feat(tournament): add Swiss-system tournament module

Implements the full tournament lifecycle: create, join, withdraw, start, round progression, and finish with Buchholz tiebreak standings. - REST resource covering all 11 endpoints from the OpenAPI spec - Swiss pairing algorithm with bye support - Per-bot NDJSON stream with targeted gameStart events (color field) - Game result ingestion via Redis writeback stream - H2-backed integration tests for resource and pairing service Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-05-29 00:46:56 +02:00
parent ae3ef766e8
commit 5c586b9003
27 changed files with 2205 additions and 0 deletions
@@ -0,0 +1,59 @@
+quarkus:
+  http:
+    port: 8088
+  application:
+    name: nowchess-tournament
+  redis:
+    hosts: redis://${REDIS_HOST:localhost}:${REDIS_PORT:6379}
+  rest-client:
+    core-service:
+      url: http://localhost:8080
+  datasource:
+    db-kind: h2
+    username: sa
+    password: ""
+    jdbc:
+      url: jdbc:h2:mem:nowchess-tournament;DB_CLOSE_DELAY=-1
+  hibernate-orm:
+    schema-management:
+      strategy: drop-and-create
+  smallrye-jwt:
+    enabled: true
+
+nowchess:
+  redis:
+    host: ${REDIS_HOST:localhost}
+    port: ${REDIS_PORT:6379}
+    prefix: ${REDIS_PREFIX:nowchess}
+  internal:
+    secret: ${INTERNAL_SECRET:123abc}
+
+mp:
+  jwt:
+    verify:
+      publickey:
+        location: keys/public.pem
+      issuer: nowchess
+
+"%deployed":
+  quarkus:
+    datasource:
+      db-kind: postgresql
+      username: ${DB_USER:nowchess}
+      password: ${DB_PASSWORD:nowchess}
+      jdbc:
+        url: ${DB_URL:jdbc:postgresql://localhost:5432/nowchess}
+    hibernate-orm:
+      schema-management:
+        strategy: update
+
+"%test":
+  quarkus:
+    datasource:
+      jdbc:
+        url: jdbc:h2:mem:nowchess-tournament;DB_CLOSE_DELAY=-1
+    hibernate-orm:
+      schema-management:
+        strategy: drop-and-create
+    arc:
+      exclude-types: de.nowchess.tournament.redis.GameResultStreamListener
@@ -0,0 +1,9 @@
+-----BEGIN PUBLIC KEY-----
+MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAxDsnsCAl0vQx7Vu9CLDZ
+g0SG05NgUzu9T+3DTEaHGq60T2uriO8BenwyvsF3BnDqTbKf4voohZ1DNfzdbT1J
+Fj8B62FrDmxcO+sp1/b5HUCJP6y2uSRCmzOHe5k7Pk1IEi72FgBpKXSRkFibRlVf
+634g7mgsPZAQ9PJEsv4Qvm05T9L6+Gmq6N3bMVLKRXs4RhDhaFbYH9GtUg1eI0yH
+YjGyRfqzW/nqVMstOLHt8CuPouq4p7eMzeDH3YHkxPm4GG5foCXMOd2DZrW0SCcr
+7dhFeNVWzQ2m53eOhBzNQX+v3pgjVStsePhBRt2LyGfwkNzmqDgqWsMzSHRMY+cn
+WQIDAQAB
+-----END PUBLIC KEY-----
@@ -0,0 +1,28 @@
+package de.nowchess.tournament.client
+
+import de.nowchess.security.{InternalClientHeadersFactory, InternalSecretClientFilter}
+import jakarta.ws.rs.*
+import jakarta.ws.rs.core.MediaType
+import org.eclipse.microprofile.rest.client.annotation.{RegisterClientHeaders, RegisterProvider}
+import org.eclipse.microprofile.rest.client.inject.RegisterRestClient
+
+case class CorePlayerInfo(id: String, displayName: String)
+case class CoreTimeControl(limitSeconds: Option[Int], incrementSeconds: Option[Int], daysPerMove: Option[Int])
+case class CoreCreateGameRequest(
+    white: Option[CorePlayerInfo],
+    black: Option[CorePlayerInfo],
+    timeControl: Option[CoreTimeControl],
+    mode: Option[String],
+)
+case class CoreGameResponse(gameId: String)
+
+@Path("/api/board/game")
+@RegisterRestClient(configKey = "core-service")
+@RegisterProvider(classOf[InternalSecretClientFilter])
+@RegisterClientHeaders(classOf[InternalClientHeadersFactory])
+trait CoreGameClient:
+
+  @POST
+  @Consumes(Array(MediaType.APPLICATION_JSON))
+  @Produces(Array(MediaType.APPLICATION_JSON))
+  def createGame(req: CoreCreateGameRequest): CoreGameResponse
@@ -0,0 +1,11 @@
+package de.nowchess.tournament.config
+
+import com.fasterxml.jackson.databind.ObjectMapper
+import com.fasterxml.jackson.module.scala.DefaultScalaModule
+import io.quarkus.jackson.ObjectMapperCustomizer
+import jakarta.inject.Singleton
+
+@Singleton
+class JacksonConfig extends ObjectMapperCustomizer:
+  def customize(objectMapper: ObjectMapper): Unit =
+    objectMapper.registerModule(DefaultScalaModule)
@@ -0,0 +1,12 @@
+package de.nowchess.tournament.config
+
+import jakarta.enterprise.context.ApplicationScoped
+import org.eclipse.microprofile.config.inject.ConfigProperty
+import scala.compiletime.uninitialized
+
+@ApplicationScoped
+class RedisConfig:
+  // scalafix:off DisableSyntax.var
+  @ConfigProperty(name = "nowchess.redis.prefix", defaultValue = "nowchess")
+  var prefix: String = uninitialized
+  // scalafix:on DisableSyntax.var
@@ -0,0 +1,33 @@
+package de.nowchess.tournament.domain
+
+import jakarta.persistence.*
+import scala.compiletime.uninitialized
+import java.time.Instant
+
+@Entity
+@Table(name = "tournaments")
+class Tournament:
+  // scalafix:off DisableSyntax.var
+  @Id
+  var id: String = uninitialized
+
+  @Column(nullable = false)
+  var fullName: String = uninitialized
+
+  var nbRounds: Int = 0
+  var clockLimit: Int = 0
+  var clockIncrement: Int = 0
+  var rated: Boolean = true
+
+  @Column(nullable = false)
+  var status: String = "created"
+
+  var currentRound: Int = 0
+
+  @Column(nullable = false)
+  var createdBy: String = uninitialized
+
+  var startsAt: Instant = uninitialized
+  var winnerId: String = uninitialized
+  var winnerName: String = uninitialized
+  // scalafix:on
@@ -0,0 +1,31 @@
+package de.nowchess.tournament.domain
+
+import jakarta.persistence.*
+import scala.compiletime.uninitialized
+import java.util.UUID
+
+@Entity
+@Table(name = "tournament_pairings")
+class TournamentPairing:
+  // scalafix:off DisableSyntax.var
+  @Id
+  @GeneratedValue(strategy = GenerationType.UUID)
+  var id: UUID = uninitialized
+
+  @Column(nullable = false)
+  var tournamentId: String = uninitialized
+
+  var round: Int = 0
+  var whiteId: String = uninitialized
+  var whiteName: String = uninitialized
+
+  @Column(nullable = false)
+  var blackId: String = uninitialized
+
+  @Column(nullable = false)
+  var blackName: String = uninitialized
+
+  var gameId: String = uninitialized
+  var winner: String = uninitialized
+  var moveList: String = uninitialized
+  // scalafix:on
@@ -0,0 +1,31 @@
+package de.nowchess.tournament.domain
+
+import jakarta.persistence.*
+import scala.compiletime.uninitialized
+import java.util.UUID
+
+@Entity
+@Table(name = "tournament_participants")
+class TournamentParticipant:
+  // scalafix:off DisableSyntax.var
+  @Id
+  @GeneratedValue(strategy = GenerationType.UUID)
+  var id: UUID = uninitialized
+
+  @Column(nullable = false)
+  var tournamentId: String = uninitialized
+
+  @Column(nullable = false)
+  var botId: String = uninitialized
+
+  @Column(nullable = false)
+  var botName: String = uninitialized
+
+  var points: Double = 0.0
+  var tieBreak: Double = 0.0
+  var nbGames: Int = 0
+  var wins: Int = 0
+  var draws: Int = 0
+  var losses: Int = 0
+  var byeCount: Int = 0
+  // scalafix:on
@@ -0,0 +1,74 @@
+package de.nowchess.tournament.dto
+
+case class BotRef(id: String, name: String)
+
+case class Clock(limit: Int, increment: Int)
+
+case class Variant(key: String, name: String)
+
+case class CreateTournamentForm(
+    name: String,
+    nbRounds: Int,
+    clockLimit: Int,
+    clockIncrement: Int,
+    rated: Boolean = true,
+)
+
+case class ResultDto(
+    rank: Int,
+    points: Double,
+    tieBreak: Double,
+    bot: BotRef,
+    nbGames: Int,
+    wins: Int,
+    draws: Int,
+    losses: Int,
+)
+
+case class Standing(page: Int, players: List[ResultDto])
+
+case class TournamentDto(
+    id: String,
+    fullName: String,
+    clock: Clock,
+    variant: Variant,
+    rated: Boolean,
+    nbPlayers: Int,
+    nbRounds: Int,
+    createdBy: String,
+    startsAt: Option[String],
+    status: String,
+    round: Int,
+    standing: Standing,
+    winner: Option[BotRef],
+)
+
+case class TournamentListDto(
+    created: List[TournamentDto],
+    started: List[TournamentDto],
+    finished: List[TournamentDto],
+)
+
+case class PairingDto(
+    id: String,
+    round: Int,
+    white: Option[BotRef],
+    black: BotRef,
+    gameId: Option[String],
+    winner: Option[String],
+)
+
+case class GameExportDto(
+    id: String,
+    round: Int,
+    white: BotRef,
+    black: BotRef,
+    winner: Option[String],
+    moves: String,
+)
+
+case class RoundPairingsDto(round: Int, pairings: List[PairingDto])
+
+case class ErrorDto(error: String)
+
+case class OkDto(ok: Boolean = true)
@@ -0,0 +1,10 @@
+package de.nowchess.tournament.error
+
+enum TournamentError(val message: String):
+  case NotFound(id: String)         extends TournamentError(s"Tournament $id not found")
+  case NotDirector                  extends TournamentError("Not the tournament director")
+  case WrongStatus(expected: String) extends TournamentError(s"Tournament must be in $expected status")
+  case AlreadyJoined                extends TournamentError("Already joined this tournament")
+  case NotJoined                    extends TournamentError("Not joined this tournament")
+  case NotEnoughParticipants        extends TournamentError("Need at least 2 participants to start")
+  case NotABot                      extends TournamentError("Only bot accounts can join tournaments")
@@ -0,0 +1,82 @@
+package de.nowchess.tournament.redis
+
+import com.fasterxml.jackson.databind.ObjectMapper
+import de.nowchess.api.dto.GameWritebackEventDto
+import de.nowchess.tournament.config.RedisConfig
+import de.nowchess.tournament.service.TournamentService
+import io.quarkus.redis.datasource.RedisDataSource
+import io.quarkus.redis.datasource.stream.{StreamMessage, XGroupCreateArgs, XReadGroupArgs}
+import io.quarkus.runtime.Startup
+import jakarta.annotation.PostConstruct
+import jakarta.enterprise.context.ApplicationScoped
+import jakarta.inject.Inject
+import org.eclipse.microprofile.context.ManagedExecutor
+import org.jboss.logging.Logger
+import scala.compiletime.uninitialized
+import scala.jdk.CollectionConverters.*
+import scala.util.{Failure, Success, Try}
+import java.util.UUID
+
+@Startup
+@ApplicationScoped
+class GameResultStreamListener:
+  // scalafix:off DisableSyntax.var
+  @Inject var redis: RedisDataSource                         = uninitialized
+  @Inject var objectMapper: ObjectMapper                     = uninitialized
+  @Inject var tournamentService: TournamentService           = uninitialized
+  @Inject var executor: ManagedExecutor                      = uninitialized
+  @Inject var redisConfig: RedisConfig                       = uninitialized
+  // scalafix:on
+
+  private val log        = Logger.getLogger(classOf[GameResultStreamListener])
+  private val groupName  = "tournament-result"
+  private val consumerId = UUID.randomUUID().toString
+
+  private def streamKey = s"${redisConfig.prefix}:game-writeback"
+
+  @PostConstruct
+  def startListening(): Unit =
+    createGroupIfAbsent()
+    executor.submit(new Runnable:
+      def run(): Unit = pollLoop()
+    )
+    log.infof("Tournament result listener started (consumer=%s)", consumerId)
+
+  private def createGroupIfAbsent(): Unit =
+    Try(redis.stream(classOf[String]).xgroupCreate(streamKey, groupName, "0", new XGroupCreateArgs().mkstream())) match
+      case Failure(ex) if Option(ex.getMessage).exists(_.contains("BUSYGROUP")) => ()
+      case Failure(ex) => log.warnf(ex, "Failed to create consumer group")
+      case Success(_)  => ()
+
+  private def pollLoop(): Unit =
+    while true do
+      Try {
+        val messages = redis.stream(classOf[String]).xreadgroup(
+          groupName,
+          consumerId,
+          streamKey,
+          ">",
+          new XReadGroupArgs().count(10).block(java.time.Duration.ofSeconds(2)),
+        )
+        if messages != null then messages.forEach(msg => handleMessage(msg))
+      } match
+        case Failure(ex) => log.warnf(ex, "Error in result poll loop")
+        case Success(_)  => ()
+
+  private def handleMessage(msg: StreamMessage[String, String, String]): Unit =
+    val json = msg.payload().get("data")
+    Try(objectMapper.readValue(json, classOf[GameWritebackEventDto])) match
+      case Failure(ex) =>
+        log.errorf(ex, "Unparseable game result event: %s", json)
+        ack(msg.id())
+      case Success(event) =>
+        if event.result.isDefined then
+          Try(tournamentService.handleGameResult(event.gameId, event.result.get, event.pgn)) match
+            case Failure(ex) => log.errorf(ex, "Failed to handle game result for %s", event.gameId)
+            case Success(_)  => ()
+        ack(msg.id())
+
+  private def ack(id: String): Unit =
+    Try(redis.stream(classOf[String]).xack(streamKey, groupName, id)) match
+      case Failure(ex) => log.warnf(ex, "Failed to ack message %s", id)
+      case Success(_)  => ()
@@ -0,0 +1,47 @@
+package de.nowchess.tournament.repository
+
+import de.nowchess.tournament.domain.TournamentPairing
+import jakarta.enterprise.context.ApplicationScoped
+import jakarta.inject.Inject
+import jakarta.persistence.EntityManager
+import scala.compiletime.uninitialized
+import scala.jdk.CollectionConverters.*
+import java.util.UUID
+
+@ApplicationScoped
+class PairingRepository:
+
+  @Inject
+  // scalafix:off DisableSyntax.var
+  var em: EntityManager = uninitialized
+  // scalafix:on
+
+  def findByTournamentId(tournamentId: String): List[TournamentPairing] =
+    em.createQuery("FROM TournamentPairing WHERE tournamentId = :tid", classOf[TournamentPairing])
+      .setParameter("tid", tournamentId)
+      .getResultList
+      .asScala
+      .toList
+
+  def findByTournamentIdAndRound(tournamentId: String, round: Int): List[TournamentPairing] =
+    em.createQuery(
+      "FROM TournamentPairing WHERE tournamentId = :tid AND round = :round",
+      classOf[TournamentPairing],
+    ).setParameter("tid", tournamentId)
+      .setParameter("round", round)
+      .getResultList
+      .asScala
+      .toList
+
+  def findByGameId(gameId: String): Option[TournamentPairing] =
+    em.createQuery("FROM TournamentPairing WHERE gameId = :gid", classOf[TournamentPairing])
+      .setParameter("gid", gameId)
+      .getResultList
+      .asScala
+      .headOption
+
+  def persist(p: TournamentPairing): TournamentPairing =
+    if p.id == null then
+      em.persist(p)
+      p
+    else em.merge(p)
@@ -0,0 +1,43 @@
+package de.nowchess.tournament.repository
+
+import de.nowchess.tournament.domain.TournamentParticipant
+import jakarta.enterprise.context.ApplicationScoped
+import jakarta.inject.Inject
+import jakarta.persistence.EntityManager
+import scala.compiletime.uninitialized
+import scala.jdk.CollectionConverters.*
+import java.util.UUID
+
+@ApplicationScoped
+class ParticipantRepository:
+
+  @Inject
+  // scalafix:off DisableSyntax.var
+  var em: EntityManager = uninitialized
+  // scalafix:on
+
+  def findByTournamentId(tournamentId: String): List[TournamentParticipant] =
+    em.createQuery("FROM TournamentParticipant WHERE tournamentId = :tid", classOf[TournamentParticipant])
+      .setParameter("tid", tournamentId)
+      .getResultList
+      .asScala
+      .toList
+
+  def findByTournamentIdAndBotId(tournamentId: String, botId: String): Option[TournamentParticipant] =
+    em.createQuery(
+      "FROM TournamentParticipant WHERE tournamentId = :tid AND botId = :bid",
+      classOf[TournamentParticipant],
+    ).setParameter("tid", tournamentId)
+      .setParameter("bid", botId)
+      .getResultList
+      .asScala
+      .headOption
+
+  def persist(p: TournamentParticipant): TournamentParticipant =
+    if p.id == null then
+      em.persist(p)
+      p
+    else em.merge(p)
+
+  def delete(p: TournamentParticipant): Unit =
+    em.remove(if em.contains(p) then p else em.merge(p))
@@ -0,0 +1,33 @@
+package de.nowchess.tournament.repository
+
+import de.nowchess.tournament.domain.Tournament
+import jakarta.enterprise.context.ApplicationScoped
+import jakarta.inject.Inject
+import jakarta.persistence.EntityManager
+import scala.compiletime.uninitialized
+import scala.jdk.CollectionConverters.*
+
+@ApplicationScoped
+class TournamentRepository:
+
+  @Inject
+  // scalafix:off DisableSyntax.var
+  var em: EntityManager = uninitialized
+  // scalafix:on
+
+  def findOptById(id: String): Option[Tournament] =
+    Option(em.find(classOf[Tournament], id))
+
+  def findByStatus(status: String): List[Tournament] =
+    em.createQuery("FROM Tournament WHERE status = :status", classOf[Tournament])
+      .setParameter("status", status)
+      .getResultList
+      .asScala
+      .toList
+
+  def persist(t: Tournament): Tournament =
+    if em.contains(t) then t else em.merge(t)
+
+  def delete(t: Tournament): Unit =
+    val managed = if em.contains(t) then t else em.merge(t)
+    em.remove(managed)
@@ -0,0 +1,184 @@
+package de.nowchess.tournament.resource
+
+import de.nowchess.tournament.dto.*
+import de.nowchess.tournament.error.TournamentError
+import de.nowchess.tournament.service.{TournamentService, TournamentStreamManager}
+import io.smallrye.mutiny.Multi
+import jakarta.annotation.security.{PermitAll, RolesAllowed}
+import jakarta.enterprise.context.ApplicationScoped
+import jakarta.inject.Inject
+import jakarta.ws.rs.*
+import jakarta.ws.rs.core.{Context, HttpHeaders, MediaType, Response}
+import org.eclipse.microprofile.jwt.JsonWebToken
+import org.jboss.logging.Logger
+import scala.compiletime.uninitialized
+
+@Path("/api/tournament")
+@ApplicationScoped
+@Produces(Array(MediaType.APPLICATION_JSON))
+@Consumes(Array(MediaType.APPLICATION_JSON))
+class TournamentResource:
+
+  private val log = Logger.getLogger(classOf[TournamentResource])
+
+  // scalafix:off DisableSyntax.var
+  @Inject var tournamentService: TournamentService   = uninitialized
+  @Inject var streamManager: TournamentStreamManager = uninitialized
+  @Inject var jwt: JsonWebToken                      = uninitialized
+  // scalafix:on
+
+  @GET
+  @PermitAll
+  def list(): Response =
+    val (created, started, finished) = tournamentService.list()
+    val dto = TournamentListDto(
+      created = created.map(t => tournamentService.toDto(t)),
+      started = started.map(t => tournamentService.toDto(t)),
+      finished = finished.map(t => tournamentService.toDto(t)),
+    )
+    Response.ok(dto).build()
+
+  @POST
+  @RolesAllowed(Array("**"))
+  @Consumes(Array(MediaType.APPLICATION_FORM_URLENCODED))
+  def create(
+      @FormParam("name") name: String,
+      @FormParam("nbRounds") nbRounds: Int,
+      @FormParam("clockLimit") clockLimit: Int,
+      @FormParam("clockIncrement") clockIncrement: Int,
+      @FormParam("rated") @DefaultValue("true") rated: Boolean,
+  ): Response =
+    val userId = Option(jwt.getSubject).getOrElse("")
+    val form   = CreateTournamentForm(name, nbRounds, clockLimit, clockIncrement, rated)
+    val t      = tournamentService.create(userId, form)
+    Response.status(Response.Status.CREATED).entity(tournamentService.toDto(t)).build()
+
+  @GET
+  @Path("/{id}")
+  @PermitAll
+  def get(@PathParam("id") id: String): Response =
+    tournamentService.get(id) match
+      case None => Response.status(Response.Status.NOT_FOUND).entity(ErrorDto(s"Tournament $id not found")).build()
+      case Some(t) =>
+        val standings = tournamentService.getStandings(id)
+        Response.ok(tournamentService.toDto(t, standings)).build()
+
+  @DELETE
+  @Path("/{id}")
+  @RolesAllowed(Array("**"))
+  def terminate(@PathParam("id") id: String): Response =
+    val userId = Option(jwt.getSubject).getOrElse("")
+    tournamentService.terminate(id, userId) match
+      case Right(_)    => Response.noContent().build()
+      case Left(error) => errorResponse(error)
+
+  @POST
+  @Path("/{id}/start")
+  @RolesAllowed(Array("**"))
+  def start(@PathParam("id") id: String): Response =
+    val userId = Option(jwt.getSubject).getOrElse("")
+    tournamentService.start(id, userId) match
+      case Right(t)    => Response.ok(tournamentService.toDto(t)).build()
+      case Left(error) => errorResponse(error)
+
+  @POST
+  @Path("/{id}/join")
+  @RolesAllowed(Array("**"))
+  def join(@PathParam("id") id: String): Response =
+    val tokenType = Option(jwt.getClaim[AnyRef]("type")).map(_.toString).getOrElse("")
+    if tokenType != "bot" then
+      Response.status(Response.Status.FORBIDDEN).entity(ErrorDto("Only bots can join tournaments")).build()
+    else
+      val botId   = Option(jwt.getSubject).getOrElse("")
+      val botName = Option(jwt.getClaim[AnyRef]("name")).map(_.toString).getOrElse(botId)
+      tournamentService.join(id, botId, botName) match
+        case Right(_)    => Response.ok(OkDto()).build()
+        case Left(error) => errorResponse(error)
+
+  @POST
+  @Path("/{id}/withdraw")
+  @RolesAllowed(Array("**"))
+  def withdraw(@PathParam("id") id: String): Response =
+    val tokenType = Option(jwt.getClaim[AnyRef]("type")).map(_.toString).getOrElse("")
+    if tokenType != "bot" then
+      Response.status(Response.Status.FORBIDDEN).entity(ErrorDto("Only bots can withdraw")).build()
+    else
+      val botId = Option(jwt.getSubject).getOrElse("")
+      tournamentService.withdraw(id, botId) match
+        case Right(_)    => Response.ok(OkDto()).build()
+        case Left(error) => errorResponse(error)
+
+  @GET
+  @Path("/{id}/results")
+  @Produces(Array("application/x-ndjson"))
+  @PermitAll
+  def results(
+      @PathParam("id") id: String,
+      @QueryParam("nb") @DefaultValue("100") nb: Int,
+  ): Response =
+    tournamentService.get(id) match
+      case None => Response.status(Response.Status.NOT_FOUND).entity("").build()
+      case Some(_) =>
+        val ndjson = tournamentService.getResults(id).take(nb).map { r =>
+          s"""{"rank":${r.rank},"points":${r.points},"tieBreak":${r.tieBreak},"bot":{"id":"${r.bot.id}","name":"${r.bot.name}"},"nbGames":${r.nbGames},"wins":${r.wins},"draws":${r.draws},"losses":${r.losses}}"""
+        }.mkString("\n")
+        Response.ok(ndjson).`type`("application/x-ndjson").build()
+
+  @GET
+  @Path("/{id}/round/{round}")
+  @PermitAll
+  def roundPairings(@PathParam("id") id: String, @PathParam("round") round: Int): Response =
+    tournamentService.get(id) match
+      case None => Response.status(Response.Status.NOT_FOUND).entity(ErrorDto(s"Tournament $id not found")).build()
+      case Some(_) =>
+        val pairings = tournamentService.getPairings(id, round)
+        Response.ok(RoundPairingsDto(round, pairings)).build()
+
+  @GET
+  @Path("/{id}/export/games")
+  @PermitAll
+  @Produces(Array(MediaType.APPLICATION_JSON, MediaType.WILDCARD, "application/x-ndjson", "application/x-chess-pgn"))
+  def exportGames(@PathParam("id") id: String, @Context headers: HttpHeaders): Response =
+    tournamentService.get(id) match
+      case None => Response.status(Response.Status.NOT_FOUND).entity(ErrorDto(s"Tournament $id not found")).build()
+      case Some(_) =>
+        val acceptHeader = Option(headers.getHeaderString("Accept")).getOrElse("")
+        val pairings     = tournamentService.getAllPairings(id)
+        if acceptHeader.contains("application/x-ndjson") then
+          val ndjson = pairings
+            .filter(p => Option(p.whiteId).isDefined && Option(p.gameId).isDefined)
+            .map { p =>
+              val winner = Option(p.winner).map(w => s""""$w"""").getOrElse("null")
+              val moves  = Option(p.moveList).getOrElse("")
+              s"""{"id":"${p.gameId}","round":${p.round},"white":{"id":"${p.whiteId}","name":"${p.whiteName}"},"black":{"id":"${p.blackId}","name":"${p.blackName}"},"winner":$winner,"moves":"$moves"}"""
+            }
+            .mkString("\n")
+          Response.ok(ndjson).`type`("application/x-ndjson").build()
+        else
+          val pgn = pairings.flatMap(p => Option(p.moveList)).mkString("\n\n")
+          Response.ok(pgn).`type`("application/x-chess-pgn").build()
+
+  @GET
+  @Path("/{id}/stream")
+  @RolesAllowed(Array("**"))
+  @Produces(Array("application/x-ndjson"))
+  def stream(@PathParam("id") id: String): Multi[String] =
+    tournamentService.get(id) match
+      case None => Multi.createFrom().failure(new NotFoundException(s"Tournament $id not found"))
+      case Some(_) =>
+        val botId = Option(jwt.getSubject).getOrElse("")
+        Multi.createFrom().emitter[String] { emitter =>
+          streamManager.register(id, botId, emitter)
+          emitter.onTermination(() => streamManager.unregister(id, botId, emitter))
+        }
+
+  private def errorResponse(error: TournamentError): Response =
+    val status = error match
+      case TournamentError.NotFound(_)           => Response.Status.NOT_FOUND
+      case TournamentError.NotDirector           => Response.Status.FORBIDDEN
+      case TournamentError.NotABot               => Response.Status.FORBIDDEN
+      case TournamentError.WrongStatus(_)        => Response.Status.CONFLICT
+      case TournamentError.AlreadyJoined         => Response.Status.CONFLICT
+      case TournamentError.NotJoined             => Response.Status.CONFLICT
+      case TournamentError.NotEnoughParticipants => Response.Status.CONFLICT
+    Response.status(status).entity(ErrorDto(error.message)).build()
@@ -0,0 +1,68 @@
+package de.nowchess.tournament.service
+
+import de.nowchess.tournament.domain.{TournamentParticipant, TournamentPairing}
+import java.util.concurrent.ThreadLocalRandom
+
+object SwissPairingService:
+
+  def computePairings(
+      participants: List[TournamentParticipant],
+      pastPairings: List[TournamentPairing],
+  ): (List[(TournamentParticipant, TournamentParticipant)], Option[TournamentParticipant]) =
+    val sorted = sortParticipants(participants)
+    val (remaining, byeOpt) = extractByePlayer(sorted)
+    val pairs = buildPairs(remaining, pastPairings)
+    (pairs, byeOpt)
+
+  private def sortParticipants(participants: List[TournamentParticipant]): List[TournamentParticipant] =
+    participants.sortWith { (a, b) =>
+      if a.points != b.points then a.points > b.points
+      else if a.tieBreak != b.tieBreak then a.tieBreak > b.tieBreak
+      else a.botName < b.botName
+    }
+
+  private def extractByePlayer(
+      sorted: List[TournamentParticipant],
+  ): (List[TournamentParticipant], Option[TournamentParticipant]) =
+    if sorted.size % 2 == 0 then (sorted, None)
+    else
+      val minByes  = sorted.map(_.byeCount).min
+      val byeIndex = sorted.lastIndexWhere(_.byeCount == minByes)
+      val bye      = sorted(byeIndex)
+      (sorted.filterNot(_ eq bye), Some(bye))
+
+  private def buildPairs(
+      players: List[TournamentParticipant],
+      pastPairings: List[TournamentPairing],
+  ): List[(TournamentParticipant, TournamentParticipant)] =
+    val arr = players.toArray
+    resolveConflicts(arr, pastPairings)
+    arr.grouped(2).flatMap {
+      case Array(a, b) => Some(assignColors(a, b))
+      case _           => None
+    }.toList
+
+  private def resolveConflicts(arr: Array[TournamentParticipant], pastPairings: List[TournamentPairing]): Unit =
+    var i = 0
+    while i < arr.length - 1 do
+      if havePlayedBefore(arr(i), arr(i + 1), pastPairings) && i + 2 < arr.length then
+        val tmp    = arr(i + 1)
+        arr(i + 1) = arr(i + 2)
+        arr(i + 2) = tmp
+      i += 2
+
+  private def havePlayedBefore(
+      a: TournamentParticipant,
+      b: TournamentParticipant,
+      pastPairings: List[TournamentPairing],
+  ): Boolean =
+    pastPairings.exists(p =>
+      (p.whiteId == a.botId && p.blackId == b.botId) ||
+        (p.whiteId == b.botId && p.blackId == a.botId),
+    )
+
+  private def assignColors(
+      a: TournamentParticipant,
+      b: TournamentParticipant,
+  ): (TournamentParticipant, TournamentParticipant) =
+    if ThreadLocalRandom.current().nextBoolean() then (a, b) else (b, a)
@@ -0,0 +1,284 @@
+package de.nowchess.tournament.service
+
+import de.nowchess.tournament.client.{CoreCreateGameRequest, CoreGameClient, CorePlayerInfo, CoreTimeControl}
+import de.nowchess.tournament.domain.{Tournament, TournamentPairing, TournamentParticipant}
+import de.nowchess.tournament.dto.{BotRef, Clock, CreateTournamentForm, PairingDto, ResultDto, Standing, TournamentDto, Variant}
+import de.nowchess.tournament.error.TournamentError
+import de.nowchess.tournament.repository.{PairingRepository, ParticipantRepository, TournamentRepository}
+import jakarta.enterprise.context.ApplicationScoped
+import jakarta.inject.Inject
+import jakarta.transaction.Transactional
+import org.eclipse.microprofile.rest.client.inject.RestClient
+import org.jboss.logging.Logger
+import scala.compiletime.uninitialized
+import scala.util.{Failure, Success, Try}
+import java.time.Instant
+
+@ApplicationScoped
+class TournamentService:
+
+  private val log = Logger.getLogger(classOf[TournamentService])
+
+  // scalafix:off DisableSyntax.var
+  @Inject var tournamentRepository: TournamentRepository   = uninitialized
+  @Inject var participantRepository: ParticipantRepository = uninitialized
+  @Inject var pairingRepository: PairingRepository         = uninitialized
+  @Inject var streamManager: TournamentStreamManager       = uninitialized
+
+  @Inject
+  @RestClient
+  var coreGameClient: CoreGameClient = uninitialized
+  // scalafix:on
+
+  @Transactional
+  def create(createdBy: String, form: CreateTournamentForm): Tournament =
+    val t = new Tournament()
+    t.id = scala.util.Random.alphanumeric.take(6).mkString
+    t.fullName = form.name
+    t.nbRounds = form.nbRounds
+    t.clockLimit = form.clockLimit
+    t.clockIncrement = form.clockIncrement
+    t.rated = form.rated
+    t.status = "created"
+    t.currentRound = 0
+    t.createdBy = createdBy
+    tournamentRepository.persist(t)
+    t
+
+  def get(id: String): Option[Tournament] =
+    tournamentRepository.findOptById(id)
+
+  def list(): (List[Tournament], List[Tournament], List[Tournament]) =
+    (
+      tournamentRepository.findByStatus("created"),
+      tournamentRepository.findByStatus("started"),
+      tournamentRepository.findByStatus("finished"),
+    )
+
+  @Transactional
+  def terminate(id: String, userId: String): Either[TournamentError, Unit] =
+    for
+      t <- tournamentRepository.findOptById(id).toRight(TournamentError.NotFound(id))
+      _ <- Either.cond(t.createdBy == userId, (), TournamentError.NotDirector)
+      _ <- Either.cond(t.status == "created", (), TournamentError.WrongStatus("created"))
+    yield
+      tournamentRepository.delete(t)
+
+  @Transactional
+  def join(id: String, botId: String, botName: String): Either[TournamentError, Unit] =
+    for
+      t <- tournamentRepository.findOptById(id).toRight(TournamentError.NotFound(id))
+      _ <- Either.cond(t.status == "created", (), TournamentError.WrongStatus("created"))
+      _ <- Either.cond(
+        participantRepository.findByTournamentIdAndBotId(id, botId).isEmpty,
+        (),
+        TournamentError.AlreadyJoined,
+      )
+    yield
+      val p = new TournamentParticipant()
+      p.tournamentId = id
+      p.botId = botId
+      p.botName = botName
+      participantRepository.persist(p)
+
+  @Transactional
+  def withdraw(id: String, botId: String): Either[TournamentError, Unit] =
+    for
+      t <- tournamentRepository.findOptById(id).toRight(TournamentError.NotFound(id))
+      _ <- Either.cond(t.status == "created", (), TournamentError.WrongStatus("created"))
+      p <- participantRepository.findByTournamentIdAndBotId(id, botId).toRight(TournamentError.NotJoined)
+    yield participantRepository.delete(p)
+
+  @Transactional
+  def start(id: String, userId: String): Either[TournamentError, Tournament] =
+    for
+      t            <- tournamentRepository.findOptById(id).toRight(TournamentError.NotFound(id))
+      _            <- Either.cond(t.createdBy == userId, (), TournamentError.NotDirector)
+      _            <- Either.cond(t.status == "created", (), TournamentError.WrongStatus("created"))
+      participants <- validateMinParticipants(id)
+    yield
+      t.status = "started"
+      t.currentRound = 1
+      t.startsAt = Instant.now()
+      tournamentRepository.persist(t)
+      streamManager.publish(t.id, """{"type":"tournamentStarted"}""")
+      startRound(t, 1, participants)
+      t
+
+  private def validateMinParticipants(id: String): Either[TournamentError, List[TournamentParticipant]] =
+    val ps = participantRepository.findByTournamentId(id)
+    Either.cond(ps.size >= 2, ps, TournamentError.NotEnoughParticipants)
+
+  private def startRound(t: Tournament, round: Int, participants: List[TournamentParticipant]): Unit =
+    val pastPairings = pairingRepository.findByTournamentId(t.id)
+    val (pairs, byeOpt) = SwissPairingService.computePairings(participants, pastPairings)
+    byeOpt.foreach(bye => createByePairing(t.id, round, bye))
+    pairs.foreach { case (white, black) => createRealPairing(t.id, round, white, black, t) }
+    streamManager.publish(t.id, s"""{"type":"roundStarted","round":$round}""")
+
+  private def createByePairing(tournamentId: String, round: Int, bye: TournamentParticipant): Unit =
+    val pairing = new TournamentPairing()
+    pairing.tournamentId = tournamentId
+    pairing.round = round
+    pairing.blackId = bye.botId
+    pairing.blackName = bye.botName
+    pairing.winner = "bye"
+    pairingRepository.persist(pairing)
+    bye.points += 0.5
+    bye.byeCount += 1
+    participantRepository.persist(bye)
+
+  private def createRealPairing(
+      tournamentId: String,
+      round: Int,
+      white: TournamentParticipant,
+      black: TournamentParticipant,
+      t: Tournament,
+  ): Unit =
+    val tc = CoreTimeControl(Some(t.clockLimit), Some(t.clockIncrement), None)
+    val req = CoreCreateGameRequest(
+      Some(CorePlayerInfo(white.botId, white.botName)),
+      Some(CorePlayerInfo(black.botId, black.botName)),
+      Some(tc),
+      if t.rated then Some("Rated") else Some("Casual"),
+    )
+    Try(coreGameClient.createGame(req)) match
+      case Failure(ex) => log.errorf(ex, "Failed to create game for round %d in tournament %s", round, tournamentId)
+      case Success(resp) =>
+        val pairing = new TournamentPairing()
+        pairing.tournamentId = tournamentId
+        pairing.round = round
+        pairing.whiteId = white.botId
+        pairing.whiteName = white.botName
+        pairing.blackId = black.botId
+        pairing.blackName = black.botName
+        pairing.gameId = resp.gameId
+        pairingRepository.persist(pairing)
+        streamManager.publishToBot(tournamentId, white.botId, s"""{"type":"gameStart","round":$round,"gameId":"${resp.gameId}","color":"white"}""")
+        streamManager.publishToBot(tournamentId, black.botId, s"""{"type":"gameStart","round":$round,"gameId":"${resp.gameId}","color":"black"}""")
+
+  @Transactional
+  def handleGameResult(gameId: String, result: String, pgn: String): Unit =
+    pairingRepository.findByGameId(gameId).foreach { pairing =>
+      val (winnerStr, wPts, bPts) = parseResult(result)
+      pairing.winner = winnerStr
+      pairing.moveList = pgn
+      pairingRepository.persist(pairing)
+      updateParticipantStats(pairing, wPts, bPts)
+      checkRoundCompletion(pairing.tournamentId)
+    }
+
+  private def parseResult(result: String): (String, Double, Double) = result match
+    case "1-0"     => ("white", 1.0, 0.0)
+    case "0-1"     => ("black", 0.0, 1.0)
+    case "1/2-1/2" => ("draw", 0.5, 0.5)
+    case _         => ("draw", 0.5, 0.5)
+
+  private def updateParticipantStats(pairing: TournamentPairing, wPts: Double, bPts: Double): Unit =
+    Option(pairing.whiteId).foreach { wId =>
+      participantRepository.findByTournamentIdAndBotId(pairing.tournamentId, wId).foreach { p =>
+        p.points += wPts
+        p.nbGames += 1
+        if wPts == 1.0 then p.wins += 1 else if wPts == 0.5 then p.draws += 1 else p.losses += 1
+        participantRepository.persist(p)
+      }
+    }
+    participantRepository.findByTournamentIdAndBotId(pairing.tournamentId, pairing.blackId).foreach { p =>
+      p.points += bPts
+      p.nbGames += 1
+      if bPts == 1.0 then p.wins += 1 else if bPts == 0.5 then p.draws += 1 else p.losses += 1
+      participantRepository.persist(p)
+    }
+
+  private def checkRoundCompletion(tournamentId: String): Unit =
+    tournamentRepository.findOptById(tournamentId).foreach { t =>
+      val roundPairings = pairingRepository.findByTournamentIdAndRound(tournamentId, t.currentRound)
+      val allDone = roundPairings.nonEmpty && roundPairings.forall(p => Option(p.winner).isDefined)
+      if allDone then onRoundComplete(t)
+    }
+
+  private def onRoundComplete(t: Tournament): Unit =
+    streamManager.publish(t.id, s"""{"type":"roundFinished","round":${t.currentRound}}""")
+    recomputeBuchholz(t.id)
+    if t.currentRound >= t.nbRounds then finishTournament(t)
+    else
+      t.currentRound += 1
+      tournamentRepository.persist(t)
+      val participants = participantRepository.findByTournamentId(t.id)
+      startRound(t, t.currentRound, participants)
+
+  private def finishTournament(t: Tournament): Unit =
+    val participants = sortedStandings(participantRepository.findByTournamentId(t.id))
+    participants.headOption.foreach { winner =>
+      t.winnerId = winner.botId
+      t.winnerName = winner.botName
+    }
+    t.status = "finished"
+    tournamentRepository.persist(t)
+    val winnerInfo = participants.headOption
+      .map(w => s"""{"id":"${w.botId}","name":"${w.botName}"}""")
+      .getOrElse("null")
+    streamManager.publish(t.id, s"""{"type":"tournamentFinished","winner":$winnerInfo}""")
+
+  private def recomputeBuchholz(tournamentId: String): Unit =
+    val participants = participantRepository.findByTournamentId(tournamentId)
+    val pairings     = pairingRepository.findByTournamentId(tournamentId)
+    val pointsById   = participants.map(p => p.botId -> p.points).toMap
+    participants.foreach { p =>
+      val opponentIds = pairings.flatMap(pair =>
+        if pair.whiteId == p.botId then Some(pair.blackId)
+        else if pair.blackId == p.botId && Option(pair.whiteId).isDefined then Some(pair.whiteId)
+        else None,
+      )
+      p.tieBreak = opponentIds.flatMap(id => pointsById.get(id)).sum
+      participantRepository.persist(p)
+    }
+
+  def getStandings(tournamentId: String): List[ResultDto] =
+    val participants = sortedStandings(participantRepository.findByTournamentId(tournamentId))
+    participants.zipWithIndex.map { case (p, idx) =>
+      ResultDto(idx + 1, p.points, p.tieBreak, BotRef(p.botId, p.botName), p.nbGames, p.wins, p.draws, p.losses)
+    }
+
+  def getPairings(tournamentId: String, round: Int): List[PairingDto] =
+    pairingRepository.findByTournamentIdAndRound(tournamentId, round).map(toPairingDto)
+
+  def getAllPairings(tournamentId: String): List[TournamentPairing] =
+    pairingRepository.findByTournamentId(tournamentId)
+
+  def getResults(tournamentId: String): List[ResultDto] = getStandings(tournamentId)
+
+  def toDto(t: Tournament, standings: List[ResultDto] = Nil): TournamentDto =
+    val participants = participantRepository.findByTournamentId(t.id)
+    TournamentDto(
+      id = t.id,
+      fullName = t.fullName,
+      clock = Clock(t.clockLimit, t.clockIncrement),
+      variant = Variant("standard", "Standard"),
+      rated = t.rated,
+      nbPlayers = participants.size,
+      nbRounds = t.nbRounds,
+      createdBy = t.createdBy,
+      startsAt = Option(t.startsAt).map(_.toString),
+      status = t.status,
+      round = t.currentRound,
+      standing = Standing(1, standings),
+      winner = if t.winnerId != null then Some(BotRef(t.winnerId, t.winnerName)) else None,
+    )
+
+  private def toPairingDto(p: TournamentPairing): PairingDto =
+    PairingDto(
+      id = p.id.toString,
+      round = p.round,
+      white = Option(p.whiteId).map(id => BotRef(id, p.whiteName)),
+      black = BotRef(p.blackId, p.blackName),
+      gameId = Option(p.gameId),
+      winner = Option(p.winner),
+    )
+
+  private def sortedStandings(participants: List[TournamentParticipant]): List[TournamentParticipant] =
+    participants.sortWith { (a, b) =>
+      if a.points != b.points then a.points > b.points
+      else if a.tieBreak != b.tieBreak then a.tieBreak > b.tieBreak
+      else a.botName < b.botName
+    }
@@ -0,0 +1,32 @@
+package de.nowchess.tournament.service
+
+import io.smallrye.mutiny.subscription.MultiEmitter
+import jakarta.enterprise.context.ApplicationScoped
+import java.util.concurrent.{ConcurrentHashMap, CopyOnWriteArrayList}
+import scala.jdk.CollectionConverters.*
+
+@ApplicationScoped
+class TournamentStreamManager:
+
+  private val tournamentEmitters = new ConcurrentHashMap[String, CopyOnWriteArrayList[MultiEmitter[? >: String]]]()
+  private val botEmitters        = new ConcurrentHashMap[String, CopyOnWriteArrayList[MultiEmitter[? >: String]]]()
+
+  private def botKey(tournamentId: String, botId: String): String = s"${tournamentId}:${botId}"
+
+  def register(tournamentId: String, botId: String, emitter: MultiEmitter[? >: String]): Unit =
+    tournamentEmitters.computeIfAbsent(tournamentId, _ => new CopyOnWriteArrayList[MultiEmitter[? >: String]]()).add(emitter)
+    botEmitters.computeIfAbsent(botKey(tournamentId, botId), _ => new CopyOnWriteArrayList[MultiEmitter[? >: String]]()).add(emitter)
+
+  def unregister(tournamentId: String, botId: String, emitter: MultiEmitter[? >: String]): Unit =
+    Option(tournamentEmitters.get(tournamentId)).foreach(_.remove(emitter))
+    Option(botEmitters.get(botKey(tournamentId, botId))).foreach(_.remove(emitter))
+
+  def publish(tournamentId: String, eventJson: String): Unit =
+    Option(tournamentEmitters.get(tournamentId)).foreach { list =>
+      list.asScala.foreach(e => scala.util.Try(e.emit(eventJson)))
+    }
+
+  def publishToBot(tournamentId: String, botId: String, eventJson: String): Unit =
+    Option(botEmitters.get(botKey(tournamentId, botId))).foreach { list =>
+      list.asScala.foreach(e => scala.util.Try(e.emit(eventJson)))
+    }