추천 콘텐츠 시간 감쇠 적용

홈 API의 크리에이터 랭킹 응답에서 팔로우 여부를 일괄 조회로 계산한다.

src/main/kotlin/kr/co/vividnext/sodalive/api/home/HomeService.kt

@@ -7,6 +7,7 @@ import kr.co.vividnext.sodalive.chat.character.translate.AiCharacterTranslationR
 import kr.co.vividnext.sodalive.content.AudioContentMainItem
 import kr.co.vividnext.sodalive.content.AudioContentService
 import kr.co.vividnext.sodalive.content.ContentType
+import kr.co.vividnext.sodalive.content.SortType
 import kr.co.vividnext.sodalive.content.main.GetAudioContentRankingItem
 import kr.co.vividnext.sodalive.content.main.banner.AudioContentBannerService
 import kr.co.vividnext.sodalive.content.main.curation.AudioContentCurationService
@@ -22,7 +23,6 @@ import kr.co.vividnext.sodalive.i18n.LangContext
 import kr.co.vividnext.sodalive.live.room.LiveRoomService
 import kr.co.vividnext.sodalive.live.room.LiveRoomStatus
 import kr.co.vividnext.sodalive.member.Member
-import kr.co.vividnext.sodalive.member.MemberService
 import kr.co.vividnext.sodalive.query.recommend.RecommendChannelQueryService
 import kr.co.vividnext.sodalive.rank.ContentRankingSortType
 import kr.co.vividnext.sodalive.rank.RankingRepository
@@ -34,10 +34,10 @@ import java.time.DayOfWeek
 import java.time.LocalDateTime
 import java.time.ZoneId
 import java.time.temporal.TemporalAdjusters
+import kotlin.math.pow
 
 @Service
 class HomeService(
-    private val memberService: MemberService,
     private val liveRoomService: LiveRoomService,
     private val auditionService: AuditionService,
     private val seriesService: ContentSeriesService,
@@ -64,8 +64,19 @@ class HomeService(
     companion object {
         private const val RECOMMEND_TARGET_SIZE = 30
         private const val RECOMMEND_MAX_ATTEMPTS = 3
+        private const val TIME_DECAY_HALF_LIFE_RANK = 30.0
     }
 
+    private data class RecommendBucket(
+        val offset: Long,
+        val limit: Long
+    )
+
+    private data class DecayCandidate(
+        val item: AudioContentMainItem,
+        val rank: Int
+    )
+
     fun fetchData(
         timezone: String,
         isAdultContentVisible: Boolean,
@@ -84,25 +95,20 @@ class HomeService(
             timezone = timezone
         )
 
-        val creatorRanking = rankingRepository
-            .getCreatorRankings()
-            .filter {
-                if (memberId != null) {
-                    !memberService.isBlocked(blockedMemberId = memberId, memberId = it.id!!)
-                } else {
-                    true
-                }
-            }
-            .map {
-                val followerCount = explorerQueryRepository.getNotificationUserIds(it.id!!).size
-                val follow = if (memberId != null) {
-                    explorerQueryRepository.isFollow(it.id!!, memberId = memberId)
-                } else {
-                    false
-                }
+        val creatorRankingMembers = rankingRepository.getCreatorRankings(memberId = memberId)
+        val creatorRankingIds = creatorRankingMembers.mapNotNull { it.id }
+        val followedCreatorIds = if (memberId != null) {
+            explorerQueryRepository.getFollowedCreatorIds(creatorRankingIds, memberId)
+        } else {
+            emptySet()
+        }
 
-                it.toExplorerSectionCreator(imageHost, follow, followerCount = followerCount)
-            }
+        val creatorRanking = creatorRankingMembers.map { creator ->
+            val creatorId = creator.id!!
+            val follow = memberId != null && followedCreatorIds.contains(creatorId)
+
+            creator.toExplorerSectionCreator(imageHost, follow)
+        }
 
         val latestContentThemeList = contentThemeService.getActiveThemeOfContent(
             isAdult = isAdult,
@@ -111,17 +117,12 @@ class HomeService(
         )
 
         val latestContentList = contentService.getLatestContentByTheme(
+            memberId = memberId,
             theme = latestContentThemeList,
             contentType = contentType,
             isFree = false,
             isAdult = isAdult
-        ).filter {
-            if (memberId != null) {
-                !memberService.isBlocked(blockedMemberId = memberId, memberId = it.creatorId)
-            } else {
-                true
-            }
-        }
+        )
 
         val translatedLatestContentList = getTranslatedContentList(contentList = latestContentList)
 
@@ -237,6 +238,7 @@ class HomeService(
         }
 
         val freeContentList = contentService.getLatestContentByTheme(
+            memberId = memberId,
             theme = contentThemeService.getActiveThemeOfContent(
                 isAdult = isAdult,
                 isFree = true,
@@ -246,34 +248,28 @@ class HomeService(
             isFree = true,
             isAdult = isAdult,
             orderByRandom = true
-        ).filter {
-            if (memberId != null) {
-                !memberService.isBlocked(blockedMemberId = memberId, memberId = it.creatorId)
-            } else {
-                true
-            }
-        }
+        )
 
         val translatedFreeContentList = getTranslatedContentList(contentList = freeContentList)
 
         // 포인트 사용가능 콘텐츠 리스트 - 랜덤으로 가져오기 (DB에서 isPointAvailable 조건 적용)
         val pointAvailableContentList = contentService.getLatestContentByTheme(
+            memberId = memberId,
             theme = emptyList(),
             contentType = contentType,
             isFree = false,
             isAdult = isAdult,
             orderByRandom = true,
             isPointAvailableOnly = true
-        ).filter {
-            if (memberId != null) {
-                !memberService.isBlocked(blockedMemberId = memberId, memberId = it.creatorId)
-            } else {
-                true
-            }
-        }
+        )
 
         val translatedPointAvailableContentList = getTranslatedContentList(contentList = pointAvailableContentList)
 
+        val excludeContentIds = (
+            translatedLatestContentList.map { it.contentId } +
+                translatedContentRanking.map { it.contentId }
+            ).distinct()
+
         val curationList = curationService.getContentCurationList(
             tabId = 3L, // 기존에 사용하던 단편 탭의 큐레이션을 사용
             isAdult = isAdult,
@@ -299,7 +295,8 @@ class HomeService(
             recommendContentList = getRecommendContentList(
                 isAdultContentVisible = isAdultContentVisible,
                 contentType = contentType,
-                member = member
+                member = member,
+                excludeContentIds = excludeContentIds
             ),
             curationList = curationList
         )
@@ -326,17 +323,12 @@ class HomeService(
         }
 
         val contentList = contentService.getLatestContentByTheme(
+            memberId = memberId,
             theme = themeList,
             contentType = contentType,
             isFree = false,
             isAdult = isAdult
-        ).filter {
-            if (memberId != null) {
-                !memberService.isBlocked(blockedMemberId = memberId, memberId = it.creatorId)
-            } else {
-                true
-            }
-        }
+        )
 
         return getTranslatedContentList(contentList = contentList)
     }
@@ -412,46 +404,101 @@ class HomeService(
         return dayToSeriesPublishedDaysOfWeek[zonedDateTime.dayOfWeek] ?: SeriesPublishedDaysOfWeek.RANDOM
     }
 
-    // 추천 콘텐츠 조회 로직은 변경 가능성을 고려하여 별도 메서드로 추출한다.
     fun getRecommendContentList(
         isAdultContentVisible: Boolean,
         contentType: ContentType,
-        member: Member?
+        member: Member?,
+        excludeContentIds: List<Long> = emptyList()
     ): List<AudioContentMainItem> {
         val memberId = member?.id
         val isAdult = member?.auth != null && isAdultContentVisible
 
-        // Set + List 조합으로 중복 제거 및 순서 보존, 각 시도마다 limit=60으로 조회
-        val seen = HashSet<Long>(RECOMMEND_TARGET_SIZE * 2)
-        val result = ArrayList<AudioContentMainItem>(RECOMMEND_TARGET_SIZE)
-        var attempt = 0
-        while (attempt < RECOMMEND_MAX_ATTEMPTS && result.size < RECOMMEND_TARGET_SIZE) {
-            attempt += 1
-            val batch = contentService.getLatestContentByTheme(
-                theme = emptyList(), // 특정 테마에 종속되지 않도록 전체에서 랜덤 조회
-                contentType = contentType,
-                offset = 0,
-                limit = (RECOMMEND_TARGET_SIZE * RECOMMEND_MAX_ATTEMPTS).toLong(), // 60개 조회
-                isFree = false,
-                isAdult = isAdult,
-                orderByRandom = true
-            ).filter {
-                if (memberId != null) {
-                    !memberService.isBlocked(blockedMemberId = memberId, memberId = it.creatorId)
-                } else {
-                    true
-                }
-            }
+        // 3개의 버킷(최근/중간/과거)에서 후보군을 조회한 뒤, 시간감쇠 점수 기반으로 샘플링한다.
+        val buckets = listOf(
+            RecommendBucket(offset = 0L, limit = 50L),
+            RecommendBucket(offset = 50L, limit = 100L),
+            RecommendBucket(offset = 150L, limit = 150L)
+        )
 
-            for (item in batch) {
+        val result = mutableListOf<AudioContentMainItem>()
+        val seenIds = excludeContentIds.toMutableSet()
+
+        repeat(RECOMMEND_MAX_ATTEMPTS) {
+            if (result.size >= RECOMMEND_TARGET_SIZE) return@repeat
+
+            val remaining = RECOMMEND_TARGET_SIZE - result.size
+            val targetPerBucket = maxOf(1, (remaining + buckets.size - 1) / buckets.size)
+
+            for (bucket in buckets) {
                 if (result.size >= RECOMMEND_TARGET_SIZE) break
-                if (seen.add(item.contentId)) {
-                    result.add(item)
+
+                val batch = contentService.getLatestContentByTheme(
+                    memberId = memberId,
+                    theme = emptyList(),
+                    contentType = contentType,
+                    offset = bucket.offset,
+                    limit = bucket.limit,
+                    sortType = SortType.NEWEST,
+                    isFree = false,
+                    isAdult = isAdult,
+                    orderByRandom = false,
+                    excludeContentIds = seenIds.toList()
+                )
+
+                val selected = pickByTimeDecay(
+                    batch = batch,
+                    targetSize = minOf(targetPerBucket, RECOMMEND_TARGET_SIZE - result.size),
+                    seenIds = seenIds
+                )
+                if (selected.isNotEmpty()) {
+                    result.addAll(selected)
                 }
             }
         }
 
-        return getTranslatedContentList(contentList = result)
+        return getTranslatedContentList(contentList = result.take(RECOMMEND_TARGET_SIZE).shuffled())
+    }
+
+    private fun pickByTimeDecay(
+        batch: List<AudioContentMainItem>,
+        targetSize: Int,
+        seenIds: MutableSet<Long>
+    ): List<AudioContentMainItem> {
+        if (targetSize <= 0 || batch.isEmpty()) return emptyList()
+
+        val candidates = batch
+            .asSequence()
+            .filterNot { seenIds.contains(it.contentId) }
+            .mapIndexed { index, item -> DecayCandidate(item = item, rank = index) }
+            .toMutableList()
+
+        if (candidates.isEmpty()) return emptyList()
+
+        val selected = mutableListOf<AudioContentMainItem>()
+        while (selected.size < targetSize && candidates.isNotEmpty()) {
+            val selectedIndex = selectByWeight(candidates)
+            val chosen = candidates.removeAt(selectedIndex).item
+            if (seenIds.add(chosen.contentId)) {
+                selected.add(chosen)
+            }
+        }
+
+        return selected
+    }
+
+    private fun selectByWeight(candidates: List<DecayCandidate>): Int {
+        val weights = candidates.map { 0.5.pow(it.rank / TIME_DECAY_HALF_LIFE_RANK) }
+        val totalWeight = weights.sum()
+
+        var randomPoint = Math.random() * totalWeight
+        for (index in weights.indices) {
+            randomPoint -= weights[index]
+            if (randomPoint <= 0) {
+                return index
+            }
+        }
+
+        return candidates.lastIndex
     }
 
     /**

src/main/kotlin/kr/co/vividnext/sodalive/content/AudioContentRepository.kt

@@ -178,6 +178,7 @@ interface AudioContentQueryRepository {
     fun findContentIdAndHashTagId(contentId: Long, hashTagId: Int): AudioContentHashTag?
 
     fun getLatestContentByTheme(
+        memberId: Long? = null,
         theme: List<String>,
         contentType: ContentType,
         offset: Long,
@@ -186,7 +187,8 @@ interface AudioContentQueryRepository {
         isFree: Boolean,
         isAdult: Boolean,
         orderByRandom: Boolean = false,
-        isPointAvailableOnly: Boolean = false
+        isPointAvailableOnly: Boolean = false,
+        excludeContentIds: List<Long> = emptyList()
     ): List<AudioContentMainItem>
 
     fun findContentByCurationId(
@@ -1319,6 +1321,7 @@ class AudioContentQueryRepositoryImpl(
     }
 
     override fun getLatestContentByTheme(
+        memberId: Long?,
         theme: List<String>,
         contentType: ContentType,
         offset: Long,
@@ -1327,8 +1330,17 @@ class AudioContentQueryRepositoryImpl(
         isFree: Boolean,
         isAdult: Boolean,
         orderByRandom: Boolean,
-        isPointAvailableOnly: Boolean
+        isPointAvailableOnly: Boolean,
+        excludeContentIds: List<Long>
     ): List<AudioContentMainItem> {
+        val blockMemberCondition = if (memberId != null) {
+            blockMember.member.id.eq(member.id)
+                .and(blockMember.isActive.isTrue)
+                .and(blockMember.blockedMember.id.eq(memberId))
+        } else {
+            null
+        }
+
         var where = audioContent.isActive.isTrue
             .and(audioContent.duration.isNotNull)
             .and(
@@ -1366,6 +1378,30 @@ class AudioContentQueryRepositoryImpl(
             where = where.and(audioContent.isPointAvailable.isTrue)
         }
 
+        if (excludeContentIds.isNotEmpty()) {
+            where = where.and(audioContent.id.notIn(excludeContentIds))
+        }
+
+        var select = queryFactory
+            .select(
+                QAudioContentMainItem(
+                    audioContent.id,
+                    member.id,
+                    audioContent.title,
+                    audioContent.coverImage.prepend("/").prepend(imageHost),
+                    member.nickname,
+                    audioContent.isPointAvailable
+                )
+            )
+            .from(audioContent)
+            .innerJoin(audioContent.member, member)
+            .innerJoin(audioContent.theme, audioContentTheme)
+
+        if (memberId != null) {
+            where = where.and(blockMember.id.isNull)
+            select = select.leftJoin(blockMember).on(blockMemberCondition)
+        }
+
         val orderBy = if (orderByRandom) {
             Expressions.numberTemplate(Double::class.java, "function('rand')").asc()
         } else {
@@ -1387,20 +1423,7 @@ class AudioContentQueryRepositoryImpl(
             }
         }
 
-        return queryFactory
-            .select(
-                QAudioContentMainItem(
-                    audioContent.id,
-                    member.id,
-                    audioContent.title,
-                    audioContent.coverImage.prepend("/").prepend(imageHost),
-                    member.nickname,
-                    audioContent.isPointAvailable
-                )
-            )
-            .from(audioContent)
-            .innerJoin(audioContent.member, member)
-            .innerJoin(audioContent.theme, audioContentTheme)
+        return select
             .where(where)
             .offset(offset)
             .limit(limit)

src/main/kotlin/kr/co/vividnext/sodalive/content/AudioContentService.kt

@@ -1198,6 +1198,7 @@ class AudioContentService(
 
     @Transactional(readOnly = true)
     fun getLatestContentByTheme(
+        memberId: Long? = null,
         theme: List<String>,
         contentType: ContentType,
         offset: Long = 0,
@@ -1206,7 +1207,8 @@ class AudioContentService(
         isFree: Boolean = false,
         isAdult: Boolean = false,
         orderByRandom: Boolean = false,
-        isPointAvailableOnly: Boolean = false
+        isPointAvailableOnly: Boolean = false,
+        excludeContentIds: List<Long> = emptyList()
     ): List<AudioContentMainItem> {
         /**
          * - AS-IS theme은 한글만 처리하도록 되어 있음
@@ -1221,6 +1223,7 @@ class AudioContentService(
         )
 
         val contentList = repository.getLatestContentByTheme(
+            memberId = memberId,
             theme = normalizedTheme,
             contentType = contentType,
             offset = offset,
@@ -1229,7 +1232,8 @@ class AudioContentService(
             isFree = isFree,
             isAdult = isAdult,
             orderByRandom = orderByRandom,
-            isPointAvailableOnly = isPointAvailableOnly
+            isPointAvailableOnly = isPointAvailableOnly,
+            excludeContentIds = excludeContentIds
         )
 
         val contentIds = contentList.map { it.contentId }

src/main/kotlin/kr/co/vividnext/sodalive/explorer/ExplorerQueryRepository.kt

@@ -637,6 +637,23 @@ class ExplorerQueryRepository(
             .fetchOne() ?: false
     }
 
+    fun getFollowedCreatorIds(creatorIds: List<Long>, memberId: Long): Set<Long> {
+        if (creatorIds.isEmpty()) {
+            return emptySet()
+        }
+
+        return queryFactory
+            .select(creatorFollowing.creator.id)
+            .from(creatorFollowing)
+            .where(
+                creatorFollowing.isActive.isTrue
+                    .and(creatorFollowing.creator.id.`in`(creatorIds))
+                    .and(creatorFollowing.member.id.eq(memberId))
+            )
+            .fetch()
+            .toSet()
+    }
+
     fun getCreatorCheers(cheersId: Long): CreatorCheers? {
         return queryFactory
             .selectFrom(creatorCheers)

src/main/kotlin/kr/co/vividnext/sodalive/query/recommend/RecommendChannelQueryRepository.kt

@@ -9,6 +9,7 @@ import kr.co.vividnext.sodalive.content.like.QAudioContentLike.audioContentLike
 import kr.co.vividnext.sodalive.member.MemberRole
 import kr.co.vividnext.sodalive.member.QMember.member
 import kr.co.vividnext.sodalive.member.auth.QAuth.auth
+import kr.co.vividnext.sodalive.member.block.QBlockMember.blockMember
 import org.springframework.beans.factory.annotation.Value
 import org.springframework.stereotype.Repository
 
@@ -19,7 +20,19 @@ class RecommendChannelQueryRepository(
     @Value("\${cloud.aws.cloud-front.host}")
     private val imageHost: String
 ) {
-    fun getRecommendChannelList(isAdult: Boolean, contentType: ContentType): List<RecommendChannelResponse> {
+    fun getRecommendChannelList(
+        memberId: Long?,
+        isAdult: Boolean,
+        contentType: ContentType
+    ): List<RecommendChannelResponse> {
+        val blockMemberCondition = if (memberId != null) {
+            blockMember.member.id.eq(member.id)
+                .and(blockMember.isActive.isTrue)
+                .and(blockMember.blockedMember.id.eq(memberId))
+        } else {
+            null
+        }
+
         var where = member.role.eq(MemberRole.CREATOR)
             .and(audioContent.isActive.isTrue)
 
@@ -39,7 +52,7 @@ class RecommendChannelQueryRepository(
             }
         }
 
-        return queryFactory
+        var select = queryFactory
             .select(
                 QRecommendChannelResponse(
                     member.id,
@@ -52,6 +65,13 @@ class RecommendChannelQueryRepository(
             .from(member)
             .innerJoin(auth).on(auth.member.id.eq(member.id))
             .innerJoin(audioContent).on(audioContent.member.id.eq(member.id))
+
+        if (memberId != null) {
+            where = where.and(blockMember.id.isNull)
+            select = select.leftJoin(blockMember).on(blockMemberCondition)
+        }
+
+        return select
             .where(where)
             .groupBy(member.id)
             .having(audioContent.id.count().goe(3))
@@ -60,14 +80,26 @@ class RecommendChannelQueryRepository(
             .fetch()
     }
 
-    fun getContentsByCreatorIdLikeDesc(creatorId: Long, isAdult: Boolean): List<RecommendChannelContentItem> {
+    fun getContentsByCreatorIdLikeDesc(
+        creatorId: Long,
+        memberId: Long?,
+        isAdult: Boolean
+    ): List<RecommendChannelContentItem> {
+        val blockMemberCondition = if (memberId != null) {
+            blockMember.member.id.eq(audioContent.member.id)
+                .and(blockMember.isActive.isTrue)
+                .and(blockMember.blockedMember.id.eq(memberId))
+        } else {
+            null
+        }
+
         var where = audioContent.member.id.eq(creatorId)
 
         if (!isAdult) {
             where = where.and(audioContent.isAdult.isFalse)
         }
 
-        return queryFactory
+        var select = queryFactory
             .select(
                 QRecommendChannelContentItem(
                     audioContent.id,
@@ -88,6 +120,13 @@ class RecommendChannelQueryRepository(
                 audioContentComment.audioContent.id.eq(audioContent.id)
                     .and(audioContentComment.isActive.isTrue)
             )
+
+        if (memberId != null) {
+            where = where.and(blockMember.id.isNull)
+            select = select.leftJoin(blockMember).on(blockMemberCondition)
+        }
+
+        return select
             .where(where)
             .groupBy(audioContent.id)
             .orderBy(audioContentLike.id.countDistinct().desc())

src/main/kotlin/kr/co/vividnext/sodalive/query/recommend/RecommendChannelQueryService.kt

@@ -18,6 +18,7 @@ class RecommendChannelQueryService(private val repository: RecommendChannelQuery
         contentType: ContentType
     ): List<RecommendChannelResponse> {
         val recommendChannelList = repository.getRecommendChannelList(
+            memberId = memberId,
             isAdult = isAdult,
             contentType = contentType
         )
@@ -25,6 +26,7 @@ class RecommendChannelQueryService(private val repository: RecommendChannelQuery
         return recommendChannelList.map {
             it.contentList = repository.getContentsByCreatorIdLikeDesc(
                 creatorId = it.channelId,
+                memberId = memberId,
                 isAdult = isAdult
             )
 

src/main/kotlin/kr/co/vividnext/sodalive/rank/RankingRepository.kt

@@ -33,11 +33,29 @@ class RankingRepository(
     @Value("\${cloud.aws.cloud-front.host}")
     private val imageHost: String
 ) {
-    fun getCreatorRankings(): List<Member> {
-        return queryFactory
+    fun getCreatorRankings(memberId: Long? = null): List<Member> {
+        val blockMemberCondition = if (memberId != null) {
+            blockMember.member.id.eq(member.id)
+                .and(blockMember.isActive.isTrue)
+                .and(blockMember.blockedMember.id.eq(memberId))
+        } else {
+            null
+        }
+
+        var select = queryFactory
             .select(member)
             .from(creatorRanking)
             .innerJoin(creatorRanking.member, member)
+
+        if (memberId != null) {
+            select = select.leftJoin(blockMember).on(blockMemberCondition)
+        }
+
+        if (memberId != null) {
+            select = select.where(blockMember.id.isNull)
+        }
+
+        return select
             .orderBy(creatorRanking.ranking.asc())
             .fetch()
     }

src/main/kotlin/kr/co/vividnext/sodalive/rank/RankingService.kt

@@ -9,7 +9,6 @@ import kr.co.vividnext.sodalive.creator.admin.content.series.Series
 import kr.co.vividnext.sodalive.creator.admin.content.series.SeriesPublishedDaysOfWeek
 import kr.co.vividnext.sodalive.creator.admin.content.series.SeriesState
 import kr.co.vividnext.sodalive.explorer.GetExplorerSectionResponse
-import kr.co.vividnext.sodalive.member.MemberService
 import org.springframework.beans.factory.annotation.Value
 import org.springframework.stereotype.Service
 import java.time.LocalDateTime
@@ -17,7 +16,6 @@ import java.time.LocalDateTime
 @Service
 class RankingService(
     private val repository: RankingRepository,
-    private val memberService: MemberService,
     private val seriesContentRepository: ContentSeriesContentRepository,
 
     @Value("\${cloud.aws.cloud-front.host}")
@@ -25,14 +23,7 @@ class RankingService(
 ) {
     fun getCreatorRanking(memberId: Long?, rankingDate: String): GetExplorerSectionResponse {
         val creatorRankings = repository
-            .getCreatorRankings()
-            .filter {
-                if (memberId != null) {
-                    !memberService.isBlocked(blockedMemberId = memberId, memberId = it.id!!)
-                } else {
-                    true
-                }
-            }
+            .getCreatorRankings(memberId = memberId)
             .map { it.toExplorerSectionCreator(imageHost) }
 
         return GetExplorerSectionResponse(