🎉

.gitignore

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+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**/target/
+!**/src/test/**/target/
+
+### IntelliJ IDEA ###
+.idea/modules.xml
+.idea/jarRepositories.xml
+.idea/compiler.xml
+.idea/libraries/
+*.iws
+*.iml
+*.ipr
+
+### Eclipse ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### VS Code ###
+.vscode/
+
+### Mac OS ###
+.DS_Store

pom.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>fr.iut_fbleau.but3.dev62</groupId>
+  <artifactId>mylibrary</artifactId>
+  <version>1.0-SNAPSHOT</version>
+
+  <properties>
+    <!--    Your java version-->
+    <maven.compiler.source>21</maven.compiler.source>
+    <maven.compiler.target>21</maven.compiler.target>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+
+    <!--    Main dependencies -->
+    <lombok.version>1.18.36</lombok.version>
+
+    <!--    Test Verisons-->
+    <junit.version>5.11.4</junit.version>
+    <junit.platform.version>1.11.4</junit.platform.version>
+    <cucumber.version>7.21.1</cucumber.version>
+    <mockito.version>5.16.0</mockito.version>
+
+    <!--  Maven build version  -->
+    <maven.compiler.version>3.13.0</maven.compiler.version>
+    <maven.surefire.version>3.5.2</maven.surefire.version>
+  </properties>
+
+  <dependencyManagement>
+    <dependencies>
+      <dependency>
+        <groupId>io.cucumber</groupId>
+        <artifactId>cucumber-bom</artifactId>
+        <version>${cucumber.version}</version>
+        <type>pom</type>
+        <scope>import</scope>
+      </dependency>
+      <dependency>
+        <groupId>org.junit</groupId>
+        <artifactId>junit-bom</artifactId>
+        <version>${junit.version}</version>
+        <type>pom</type>
+        <scope>import</scope>
+      </dependency>
+    </dependencies>
+  </dependencyManagement>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.projectlombok</groupId>
+      <artifactId>lombok</artifactId>
+      <version>${lombok.version}</version>
+      <scope>provided</scope>
+    </dependency>
+
+    <dependency>
+      <groupId>io.cucumber</groupId>
+      <artifactId>cucumber-java</artifactId>
+      <scope>test</scope>
+    </dependency>
+
+    <dependency>
+      <groupId>io.cucumber</groupId>
+      <artifactId>cucumber-junit-platform-engine</artifactId>
+      <scope>test</scope>
+    </dependency>
+
+    <dependency>
+      <groupId>org.junit.platform</groupId>
+      <artifactId>junit-platform-suite</artifactId>
+      <version>${junit.platform.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.platform</groupId>
+      <artifactId>junit-platform-engine</artifactId>
+      <version>${junit.platform.version}</version>
+      <scope>test</scope>
+    </dependency>
+
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-api</artifactId>
+      <version>${junit.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-params</artifactId>
+      <version>${junit.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-engine</artifactId>
+      <version>${junit.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.platform</groupId>
+      <artifactId>junit-platform-launcher</artifactId>
+      <version>${junit.platform.version}</version>
+      <scope>test</scope>
+    </dependency>
+
+    <dependency>
+      <groupId>org.mockito</groupId>
+      <artifactId>mockito-core</artifactId>
+      <version>${mockito.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.mockito</groupId>
+      <artifactId>mockito-junit-jupiter</artifactId>
+      <version>${mockito.version}</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>${maven.compiler.version}</version>
+        <configuration>
+          <encoding>${project.build.sourceEncoding}</encoding>
+          <source>${maven.compiler.source}</source>
+          <target>${maven.compiler.target}</target>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <version>${maven.surefire.version}</version>
+        <configuration>
+          <properties>
+            <!-- Work around. Surefire does not include enough
+                 information to disambiguate between different
+                 examples and scenarios. -->
+            <configurationParameters>
+              cucumber.junit-platform.naming-strategy=long
+            </configurationParameters>
+          </properties>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+</project>

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/CustomerDTO.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.customer;
+
+import java.util.UUID;
+import lombok.Builder;
+import lombok.Getter;
+
+@Builder
+@Getter
+public class CustomerDTO {
+  private final UUID id;
+  private final String firstName;
+  private final String lastName;
+  private final String phoneNumber;
+  private final int loyaltyPoints;
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/CustomerInfo.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.customer;
+
+public record CustomerInfo(String firstName, String lastName, String phoneNumber) {
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/converter/CustomerConverter.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.customer.converter;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.entity.Customer;
+
+public final class CustomerConverter {
+  private CustomerConverter(){
+
+  }
+
+  public static Customer toDomain(CustomerInfo newCustomer) {
+    return Customer.builder()
+        .firstName(newCustomer.firstName())
+        .lastName(newCustomer.lastName())
+        .phoneNumber(newCustomer.phoneNumber())
+        .loyaltyPoints(0)
+        .build();
+  }
+
+  public static CustomerDTO toDTO(Customer customer) {
+    return CustomerDTO.builder()
+        .id(customer.getId())
+        .firstName(customer.getFirstName())
+        .lastName(customer.getLastName())
+        .phoneNumber(customer.getPhoneNumber())
+        .loyaltyPoints(customer.getLoyaltyPoints())
+        .build();
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/entity/Customer.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.customer.entity;
+
+
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.IllegalCustomerPointException;
+import java.util.UUID;
+import lombok.Builder;
+import lombok.Getter;
+
+@Builder
+@Getter
+public class Customer {
+ private UUID id;
+ private String firstName;
+ private String lastName;
+ private String phoneNumber;
+ private int loyaltyPoints;
+
+ public void setRandomUUID() {
+  this.id = UUID.randomUUID();
+ }
+
+ public void addLoyaltyPoints(int loyaltyPointToAdd) {
+  this.loyaltyPoints += loyaltyPointToAdd;
+ }
+
+ public void removeLoyaltyPoints(int loyaltyPointToRemove) throws IllegalCustomerPointException {
+  if (loyaltyPointToRemove > this.loyaltyPoints) throw new IllegalCustomerPointException(loyaltyPointToRemove, this.loyaltyPoints);
+  this.loyaltyPoints -= loyaltyPointToRemove;
+ }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/exception/CustomerNotFoundException.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.customer.exception;
+
+import java.text.MessageFormat;
+import java.util.UUID;
+
+public class CustomerNotFoundException extends Exception {
+
+  public static final String THE_CUSTOMER_WITH_ID_DOES_NOT_EXIST_MESSAGE = "The customer with id {0} does not exist";
+
+  public CustomerNotFoundException(UUID uuid) {
+    super(MessageFormat.format(THE_CUSTOMER_WITH_ID_DOES_NOT_EXIST_MESSAGE, uuid));
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/exception/IllegalCustomerPointException.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.customer.exception;
+
+import java.text.MessageFormat;
+
+public class IllegalCustomerPointException extends Exception {
+
+  public static final String CANNOT_REMOVE_LOYALTY_POINTS = "Cannot remove {0} points from {1} points";
+
+  public IllegalCustomerPointException(int needed, int actual) {
+    super(MessageFormat.format(CANNOT_REMOVE_LOYALTY_POINTS, needed,
+        actual));
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/exception/NotValidCustomerException.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.customer.exception;
+
+public class NotValidCustomerException extends Exception {
+
+  public NotValidCustomerException(String message) {
+    super(message);
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/repository/CustomerRepository.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.customer.repository;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.entity.Customer;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
+import lombok.NoArgsConstructor;
+
+@NoArgsConstructor
+public final class CustomerRepository {
+  private final List<Customer> customers = new ArrayList<>();
+
+  public List<Customer> findAll() {
+    return customers;
+  }
+
+  public void deleteAll() {
+    customers.clear();
+  }
+
+  public Customer save(Customer newCustomer) {
+    Optional<Customer> optionalCustomerWithSameId = this.findById(newCustomer.getId());
+    optionalCustomerWithSameId.ifPresentOrElse(customers::remove, newCustomer::setRandomUUID);
+    this.customers.add(newCustomer);
+    return newCustomer;
+  }
+
+  public Optional<Customer> findById(UUID uuid) {
+    return this.customers.stream()
+        .filter(customer -> customer.getId().equals(uuid))
+        .findFirst();
+  }
+
+  public boolean existsById(UUID uuid) {
+    return this.customers.stream()
+        .anyMatch(customer -> customer.getId().equals(uuid));
+  }
+
+  public Optional<Customer> findByPhoneNumber(String phoneNumber) {
+    return this.customers.stream()
+        .filter(customer -> customer.getPhoneNumber().equals(phoneNumber))
+        .findFirst();
+  }
+
+  public void delete(Customer customer) {
+    this.customers.remove(customer);
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/usecase/CustomerUseCase.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.customer.usecase;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.converter.CustomerConverter;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.entity.Customer;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.CustomerNotFoundException;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.IllegalCustomerPointException;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.NotValidCustomerException;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.repository.CustomerRepository;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.validator.CustomerValidator;
+import java.util.Optional;
+import java.util.UUID;
+
+public final class CustomerUseCase {
+
+  private final CustomerRepository customerRepository;
+
+  public CustomerUseCase(CustomerRepository customerRepository) {
+    this.customerRepository = customerRepository;
+  }
+
+  public UUID registerCustomer(CustomerInfo newCustomer) throws NotValidCustomerException {
+    CustomerValidator.validate(newCustomer);
+    Customer customerToRegister = CustomerConverter.toDomain(newCustomer);
+    Customer customerToRegistered = customerRepository.save(customerToRegister);
+    return customerToRegistered.getId();
+  }
+
+  public Optional<CustomerDTO> findCustomerByPhoneNumber(String phoneNumber) {
+    Optional<Customer> optionalCustomer = customerRepository.findByPhoneNumber(phoneNumber);
+    return optionalCustomer.map(CustomerConverter::toDTO);
+  }
+
+  public CustomerDTO updateCustomer(UUID uuid, CustomerInfo customerInfo)
+      throws CustomerNotFoundException, NotValidCustomerException {
+    CustomerValidator.validate(customerInfo);
+    Customer customerByUUID = getCustomerIfDoesNotExistThrowCustomerNotFoundException(
+        uuid);
+    Customer customer = Customer.builder()
+        .id(uuid)
+        .firstName(customerInfo.firstName())
+        .lastName(customerInfo.lastName())
+        .phoneNumber(customerInfo.phoneNumber())
+        .loyaltyPoints(customerByUUID.getLoyaltyPoints())
+        .build();
+    Customer updatedCustomer = customerRepository.save(customer);
+    return CustomerConverter.toDTO(updatedCustomer);
+  }
+
+  public void deleteCustomer(UUID uuid) throws CustomerNotFoundException {
+    Customer customerToDelete = getCustomerIfDoesNotExistThrowCustomerNotFoundException(uuid);
+    this.customerRepository.delete(customerToDelete);
+  }
+
+  public int addLoyaltyPoints(UUID uuid, int loyaltyPointToAdd) throws CustomerNotFoundException {
+    Customer customerToAddLoyaltyPoints = getCustomerIfDoesNotExistThrowCustomerNotFoundException(
+        uuid);
+    customerToAddLoyaltyPoints.addLoyaltyPoints(loyaltyPointToAdd);
+    customerRepository.save(customerToAddLoyaltyPoints);
+    return customerToAddLoyaltyPoints.getLoyaltyPoints();
+  }
+
+  public int subtractLoyaltyPoints(UUID uuid, int loyaltyPointToRemove)
+      throws CustomerNotFoundException, IllegalCustomerPointException {
+    Customer customerToSubtractLoyaltyPoints = getCustomerIfDoesNotExistThrowCustomerNotFoundException(
+        uuid);
+    customerToSubtractLoyaltyPoints.removeLoyaltyPoints(loyaltyPointToRemove);
+    customerRepository.save(customerToSubtractLoyaltyPoints);
+    return customerToSubtractLoyaltyPoints.getLoyaltyPoints();
+  }
+
+  private Customer getCustomerIfDoesNotExistThrowCustomerNotFoundException(UUID uuid)
+      throws CustomerNotFoundException {
+    Optional<Customer> optionalCustomerById = customerRepository.findById(uuid);
+    if (optionalCustomerById.isEmpty()) {
+      throw new CustomerNotFoundException(uuid);
+    }
+    return optionalCustomerById.get();
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/validator/CustomerValidator.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.customer.validator;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.NotValidCustomerException;
+
+public final class CustomerValidator {
+
+  public static final String PHONE_NUMBER_IS_NOT_VALID = "Phone number is not valid";
+  public static final String LAST_NAME_CANNOT_BE_BLANK = "Last name cannot be blank";
+  public static final String FIRST_NAME_CANNOT_BE_BLANK = "First name cannot be blank";
+  public static final String PHONE_NUMBER_REGEX = "0([67])\\d{8}";
+
+  private CustomerValidator() {
+
+  }
+
+  public static void validate(CustomerInfo newCustomer) throws NotValidCustomerException {
+    validateFirstName(newCustomer);
+    validateLastName(newCustomer);
+    validatePhoneNumber(newCustomer);
+  }
+
+  private static void validatePhoneNumber(CustomerInfo newCustomer)
+      throws NotValidCustomerException {
+    if (newCustomer.phoneNumber().isBlank()) {
+      throw new NotValidCustomerException("Phone number cannot be blank");
+    }
+    if (!newCustomer.phoneNumber().matches(PHONE_NUMBER_REGEX)) {
+      throw new NotValidCustomerException(PHONE_NUMBER_IS_NOT_VALID);
+    }
+  }
+
+  private static void validateLastName(CustomerInfo newCustomer) throws NotValidCustomerException {
+    if (newCustomer.lastName().isBlank()) {
+      throw new NotValidCustomerException(LAST_NAME_CANNOT_BE_BLANK);
+    }
+  }
+
+  private static void validateFirstName(CustomerInfo newCustomer) throws NotValidCustomerException {
+    if (newCustomer.firstName().isBlank()) {
+      throw new NotValidCustomerException(FIRST_NAME_CANNOT_BE_BLANK);
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/converter/CustomerConverterTest.java

@@ -0,0 +1,97 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.customer.converter;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.entity.Customer;
+import java.util.UUID;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
+@DisplayName("CustomerConverter Unit Tests")
+class CustomerConverterTest {
+
+  @Nested
+  @DisplayName("toDomain() method tests")
+  class ToDomainTests {
+
+    @Test
+    @DisplayName("Should convert CustomerInfo to Customer domain object with loyalty points initialized to 0")
+    void shouldConvertCustomerInfoToDomain() {
+      // Given
+      CustomerInfo customerInfo = new CustomerInfo("John", "Doe", "0123456789");
+
+      // When
+      Customer result = CustomerConverter.toDomain(customerInfo);
+
+      // Then
+      assertNotNull(result);
+      assertEquals(customerInfo.firstName(), result.getFirstName());
+      assertEquals(customerInfo.lastName(), result.getLastName());
+      assertEquals(customerInfo.phoneNumber(), result.getPhoneNumber());
+      assertEquals(0, result.getLoyaltyPoints());
+    }
+  }
+
+  @Nested
+  @DisplayName("toDTO() method tests")
+  class ToDTOTests {
+
+    @Test
+    @DisplayName("Should convert Customer domain object to CustomerDTO with all fields mapped correctly")
+    void shouldConvertCustomerToDTO() {
+      Customer customer = Customer.builder()
+          .id(UUID.randomUUID())
+          .firstName("Jane")
+          .lastName("Smith")
+          .phoneNumber("9876543210")
+          .loyaltyPoints(100)
+          .build();
+
+      CustomerDTO result = CustomerConverter.toDTO(customer);
+
+      assertNotNull(result);
+      assertEquals(customer.getId(), result.getId());
+      assertEquals(customer.getFirstName(), result.getFirstName());
+      assertEquals(customer.getLastName(), result.getLastName());
+      assertEquals(customer.getPhoneNumber(), result.getPhoneNumber());
+      assertEquals(customer.getLoyaltyPoints(), result.getLoyaltyPoints());
+    }
+  }
+
+  @Test
+  @DisplayName("Should handle null values properly when converting between objects")
+  void shouldHandleNullValuesGracefully() {
+    Customer customer = Customer.builder()
+        .id(UUID.randomUUID())
+        .firstName(null)
+        .lastName("NullTest")
+        .phoneNumber(null)
+        .loyaltyPoints(50)
+        .build();
+
+    CustomerDTO result = CustomerConverter.toDTO(customer);
+
+    assertNotNull(result);
+    assertNull(result.getFirstName());
+    assertEquals("NullTest", result.getLastName());
+    assertNull(result.getPhoneNumber());
+  }
+
+  @Test
+  @DisplayName("Should preserve empty string values during conversion")
+  void shouldPreserveEmptyStrings() {
+    CustomerInfo customerInfo = new CustomerInfo("", "", "");
+
+    Customer domainResult = CustomerConverter.toDomain(customerInfo);
+    CustomerDTO dtoResult = CustomerConverter.toDTO(domainResult);
+
+    assertEquals("", dtoResult.getFirstName());
+    assertEquals("", dtoResult.getLastName());
+    assertEquals("", dtoResult.getPhoneNumber());
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/entity/CustomerTest.java

@@ -0,0 +1,136 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.customer.entity;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.IllegalCustomerPointException;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.util.UUID;
+
+class CustomerTest {
+
+  @Test
+  @DisplayName("Builder should create a valid Customer instance")
+  void testCustomerBuilder() {
+    UUID id = UUID.randomUUID();
+    String firstName = "John";
+    String lastName = "Doe";
+    String phoneNumber = "0123456789";
+    int loyaltyPoints = 100;
+
+    Customer customer = Customer.builder()
+        .id(id)
+        .firstName(firstName)
+        .lastName(lastName)
+        .phoneNumber(phoneNumber)
+        .loyaltyPoints(loyaltyPoints)
+        .build();
+
+    assertEquals(id, customer.getId());
+    assertEquals(firstName, customer.getFirstName());
+    assertEquals(lastName, customer.getLastName());
+    assertEquals(phoneNumber, customer.getPhoneNumber());
+    assertEquals(loyaltyPoints, customer.getLoyaltyPoints());
+  }
+
+  @Test
+  @DisplayName("setRandomUUID should change the ID to a new random UUID")
+  void testSetRandomUUID() {
+    Customer customer = Customer.builder().build();
+    UUID originalId = customer.getId();
+
+    customer.setRandomUUID();
+
+    assertNotNull(customer.getId());
+    assertNotEquals(originalId, customer.getId());
+  }
+
+  @Nested
+  @DisplayName("Loyalty Points Tests")
+  class LoyaltyPointsTests {
+
+    @Test
+    @DisplayName("addLoyaltyPoints should correctly increment loyalty points")
+    void testAddLoyaltyPoints() {
+      Customer customer = Customer.builder()
+          .loyaltyPoints(50)
+          .build();
+      int pointsToAdd = 25;
+      int expectedPoints = 75;
+
+      customer.addLoyaltyPoints(pointsToAdd);
+
+      assertEquals(expectedPoints, customer.getLoyaltyPoints());
+    }
+
+    @Test
+    @DisplayName("addLoyaltyPoints should handle zero points correctly")
+    void testAddZeroLoyaltyPoints() {
+      Customer customer = Customer.builder()
+          .loyaltyPoints(50)
+          .build();
+
+      customer.addLoyaltyPoints(0);
+
+      assertEquals(50, customer.getLoyaltyPoints());
+    }
+
+    @Test
+    @DisplayName("removeLoyaltyPoints should correctly decrement loyalty points")
+    void testRemoveLoyaltyPoints() throws IllegalCustomerPointException {
+      Customer customer = Customer.builder()
+          .loyaltyPoints(50)
+          .build();
+      int pointsToRemove = 20;
+      int expectedPoints = 30;
+
+      customer.removeLoyaltyPoints(pointsToRemove);
+
+      assertEquals(expectedPoints, customer.getLoyaltyPoints());
+    }
+
+    @Test
+    @DisplayName("removeLoyaltyPoints should handle removing exactly all points")
+    void testRemoveAllLoyaltyPoints() throws IllegalCustomerPointException {
+      Customer customer = Customer.builder()
+          .loyaltyPoints(50)
+          .build();
+
+      customer.removeLoyaltyPoints(50);
+
+      assertEquals(0, customer.getLoyaltyPoints());
+    }
+
+    @Test
+    @DisplayName("removeLoyaltyPoints should throw exception when trying to remove more points than available")
+    void testRemoveTooManyLoyaltyPoints() {
+      Customer customer = Customer.builder()
+          .loyaltyPoints(50)
+          .build();
+      int pointsToRemove = 75;
+
+      IllegalCustomerPointException exception = assertThrows(
+          IllegalCustomerPointException.class,
+          () -> customer.removeLoyaltyPoints(pointsToRemove)
+      );
+
+      assertEquals(50, customer.getLoyaltyPoints());
+
+      assertTrue(exception.getMessage().contains(String.valueOf(pointsToRemove)));
+      assertTrue(exception.getMessage().contains(String.valueOf(customer.getLoyaltyPoints())));
+    }
+
+    @Test
+    @DisplayName("removeLoyaltyPoints should handle removing zero points correctly")
+    void testRemoveZeroLoyaltyPoints() throws IllegalCustomerPointException {
+      Customer customer = Customer.builder()
+          .loyaltyPoints(50)
+          .build();
+
+      customer.removeLoyaltyPoints(0);
+
+      assertEquals(50, customer.getLoyaltyPoints());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/exception/CustomerNotFoundExceptionTest.java

@@ -0,0 +1,49 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.customer.exception;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class CustomerNotFoundExceptionTest {
+
+  @Test
+  @DisplayName("Exception message should contain the UUID provided")
+  void testExceptionMessageContainsUUID() {
+    UUID uuid = UUID.randomUUID();
+
+    CustomerNotFoundException exception = new CustomerNotFoundException(uuid);
+
+    String expectedMessage = String.format("The customer with id %s does not exist", uuid);
+    assertEquals(expectedMessage, exception.getMessage());
+  }
+
+  @Test
+  @DisplayName("Exception should use the correct constant message format")
+  void testExceptionUsesConstantMessageFormat() {
+    UUID uuid = UUID.randomUUID();
+
+    CustomerNotFoundException exception = new CustomerNotFoundException(uuid);
+
+    String expectedFormatWithPlaceholder = "The customer with id {0} does not exist";
+    assertEquals(CustomerNotFoundException.THE_CUSTOMER_WITH_ID_DOES_NOT_EXIST_MESSAGE,
+        expectedFormatWithPlaceholder);
+    assertTrue(exception.getMessage().contains(uuid.toString()));
+  }
+
+  @Test
+  @DisplayName("Exception should be properly thrown and caught")
+  void testExceptionCanBeThrownAndCaught() {
+    UUID uuid = UUID.randomUUID();
+
+    try {
+      throw new CustomerNotFoundException(uuid);
+    } catch (CustomerNotFoundException e) {
+      String expectedMessage = String.format("The customer with id %s does not exist", uuid);
+      assertEquals(expectedMessage, e.getMessage());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/exception/IllegalCustomerPointExceptionTest.java

@@ -0,0 +1,69 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.customer.exception;
+
+import java.text.MessageFormat;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class IllegalCustomerPointExceptionTest {
+
+  @Test
+  @DisplayName("Exception message should contain the needed and actual points")
+  void testExceptionMessageContainsPoints() {
+    int neededPoints = 100;
+    int actualPoints = 50;
+
+    IllegalCustomerPointException exception = new IllegalCustomerPointException(neededPoints, actualPoints);
+
+    String expectedMessage = "Cannot remove 100 points from 50 points";
+    assertEquals(expectedMessage, exception.getMessage());
+  }
+
+  @ParameterizedTest
+  @CsvSource({
+      "100, 50",
+      "75, 25",
+      "200, 150",
+      "1000, 750"
+  })
+  @DisplayName("Exception message should be formatted correctly for different point values")
+  void testExceptionMessageForDifferentPointValues(int neededPoints, int actualPoints) {
+    IllegalCustomerPointException exception = new IllegalCustomerPointException(neededPoints, actualPoints);
+
+    String expectedMessage = MessageFormat.format(IllegalCustomerPointException.CANNOT_REMOVE_LOYALTY_POINTS, neededPoints, actualPoints);
+    assertEquals(expectedMessage, exception.getMessage());
+  }
+
+  @Test
+  @DisplayName("Exception should use the correct constant message format")
+  void testExceptionUsesConstantMessageFormat() {
+    int neededPoints = 100;
+    int actualPoints = 50;
+
+    IllegalCustomerPointException exception = new IllegalCustomerPointException(neededPoints, actualPoints);
+
+    String expectedFormatWithPlaceholder = "Cannot remove {0} points from {1} points";
+    assertEquals(IllegalCustomerPointException.CANNOT_REMOVE_LOYALTY_POINTS,
+        expectedFormatWithPlaceholder);
+    assertTrue(exception.getMessage().contains(String.valueOf(neededPoints)));
+    assertTrue(exception.getMessage().contains(String.valueOf(actualPoints)));
+  }
+
+  @Test
+  @DisplayName("Exception should be properly thrown and caught")
+  void testExceptionCanBeThrownAndCaught() {
+    int neededPoints = 100;
+    int actualPoints = 50;
+
+    try {
+      throw new IllegalCustomerPointException(neededPoints, actualPoints);
+    } catch (IllegalCustomerPointException e) {
+      String expectedMessage = String.format("Cannot remove %d points from %d points", neededPoints, actualPoints);
+      assertEquals(expectedMessage, e.getMessage());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/exception/NotValidCustomerExceptionTest.java

@@ -0,0 +1,61 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.customer.exception;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class NotValidCustomerExceptionTest {
+
+  @Test
+  @DisplayName("Exception should be created with the provided message")
+  void testExceptionCreation() {
+    String errorMessage = "Customer data is not valid";
+
+    NotValidCustomerException exception = new NotValidCustomerException(errorMessage);
+
+    assertEquals(errorMessage, exception.getMessage());
+  }
+
+  @ParameterizedTest
+  @ValueSource(strings = {
+      "First name is required",
+      "Last name cannot be empty",
+      "Phone number format is invalid",
+      "Customer age must be above 18"
+  })
+  @DisplayName("Exception should handle different validation messages")
+  void testExceptionWithDifferentMessages(String errorMessage) {
+    NotValidCustomerException exception = new NotValidCustomerException(errorMessage);
+
+    assertEquals(errorMessage, exception.getMessage());
+  }
+
+  @Test
+  @DisplayName("Exception should be properly thrown and caught")
+  void testExceptionCanBeThrownAndCaught() {
+    String errorMessage = "Required field is missing";
+
+    Exception exception = assertThrows(NotValidCustomerException.class, () -> {
+      throw new NotValidCustomerException(errorMessage);
+    });
+
+    assertEquals(errorMessage, exception.getMessage());
+  }
+
+  @Test
+  @DisplayName("Exception should be catchable as a general Exception")
+  void testExceptionInheritance() {
+    String errorMessage = "Invalid customer data";
+
+    try {
+      throw new NotValidCustomerException(errorMessage);
+    } catch (Exception e) {
+      assertEquals(NotValidCustomerException.class, e.getClass());
+      assertEquals(errorMessage, e.getMessage());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/repository/CustomerRepositoryTest.java

@@ -0,0 +1,227 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.customer.repository;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.entity.Customer;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class CustomerRepositoryTest {
+
+  private CustomerRepository repository;
+  private Customer customer1;
+  private Customer customer2;
+
+  @BeforeEach
+  void setUp() {
+    repository = new CustomerRepository();
+
+    customer1 = Customer.builder()
+        .firstName("John")
+        .lastName("Doe")
+        .phoneNumber("0123456789")
+        .loyaltyPoints(100)
+        .build();
+    customer1.setRandomUUID();
+
+    customer2 = Customer.builder()
+        .firstName("Jane")
+        .lastName("Smith")
+        .phoneNumber("9876543210")
+        .loyaltyPoints(200)
+        .build();
+    customer2.setRandomUUID();
+  }
+
+  @Test
+  @DisplayName("New repository should be empty")
+  void testNewRepositoryIsEmpty() {
+    List<Customer> customers = repository.findAll();
+
+    assertTrue(customers.isEmpty());
+    assertEquals(0, customers.size());
+  }
+
+  @Nested
+  @DisplayName("Save operations")
+  class SaveOperations {
+
+    @Test
+    @DisplayName("Save should add a new customer")
+    void testSaveNewCustomer() {
+      Customer savedCustomer = repository.save(customer1);
+
+      assertEquals(1, repository.findAll().size());
+      assertEquals(customer1.getId(), savedCustomer.getId());
+      assertEquals(customer1.getFirstName(), savedCustomer.getFirstName());
+    }
+
+    @Test
+    @DisplayName("Save should update existing customer with same ID")
+    void testSaveUpdatesExistingCustomer() {
+      repository.save(customer1);
+
+      UUID id = customer1.getId();
+      Customer updatedCustomer = Customer.builder()
+          .id(id)
+          .firstName("John")
+          .lastName("Updated")
+          .phoneNumber("1111111111")
+          .loyaltyPoints(150)
+          .build();
+
+      Customer savedCustomer = repository.save(updatedCustomer);
+
+      assertEquals(1, repository.findAll().size());
+      assertEquals(id, savedCustomer.getId());
+      assertEquals("Updated", savedCustomer.getLastName());
+      assertEquals("1111111111", savedCustomer.getPhoneNumber());
+      assertEquals(150, savedCustomer.getLoyaltyPoints());
+    }
+
+    @Test
+    @DisplayName("Save multiple customers should add all of them")
+    void testSaveMultipleCustomers() {
+      repository.save(customer1);
+      repository.save(customer2);
+
+      List<Customer> customers = repository.findAll();
+
+      assertEquals(2, customers.size());
+      assertTrue(customers.contains(customer1));
+      assertTrue(customers.contains(customer2));
+    }
+  }
+
+  @Nested
+  @DisplayName("Find operations")
+  class FindOperations {
+
+    @BeforeEach
+    void setUpCustomers() {
+      repository.save(customer1);
+      repository.save(customer2);
+    }
+
+    @Test
+    @DisplayName("FindAll should return all customers")
+    void testFindAll() {
+      List<Customer> customers = repository.findAll();
+
+      assertEquals(2, customers.size());
+      assertTrue(customers.contains(customer1));
+      assertTrue(customers.contains(customer2));
+    }
+
+    @Test
+    @DisplayName("FindById should return customer with matching ID")
+    void testFindById() {
+      Optional<Customer> foundCustomer = repository.findById(customer1.getId());
+
+      assertTrue(foundCustomer.isPresent());
+      assertEquals(customer1.getFirstName(), foundCustomer.get().getFirstName());
+      assertEquals(customer1.getLastName(), foundCustomer.get().getLastName());
+    }
+
+    @Test
+    @DisplayName("FindById should return empty Optional when ID doesn't exist")
+    void testFindByIdNotFound() {
+      UUID nonExistentId = UUID.randomUUID();
+
+      Optional<Customer> foundCustomer = repository.findById(nonExistentId);
+
+      assertTrue(foundCustomer.isEmpty());
+    }
+
+    @Test
+    @DisplayName("FindByPhoneNumber should return customer with matching phone number")
+    void testFindByPhoneNumber() {
+      Optional<Customer> foundCustomer = repository.findByPhoneNumber("0123456789");
+
+      assertTrue(foundCustomer.isPresent());
+      assertEquals(customer1.getId(), foundCustomer.get().getId());
+      assertEquals(customer1.getFirstName(), foundCustomer.get().getFirstName());
+    }
+
+    @Test
+    @DisplayName("FindByPhoneNumber should return empty Optional when phone number doesn't exist")
+    void testFindByPhoneNumberNotFound() {
+      Optional<Customer> foundCustomer = repository.findByPhoneNumber("0000000000");
+
+      assertTrue(foundCustomer.isEmpty());
+    }
+
+    @Test
+    @DisplayName("ExistsById should return true when ID exists")
+    void testExistsByIdExists() {
+      boolean exists = repository.existsById(customer1.getId());
+
+      assertTrue(exists);
+    }
+
+    @Test
+    @DisplayName("ExistsById should return false when ID doesn't exist")
+    void testExistsByIdNotExists() {
+      UUID nonExistentId = UUID.randomUUID();
+
+      boolean exists = repository.existsById(nonExistentId);
+
+      assertFalse(exists);
+    }
+  }
+
+  @Nested
+  @DisplayName("Delete operations")
+  class DeleteOperations {
+
+    @BeforeEach
+    void setUpCustomers() {
+      repository.save(customer1);
+      repository.save(customer2);
+    }
+
+    @Test
+    @DisplayName("Delete should remove the specified customer")
+    void testDelete() {
+      repository.delete(customer1);
+
+      List<Customer> customers = repository.findAll();
+
+      assertEquals(1, customers.size());
+      assertFalse(customers.contains(customer1));
+      assertTrue(customers.contains(customer2));
+    }
+
+    @Test
+    @DisplayName("DeleteAll should remove all customers")
+    void testDeleteAll() {
+      repository.deleteAll();
+
+      List<Customer> customers = repository.findAll();
+
+      assertTrue(customers.isEmpty());
+      assertEquals(0, customers.size());
+    }
+
+    @Test
+    @DisplayName("Delete should not throw exception when customer doesn't exist")
+    void testDeleteNonExistentCustomer() {
+      Customer nonExistentCustomer = Customer.builder()
+          .firstName("Non")
+          .lastName("Existent")
+          .phoneNumber("0000000000")
+          .build();
+      nonExistentCustomer.setRandomUUID();
+
+      assertDoesNotThrow(() -> repository.delete(nonExistentCustomer));
+
+      assertEquals(2, repository.findAll().size());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/usecase/CustomerUseCaseTest.java

@@ -0,0 +1,279 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.customer.usecase;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.entity.Customer;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.CustomerNotFoundException;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.IllegalCustomerPointException;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.NotValidCustomerException;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.repository.CustomerRepository;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import java.util.Optional;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.*;
+
+@ExtendWith(MockitoExtension.class)
+class CustomerUseCaseTest {
+
+  @Mock
+  private CustomerRepository customerRepository;
+
+  @InjectMocks
+  private CustomerUseCase customerUseCase;
+
+  private UUID customerId;
+  private Customer testCustomer;
+  private CustomerInfo validCustomerInfo;
+
+  @BeforeEach
+  void setUp() {
+    customerId = UUID.randomUUID();
+    testCustomer = Customer.builder()
+        .id(customerId)
+        .firstName("John")
+        .lastName("Doe")
+        .phoneNumber("0612345678")
+        .loyaltyPoints(100)
+        .build();
+
+    validCustomerInfo = new CustomerInfo("John", "Doe", "0612345678");
+  }
+
+  @Nested
+  @DisplayName("Register customer tests")
+  class RegisterCustomerTests {
+
+    @Test
+    @DisplayName("Should register customer when valid data is provided")
+    void testRegisterCustomerWithValidData() throws NotValidCustomerException {
+      when(customerRepository.save(any(Customer.class))).thenReturn(testCustomer);
+
+      UUID registeredId = customerUseCase.registerCustomer(validCustomerInfo);
+
+      assertNotNull(registeredId);
+      assertEquals(customerId, registeredId);
+      verify(customerRepository, times(1)).save(any(Customer.class));
+    }
+
+    @Test
+    @DisplayName("Should throw exception when customer data is not valid")
+    void testRegisterCustomerWithInvalidData() {
+      CustomerInfo invalidCustomerInfo = new CustomerInfo("", "", "");
+
+      assertThrows(NotValidCustomerException.class,
+          () -> customerUseCase.registerCustomer(invalidCustomerInfo));
+
+      verify(customerRepository, never()).save(any(Customer.class));
+    }
+  }
+
+  @Nested
+  @DisplayName("Find customer tests")
+  class FindCustomerTests {
+
+    @Test
+    @DisplayName("Should return customer when phone number exists")
+    void testFindCustomerByPhoneNumber() {
+      when(customerRepository.findByPhoneNumber("0612345678")).thenReturn(Optional.of(testCustomer));
+
+      Optional<CustomerDTO> foundCustomer = customerUseCase.findCustomerByPhoneNumber("0612345678");
+
+      assertTrue(foundCustomer.isPresent());
+      assertEquals(testCustomer.getId(), foundCustomer.get().getId());
+      assertEquals(testCustomer.getFirstName(), foundCustomer.get().getFirstName());
+      verify(customerRepository, times(1)).findByPhoneNumber("0612345678");
+    }
+
+    @Test
+    @DisplayName("Should return empty Optional when phone number doesn't exist")
+    void testFindCustomerByPhoneNumberNotFound() {
+      when(customerRepository.findByPhoneNumber("0799999999")).thenReturn(Optional.empty());
+
+      Optional<CustomerDTO> foundCustomer = customerUseCase.findCustomerByPhoneNumber("0799999999");
+
+      assertTrue(foundCustomer.isEmpty());
+      verify(customerRepository, times(1)).findByPhoneNumber("0799999999");
+    }
+  }
+
+  @Nested
+  @DisplayName("Update customer tests")
+  class UpdateCustomerTests {
+
+    @Test
+    @DisplayName("Should update customer when valid data is provided")
+    void testUpdateCustomerWithValidData() throws CustomerNotFoundException, NotValidCustomerException {
+      when(customerRepository.findById(customerId)).thenReturn(Optional.of(testCustomer));
+
+      Customer updatedCustomer = Customer.builder()
+          .id(customerId)
+          .firstName("John")
+          .lastName("Updated")
+          .phoneNumber("0712345678")
+          .loyaltyPoints(100)
+          .build();
+
+      when(customerRepository.save(any(Customer.class))).thenReturn(updatedCustomer);
+
+      CustomerInfo updateInfo = new CustomerInfo("John", "Updated", "0712345678");
+
+      CustomerDTO result = customerUseCase.updateCustomer(customerId, updateInfo);
+
+      assertNotNull(result);
+      assertEquals(customerId, result.getId());
+      assertEquals("Updated", result.getLastName());
+      assertEquals("0712345678", result.getPhoneNumber());
+      verify(customerRepository, times(1)).findById(customerId);
+      verify(customerRepository, times(1)).save(any(Customer.class));
+    }
+
+    @Test
+    @DisplayName("Should throw exception when customer ID doesn't exist")
+    void testUpdateCustomerNotFound() {
+      UUID nonExistentId = UUID.randomUUID();
+      when(customerRepository.findById(nonExistentId)).thenReturn(Optional.empty());
+
+      CustomerInfo updateInfo = new CustomerInfo("John", "Updated", "0712345678");
+
+      assertThrows(CustomerNotFoundException.class,
+          () -> customerUseCase.updateCustomer(nonExistentId, updateInfo));
+
+      verify(customerRepository, times(1)).findById(nonExistentId);
+      verify(customerRepository, never()).save(any(Customer.class));
+    }
+
+    @Test
+    @DisplayName("Should throw exception when update data is not valid")
+    void testUpdateCustomerWithInvalidData() {
+      CustomerInfo invalidUpdateInfo = new CustomerInfo("", "", "");
+
+      assertThrows(NotValidCustomerException.class,
+          () -> customerUseCase.updateCustomer(customerId, invalidUpdateInfo));
+
+      verify(customerRepository, never()).findById(any(UUID.class));
+      verify(customerRepository, never()).save(any(Customer.class));
+    }
+  }
+
+  @Nested
+  @DisplayName("Delete customer tests")
+  class DeleteCustomerTests {
+
+    @Test
+    @DisplayName("Should delete customer when ID exists")
+    void testDeleteCustomer() throws CustomerNotFoundException {
+      when(customerRepository.findById(customerId)).thenReturn(Optional.of(testCustomer));
+      doNothing().when(customerRepository).delete(testCustomer);
+
+      customerUseCase.deleteCustomer(customerId);
+
+      verify(customerRepository, times(1)).findById(customerId);
+      verify(customerRepository, times(1)).delete(testCustomer);
+    }
+
+    @Test
+    @DisplayName("Should throw exception when customer ID doesn't exist")
+    void testDeleteCustomerNotFound() {
+      UUID nonExistentId = UUID.randomUUID();
+      when(customerRepository.findById(nonExistentId)).thenReturn(Optional.empty());
+
+      assertThrows(CustomerNotFoundException.class,
+          () -> customerUseCase.deleteCustomer(nonExistentId));
+
+      verify(customerRepository, times(1)).findById(nonExistentId);
+      verify(customerRepository, never()).delete(any(Customer.class));
+    }
+  }
+
+  @Nested
+  @DisplayName("Loyalty points tests")
+  class LoyaltyPointsTests {
+
+    @Test
+    @DisplayName("Should add loyalty points to customer")
+    void testAddLoyaltyPoints() throws CustomerNotFoundException {
+      when(customerRepository.findById(customerId)).thenReturn(Optional.of(testCustomer));
+      when(customerRepository.save(testCustomer)).thenReturn(testCustomer);
+
+      int initialPoints = testCustomer.getLoyaltyPoints();
+      int pointsToAdd = 50;
+      int expectedPoints = initialPoints + pointsToAdd;
+
+      int newPoints = customerUseCase.addLoyaltyPoints(customerId, pointsToAdd);
+
+      assertEquals(expectedPoints, newPoints);
+      assertEquals(expectedPoints, testCustomer.getLoyaltyPoints());
+      verify(customerRepository, times(1)).findById(customerId);
+      verify(customerRepository, times(1)).save(testCustomer);
+    }
+
+    @Test
+    @DisplayName("Should throw exception when adding points to non-existent customer")
+    void testAddLoyaltyPointsToNonExistentCustomer() {
+      UUID nonExistentId = UUID.randomUUID();
+      when(customerRepository.findById(nonExistentId)).thenReturn(Optional.empty());
+
+      assertThrows(CustomerNotFoundException.class,
+          () -> customerUseCase.addLoyaltyPoints(nonExistentId, 50));
+
+      verify(customerRepository, times(1)).findById(nonExistentId);
+      verify(customerRepository, never()).save(any(Customer.class));
+    }
+
+    @Test
+    @DisplayName("Should subtract loyalty points from customer")
+    void testSubtractLoyaltyPoints() throws CustomerNotFoundException, IllegalCustomerPointException {
+      when(customerRepository.findById(customerId)).thenReturn(Optional.of(testCustomer));
+      when(customerRepository.save(testCustomer)).thenReturn(testCustomer);
+
+      int initialPoints = testCustomer.getLoyaltyPoints();
+      int pointsToRemove = 30;
+      int expectedPoints = initialPoints - pointsToRemove;
+
+      int newPoints = customerUseCase.subtractLoyaltyPoints(customerId, pointsToRemove);
+
+      assertEquals(expectedPoints, newPoints);
+      assertEquals(expectedPoints, testCustomer.getLoyaltyPoints());
+      verify(customerRepository, times(1)).findById(customerId);
+      verify(customerRepository, times(1)).save(testCustomer);
+    }
+
+    @Test
+    @DisplayName("Should throw exception when trying to remove more points than available")
+    void testSubtractTooManyLoyaltyPoints() {
+      when(customerRepository.findById(customerId)).thenReturn(Optional.of(testCustomer));
+
+      int pointsToRemove = 200;
+
+      assertThrows(IllegalCustomerPointException.class,
+          () -> customerUseCase.subtractLoyaltyPoints(customerId, pointsToRemove));
+
+      verify(customerRepository, times(1)).findById(customerId);
+      verify(customerRepository, never()).save(any(Customer.class));
+    }
+
+    @Test
+    @DisplayName("Should throw exception when subtracting points from non-existent customer")
+    void testSubtractLoyaltyPointsFromNonExistentCustomer() {
+      UUID nonExistentId = UUID.randomUUID();
+      when(customerRepository.findById(nonExistentId)).thenReturn(Optional.empty());
+
+      assertThrows(CustomerNotFoundException.class,
+          () -> customerUseCase.subtractLoyaltyPoints(nonExistentId, 50));
+
+      verify(customerRepository, times(1)).findById(nonExistentId);
+      verify(customerRepository, never()).save(any(Customer.class));
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/customer/validator/CustomerValidatorTest.java

@@ -0,0 +1,155 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.customer.validator;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.NotValidCustomerException;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class CustomerValidatorTest {
+
+  @Test
+  @DisplayName("Should validate customer with valid data")
+  void testValidateValidCustomer() {
+    CustomerInfo validCustomer = new CustomerInfo("John", "Doe", "0612345678");
+
+    assertDoesNotThrow(() -> CustomerValidator.validate(validCustomer));
+  }
+
+  @Nested
+  @DisplayName("First name validation tests")
+  class FirstNameValidationTests {
+
+    @Test
+    @DisplayName("Should throw exception when first name is blank")
+    void testValidateBlankFirstName() {
+      CustomerInfo customerWithBlankFirstName = new CustomerInfo("", "Doe", "0612345678");
+
+      NotValidCustomerException exception = assertThrows(
+          NotValidCustomerException.class,
+          () -> CustomerValidator.validate(customerWithBlankFirstName)
+      );
+
+      assertEquals(CustomerValidator.FIRST_NAME_CANNOT_BE_BLANK, exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ValueSource(strings = {" ", "  ", "\t", "\n"})
+    @DisplayName("Should throw exception when first name contains only whitespace")
+    void testValidateWhitespaceFirstName(String whitespace) {
+      CustomerInfo customerWithWhitespaceFirstName = new CustomerInfo(whitespace, "Doe", "0612345678");
+
+      NotValidCustomerException exception = assertThrows(
+          NotValidCustomerException.class,
+          () -> CustomerValidator.validate(customerWithWhitespaceFirstName)
+      );
+
+      assertEquals(CustomerValidator.FIRST_NAME_CANNOT_BE_BLANK, exception.getMessage());
+    }
+  }
+
+  @Nested
+  @DisplayName("Last name validation tests")
+  class LastNameValidationTests {
+
+    @Test
+    @DisplayName("Should throw exception when last name is blank")
+    void testValidateBlankLastName() {
+      CustomerInfo customerWithBlankLastName = new CustomerInfo("John", "", "0612345678");
+
+      NotValidCustomerException exception = assertThrows(
+          NotValidCustomerException.class,
+          () -> CustomerValidator.validate(customerWithBlankLastName)
+      );
+
+      assertEquals(CustomerValidator.LAST_NAME_CANNOT_BE_BLANK, exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ValueSource(strings = {" ", "  ", "\t", "\n"})
+    @DisplayName("Should throw exception when last name contains only whitespace")
+    void testValidateWhitespaceLastName(String whitespace) {
+      CustomerInfo customerWithWhitespaceLastName = new CustomerInfo("John", whitespace, "0612345678");
+
+      NotValidCustomerException exception = assertThrows(
+          NotValidCustomerException.class,
+          () -> CustomerValidator.validate(customerWithWhitespaceLastName)
+      );
+
+      assertEquals(CustomerValidator.LAST_NAME_CANNOT_BE_BLANK, exception.getMessage());
+    }
+  }
+
+  @Nested
+  @DisplayName("Phone number validation tests")
+  class PhoneNumberValidationTests {
+
+    @Test
+    @DisplayName("Should throw exception when phone number is blank")
+    void testValidateBlankPhoneNumber() {
+      CustomerInfo customerWithBlankPhoneNumber = new CustomerInfo("John", "Doe", "");
+
+      NotValidCustomerException exception = assertThrows(
+          NotValidCustomerException.class,
+          () -> CustomerValidator.validate(customerWithBlankPhoneNumber)
+      );
+
+      assertEquals("Phone number cannot be blank", exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ValueSource(strings = {" ", "  ", "\t", "\n"})
+    @DisplayName("Should throw exception when phone number contains only whitespace")
+    void testValidateWhitespacePhoneNumber(String whitespace) {
+      CustomerInfo customerWithWhitespacePhoneNumber = new CustomerInfo("John", "Doe", whitespace);
+
+      NotValidCustomerException exception = assertThrows(
+          NotValidCustomerException.class,
+          () -> CustomerValidator.validate(customerWithWhitespacePhoneNumber)
+      );
+
+      assertEquals("Phone number cannot be blank", exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ValueSource(strings = {
+        "0512345678", // Invalid prefix (not 06 or 07)
+        "0812345678", // Invalid prefix (not 06 or 07)
+        "061234567",  // Too short (missing one digit)
+        "06123456789", // Too long (one extra digit)
+        "6123456789", // Missing leading 0
+        "O612345678", // Letter O instead of zero
+        "+33612345678", // International format not supported
+        "06 12 34 56 78" // Contains spaces
+    })
+    @DisplayName("Should throw exception when phone number format is invalid")
+    void testValidateInvalidPhoneNumberFormat(String invalidPhoneNumber) {
+      CustomerInfo customerWithInvalidPhoneNumber = new CustomerInfo("John", "Doe", invalidPhoneNumber);
+
+      NotValidCustomerException exception = assertThrows(
+          NotValidCustomerException.class,
+          () -> CustomerValidator.validate(customerWithInvalidPhoneNumber)
+      );
+
+      assertEquals(CustomerValidator.PHONE_NUMBER_IS_NOT_VALID, exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ValueSource(strings = {
+        "0612345678", // Valid 06 number
+        "0712345678", // Valid 07 number
+        "0699999999", // Valid 06 number with all 9s
+        "0700000000"  // Valid 07 number with all 0s
+    })
+    @DisplayName("Should validate when phone number format is valid")
+    void testValidateValidPhoneNumberFormat(String validPhoneNumber) {
+      CustomerInfo customerWithValidPhoneNumber = new CustomerInfo("John", "Doe", validPhoneNumber);
+
+      assertDoesNotThrow(() -> CustomerValidator.validate(customerWithValidPhoneNumber));
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/features/RunCucumberTest.java

@@ -0,0 +1,14 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.features;
+
+import org.junit.platform.suite.api.*;
+
+import static io.cucumber.junit.platform.engine.Constants.GLUE_PROPERTY_NAME;
+import static io.cucumber.junit.platform.engine.Constants.PLUGIN_PROPERTY_NAME;
+
+@Suite
+@IncludeEngines("cucumber")
+@SelectClasspathResource("features")
+@ConfigurationParameter(key = PLUGIN_PROPERTY_NAME, value = "pretty")
+@ConfigurationParameter(key = GLUE_PROPERTY_NAME, value = "fr.iut_fbleau.but3.dev62.mylibrary.features")
+public class RunCucumberTest {
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/features/client/CustomerSteps.java

@@ -0,0 +1,223 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.features.client;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.CustomerInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.entity.Customer;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.CustomerNotFoundException;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.IllegalCustomerPointException;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.NotValidCustomerException;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.repository.CustomerRepository;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.usecase.CustomerUseCase;
+import io.cucumber.datatable.DataTable;
+import io.cucumber.java.en.And;
+import io.cucumber.java.en.Given;
+import io.cucumber.java.en.Then;
+import io.cucumber.java.en.When;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.UUID;
+
+public class CustomerSteps {
+
+  private final CustomerRepository customerRepository = new CustomerRepository();
+  private final CustomerUseCase customerUseCase = new CustomerUseCase(customerRepository);
+
+  private final Map<String, UUID> customerPhoneUUID = new HashMap<>();
+  private UUID customerRegistration;
+  private Optional<CustomerDTO> customerByPhoneNumber;
+  private Customer updatedCustomer;
+  private IllegalCustomerPointException illegalCustomerPointException;
+  private NotValidCustomerException notValidCustomerException;
+
+  @Given("the system has the following customers:")
+  public void theSystemHasTheFollowingCustomers(DataTable dataTable) {
+    int size = customerRepository.findAll().size();
+
+    if (size > 0) {
+      customerRepository.deleteAll();
+    }
+
+    List<Map<String, String>> customers = dataTable.asMaps(String.class, String.class);
+
+    for (Map<String, String> customer : customers) {
+      String numeroTelephone = customer.get("numeroTelephone");
+      Customer newCustomer = Customer.builder()
+          .firstName(customer.get("prenom"))
+          .lastName(customer.get("nom"))
+          .phoneNumber(numeroTelephone)
+          .loyaltyPoints(Integer.parseInt(customer.get("pointsFidelite")))
+          .build();
+      Customer save = customerRepository.save(newCustomer);
+      customerPhoneUUID.put(numeroTelephone, save.getId());
+    }
+
+    assertEquals(customers.size(), customerRepository.findAll().size());
+  }
+
+  @When("I create a new customer with the following information:")
+  public void iCreateANewCustomerWithTheFollowingInformation(DataTable dataTable) throws NotValidCustomerException {
+    List<Map<String, String>> rows = dataTable.asMaps(String.class, String.class);
+
+    Map<String, String> customerInfo = rows.getFirst();
+
+    CustomerInfo newCustomer = new CustomerInfo(
+        customerInfo.get("prenom"),
+        customerInfo.get("nom"),
+        customerInfo.get("numeroTelephone")
+    );
+
+    customerRegistration = customerUseCase.registerCustomer(newCustomer);
+  }
+
+  @And("the system now has {int} customers")
+  public void theSystemNowHasCustomers(int numberOfCustomers) {
+    assertEquals(numberOfCustomers, customerRepository.findAll().size());
+  }
+
+  @And("the customer has {int} loyalty points")
+  public void theCustomerHasLoyaltyPoints(int loyaltyPoints) {
+    Customer customer = customerRepository.findById(customerRegistration).orElseThrow();
+    assertEquals(loyaltyPoints, customer.getLoyaltyPoints());
+  }
+
+  @Then("a new customer is created")
+  public void aNewCustomerIsCreated() {
+    assertNotNull(customerRegistration);
+  }
+
+  @When("I request the customer with phone number {string}")
+  public void iRequestTheCustomerWithPhoneNumber(String phoneNumber) {
+    customerByPhoneNumber = customerUseCase.findCustomerByPhoneNumber(phoneNumber);
+  }
+
+  @Then("I receive the following customer information:")
+  public void iReceiveTheFollowingCustomerInformation(DataTable dataTable) {
+    List<Map<String, String>> customers = dataTable.asMaps(String.class, String.class);
+    Map<String, String> customerInfo = customers.getFirst();
+    assertTrue(customerByPhoneNumber.isPresent());
+    CustomerDTO customerDTO = customerByPhoneNumber.get();
+    assertEquals(customerInfo.get("prenom"), customerDTO.getFirstName());
+    assertEquals(customerInfo.get("nom"), customerDTO.getLastName());
+    assertEquals(customerInfo.get("numeroTelephone"), customerDTO.getPhoneNumber());
+  }
+
+  @When("I update customer {string} with the following information:")
+  public void iUpdateCustomerWithTheFollowingInformation(String phoneNumber, DataTable dataTable)
+      throws CustomerNotFoundException, NotValidCustomerException {
+    List<Map<String, String>> rows = dataTable.asMaps(String.class, String.class);
+
+    Map<String, String> customerData = rows.getFirst();
+    CustomerInfo customerInfo = new CustomerInfo(
+        customerData.get("prenom"),
+        customerData.get("nom"),
+        customerData.get("numeroTelephone")
+    );
+    UUID uuid = customerPhoneUUID.get(phoneNumber);
+    customerUseCase.updateCustomer(uuid, customerInfo);
+  }
+
+  @Then("the customer {string} has the following updated information:")
+  public void theCustomerHasTheFollowingUpdatedInformation(String phoneNumber, DataTable dataTable) {
+    List<Map<String, String>> rows = dataTable.asMaps(String.class, String.class);
+
+    Map<String, String> updatedDate = rows.getFirst();
+
+    UUID uuid = customerPhoneUUID.get(phoneNumber);
+    updatedCustomer = customerRepository.findById(uuid).orElseThrow();
+    assertEquals(updatedDate.get("numeroTelephone"), updatedCustomer.getPhoneNumber());
+    assertEquals(updatedDate.get("prenom"), updatedCustomer.getFirstName());
+    assertEquals(updatedDate.get("nom"), updatedCustomer.getLastName());
+  }
+
+  @And("the loyalty points remain unchanged at {int}")
+  public void theLoyaltyPointsRemainUnchangedAt(int expectedLoyaltyPoint) {
+    assertEquals(expectedLoyaltyPoint, updatedCustomer.getLoyaltyPoints());
+  }
+
+  @When("I delete the customer with phone number {string}")
+  public void iDeleteTheCustomerWithPhoneNumber(String phoneNumber) throws CustomerNotFoundException {
+    UUID uuid = customerPhoneUUID.get(phoneNumber);
+    customerUseCase.deleteCustomer(uuid);
+  }
+
+  @Then("the customer {string} is removed from the system")
+  public void theCustomerIsRemovedFromTheSystem(String phoneNumber) {
+    UUID uuid = customerPhoneUUID.get(phoneNumber);
+    assertFalse(customerRepository.existsById(uuid));
+  }
+
+  @When("I add {int} loyalty points to customer {string}")
+  public void iAddLoyaltyPointsToCustomer(int loyaltyPointToAdd, String phoneNumber) throws CustomerNotFoundException {
+    UUID uuid = customerPhoneUUID.get(phoneNumber);
+    customerUseCase.addLoyaltyPoints(uuid, loyaltyPointToAdd);
+  }
+
+  @Then("customer {string} now has {int} loyalty points")
+  public void customerNowHasLoyaltyPoints(String phoneNumber, int expectedLoyaltyPoints) {
+    UUID uuid = customerPhoneUUID.get(phoneNumber);
+    Customer customer = customerRepository.findById(uuid).orElseThrow();
+    assertEquals(expectedLoyaltyPoints, customer.getLoyaltyPoints());
+  }
+
+  @When("I deduct {int} loyalty points from customer {string} for a purchase")
+  public void iDeductLoyaltyPointsFromCustomerForAPurchase(int pointsToRemove, String phoneNumber) throws CustomerNotFoundException, IllegalCustomerPointException {
+    UUID uuid = customerPhoneUUID.get(phoneNumber);
+    customerUseCase.subtractLoyaltyPoints(uuid, pointsToRemove);
+  }
+
+  @When("I try to create a new customer with the following information:")
+  public void iTryToCreateANewCustomerWithTheFollowingInformation(DataTable ddataTable) {
+    List<Map<String, String>> rows = ddataTable.asMaps(String.class, String.class);
+
+    Map<String, String> customerInfo = rows.getFirst();
+
+    CustomerInfo newCustomer = new CustomerInfo(
+        customerInfo.get("prenom"),
+        customerInfo.get("nom"),
+        customerInfo.get("numeroTelephone")
+    );
+
+    notValidCustomerException = assertThrows(NotValidCustomerException.class, () -> customerUseCase.registerCustomer(newCustomer));
+  }
+
+  @Then("the creation fails")
+  public void theCreationFails() {
+    assertNotNull(notValidCustomerException);
+  }
+
+
+  @And("I receive an error for validation customer message containing {string}")
+  public void iReceiveAnErrorMessageContaining(String errorMessage) {
+    assertEquals(errorMessage, notValidCustomerException.getMessage());
+  }
+
+  @And("the system still has {int} customers")
+  public void theSystemStillHasCustomers(int expectedNumberOfUser) {
+    assertEquals(expectedNumberOfUser, customerRepository.findAll().size());
+  }
+
+  @When("I try to deduct {int} loyalty points from customer {string} for a purchase")
+  public void iTryToDeductLoyaltyPointsFromCustomerForAPurchase(int points, String phoneNumber) {
+    UUID uuid = customerPhoneUUID.get(phoneNumber);
+    illegalCustomerPointException = assertThrows(IllegalCustomerPointException.class, () -> customerUseCase.subtractLoyaltyPoints(uuid, points));
+  }
+
+  @Then("the deduction fails")
+  public void theDeductionFails() {
+    assertNotNull(illegalCustomerPointException);
+  }
+
+  @And("I receive an error for illegal customer exception message containing {string}")
+  public void iReceiveAnErrorForIllegalCustomerExceptionMessageContaining(String errorMessage) {
+    assertEquals(errorMessage, illegalCustomerPointException.getMessage());
+  }
+
+}

src/test/resources/features/client.feature

@@ -0,0 +1,60 @@
+# language: en
+
+Feature: Manage customer accounts
+
+  Background:
+    Given the system has the following customers:
+      | prenom | nom    | numeroTelephone | pointsFidelite |
+      | Marie  | Dupont | 0612345678      | 100            |
+      | Jean   | Martin | 0687654321      | 50             |
+      | Sophie | Dubois | 0698765432      | 0              |
+
+  Scenario: Create a new customer account
+    When I create a new customer with the following information:
+      | prenom | nom     | numeroTelephone |
+      | Pierre | Lambert | 0611223344      |
+    Then a new customer is created
+    And the customer has 0 loyalty points
+    And the system now has 4 customers
+
+  Scenario: Retrieve a customer by ID
+    When I request the customer with phone number "0612345678"
+    Then I receive the following customer information:
+      | prenom | nom    | numeroTelephone | pointsFidelite |
+      | Marie  | Dupont | 0612345678      | 100            |
+
+  Scenario: Update a customer's information
+    When I update customer "0687654321" with the following information:
+      | prenom | nom     | numeroTelephone |
+      | Jean   | Bernard | 0666666666      |
+    Then the customer "0687654321" has the following updated information:
+      | prenom | nom     | numeroTelephone |
+      | Jean   | Bernard | 0666666666      |
+    And the loyalty points remain unchanged at 50
+
+  Scenario: Delete a customer
+    When I delete the customer with phone number "0698765432"
+    Then the customer "0698765432" is removed from the system
+    And the system now has 2 customers
+
+  Scenario: Add loyalty points to a customer
+    When I add 25 loyalty points to customer "0687654321"
+    Then customer "0687654321" now has 75 loyalty points
+
+  Scenario: Deduct loyalty points for a purchase
+    When I deduct 30 loyalty points from customer "0612345678" for a purchase
+    Then customer "0612345678" now has 70 loyalty points
+
+  Scenario: Attempt to create a customer with invalid phone number
+    When I try to create a new customer with the following information:
+      | prenom | nom   | numeroTelephone |
+      | Thomas | Petit | abcdefgh        |
+    Then the creation fails
+    And I receive an error for validation customer message containing "Phone number is not valid"
+    And the system still has 3 customers
+
+  Scenario: Attempt to deduct more loyalty points than available
+    When I try to deduct 150 loyalty points from customer "0687654321" for a purchase
+    Then the deduction fails
+    And I receive an error for illegal customer exception message containing "Cannot remove 150 points from 50 points"
+    And customer "0687654321" now has 50 loyalty points