🚀 2단계 - 수강신청(도메인 모델)

README.md

@@ -6,4 +6,26 @@
 * 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)
+
+# 수강 신청 기능 요구사항
+### Course
+과정(Course)은 기수 단위로 운영, 여러 개의 강의(Session)를 가질 수 있다.
+### Session
+강의는 시작일과 종료일을 가진다. (Period)
+강의는 강의 커버 이미지 정보를 가진다. (Image)
+### Image
+이미지 크기는 1MB 이하여야 한다.
+이미지 타입은 gif, jpg(jpeg 포함), png, svg만 허용한다.
+이미지의 width는 300픽셀, height는 200픽셀 이상이어야 하며, width와 height의 비율은 3:2여야 한다.
+### SessionType
+강의는 무료 강의와 유료 강의로 나뉜다.
+무료 강의는 최대 수강 인원 제한이 없다.
+유료 강의는 강의 최대 수강 인원을 초과할 수 없다.
+유료 강의는 수강생이 결제한 금액과 수강료가 일치할 때 수강 신청이 가능하다.
+### SessionStatus
+강의 상태는 준비중, 모집중, 종료 3가지 상태를 가진다.
+강의 수강신청은 강의 상태가 모집중일 때만 가능하다.
+유료 강의의 경우 결제는 이미 완료한 것으로 가정하고 이후 과정을 구현한다.
+### Payment
+결제를 완료한 결제 정보는 payments 모듈을 통해 관리되며, 결제 정보는 Payment 객체에 담겨 반한된다.

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

@@ -1,6 +1,7 @@
 package nextstep.courses.domain;
 
 import java.time.LocalDateTime;
+import java.util.List;
 
 public class Course {
     private Long id;
@@ -13,6 +14,8 @@ public class Course {
 
     private LocalDateTime updatedAt;
 
+    private List<Session> sessionList;
+
     public Course() {
     }
 

src/main/java/nextstep/courses/domain/FreeSessionType.java

@@ -0,0 +1,17 @@
+package nextstep.courses.domain;
+
+public class FreeSessionType implements SessionType {
+
+    private static final int ZERO = 0;
+
+    private final int pirce;
+
+    public FreeSessionType() {
+        this.pirce = ZERO;
+    }
+
+    public FreeSessionType registered() {
+        return new FreeSessionType();
+    }
+
+}

src/main/java/nextstep/courses/domain/ImageExtension.java

@@ -0,0 +1,5 @@
+package nextstep.courses.domain;
+
+public enum ImageExtension {
+    GIF, JPG, JPEG, PNG, SVG
+}

src/main/java/nextstep/courses/domain/PaidSessionType.java

@@ -0,0 +1,29 @@
+package nextstep.courses.domain;
+
+import nextstep.payments.domain.Payment;
+
+public class PaidSessionType implements SessionType {
+
+    private int maximumHeadCount;
+    private long price;
+
+    public PaidSessionType(int maximumHeadCount, long price) {
+        this.maximumHeadCount = maximumHeadCount;
+        this.price = price;
+    }
+
+    private void canRegistered(long payedPrice, int headCount) {
+        int nextHeadCount = headCount + 1;
+        if (maximumHeadCount < nextHeadCount) {
+            throw new IllegalArgumentException("인원수가 초과했습니다.");
+        }
+        if (payedPrice < this.price) {
+            throw new IllegalArgumentException("지불하신 금액이 모자랍니다.");
+        }
+    }
+
+    public PaidSessionType registered(long payedPrice, int headCount) {
+        canRegistered(payedPrice, headCount);
+        return new PaidSessionType(headCount + 1, this.price);
+    }
+}

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

@@ -0,0 +1,13 @@
+package nextstep.courses.domain;
+
+public class Session {
+
+    private Long id;
+    private SessionPeriod period;
+    private SessionImage image;
+    private SessionType type;
+    private SessionStatus status;
+    private int price;
+    private int headCount;
+
+}

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

@@ -0,0 +1,28 @@
+package nextstep.courses.domain;
+
+public class SessionImage {
+
+    private static final int ONE_MEGA_BYTE = 1_000_000;
+
+    private Integer capacity;
+    private ImageExtension extension;
+    private SessionImageSize size;
+
+    public SessionImage(int capacity, ImageExtension extension, int width, int height) {
+        validate(capacity);
+        this.capacity = capacity;
+        this.extension = extension;
+        this.size = new SessionImageSize(width, height);
+    }
+
+    private void validate(int capacity) {
+        capacityValidate(capacity);
+    }
+
+    private void capacityValidate(int capacity) {
+        if (ONE_MEGA_BYTE < capacity) {
+            throw new IllegalArgumentException(" 이미지 용량은 1MB 이하만 가능합니다. ");
+        }
+    }
+
+}

src/main/java/nextstep/courses/domain/SessionImageSize.java

@@ -0,0 +1,57 @@
+package nextstep.courses.domain;
+
+public class SessionImageSize {
+
+    private static final int WIDTH_RATIO = 3;
+    private static final int HEIGHT_RATIO = 2;
+    private static final int WIDTH_MAXIMUM = 300;
+    private static final int HEIGHT_MAXIMUM = 200;
+
+    private int width;
+    private int height;
+    private String ratio;
+
+    public SessionImageSize(int width, int height) {
+        validation(width, height);
+        this.width = width;
+        this.height = height;
+        this.ratio = calculateRatio();
+    }
+
+    private void validation(int width, int height) {
+        widthAndHeightValidate(width, height);
+        ratioValidate(width, height);
+    }
+
+    private void ratioValidate(int width, int height) {
+        if (WIDTH_RATIO != calculaateWidthRatio(width) && HEIGHT_RATIO != calculaateHeightRatio(height)) {
+            throw new IllegalArgumentException(" 이미지 비율을 3:2만 가능합니다.");
+        }
+    }
+
+    private void widthAndHeightValidate(int width, int height) {
+        if (width < WIDTH_MAXIMUM || height < HEIGHT_MAXIMUM) {
+            throw new IllegalArgumentException(" 이미지의 크기는 세로 300, 가로 200 픽셀 이상만 가능합니다. ");
+        }
+    }
+
+    private String calculateRatio() {
+        return calculaateWidthRatio(width) + ":" + calculaateHeightRatio(height);
+    }
+
+    private int calculaateWidthRatio(int width) {
+        int divided = width / 100;
+        if(WIDTH_RATIO != divided){
+            divided = divided / WIDTH_RATIO;
+        }
+        return divided;
+    }
+
+    private int calculaateHeightRatio(int height) {
+        int divided = height / 100;
+        if(HEIGHT_RATIO != divided){
+            divided = divided / HEIGHT_RATIO;
+        }
+        return divided;
+    }
+}

src/main/java/nextstep/courses/domain/SessionPeriod.java

@@ -0,0 +1,11 @@
+package nextstep.courses.domain;
+
+import java.time.LocalDateTime;
+
+public class SessionPeriod {
+
+    private LocalDateTime startAt;
+
+    private LocalDateTime endAt;
+
+}

src/main/java/nextstep/courses/domain/SessionStatus.java

@@ -0,0 +1,5 @@
+package nextstep.courses.domain;
+
+public enum SessionStatus {
+    PREPARING, RECRUITING, END
+}

src/main/java/nextstep/courses/domain/SessionType.java

@@ -0,0 +1,4 @@
+package nextstep.courses.domain;
+
+public interface SessionType {
+}

src/main/java/nextstep/qna/domain/Answer.java

@@ -79,9 +79,9 @@ public String toString() {
     }
 
     public Answer delete(NsUser writer) throws CannotDeleteException {
-        if (!this.isOwner(writer)) {
+        if (!isOwner(writer)) {
             throw new CannotDeleteException("다른 사람이 쓴 답변이 있어 삭제할 수 없습니다.");
         }
-        return this.setDeleted(true);
+        return setDeleted(true);
     }
 }

src/main/java/nextstep/qna/domain/Question.java

@@ -1,13 +1,14 @@
 package nextstep.qna.domain;
 
-import nextstep.qna.CannotDeleteException;
-import nextstep.users.domain.NsUser;
-
 import java.time.LocalDateTime;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.stream.Collectors;
+import nextstep.qna.CannotDeleteException;
+import nextstep.users.domain.NsUser;
 
 public class Question {
+
     private Long id;
 
     private String title;
@@ -88,13 +89,41 @@ public List<Answer> getAnswers() {
 
     @Override
     public String toString() {
-        return "Question [id=" + getId() + ", title=" + title + ", contents=" + contents + ", writer=" + writer + "]";
+        return "Question [id=" + getId() + ", title=" + title + ", contents=" + contents
+            + ", writer=" + writer + "]";
     }
 
-    public Question delete(NsUser writer) throws CannotDeleteException {
+    private Question deleteQuestion(NsUser writer) throws CannotDeleteException {
         if (!this.isOwner(writer)) {
             throw new CannotDeleteException("질문을 삭제할 권한이 없습니다.");
         }
         return this.setDeleted(true);
     }
+
+    private List<Answer> deleteAnswersOfThisQuestion(NsUser writer) {
+        return getAnswers().stream().map(answer -> {
+            try {
+                return answer.delete(writer);
+            } catch (CannotDeleteException e) {
+                throw new RuntimeException(e);
+            }
+        }).collect(Collectors.toList());
+    }
+
+    public List<DeleteHistory> deleteQuestionAndRelatedAnswer(NsUser writer, LocalDateTime now)
+        throws CannotDeleteException {
+        Question question = deleteQuestion(writer);
+        List<Answer> answers = deleteAnswersOfThisQuestion(writer);
+
+        List<DeleteHistory> deleteHistories = new ArrayList<>();
+        deleteHistories.add(
+            new DeleteHistory(ContentType.QUESTION, question.getId(), question.getWriter(), now));
+
+        for (Answer answer : answers) {
+            deleteHistories.add(
+                new DeleteHistory(ContentType.ANSWER, answer.getId(), answer.getWriter(), now));
+        }
+
+        return deleteHistories;
+    }
 }

src/main/java/nextstep/qna/service/DeleteHistoryService.java

@@ -1,21 +1,16 @@
 package nextstep.qna.service;
 
-import java.time.LocalDateTime;
-import java.util.ArrayList;
-import nextstep.qna.domain.Answer;
-import nextstep.qna.domain.ContentType;
+import java.util.List;
+import javax.annotation.Resource;
 import nextstep.qna.domain.DeleteHistory;
 import nextstep.qna.domain.DeleteHistoryRepository;
-import nextstep.qna.domain.Question;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Propagation;
 import org.springframework.transaction.annotation.Transactional;
 
-import javax.annotation.Resource;
-import java.util.List;
-
 @Service("deleteHistoryService")
 public class DeleteHistoryService {
+
     @Resource(name = "deleteHistoryRepository")
     private DeleteHistoryRepository deleteHistoryRepository;
 
@@ -24,16 +19,4 @@ public void saveAll(List<DeleteHistory> deleteHistories) {
         deleteHistoryRepository.saveAll(deleteHistories);
     }
 
-    public void saveAll(Question question, List<Answer> answers) {
-        List<DeleteHistory> deleteHistories = new ArrayList<>();
-        deleteHistories.add(
-            new DeleteHistory(ContentType.QUESTION, question.getId(), question.getWriter(),
-                LocalDateTime.now()));
-        for (Answer answer : answers) {
-            deleteHistories.add(
-                new DeleteHistory(ContentType.ANSWER, answer.getId(), answer.getWriter(),
-                    LocalDateTime.now()));
-        }
-        this.saveAll(deleteHistories);
-    }
 }

src/main/java/nextstep/qna/service/QnAService.java

@@ -1,13 +1,12 @@
 package nextstep.qna.service;
 
+import java.time.LocalDateTime;
 import java.util.List;
-import java.util.stream.Collectors;
 import javax.annotation.Resource;
 import nextstep.qna.CannotDeleteException;
 import nextstep.qna.NotFoundException;
-import nextstep.qna.domain.Answer;
 import nextstep.qna.domain.AnswerRepository;
-import nextstep.qna.domain.Question;
+import nextstep.qna.domain.DeleteHistory;
 import nextstep.qna.domain.QuestionRepository;
 import nextstep.users.domain.NsUser;
 import org.springframework.stereotype.Service;
@@ -27,18 +26,10 @@ public class QnAService {
 
     @Transactional
     public void deleteQuestion(NsUser loginUser, long questionId) throws CannotDeleteException {
-        Question deletedQuestion = questionRepository.findById(questionId)
+        List<DeleteHistory> deleteHistories = questionRepository.findById(questionId)
             .orElseThrow(NotFoundException::new)
-            .delete(loginUser);
+            .deleteQuestionAndRelatedAnswer(loginUser, LocalDateTime.now());
 
-        List<Answer> deletedAnswers = deletedQuestion.getAnswers().stream().map(answer -> {
-            try {
-                return answer.delete(loginUser);
-            } catch (CannotDeleteException e) {
-                throw new RuntimeException(e);
-            }
-        }).collect(Collectors.toList());
-
-        deleteHistoryService.saveAll(deletedQuestion, deletedAnswers);
+        deleteHistoryService.saveAll(deleteHistories);
     }
 }