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src/main/java/mate/academy/dao/UserDao.java

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+package mate.academy.dao;
+
+import mate.academy.model.User;
+
+import java.util.Optional;
+
+public interface UserDao {
+    User save(User user);
+
+    User get(Long id);
+
+    Optional<User> findByEmail(String email);
+}

src/main/java/mate/academy/dao/impl/UserDaoImpl.java

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+package mate.academy.dao.impl;
+
+import mate.academy.dao.UserDao;
+import java.util.Optional;
+import mate.academy.model.User;
+import mate.academy.util.HibernateUtil;
+import org.hibernate.Session;
+import org.hibernate.Transaction;
+import org.hibernate.query.Query;
+
+public class UserDaoImpl implements UserDao {
+    @Override
+    public User save(User user) {
+        Session session = null;
+        Transaction transaction = null;
+        try {
+            session = HibernateUtil.getSessionFactory().openSession();
+            transaction = session.beginTransaction();
+            session.save(user);
+            transaction.commit();
+            return user;
+        } catch (Exception exception) {
+            if (transaction != null) {
+                transaction.rollback();
+            }
+            throw new RuntimeException("Cannot save user", exception);
+        } finally {
+            if (session != null) {
+                session.close();
+            }
+        }
+    }
+
+    @Override
+    public User get(Long id) {
+        try (Session session = HibernateUtil.getSessionFactory().openSession()) {
+            return session.get(User.class, id);
+        } catch (Exception exception) {
+            throw new RuntimeException("Cannot get user", exception);
+        }
+    }
+
+    @Override
+    public Optional<User>  findByEmail(String email) {
+        try (Session session = HibernateUtil.getSessionFactory().openSession()) {
+            Query<User> query = session.createQuery("from User where email"
+                    + "=:email", User.class);
+            query.setParameter("email", email);
+            return query.uniqueResultOptional();
+        } catch (Exception exception) {
+            throw new RuntimeException("Cannot get user", exception);
+        }
+    }
+}

src/main/java/mate/academy/exception/AuthenticationException.java

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+package mate.academy.exception;
+
+public class AuthenticationException extends Exception {
+    public AuthenticationException(String message) {
+        super(message);
+    }
+}

src/main/java/mate/academy/exception/RegistrationException.java

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+package mate.academy.exception;
+
+public class RegistrationException extends Exception {
+    public RegistrationException(String message) {
+        super(message);
+    }
+}

src/main/java/mate/academy/model/User.java

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+package mate.academy.model;
+
+import jakarta.persistence.*;
+
+@Entity
+public class User {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+    @Column(unique = true)
+    private String email;
+    private String password;
+    @Column(columnDefinition = "BLOB")
+    private byte[] salt;
+
+    public byte[] getSalt() {
+        return salt;
+    }
+
+    public void setSalt(byte[] salt) {
+        this.salt = salt;
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    public String getPassword() {
+        return password;
+    }
+
+    public void setPassword(String password) {
+        this.password = password;
+    }
+
+    @Override
+    public String toString() {
+        return "User{"
+                + "id=" + id
+                + ", email='" + email
+                + '}';
+    }
+}

src/main/java/mate/academy/security/AuthenticationService.java

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+package mate.academy.security;
+
+import mate.academy.exception.AuthenticationException;
+import mate.academy.exception.RegistrationException;
+import mate.academy.model.User;
+
+public interface AuthenticationService {
+    User login(String email, String password) throws AuthenticationException;
+
+    User register(String email, String password) throws RegistrationException;
+}

src/main/java/mate/academy/security/impl/AuthenticationServiceImpl.java

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+package mate.academy.security.impl;
+
+import mate.academy.exception.AuthenticationException;
+import mate.academy.exception.RegistrationException;
+import mate.academy.lib.Inject;
+import mate.academy.model.User;
+import mate.academy.security.AuthenticationService;
+import mate.academy.service.UserService;
+import mate.academy.util.HashUtil;
+import java.util.Optional;
+
+public class AuthenticationServiceImpl implements AuthenticationService {
+    @Inject
+    private UserService userService;
+
+    @Override
+    public User login(String email, String password) throws AuthenticationException {
+        Optional<User> byEmail = userService.findByEmail(email);
+        if (byEmail.isEmpty()) {
+            throw new AuthenticationException("Invalid email");
+        }
+        User user = byEmail.get();
+        String hashedPassword = HashUtil.hashPassword(password, user.getSalt());
+        if (!hashedPassword.equals(user.getPassword())) {
+            throw new AuthenticationException("Invalid password or email");
+        }
+        return user;
+    }
+
+    @Override
+    public User register(String email, String password) throws RegistrationException {
+        if (!userService.findByEmail(email).isEmpty()){
+            throw new RegistrationException("During registration, check that the email is unique (i.e., not already used)");
+        }
+        User user = new User();
+        user.setEmail(email);
+        user.setPassword(password);
+        return userService.add(user);
+    }
+}

src/main/java/mate/academy/service/UserService.java

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+package mate.academy.service;
+
+import mate.academy.model.User;
+import java.util.Optional;
+
+public interface UserService {
+    User add(User user);
+
+    Optional<User> findByEmail(String email);
+}

src/main/java/mate/academy/service/impl/UserServiceImpl.java

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+package mate.academy.service.impl;
+
+import mate.academy.dao.UserDao;
+import mate.academy.lib.Inject;
+import java.util.Optional;
+import mate.academy.model.User;
+import mate.academy.service.UserService;
+import mate.academy.util.HashUtil;
+
+public class UserServiceImpl implements UserService {
+    @Inject
+    private UserDao userDao;
+
+    @Override
+    public User add(User user) {
+        user.setSalt(HashUtil.salt());
+        user.setPassword(HashUtil.hashPassword(user.getPassword(), user.getSalt()));
+        return userDao.save(user);
+    }
+
+    @Override
+    public Optional<User> findByEmail(String email) {
+        return userDao.findByEmail(email);
+    }
+}

src/main/java/mate/academy/util/HashUtil.java

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+package mate.academy.util;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+
+public class HashUtil {
+    private HashUtil() {
+    }
+
+    private static final String ALGORITHM = "SHA-256";
+
+    public static byte[] salt() {
+        SecureRandom secureRandom = new SecureRandom();
+        byte[] salt = new byte[16];
+        secureRandom.nextBytes(salt);
+        return salt;
+    }
+
+    public static String hashPassword(String password, byte[] salt) {
+        StringBuilder stringBuilder = new StringBuilder();
+        try {
+            MessageDigest messageDigest = MessageDigest.getInstance(ALGORITHM);
+            messageDigest.update(salt);
+            byte[] digest = messageDigest.digest(password.getBytes());
+            for (byte b : digest) {
+                stringBuilder.append(String.format("%02x",b));
+            }
+            return stringBuilder.toString();
+        } catch (NoSuchAlgorithmException e) {
+            throw new RuntimeException(e);
+        }
+    }
+}

src/main/resources/hibernate.cfg.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE hibernate-configuration PUBLIC
+        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
+        "http://hibernate.org/dtd/hibernate-configuration-3.0.dtd">
+
+<hibernate-configuration>
+    <session-factory>
+        <property name="hibernate.dialect">org.hibernate.dialect.MySQL8Dialect</property>
+        <property name="connection.url">jdbc:mysql://localhost:3306/ticket_app</property>
+        <property name="connection.driver_class">com.mysql.cj.jdbc.Driver</property>
+        <property name="connection.username">root</property>
+        <property name="connection.password">yourpassword</property>
+        <property name="show_sql">true</property>
+        <property name="hbm2ddl.auto">update</property>
+
+        <mapping class="mate.academy.model.CinemaHall"/>
+        <mapping class="mate.academy.model.Movie"/>
+        <mapping class="mate.academy.model.MovieSession"/>
+        <mapping class="mate.academy.model.User"/>
+    </session-factory>
+</hibernate-configuration>