Correctly create meetings based off their repeatable values. This commit will break the change function as well as the deletion function, hence calling them will result in an exception.

Author: Konstantin Pankratov

server/src/main/java/com/studybuddies/server/domain/ChangeType.java

@@ -0,0 +1,6 @@
+package com.studybuddies.server.domain;
+
+public enum ChangeType {
+  SERIES,
+  OCCURRENCE
+}

server/src/main/java/com/studybuddies/server/domain/MeetingEntity.java

@@ -8,6 +8,7 @@
 import jakarta.persistence.ManyToOne;
 import jakarta.persistence.Table;
 import java.time.LocalDateTime;
+import java.util.UUID;
 import lombok.AllArgsConstructor;
 import lombok.Builder;
 import lombok.Getter;
@@ -22,9 +23,12 @@
 @AllArgsConstructor
 @NoArgsConstructor
 public class MeetingEntity {
+
   @Id
-  @GeneratedValue(strategy = GenerationType.IDENTITY)
-  Long id;
+  @GeneratedValue(strategy = GenerationType.UUID)
+  UUID id;
+
+  UUID superId;
 
   @Column(nullable = false)
   String title;

server/src/main/java/com/studybuddies/server/persistance/MeetingRepository.java

@@ -1,10 +1,14 @@
 package com.studybuddies.server.persistance;
 
 import com.studybuddies.server.domain.MeetingEntity;
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
 import org.springframework.data.repository.CrudRepository;
 import org.springframework.stereotype.Repository;
 
 @Repository
-public interface MeetingRepository extends CrudRepository<MeetingEntity, Long> {
-    void deleteById(Long id);
+public interface MeetingRepository extends CrudRepository<MeetingEntity, UUID> {
+    void deleteById(UUID id);
+    List<Optional<MeetingEntity>> findBySuperId(UUID superId);
 }

server/src/main/java/com/studybuddies/server/services/MeetingCreationService.java

@@ -0,0 +1,109 @@
+package com.studybuddies.server.services;
+
+import com.studybuddies.server.domain.MeetingEntity;
+import com.studybuddies.server.domain.Repeat;
+import com.studybuddies.server.domain.UserEntity;
+import com.studybuddies.server.web.dto.MeetingCreationRequest;
+import com.studybuddies.server.web.mapper.MeetingMapper;
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+import java.time.Month;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+@Service
+@RequiredArgsConstructor
+public class MeetingCreationService {
+  private final MeetingMapper meetingMapper;
+  private final UserService userService;
+
+  private LocalDateTime endTime;
+
+  public List<MeetingEntity> createMeetingInstances(
+      MeetingCreationRequest meetingCreationRequest,
+      String uuid
+  ) {
+    List<MeetingEntity> meetingEntities = new ArrayList<>();
+    setEndTime();
+
+    UUID superUUID = UUID.randomUUID();
+
+    MeetingEntity baseMeeting = meetingMapper.meetingCreationRequestToMeetingEntity(meetingCreationRequest);
+    UserEntity creator = userService.findByUUID(UUIDService.parseUUID(uuid));
+    baseMeeting.setCreator(creator);
+    baseMeeting.setSuperId(superUUID);
+    meetingEntities.add(baseMeeting);
+
+    while(shouldCreateMeeting(baseMeeting)) {
+      MeetingEntity newMeeting = cloneMeetingEntity(baseMeeting);
+      updateMeeting(newMeeting);
+      meetingEntities.add(newMeeting);
+      baseMeeting = newMeeting;
+    }
+
+    return meetingEntities;
+  }
+
+  private void updateMeeting(MeetingEntity meetingEntity) {
+    LocalDateTime startDate = meetingEntity.getDate_from();
+    LocalDateTime endDate = meetingEntity.getDate_until();
+
+    switch(meetingEntity.getRepeatable()) {
+      case DAILY:
+        meetingEntity.setDate_from(startDate.plusDays(1));
+        meetingEntity.setDate_until(endDate.plusDays(1));
+        break;
+      case WEEKLY:
+        meetingEntity.setDate_from(startDate.plusWeeks(1));
+        meetingEntity.setDate_until(endDate.plusWeeks(1));
+        break;
+      case MONTHLY:
+        meetingEntity.setDate_from(startDate.plusMonths(1));
+        meetingEntity.setDate_until(endDate.plusMonths(1));
+        break;
+      default:
+        throw new IllegalArgumentException("Invalid repeatable");
+    }
+  }
+
+  private boolean shouldCreateMeeting(MeetingEntity meetingEntity) {
+    if(meetingEntity.getRepeatable() == Repeat.NEVER) {
+      return false;
+    }
+    return meetingEntity.getDate_from().isBefore(endTime);
+
+  }
+
+  private void setEndTime() {
+    LocalDate now = LocalDate.now();
+    Month endMonth;
+
+    boolean semester =
+        now.getMonth().compareTo(Month.FEBRUARY) < 0 || now.getMonth().compareTo(Month.OCTOBER) > 0;
+
+    if(semester) {
+      endMonth = Month.FEBRUARY;
+    } else {
+      endMonth = Month.OCTOBER;
+    }
+
+    endTime = LocalDate.of(LocalDate.now().getYear(), endMonth.getValue(), 1).atStartOfDay();
+  }
+
+
+  private MeetingEntity cloneMeetingEntity(MeetingEntity meetingEntity) {
+    return MeetingEntity.builder()
+        .superId(meetingEntity.getSuperId())
+        .title(meetingEntity.getTitle())
+        .description(meetingEntity.getDescription())
+        .date_from(meetingEntity.getDate_from())
+        .date_until(meetingEntity.getDate_until())
+        .repeatable(meetingEntity.getRepeatable())
+        .place(meetingEntity.getPlace())
+        .creator(meetingEntity.getCreator())
+        .build();
+  }
+}

server/src/main/java/com/studybuddies/server/services/MeetingService.java

@@ -2,19 +2,21 @@
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.studybuddies.server.domain.ChangeType;
 import com.studybuddies.server.domain.MeetingEntity;
-import com.studybuddies.server.domain.UserEntity;
 import com.studybuddies.server.persistance.MeetingRepository;
 import com.studybuddies.server.services.exceptions.InvalidUUIDException;
 import com.studybuddies.server.services.exceptions.MeetingNotFoundException;
 import com.studybuddies.server.web.dto.MeetingChangeRequest;
 import com.studybuddies.server.web.dto.MeetingCreationRequest;
 import com.studybuddies.server.web.dto.MeetingResponse;
 import com.studybuddies.server.web.mapper.MeetingMapper;
-import com.studybuddies.server.web.mapper.MeetingMapperUtils;
 import jakarta.transaction.Transactional;
 import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
 import lombok.AllArgsConstructor;
+import org.apache.commons.lang3.NotImplementedException;
 import org.springframework.stereotype.Service;
 
 import java.util.Optional;
@@ -26,24 +28,33 @@ public class MeetingService {
   private final MeetingMapper meetingMapper;
   private final MeetingRepository meetingRepository;
   private final UserService userService;
-  private final MeetingMapperUtils meetingMapperUtils;
+  private final MeetingCreationService meetingCreationService;
 
   @Transactional
-  public Long saveMeetingToDatabase(MeetingCreationRequest mcr, String uuid) {
-    MeetingEntity meetingEntity = meetingMapper.meetingCreationRequestToMeetingEntity(mcr);
-    UserEntity creator = userService.findByUUID(UUIDService.parseUUID(uuid));
-    meetingEntity.setCreator(creator);
-    return meetingRepository.save(meetingEntity).getId();
+  public UUID createMeetings(MeetingCreationRequest mcr, String uuid) {
+    List<MeetingEntity> meetingEntities = meetingCreationService.createMeetingInstances(mcr, uuid);
+    meetingRepository.saveAll(meetingEntities);
+
+    return meetingEntities.get(0).getSuperId();
   }
 
   @Transactional
-  public void changeMeetingInDatabase(Long id, MeetingChangeRequest meetingChangeRequest, String uuid) {
-    Optional<MeetingEntity> requestResult = meetingRepository.findById(id);
+  public void changeMeetingInDatabase(UUID id, MeetingChangeRequest meetingChangeRequest, String uuid, ChangeType changeType) {
+   if(true) throw new NotImplementedException("Not implemented correctly");
+
+    List<Optional<MeetingEntity>> requestResult;
+
+    if(changeType == ChangeType.OCCURRENCE) {
+      requestResult = List.of(meetingRepository.findById(id));
+    } else {
+      requestResult = meetingRepository.findBySuperId(id);
+    }
 
     if (requestResult.isEmpty()) {
       throw new MeetingNotFoundException("");
     }
-    MeetingEntity meetingEntity = requestResult.get();
+
+    MeetingEntity meetingEntity = requestResult.get(0).get();
 
     if (!meetingEntity.getCreator().getUuid().equals(UUIDService.parseUUID(uuid))) {
       throw new MeetingNotFoundException("");
@@ -56,30 +67,38 @@ public void changeMeetingInDatabase(Long id, MeetingChangeRequest meetingChangeR
       }
 
     MeetingEntity changedMeetingEntity = meetingMapper.meetingChangeRequestToMeetingEntity(meetingChangeRequest);
-    MergingService.mergeObjects(changedMeetingEntity, meetingEntity);
+
+    for(var targetMeeting : requestResult) {
+      MergingService.mergeObjects(changedMeetingEntity, targetMeeting.get());
+    }
 
     meetingMapper.validate(meetingEntity);
     meetingRepository.save(meetingEntity);
   }
 
   @Transactional
-  public String retrieveMeetingFromDatabase(Long id) {
+  public String retrieveMeetingFromDatabase(UUID superId) {
     ObjectMapper mapper = new ObjectMapper();
+    List<MeetingResponse> responses = new ArrayList<>();
     try {
-      if (id == null) {
+      if (superId == null) {
         ArrayList<MeetingResponse> meetings = findAllMeetingEntities();
         return mapper.writeValueAsString(meetings);
       }
-      MeetingEntity meeting = meetingRepository.findById(id)
-          .orElseThrow(() -> new MeetingNotFoundException(""));
-      return mapper.writeValueAsString(meetingMapper.meetingEntityToMeetingResponse(meeting));
+      List<Optional<MeetingEntity>> meetings = meetingRepository.findBySuperId(superId);
+
+      for(Optional<MeetingEntity> meetingEntity : meetings) {
+        responses.add(meetingMapper.meetingEntityToMeetingResponse(meetingEntity.get()));
+      }
+      return mapper.writeValueAsString(responses);
     } catch (JsonProcessingException e) {
       return "Error processing data";
     }
   }
 
   @Transactional
-  public void deleteMeetingFromDatabase(Long id, String uuid) {
+  public void deleteMeetingFromDatabase(UUID id, String uuid) {
+    if(true) throw new NotImplementedException("Not implemented correctly");
     MeetingEntity meeting = meetingRepository.findById(id)
             .orElseThrow(() -> new MeetingNotFoundException(""));
 

server/src/main/java/com/studybuddies/server/services/MergingService.java

@@ -6,6 +6,9 @@
 
 @Service
 public class MergingService {
+
+  private MergingService() {}
+
   public static void mergeObjects(Object source, Object target) {
         if (source == null || target == null) {
             throw new IllegalArgumentException("Source and target objects must not be null");

server/src/main/java/com/studybuddies/server/web/MeetingController.java

@@ -1,11 +1,14 @@
 package com.studybuddies.server.web;
 
+import com.studybuddies.server.domain.ChangeType;
 import com.studybuddies.server.web.dto.MeetingChangeRequest;
 import com.studybuddies.server.web.dto.MeetingCreationRequest;
 import com.studybuddies.server.services.MeetingService;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.validation.Valid;
+import jakarta.validation.constraints.NotNull;
 import java.net.URI;
+import java.util.UUID;
 import lombok.AllArgsConstructor;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
@@ -23,7 +26,7 @@ public ResponseEntity<?> createMeeting(
       @Valid @RequestBody MeetingCreationRequest meetingCreationRequest,
       HttpServletRequest request
   ) {
-    Long meetingId = meetingService.saveMeetingToDatabase(meetingCreationRequest,
+    UUID meetingId = meetingService.createMeetings(meetingCreationRequest,
         request.getUserPrincipal().getName());
 
     HttpHeaders returnHeader = new HttpHeaders();
@@ -33,25 +36,26 @@ public ResponseEntity<?> createMeeting(
 
   @PutMapping
   public ResponseEntity<?> changeMeeting(
-      @RequestParam Long id,
+      @RequestParam UUID id,
+      @RequestParam ChangeType changeType,
       @Valid @RequestBody MeetingChangeRequest meetingChangeRequest,
       HttpServletRequest request
   ) {
-    meetingService.changeMeetingInDatabase(id, meetingChangeRequest, request.getUserPrincipal().getName());
+    meetingService.changeMeetingInDatabase(id, meetingChangeRequest, request.getUserPrincipal().getName(), changeType);
     return new ResponseEntity<>(HttpStatus.OK);
   }
 
   @GetMapping
   public ResponseEntity<?> getMeeting(
-      @RequestParam(required = false) Long id
+      @RequestParam(required = false) UUID id
   ) {
     String response = meetingService.retrieveMeetingFromDatabase(id);
     return ResponseEntity.status(HttpStatus.OK).body(response);
   }
 
   @DeleteMapping
   public ResponseEntity<?> deleteMeeting(
-      @RequestParam Long id,
+      @RequestParam UUID id,
       HttpServletRequest request
   ) {
     meetingService.deleteMeetingFromDatabase(id, request.getUserPrincipal().getName());

server/src/main/java/com/studybuddies/server/web/dto/MeetingResponse.java

@@ -4,7 +4,8 @@
 
 public class MeetingResponse {
     @NotBlank
-    public Long id;
+    public String id;
+    public String superId;
     @NotBlank
     public String title;
     public String description;

server/src/main/java/com/studybuddies/server/web/mapper/MeetingMapper.java

@@ -23,6 +23,7 @@ public interface MeetingMapper {
   MeetingEntity meetingCreationRequestToMeetingEntity(MeetingCreationRequest meetingCreationRequest);
 
   @Mapping(source = "id", target = "id")
+  @Mapping(source = "superId", target = "superId")
   @Mapping(source = "title", target = "title")
   @Mapping(source = "description", target = "description")
   @Mapping(source = "place", target = "place")