[+] Game music popularity handler

src/main/java/icu/samnyan/aqua/sega/general/GameMusicPopularity.kt

@@ -0,0 +1,36 @@
+package icu.samnyan.aqua.sega.general
+
+import ext.*
+import icu.samnyan.aqua.net.db.AquaUserServices
+import org.springframework.scheduling.annotation.Scheduled
+import org.springframework.stereotype.Component
+import java.time.LocalDate
+
+@Component
+class GameMusicPopularity(val us: AquaUserServices) {
+    companion object {
+        val log = logger()
+
+        const val LOOK_BACK_DAYS: Long = 7
+        const val QUERY_LIMIT: Long = 50
+    }
+
+    data class PopularMusic(val musicId: Int, val weight: Long)
+    var ranking: Map<Str, List<PopularMusic>> = mapOf()
+
+    @Scheduled(fixedDelay = 3600_000)
+    fun refreshMusicRanking() {
+        // Get the play count of each music in the last N days
+        val after = LocalDate.now().minusDays(LOOK_BACK_DAYS).isoDate()
+
+        ranking = ls("chusan", "ongeki").associateWith { game ->
+            us.em.createNativeQuery("""
+                SELECT music_id, count(user_id) as count 
+                FROM ${game}_user_playlog_view
+                WHERE user_play_date >= '${after}'
+                GROUP BY music_id ORDER BY count DESC LIMIT ${QUERY_LIMIT};
+            """.trimIndent()).exec.map { PopularMusic(it[0]!!.int, it[1]!!.long) }
+                .also { log.info("Refreshed music ranking cache for $game: ${it.size} items") }
+        }
+    }
+}