🚀 2단계 - 수강신청(도메인 모델)

README.md

@@ -6,4 +6,25 @@
 * 모든 피드백을 완료하면 다음 단계를 도전하고 앞의 과정을 반복한다.
 
 ## 온라인 코드 리뷰 과정
-* [텍스트와 이미지로 살펴보는 온라인 코드 리뷰 과정](https://github.com/next-step/nextstep-docs/tree/master/codereview)
+* [텍스트와 이미지로 살펴보는 온라인 코드 리뷰 과정](https://github.com/next-step/nextstep-docs/tree/master/codereview)
+
+## 2단계 요구사항
+- 강의
+- [ ] 과정(Course)은 기수 단위로 운영하며, 여러 개의 강의(Session)를 가질 수 있다.
+  - [x] 강의는 시작일과 종료일을 가진다.
+  - [x] 강의는 강의 커버 이미지 정보를 가진다.
+  - [ ] 강의는 무료 강의와 유료 강의로 나뉜다.
+    - [ ] 무료 강의는 최대 수강 인원 제한이 없다.
+    - [x] 유료 강의는 강의 최대 수강 인원을 초과할 수 없다.
+    - [x] 유료 강의는 수강생이 결제한 금액과 수강료가 일치할 때 수강 신청이 가능하다.
+  - [x] 강의 상태는 준비중, 모집중, 종료 3가지 상태를 가진다.
+  - [x] 강의 수강신청은 강의 상태가 모집중일 때만 가능하다.
+  - [ ] 유료 강의의 경우 결제는 이미 완료한 것으로 가정하고 이후 과정을 구현한다.
+
+- 이미지
+- [x] 이미지 크기는 1MB 이하여야 한다.
+- [x] 이미지 타입은 gif, jpg(jpeg 포함), png, svg만 허용한다.
+- [x] 이미지의 width는 300픽셀, height는 200픽셀 이상이어야 하며, width와 height의 비율은 3:2여야 한다.
+
+- 결제
+  - [ ] 결제를 완료한 결제 정보는 payments 모듈을 통해 관리되며, 결제 정보는 Payment 객체에 담겨 반한된다.

src/main/java/nextstep/courses/CannotEnrollException.java

@@ -0,0 +1,7 @@
+package nextstep.courses;
+
+public class CannotEnrollException extends RuntimeException {
+    public CannotEnrollException(String message) {
+        super(message);
+    }
+}

src/main/java/nextstep/courses/InvalidImageException.java

@@ -0,0 +1,11 @@
+package nextstep.courses;
+
+public class InvalidImageException extends RuntimeException {
+    public InvalidImageException(String message) {
+        super(message);
+    }
+
+    public InvalidImageException(){
+
+    }
+}

src/main/java/nextstep/courses/domain/Course.java → src/main/java/nextstep/courses/domain/course/Course.java

@@ -1,4 +1,4 @@
-package nextstep.courses.domain;
+package nextstep.courses.domain.course;
 
 import java.time.LocalDateTime;
 

src/main/java/nextstep/courses/domain/CourseRepository.java → src/main/java/nextstep/courses/domain/course/CourseRepository.java

@@ -1,4 +1,4 @@
-package nextstep.courses.domain;
+package nextstep.courses.domain.course;
 
 public interface CourseRepository {
     int save(Course course);

src/main/java/nextstep/courses/domain/session/Enrollment.java

@@ -0,0 +1,51 @@
+package nextstep.courses.domain.session;
+
+import nextstep.users.domain.NsUser;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+public class Enrollment {
+    private final List<NsUser> users;
+    private final SessionCapacity sessionCapacity;
+
+    public Enrollment(List<NsUser> users, SessionCapacity sessionCapacity) {
+        this.users = users;
+        this.sessionCapacity = sessionCapacity;
+    }
+
+    public Enrollment(SessionCapacity sessionCapacity) {
+        this(new ArrayList<>(), sessionCapacity);
+    }
+
+    public Enrollment(int capacity) {
+        this(new ArrayList<>(), new SessionCapacity(capacity));
+    }
+
+    public Enrollment(List<NsUser> users) {
+        this(users, new SessionCapacity(0));
+    }
+
+    public void enroll(NsUser user) {
+        sessionCapacity.increase();
+        this.users.add(user);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(users);
+    }
+
+    @Override
+    public boolean equals(Object object) {
+        if (object == this) {
+            return true;
+        }
+        if (object == null || getClass() != object.getClass()) {
+            return false;
+        }
+        Enrollment enrollment = (Enrollment) object;
+        return Objects.equals(enrollment.users, this.users);
+    }
+}

src/main/java/nextstep/courses/domain/session/Session.java

@@ -0,0 +1,43 @@
+package nextstep.courses.domain.session;
+
+import nextstep.courses.CannotEnrollException;
+import nextstep.courses.strategy.PaymentStrategy;
+import nextstep.payments.domain.Payment;
+import nextstep.users.domain.NsUser;
+
+import java.time.LocalDate;
+
+public class Session {
+    private final SessionImage image;
+    private final SessionDate date;
+    private final SessionState state;
+    private final Enrollment enrollment;
+    private final PaymentStrategy paymentStrategy;
+
+    public Session(SessionImage image, SessionDate date, SessionState state, Enrollment enrollment, PaymentStrategy paymentStrategy) {
+        this.image = image;
+        this.date = date;
+        this.state = state;
+        this.enrollment = enrollment;
+        this.paymentStrategy = paymentStrategy;
+    }
+
+    public void applySession(NsUser user, LocalDate enrollDate, Payment payment) {
+        if (!canApply(enrollDate, payment)) {
+            throw new CannotEnrollException("등록 불가능한 상태입니다.");
+        }
+        this.enrollment.enroll(user);
+    }
+
+    private boolean canApply(LocalDate enrollDate, Payment payment) {
+        if (!state.canRecruit()) {
+            return false;
+        }
+
+        if (!date.isBefore(enrollDate)) {
+            return false;
+        }
+
+        return paymentStrategy.payable(payment);
+    }
+}

src/main/java/nextstep/courses/domain/session/SessionCapacity.java

@@ -0,0 +1,57 @@
+package nextstep.courses.domain.session;
+
+import nextstep.courses.CannotEnrollException;
+
+import java.util.Objects;
+
+public class SessionCapacity {
+    private static final int MIN_CAPACITY = 1;
+
+    private int capacity;
+    private final int maxCapacity;
+
+    public SessionCapacity(int capacity, int maxCapacity) {
+        this.capacity = capacity;
+        this.maxCapacity = maxCapacity;
+        checkValidCapacity();
+    }
+
+    public SessionCapacity(int maxCapacity) {
+        this(0, maxCapacity);
+    }
+
+    private void checkValidCapacity() {
+        if (maxCapacity < MIN_CAPACITY) {
+            throw new IllegalArgumentException();
+        }
+        isValidCapacity();
+    }
+
+    public void increase() {
+        capacity++;
+        isValidCapacity();
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(capacity, maxCapacity);
+    }
+
+    @Override
+    public boolean equals(Object object) {
+        if (object == this) {
+            return true;
+        }
+        if (object == null || getClass() != object.getClass()) {
+            return false;
+        }
+        SessionCapacity sessionCapacity = (SessionCapacity) object;
+        return sessionCapacity.capacity == this.capacity && sessionCapacity.maxCapacity == this.maxCapacity;
+    }
+
+    private void isValidCapacity(){
+        if(this.capacity > this.maxCapacity) {
+            throw new CannotEnrollException("최대 수용 인원을 현재 인원이 초과할 수 없다.");
+        }
+    }
+}

src/main/java/nextstep/courses/domain/session/SessionDate.java

@@ -0,0 +1,17 @@
+package nextstep.courses.domain.session;
+
+import java.time.LocalDate;
+
+public class SessionDate {
+    private final LocalDate startDate;
+    private final LocalDate endDate;
+
+    public SessionDate(LocalDate startDate, LocalDate endDate) {
+        this.startDate = startDate;
+        this.endDate = endDate;
+    }
+
+    public boolean isBefore(LocalDate date) {
+        return date.isBefore(startDate);
+    }
+}

src/main/java/nextstep/courses/domain/session/SessionImage.java

@@ -0,0 +1,59 @@
+package nextstep.courses.domain.session;
+
+import nextstep.courses.InvalidImageException;
+
+import java.util.Objects;
+
+public class SessionImage {
+    private static final int MAX_IMAGE_SIZE = 1000000;
+    private static final int MIN_WIDTH = 300;
+    private static final int MIN_HEIGHT = 200;
+    private static final double WIDTH_PER_HEIGHT = 1.5;
+
+    private final int width;
+    private final int height;
+    private final int size;
+    private final SessionImageType imageType;
+
+    public SessionImage(int width, int height, int size, String imageType) {
+        this(width, height, size, SessionImageType.of(imageType));
+    }
+
+    public SessionImage(int width, int height, int size, SessionImageType imageType) {
+        this.width = width;
+        this.height = height;
+        this.size = size;
+        this.imageType = imageType;
+        checkValidSessionImage();
+    }
+
+    private void checkValidSessionImage() {
+        if (this.width < MIN_WIDTH || this.height < MIN_HEIGHT) {
+            throw new InvalidImageException("이미지의 width는 300픽셀, height는 200픽셀 이상이어야 한다.");
+        }
+        if ((double) this.width / this.height != WIDTH_PER_HEIGHT) {
+            throw new InvalidImageException("이미지의 width, height의 비율은 3:2여야 한다.");
+        }
+
+        if (this.size > MAX_IMAGE_SIZE) {
+            throw new InvalidImageException("이미지의 크기는 1MB 이하여야 한다.");
+        }
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(width, height, size, imageType);
+    }
+
+    @Override
+    public boolean equals(Object object) {
+        if (object == this) {
+            return true;
+        }
+        if (object == null || getClass() != object.getClass()) {
+            return false;
+        }
+        SessionImage image = (SessionImage) object;
+        return Objects.equals(image.imageType, imageType) && image.width == width && image.height == height && image.size == size;
+    }
+}

src/main/java/nextstep/courses/domain/session/SessionImageType.java

@@ -0,0 +1,23 @@
+package nextstep.courses.domain.session;
+
+import nextstep.courses.InvalidImageException;
+
+import java.util.Arrays;
+
+public enum SessionImageType {
+    gif("gif"), jpg("jpg"), jpeg("jpeg"), png("png"), svg("svg");
+
+    private final String name;
+
+    SessionImageType(String name) {
+        this.name = name;
+    }
+
+    public static SessionImageType of(String name) {
+        return Arrays.stream(values())
+                .filter(type -> type.name.equals(name))
+                .findFirst()
+                .orElseThrow(InvalidImageException::new);
+
+    }
+}

src/main/java/nextstep/courses/domain/session/SessionState.java

@@ -0,0 +1,11 @@
+package nextstep.courses.domain.session;
+
+public enum SessionState {
+    PREPARING,
+    RECRUITING,
+    CLOSED;
+
+    public boolean canRecruit(){
+        return this == RECRUITING;
+    }
+}

src/main/java/nextstep/courses/infrastructure/JdbcCourseRepository.java

@@ -1,7 +1,7 @@
 package nextstep.courses.infrastructure;
 
-import nextstep.courses.domain.Course;
-import nextstep.courses.domain.CourseRepository;
+import nextstep.courses.domain.course.Course;
+import nextstep.courses.domain.course.CourseRepository;
 import org.springframework.jdbc.core.JdbcOperations;
 import org.springframework.jdbc.core.RowMapper;
 import org.springframework.stereotype.Repository;

src/main/java/nextstep/courses/strategy/FreePaymentStrategy.java

@@ -0,0 +1,10 @@
+package nextstep.courses.strategy;
+
+import nextstep.payments.domain.Payment;
+
+public class FreePaymentStrategy implements PaymentStrategy {
+    @Override
+    public boolean payable(Payment payment) {
+        return true;
+    }
+}

src/main/java/nextstep/courses/strategy/PaidPaymentStrategy.java

@@ -0,0 +1,18 @@
+package nextstep.courses.strategy;
+
+import nextstep.payments.domain.Payment;
+
+public class PaidPaymentStrategy implements PaymentStrategy {
+    private final long price;
+
+    public PaidPaymentStrategy(long price) {
+        this.price = price;
+    }
+
+    @Override
+    public boolean payable(Payment payment) {
+        if (payment.isSameAmount(price))
+            return true;
+        return false;
+    }
+}

src/main/java/nextstep/courses/strategy/PaymentStrategy.java

@@ -0,0 +1,7 @@
+package nextstep.courses.strategy;
+
+import nextstep.payments.domain.Payment;
+
+public interface PaymentStrategy {
+    boolean payable(Payment payment);
+}

src/main/java/nextstep/payments/domain/Payment.java

@@ -26,4 +26,8 @@ public Payment(String id, Long sessionId, Long nsUserId, Long amount) {
         this.amount = amount;
         this.createdAt = LocalDateTime.now();
     }
+
+    public boolean isSameAmount(long amount){
+        return amount == this.amount;
+    }
 }