feat : 홈화면 추천 스터디

src/main/java/com/gamzabat/algohub/feature/group/studygroup/repository/GroupMemberRepository.java

@@ -1,11 +1,13 @@
 package com.gamzabat.algohub.feature.group.studygroup.repository;
 
+import java.time.LocalDate;
 import java.util.List;
 import java.util.Optional;
 
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.Modifying;
 import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
 
 import com.gamzabat.algohub.feature.group.studygroup.domain.GroupMember;
 import com.gamzabat.algohub.feature.group.studygroup.domain.StudyGroup;
@@ -31,4 +33,13 @@ public interface GroupMemberRepository extends JpaRepository<GroupMember, Long>
 	@Modifying
 	@Query("delete from GroupMember gm where gm.studyGroup = :studyGroup")
 	void deleteAllByStudyGroup(StudyGroup studyGroup);
+
+	@Query("SELECT COUNT(gm) FROM GroupMember gm WHERE gm.studyGroup = :studyGroup AND gm.joinDate BETWEEN :start AND :end")
+	Integer countByStudyGroupAndJoinDateBetween(@Param("studyGroup") StudyGroup studyGroup,
+		@Param("start") LocalDate start, @Param("end") LocalDate end);
+
+	@Query("SELECT COUNT(gm) FROM GroupMember gm WHERE gm.studyGroup = :studyGroup AND gm.joinDate < :date")
+	Integer countByStudyGroupAndJoinDateBefore(@Param("studyGroup") StudyGroup studyGroup,
+		@Param("date") LocalDate date);
+
 }

src/main/java/com/gamzabat/algohub/feature/problem/repository/ProblemRepository.java

@@ -9,6 +9,7 @@
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.Modifying;
 import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
 
 import com.gamzabat.algohub.feature.group.studygroup.domain.StudyGroup;
 import com.gamzabat.algohub.feature.problem.domain.Problem;
@@ -62,4 +63,8 @@ AND EXISTS (
 	@Modifying
 	@Query("update Problem p set p.deletedAt = CURRENT_TIMESTAMP where p.studyGroup = :studyGroup")
 	void deleteAllByStudyGroup(StudyGroup studyGroup);
+
+	@Query("SELECT p FROM Problem p WHERE p.studyGroup = :studyGroup AND p.startDate BETWEEN :start AND :end AND p.deletedAt IS NULL")
+	List<Problem> findAllByStudyGroupAndStartDateBetween(@Param("studyGroup") StudyGroup studyGroup,
+		@Param("start") LocalDate start, @Param("end") LocalDate end);
 }

src/main/java/com/gamzabat/algohub/feature/recommendation/controller/RecommendationController.java

@@ -0,0 +1,33 @@
+package com.gamzabat.algohub.feature.recommendation.controller;
+
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.gamzabat.algohub.common.annotation.AuthedUser;
+import com.gamzabat.algohub.feature.recommendation.dto.HomeRecommendationsResponse;
+import com.gamzabat.algohub.feature.recommendation.service.RecommendationService;
+import com.gamzabat.algohub.feature.user.domain.User;
+
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.tags.Tag;
+import lombok.RequiredArgsConstructor;
+
+@RestController
+@RequiredArgsConstructor
+@RequestMapping("/api")
+@Tag(name = "추천 API", description = "홈 화면 추천 스터디 API")
+public class RecommendationController {
+
+	private final RecommendationService recommendationService;
+
+	@GetMapping("/home/recommendations")
+	@Operation(summary = "홈 추천 스터디 조회 API")
+	public ResponseEntity<HomeRecommendationsResponse> getHomeRecommendations(
+		@AuthedUser User user
+	) {
+		HomeRecommendationsResponse response = recommendationService.getHomeRecommendations(user.getId());
+		return ResponseEntity.ok().body(response);
+	}
+}

src/main/java/com/gamzabat/algohub/feature/recommendation/domain/GroupActivityWeekly.java

@@ -0,0 +1,69 @@
+package com.gamzabat.algohub.feature.recommendation.domain;
+
+import java.time.LocalDateTime;
+
+import com.gamzabat.algohub.feature.group.studygroup.domain.StudyGroup;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.Table;
+import jakarta.validation.constraints.NotNull;
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Entity
+@Table(name = "group_activity_weekly")
+@Getter
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@AllArgsConstructor
+@Builder
+public class GroupActivityWeekly {
+
+	@Id
+	@GeneratedValue(strategy = GenerationType.IDENTITY)
+	private Long id;
+
+	@ManyToOne(fetch = FetchType.LAZY)
+	@JoinColumn(name = "study_group_id", nullable = false)
+	private StudyGroup studyGroup;
+
+	@Column(name = "week_start", nullable = false)
+	private LocalDateTime weekStart;
+
+	@Column(name = "week_end", nullable = false)
+	private LocalDateTime weekEnd;
+
+	@Column(name = "submissions", nullable = false)
+	private Integer submissions;
+
+	@Column(name = "comments", nullable = false)
+	private Integer comments;
+
+	@Column(name = "active_score", nullable = false)
+	private Double activeScore;
+
+	@Builder
+	public GroupActivityWeekly(
+		@NotNull StudyGroup studyGroup,
+		@NotNull LocalDateTime weekStart,
+		@NotNull LocalDateTime weekEnd,
+		@NotNull Integer submissions,
+		@NotNull Integer comments,
+		@NotNull Double activeScore) {
+		this.studyGroup = studyGroup;
+		this.weekStart = weekStart;
+		this.weekEnd = weekEnd;
+		this.submissions = submissions;
+		this.comments = comments;
+		this.activeScore = activeScore;
+	}
+}

src/main/java/com/gamzabat/algohub/feature/recommendation/domain/GroupDifficultyMonthlyRolling.java

@@ -0,0 +1,57 @@
+package com.gamzabat.algohub.feature.recommendation.domain;
+
+import java.time.LocalDateTime;
+
+import com.gamzabat.algohub.feature.group.studygroup.domain.StudyGroup;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.Table;
+import jakarta.validation.constraints.NotNull;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Entity
+@Table(name = "group_difficulty_monthly_rolling")
+@Getter
+@NoArgsConstructor
+@AllArgsConstructor
+public class GroupDifficultyMonthlyRolling {
+
+	@Id
+	@GeneratedValue(strategy = GenerationType.IDENTITY)
+	private Long id;
+
+	@ManyToOne(fetch = FetchType.LAZY)
+	@JoinColumn(name = "study_group_id", nullable = false)
+	private StudyGroup studyGroup;
+
+	@Column(name = "window_start", nullable = false)
+	private LocalDateTime windowStart;
+
+	@Column(name = "window_end", nullable = false)
+	private LocalDateTime windowEnd;
+
+	@Column(name = "avg_difficulty", nullable = false)
+	private Double avgDifficulty;
+
+	@Builder
+	public GroupDifficultyMonthlyRolling(
+		@NotNull StudyGroup studyGroup,
+		@NotNull LocalDateTime windowStart,
+		@NotNull LocalDateTime windowEnd,
+		@NotNull Double avgDifficulty) {
+		this.studyGroup = studyGroup;
+		this.windowStart = windowStart;
+		this.windowEnd = windowEnd;
+		this.avgDifficulty = avgDifficulty;
+	}
+}

src/main/java/com/gamzabat/algohub/feature/recommendation/domain/GroupJoinMonthlyRolling.java

@@ -0,0 +1,67 @@
+package com.gamzabat.algohub.feature.recommendation.domain;
+
+import java.time.LocalDateTime;
+
+import com.gamzabat.algohub.feature.group.studygroup.domain.StudyGroup;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.Table;
+import jakarta.validation.constraints.NotNull;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Entity
+@Table(name = "group_join_monthly_rolling")
+@Getter
+@NoArgsConstructor
+@AllArgsConstructor
+public class GroupJoinMonthlyRolling {
+
+	@Id
+	@GeneratedValue(strategy = GenerationType.IDENTITY)
+	private Long id;
+
+	@ManyToOne(fetch = FetchType.LAZY)
+	@JoinColumn(name = "study_group_id", nullable = false)
+	private StudyGroup studyGroup;
+
+	@Column(name = "window_start", nullable = false)
+	private LocalDateTime windowStart;
+
+	@Column(name = "window_end", nullable = false)
+	private LocalDateTime windowEnd;
+
+	@Column(name = "new_members", nullable = false)
+	private Integer newMembers;
+
+	@Column(name = "members_before_window", nullable = false)
+	private Integer membersBeforeWindow;
+
+	@Column(name = "join_rate", nullable = false)
+	private Double joinRate;
+
+	@Builder
+	public GroupJoinMonthlyRolling(
+		@NotNull StudyGroup studyGroup,
+		@NotNull LocalDateTime windowStart,
+		@NotNull LocalDateTime windowEnd,
+		@NotNull Integer newMembers,
+		@NotNull Integer membersBeforeWindow,
+		@NotNull Double joinRate) {
+		this.studyGroup = studyGroup;
+		this.windowStart = windowStart;
+		this.windowEnd = windowEnd;
+		this.newMembers = newMembers;
+		this.membersBeforeWindow = membersBeforeWindow;
+		this.joinRate = joinRate;
+	}
+}

src/main/java/com/gamzabat/algohub/feature/recommendation/domain/StudyGroupTag.java

@@ -0,0 +1,75 @@
+package com.gamzabat.algohub.feature.recommendation.domain;
+
+import java.time.LocalDateTime;
+
+import com.gamzabat.algohub.feature.group.studygroup.domain.StudyGroup;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.EnumType;
+import jakarta.persistence.Enumerated;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.Table;
+import jakarta.validation.constraints.NotNull;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Entity
+@Table(name = "study_group_tag")
+@Getter
+@NoArgsConstructor
+@AllArgsConstructor
+public class StudyGroupTag {
+
+	@Id
+	@GeneratedValue(strategy = GenerationType.IDENTITY)
+	private Long id;
+
+	@ManyToOne(fetch = FetchType.LAZY)
+	@JoinColumn(name = "study_group_id", nullable = false)
+	private StudyGroup studyGroup;
+
+	@Enumerated(EnumType.STRING)
+	@Column(name = "tag_type", nullable = false, length = 64)
+	private TagType tagType;
+
+	@Column(name = "score", nullable = false)
+	private Double score;
+
+	@Column(name = "first_achieved_at", nullable = false)
+	private LocalDateTime firstAchievedAt;
+
+	@Column(name = "window_start", nullable = false)
+	private LocalDateTime windowStart;
+
+	@Column(name = "window_end", nullable = false)
+	private LocalDateTime windowEnd;
+
+	@Column(name = "computed_at", nullable = false)
+	private LocalDateTime computedAt;
+
+	@Builder
+	public StudyGroupTag(
+		@NotNull StudyGroup studyGroup,
+		@NotNull TagType tagType,
+		@NotNull Double score,
+		@NotNull LocalDateTime firstAchievedAt,
+		@NotNull LocalDateTime windowStart,
+		@NotNull LocalDateTime windowEnd,
+		@NotNull LocalDateTime computedAt) {
+		this.studyGroup = studyGroup;
+		this.tagType = tagType;
+		this.score = score;
+		this.firstAchievedAt = firstAchievedAt;
+		this.windowStart = windowStart;
+		this.windowEnd = windowEnd;
+		this.computedAt = computedAt;
+	}
+}

src/main/java/com/gamzabat/algohub/feature/recommendation/domain/TagType.java

@@ -0,0 +1,7 @@
+package com.gamzabat.algohub.feature.recommendation.domain;
+
+public enum TagType {
+    MOST_ACTIVE_THIS_WEEK,
+    HIGH_JOIN_RATE_RECENT,
+    SIMILAR_DIFFICULTY
+}