if (user.isPresent()){
                return user.get();
            }
            else {
                final User newUser = new User(null,null,email.replace("\n", "").trim(),UserRoles.STUDENT);
                this.repo.save(newUser);
                return newUser;
            }
        }
        else {
            Optional <User> user = this.repo.getByUsosId(usosId.replace("\n", "").trim());
            if (user.isPresent()){
                return user.get();
            }
            else {
                final User newUser = new User(null,null,email.replace("\n", "").trim(),usosId,UserRoles.STUDENT);
                this.repo.save(newUser);
                return newUser;
            }
        }
    }

    public String login(String authority) throws UserNotFoundException {
        User user = this.repo.getByAuthority(authority.replace("\n", "").trim())
                .orElseThrow(() -> new UserNotFoundException("Can not find user with given authority"));

        final String token = UUID.randomUUID().toString();
        user.setToken(token);
        this.repo.save(user);
        return token;
    }

    public User save(User user) {
        return this.repo.save(user);
    }

    public User getUserByEmail(String email) throws UserNotFoundException {
        return this.repo.getByAuthority(email.replace("\n", "").trim())
                .orElseThrow(() -> new UserNotFoundException("Cannot find user with given authority"));

    }

    public Optional<User> getByToken(String token) {
        return this.repo.getByToken(token);
    }

    public List<User> searchForStudents(String query) {
        return this.repo.searchForUsers(query, UserRoles.STUDENT);
    }

    public Optional<User> getById(Long userId) {
        return this.repo.findById(userId);
    }

}