[Server] Stop mirroring is_tournament on the game-state event

The client learns tournament status from Event_GameJoined's ServerInfo_Game;
mirroring it on every Event_GameStateChanged was dead wire data. The field was
removed from the proto in [Protocol]; drop the now-invalidated setter.

libcockatrice_network/libcockatrice/network/server/remote/CMakeLists.txt

@@ -14,9 +14,12 @@ set(HEADERS
     game/server_deck_validation_strategy.h
     game/server_game.h
     game/server_game_lifecycle_strategy.h
-    game/server_match_result_strategy.h
     game/server_match_game_factory.h
+    game/server_match_result_strategy.h
     game/server_player.h
+    game/server_tournament.h
+    game/server_tournament_lifecycle_strategy.h
+    game/server_tournament_match_result_strategy.h
     game/server_spectator.h
     server.h
     server_abstractuserinterface.h
@@ -43,6 +46,9 @@ add_library(
   game/server_game.cpp
   game/server_player.cpp
   game/server_spectator.cpp
+  game/server_tournament.cpp
+  game/server_tournament_lifecycle_strategy.cpp
+  game/server_tournament_match_result_strategy.cpp
   server.cpp
   server_abstractuserinterface.cpp
   server_database_interface.cpp

libcockatrice_network/libcockatrice/network/server/remote/game/server_abstract_participant.cpp

@@ -41,6 +41,7 @@
 #include <libcockatrice/protocol/pb/command_set_sideboard_lock.pb.h>
 #include <libcockatrice/protocol/pb/command_set_sideboard_plan.pb.h>
 #include <libcockatrice/protocol/pb/command_shuffle.pb.h>
+#include <libcockatrice/protocol/pb/command_tournament.pb.h>
 #include <libcockatrice/protocol/pb/command_undo_draw.pb.h>
 #include <libcockatrice/protocol/pb/context_connection_state_changed.pb.h>
 #include <libcockatrice/protocol/pb/event_game_say.pb.h>
@@ -536,6 +537,15 @@ Server_AbstractParticipant::processGameCommand(const GameCommand &command, Respo
         case GameCommand::SET_PLAYMAT:
             return cmdSetPlaymat(command.GetExtension(Command_SetPlaymat::ext), rc, ges);
             break;
+        case GameCommand::REPORT_MATCH_RESULT:
+            return cmdReportMatchResult(command.GetExtension(Command_ReportMatchResult::ext), rc, ges);
+            break;
+        case GameCommand::ADVANCE_TOURNAMENT:
+            return cmdAdvanceTournament(command.GetExtension(Command_AdvanceTournament::ext), rc, ges);
+            break;
+        case GameCommand::TOURNAMENT_SETTINGS_SELECT:
+            return cmdTournamentSettingsSelect(command.GetExtension(Command_TournamentSettingsSelect::ext), rc, ges);
+            break;
         default:
             return Response::RespInvalidCommand;
     }
@@ -570,7 +580,7 @@ void Server_AbstractParticipant::setUserInterface(Server_AbstractUserInterface *
 void Server_AbstractParticipant::disconnectClient()
 {
     bool isRegistered = userInfo->user_level() & ServerInfo_User::IsRegistered;
-    if (!isRegistered || spectator) {
+    if (!isRegistered || spectator || game->getDisconnectRemovesPlayer()) {
         game->removeParticipant(this, Event_Leave::USER_DISCONNECTED);
     } else {
         setUserInterface(nullptr);
@@ -584,3 +594,25 @@ void Server_AbstractParticipant::getInfo(ServerInfo_Player *info,
 {
     getProperties(*info->mutable_properties(), withUserInfo);
 }
+
+Response::ResponseCode Server_AbstractParticipant::cmdReportMatchResult(const Command_ReportMatchResult & /*cmd*/,
+                                                                        ResponseContainer & /*rc*/,
+                                                                        GameEventStorage & /*ges*/)
+{
+    return Response::RespContextError;
+}
+
+Response::ResponseCode Server_AbstractParticipant::cmdAdvanceTournament(const Command_AdvanceTournament & /*cmd*/,
+                                                                        ResponseContainer & /*rc*/,
+                                                                        GameEventStorage & /*ges*/)
+{
+    return Response::RespContextError;
+}
+
+Response::ResponseCode
+Server_AbstractParticipant::cmdTournamentSettingsSelect(const Command_TournamentSettingsSelect & /*cmd*/,
+                                                        ResponseContainer & /*rc*/,
+                                                        GameEventStorage & /*ges*/)
+{
+    return Response::RespContextError;
+}

libcockatrice_network/libcockatrice/network/server/remote/game/server_abstract_participant.h

@@ -53,6 +53,9 @@ class Command_DeckSelect;
 class Command_SetSideboardLock;
 class Command_ChangeZoneProperties;
 class Command_SetPlaymat;
+class Command_ReportMatchResult;
+class Command_AdvanceTournament;
+class Command_TournamentSettingsSelect;
 
 class Server_AbstractParticipant : public Server_ArrowTarget, public ServerInfo_User_Container
 {
@@ -175,6 +178,13 @@ public:
     cmdReverseTurn(const Command_ReverseTurn & /*cmd*/, ResponseContainer & /*rc*/, GameEventStorage &ges);
     virtual Response::ResponseCode
     cmdChangeZoneProperties(const Command_ChangeZoneProperties &cmd, ResponseContainer &rc, GameEventStorage &ges);
+    virtual Response::ResponseCode
+    cmdReportMatchResult(const Command_ReportMatchResult &cmd, ResponseContainer &rc, GameEventStorage &ges);
+    virtual Response::ResponseCode
+    cmdAdvanceTournament(const Command_AdvanceTournament &cmd, ResponseContainer &rc, GameEventStorage &ges);
+    virtual Response::ResponseCode cmdTournamentSettingsSelect(const Command_TournamentSettingsSelect &cmd,
+                                                               ResponseContainer &rc,
+                                                               GameEventStorage &ges);
 
     Response::ResponseCode processGameCommand(const GameCommand &command, ResponseContainer &rc, GameEventStorage &ges);
     void sendGameEvent(const GameEventContainer &event);

libcockatrice_network/libcockatrice/network/server/remote/game/server_abstract_player.cpp

@@ -1663,3 +1663,9 @@ void Server_AbstractPlayer::getPlayerProperties(ServerInfo_PlayerProperties &res
         playmatParams->set_zoom(playmat.params.zoom);
     }
 }
+
+void Server_AbstractPlayer::setDeck(DeckList *_deck)
+{
+    delete deck;
+    deck = _deck;
+}

libcockatrice_network/libcockatrice/network/server/remote/game/server_abstract_player.h

@@ -47,6 +47,7 @@ public:
     {
         return deck;
     }
+    void setDeck(DeckList *_deck);
     bool getReadyStart() const
     {
         return readyStart;

libcockatrice_network/libcockatrice/network/server/remote/game/server_game.cpp

@@ -30,10 +30,14 @@
 #include "server_cardzone.h"
 #include "server_player.h"
 #include "server_spectator.h"
+#include "server_tournament.h"
+#include "server_tournament_lifecycle_strategy.h"
+#include "server_tournament_match_result_strategy.h"
 
 #include <QDebug>
 #include <QRegularExpression>
 #include <QTimer>
+#include <algorithm>
 #include <google/protobuf/descriptor.h>
 #include <libcockatrice/deck_list/deck_list.h>
 #include <libcockatrice/protocol/pb/context_connection_state_changed.pb.h>
@@ -62,8 +66,9 @@ Server_Game::Server_Game(const GameConfig &config, Server_Room *_room)
       spectatorsCanTalk(config.spectatorsCanTalk), spectatorsSeeEverything(config.spectatorsSeeEverything),
       startingLifeTotal(config.startingLifeTotal), shareDecklistsOnLoad(config.shareDecklistsOnLoad),
       inactivityCounter(0), startTimeOfThisGame(0), secondsElapsed(0), firstGameStarted(false),
-      turnOrderReversed(false), startTime(QDateTime::currentDateTime()), pingClock(nullptr),
-      deckValidationStrategy(new Server_DefaultDeckValidationStrategy),
+      turnOrderReversed(false), startTime(QDateTime::currentDateTime()), pingClock(nullptr), isTournament(false),
+      tournament(nullptr), tournamentParentGame(nullptr), tournamentMatchPlayer1Id(-1), tournamentMatchPlayer2Id(-1),
+      disconnectRemovesPlayer(false), deckValidationStrategy(new Server_DefaultDeckValidationStrategy),
       lifecycleStrategy(new Server_DefaultLifecycleStrategy), matchResultStrategy(new Server_NullMatchResultStrategy),
       gameMutex()
 {
@@ -265,6 +270,10 @@ void Server_Game::createGameStateChangedEvent(Event_GameStateChanged *event,
         event->set_game_started(false);
     }
 
+    if (tournamentParentGame) {
+        event->set_parent_game_id(tournamentParentGame->getGameId());
+    }
+
     for (Server_AbstractParticipant *participant : participants.values()) {
         participant->getInfo(event->add_player_list(), recipient, omniscient, withUserInfo);
     }
@@ -313,7 +322,14 @@ void Server_Game::doStartGameIfReady(bool forceStartGame)
     Server_DatabaseInterface *databaseInterface = room->getServer()->getDatabaseInterface();
     QMutexLocker locker(&gameMutex);
 
-    if (getPlayerCount() < maxPlayers && !forceStartGame) {
+    if (!isTournament && getPlayerCount() < maxPlayers && !forceStartGame) {
+        return;
+    }
+
+    // Tournament hubs must be host-started and can't lock in a partially filled
+    // bracket: a mere "everyone current is ready" must not start a 1-player or
+    // undersized tournament. startTournament() additionally enforces 2+ players.
+    if (isTournament && !forceStartGame) {
         return;
     }
 
@@ -567,6 +583,17 @@ void Server_Game::removeParticipant(Server_AbstractParticipant *participant, Eve
     bool playerHost = hostId == participant->getPlayerId();
     participant->prepareDestroy();
 
+    // If this is the tournament hub (not one of its match sub-games), never re-pair
+    // the leaving player: mark them dropped so their matches are awarded and they
+    // disappear from the bracket instead of stalling the tournament.
+    if (tournament && !tournamentParentGame && !spectator) {
+        const int leavingPlayerId = participant->getPlayerId();
+        GameEventStorage tournGes;
+        tournament->dropPlayer(leavingPlayerId);
+        tournament->broadcastTournamentState(tournGes);
+        tournGes.sendToGame(this);
+    }
+
     if (playerHost) {
         int newHostId = -1;
         for (auto *otherPlayer : getPlayers().values()) {
@@ -783,6 +810,15 @@ void Server_Game::createGameJoinedEvent(Server_AbstractParticipant *joiningParti
     }
 
     rc.enqueuePostResponseItem(ServerMessage::GAME_EVENT_CONTAINER, prepareGameEvent(event2, -1));
+
+    // A tournament's bracket/phase/standings live in Event_TournamentState, which
+    // normally only flows on mutation. Without a copy here a late joiner would sit
+    // on an empty bracket until the next round advances, so replay the current
+    // state as part of the join snapshot.
+    if (tournament) {
+        rc.enqueuePostResponseItem(ServerMessage::GAME_EVENT_CONTAINER,
+                                   prepareGameEvent(tournament->buildStateEvent(), -1));
+    }
 }
 
 void Server_Game::sendGameEventContainer(GameEventContainer *cont,
@@ -861,6 +897,7 @@ void Server_Game::getInfo(ServerInfo_Game &result) const
         result.set_share_decklists_on_load(shareDecklistsOnLoad);
         result.set_spectators_count(getSpectatorCount());
         result.set_start_time(startTime.toSecsSinceEpoch());
+        result.set_is_tournament(isTournament);
     }
 }
 
@@ -911,3 +948,92 @@ void Server_Game::setDeckValidationStrategy(Server_DeckValidationStrategy *strat
 {
     deckValidationStrategy.reset(strategy);
 }
+
+void Server_Game::setMatchResultStrategy(Server_MatchResultStrategy *strategy)
+{
+    matchResultStrategy.reset(strategy);
+}
+
+void Server_Game::setIsTournamentGame(bool _isTournament)
+{
+    isTournament = _isTournament;
+    if (isTournament) {
+        tournament = new Server_Tournament(this, this, this);
+        lifecycleStrategy.reset(new Server_TournamentLifecycleStrategy);
+        matchResultStrategy.reset(new Server_TournamentMatchResultStrategy);
+    } else if (tournament) {
+        delete tournament;
+        tournament = nullptr;
+        lifecycleStrategy.reset(new Server_DefaultLifecycleStrategy);
+        matchResultStrategy.reset(new Server_NullMatchResultStrategy);
+    }
+}
+
+void Server_Game::startTournament()
+{
+    if (!tournament) {
+        tournament = new Server_Tournament(this, this, this);
+    }
+
+    if (!tournament->isStarted()) {
+        // Add all current players to the tournament
+        auto players = getPlayers();
+        for (auto *player : players.values()) {
+            tournament->addPlayer(player->getPlayerId(), QString::fromStdString(player->getUserInfo()->name()));
+        }
+
+        // A tournament with fewer than two players can't produce a valid bracket.
+        if (tournament->getPlayerCount() < 2) {
+            qWarning() << "Cannot start tournament with fewer than 2 players";
+            return;
+        }
+
+        tournament->startTournament();
+    }
+
+    GameEventStorage ges;
+    tournament->broadcastTournamentState(ges);
+    ges.sendToGame(this);
+}
+
+void Server_Game::setPlayerTournamentDeck(int playerId, DeckList *deck)
+{
+    if (tournament) {
+        tournament->setPlayerDeck(playerId, deck);
+    }
+}
+
+void Server_Game::setTournamentMatchInfo(Server_Game *parentGame, int p1Id, int p2Id)
+{
+    tournamentParentGame = parentGame;
+    tournamentMatchPlayer1Id = p1Id;
+    tournamentMatchPlayer2Id = p2Id;
+}
+
+Server_Game *Server_Game::createMatchGame(const GameConfig &config, int &outGameId)
+{
+    Server_DatabaseInterface *databaseInterface = room->getServer()->getDatabaseInterface();
+    outGameId = databaseInterface->getNextGameId();
+    if (outGameId == -1) {
+        return nullptr;
+    }
+
+    GameConfig matchConfig = config;
+    matchConfig.gameId = outGameId;
+    auto *game = new Server_Game(matchConfig, room);
+    // Sub-games carry the tournament flag (for protocol fields) but keep the default
+    // strategies; the parent tournament drives them through the match result strategy
+    // installed by Server_Tournament::createMatchGame.
+    game->isTournament = true;
+    return game;
+}
+
+Server_AbstractUserInterface *Server_Game::getUserInterface(const QString &playerName)
+{
+    return room->getUserInterfaceByName(playerName);
+}
+
+void Server_Game::addGameToRoom(Server_Game *game)
+{
+    room->addGame(game);
+}

libcockatrice_network/libcockatrice/network/server/remote/game/server_game.h

@@ -24,31 +24,38 @@
 #include "game_config.h"
 #include "server_deck_validation_strategy.h"
 #include "server_game_lifecycle_strategy.h"
+#include "server_match_game_factory.h"
 #include "server_match_result_strategy.h"
 
 #include <QDateTime>
 #include <QMap>
 #include <QMutex>
 #include <QObject>
+#include <QPointer>
 #include <QScopedPointer>
 #include <QSet>
 #include <QStringList>
 #include <libcockatrice/protocol/pb/event_leave.pb.h>
+#include <libcockatrice/protocol/pb/event_tournament_state.pb.h>
 #include <libcockatrice/protocol/pb/response.pb.h>
 #include <libcockatrice/protocol/pb/serverinfo_game.pb.h>
 
 class QTimer;
+class DeckList;
 class GameEventContainer;
+class GameEventStorage;
 class GameReplay;
 class Server_Room;
 class Server_AbstractPlayer;
 class Server_AbstractParticipant;
+class Server_Card;
+class Server_Tournament;
 class ServerInfo_User;
 class ServerInfo_Game;
 class Server_AbstractUserInterface;
 class Event_GameStateChanged;
 
-class Server_Game : public QObject
+class Server_Game : public QObject, public Server_MatchGameFactory
 {
     Q_OBJECT
 private:
@@ -83,6 +90,14 @@ private:
     QList<GameReplay *> replayList;
     GameReplay *currentReplay;
 
+    bool isTournament;
+    TournamentSettings tournamentSettings;
+    Server_Tournament *tournament;
+    QPointer<Server_Game> tournamentParentGame;
+    int tournamentMatchPlayer1Id;
+    int tournamentMatchPlayer2Id;
+    bool disconnectRemovesPlayer;
+
     QScopedPointer<Server_DeckValidationStrategy> deckValidationStrategy;
 
     QScopedPointer<Server_GameLifecycleStrategy> lifecycleStrategy;
@@ -220,6 +235,49 @@ public:
     void returnCardsFromPlayer(GameEventStorage &ges, Server_AbstractPlayer *player);
 
     /** @brief Get the current deck validation strategy (non-owning). */
+    bool getIsTournamentGame() const
+    {
+        return isTournament;
+    }
+    void setIsTournamentGame(bool _isTournament);
+    bool getIsTournament() const
+    {
+        return tournament != nullptr;
+    }
+    Server_Tournament *getTournament() const
+    {
+        return tournament;
+    }
+    void startTournament();
+    void setPlayerTournamentDeck(int playerId, DeckList *deck);
+    void setTournamentMatchInfo(Server_Game *parentGame, int p1Id, int p2Id);
+    QPointer<Server_Game> getTournamentParentGame() const
+    {
+        return tournamentParentGame;
+    }
+    bool getDisconnectRemovesPlayer() const
+    {
+        return disconnectRemovesPlayer;
+    }
+    void setDisconnectRemovesPlayer(bool _disconnectRemovesPlayer)
+    {
+        disconnectRemovesPlayer = _disconnectRemovesPlayer;
+    }
+
+    // Server_MatchGameFactory implementation
+    Server_Game *createMatchGame(const GameConfig &config, int &outGameId) override;
+    Server_AbstractUserInterface *getUserInterface(const QString &playerName) override;
+    void addGameToRoom(Server_Game *game) override;
+
+    const TournamentSettings &getTournamentSettings() const
+    {
+        return tournamentSettings;
+    }
+    void setTournamentSettings(const TournamentSettings &settings)
+    {
+        tournamentSettings = settings;
+    }
+
     Server_DeckValidationStrategy *getDeckValidationStrategy() const
     {
         return deckValidationStrategy.data();
@@ -232,6 +290,8 @@ public:
     {
         return lifecycleStrategy.data();
     }
+    /** @brief Replace the match result strategy; takes ownership of @p strategy. */
+    void setMatchResultStrategy(Server_MatchResultStrategy *strategy);
 };
 
 #endif

libcockatrice_network/libcockatrice/network/server/remote/game/server_tournament.cpp

@@ -0,0 +1,691 @@
+#include "server_tournament.h"
+
+#include "../server_abstractuserinterface.h"
+#include "../server_response_containers.h"
+#include "../serverinfo_user_container.h"
+#include "game_config.h"
+#include "server_abstract_player.h"
+#include "server_game.h"
+#include "server_match_game_factory.h"
+#include "server_player.h"
+#include "server_tournament_match_result_strategy.h"
+
+#include <QLoggingCategory>
+#include <algorithm>
+#include <libcockatrice/deck_list/deck_list.h>
+#include <libcockatrice/protocol/pb/event_tournament_state.pb.h>
+#include <libcockatrice/protocol/pb/game_event_container.pb.h>
+
+inline Q_LOGGING_CATEGORY(TournamentLog, "tournament");
+
+Server_Tournament::Server_Tournament(Server_Game *_parentGame, Server_MatchGameFactory *_factory, QObject *parent)
+    : QObject(parent), parentGame(_parentGame), matchGameFactory(_factory), currentRound(0), totalRounds(0),
+      started(false)
+{
+}
+
+Server_Tournament::~Server_Tournament()
+{
+    qDeleteAll(submittedDecks);
+}
+
+void Server_Tournament::addPlayer(int playerId, const QString &playerName)
+{
+    QMutexLocker locker(&tournamentMutex);
+    TournamentPlayerData data;
+    data.playerId = playerId;
+    data.playerName = playerName;
+    data.dropped = false;
+    players[playerId] = data;
+}
+
+void Server_Tournament::setPlayerDeck(int playerId, DeckList *deck)
+{
+    QMutexLocker locker(&tournamentMutex);
+    delete submittedDecks.value(playerId, nullptr);
+    submittedDecks[playerId] = deck;
+    if (players.contains(playerId)) {
+        players[playerId].deckSubmitted = true;
+    }
+}
+
+void Server_Tournament::removePlayer(int playerId)
+{
+    QMutexLocker locker(&tournamentMutex);
+    players.remove(playerId);
+    submittedDecks.remove(playerId);
+    byeGivenPlayers.remove(playerId);
+}
+
+void Server_Tournament::dropPlayer(int playerId)
+{
+    QMutexLocker locker(&tournamentMutex);
+    if (!players.contains(playerId)) {
+        return;
+    }
+    players[playerId].dropped = true;
+    players[playerId].deckSubmitted = false;
+
+    // Any current pairing that involves the dropped player and is not already
+    // decided is awarded to the surviving opponent (or recorded as undecided if
+    // both dropped). The opponent keeps playing without sitting out a round.
+    for (auto &pairing : currentPairings) {
+        if (pairing.winnerId != -2) {
+            continue;
+        }
+        bool involvesDropped = (pairing.player1Id == playerId || pairing.player2Id == playerId);
+        if (!involvesDropped) {
+            continue;
+        }
+        if (pairing.player1Id == playerId && pairing.player2Id == playerId) {
+            continue;
+        }
+        int opponent = (pairing.player1Id == playerId) ? pairing.player2Id : pairing.player1Id;
+        if (players.contains(opponent) && !players[opponent].dropped) {
+            pairing.winnerId = opponent;
+            players[opponent].wins += 1;
+            players[playerId].losses += 1;
+        }
+        allPreviousPairings.append(qMakePair(pairing.player1Id, pairing.player2Id));
+    }
+}
+
+void Server_Tournament::startTournament()
+{
+    {
+        QMutexLocker locker(&tournamentMutex);
+        if (started) {
+            return;
+        }
+        totalRounds = calculateTotalRounds();
+        started = true;
+        currentRound = 0;
+        generateSwissPairings();
+    }
+
+    // Spawn the first round's match games
+    enqueueMatchGameCreation();
+}
+
+bool Server_Tournament::isAllDecksSubmitted() const
+{
+    QMutexLocker locker(&tournamentMutex);
+    for (auto it = players.constBegin(); it != players.constEnd(); ++it) {
+        if (!it->deckSubmitted) {
+            return false;
+        }
+    }
+    return true;
+}
+
+int Server_Tournament::getTournamentPlayerIdByName(const QString &name) const
+{
+    QMutexLocker locker(&tournamentMutex);
+    for (auto it = players.constBegin(); it != players.constEnd(); ++it) {
+        if (it->playerName == name) {
+            return it->playerId;
+        }
+    }
+    return -1;
+}
+
+void Server_Tournament::generateSwissPairings()
+{
+    currentPairings.clear();
+    QList<int> available;
+    for (auto it = players.constBegin(); it != players.constEnd(); ++it) {
+        if (!it->dropped) {
+            available.append(it->playerId);
+        }
+    }
+
+    // Sort by wins descending (and by record for tie-breaking)
+    std::sort(available.begin(), available.end(), [this](int a, int b) {
+        const auto &pa = players[a];
+        const auto &pb = players[b];
+        if (pa.wins != pb.wins) {
+            return pa.wins > pb.wins;
+        }
+        if (pa.losses != pb.losses) {
+            return pa.losses < pb.losses;
+        }
+        return a < b;
+    });
+
+    QSet<int> paired;
+    // Try to pair every player, allowing a single rematch only if the greedy pass
+    // would otherwise leave any unpaired remainder. Dropped players are never paired.
+    int maxRematches = available.size() / 2;
+    for (int i = 0; i < available.size(); ++i) {
+        if (paired.contains(available[i])) {
+            continue;
+        }
+        for (int j = i + 1; j < available.size(); ++j) {
+            if (paired.contains(available[j])) {
+                continue;
+            }
+            bool rematch = havePlayed(available[i], available[j]);
+            if (rematch && maxRematches <= 0) {
+                continue;
+            }
+            TournamentPairingData pairing;
+            pairing.player1Id = available[i];
+            pairing.player2Id = available[j];
+            currentPairings.append(pairing);
+            paired.insert(available[i]);
+            paired.insert(available[j]);
+            if (rematch) {
+                --maxRematches;
+            }
+            break;
+        }
+    }
+
+    // Give a bye to every remaining unpaired eligible player, worst-ranked first.
+    // A player receives at most one bye over the whole tournament.
+    QList<int> unpaired;
+    for (int id : available) {
+        if (!paired.contains(id)) {
+            unpaired.append(id);
+        }
+    }
+    // Byes go to the lowest-ranked eligible player who has not had one yet.
+    std::sort(unpaired.begin(), unpaired.end(), [this](int a, int b) {
+        const auto &pa = players[a];
+        const auto &pb = players[b];
+        if (pa.wins != pb.wins) {
+            return pa.wins < pb.wins;
+        }
+        if (pa.losses != pb.losses) {
+            return pa.losses > pb.losses;
+        }
+        return a > b;
+    });
+
+    for (int id : unpaired) {
+        if (byeGivenPlayers.contains(id)) {
+            // Already used a bye: a dropped opponent or earlier bye means this player
+            // simply sits out the round with a free win to keep the bracket moving.
+            TournamentPairingData bye;
+            bye.player1Id = id;
+            bye.player2Id = -1;
+            bye.winnerId = id;
+            currentPairings.append(bye);
+            continue;
+        }
+        TournamentPairingData bye;
+        bye.player1Id = id;
+        bye.player2Id = -1;
+        bye.winnerId = id;
+        currentPairings.append(bye);
+        players[id].wins += 1;
+        byeGivenPlayers.insert(id);
+        allPreviousPairings.append(qMakePair(id, -1));
+    }
+}
+
+int Server_Tournament::calculateTotalRounds() const
+{
+    int n = 0;
+    for (auto it = players.constBegin(); it != players.constEnd(); ++it) {
+        if (!it->dropped) {
+            ++n;
+        }
+    }
+    if (n <= 1) {
+        return 0;
+    }
+    // Standard Swiss rounds: ceil(log2(n))
+    int rounds = 0;
+    while ((1 << rounds) < n) {
+        ++rounds;
+    }
+    return rounds;
+}
+
+bool Server_Tournament::havePlayed(int p1, int p2) const
+{
+    for (const auto &pair : allPreviousPairings) {
+        if ((pair.first == p1 && pair.second == p2) || (pair.first == p2 && pair.second == p1)) {
+            return true;
+        }
+    }
+    return false;
+}
+
+void Server_Tournament::advanceRound(GameEventStorage &ges)
+{
+    {
+        QMutexLocker locker(&tournamentMutex);
+        ++currentRound;
+        if (currentRound >= totalRounds) {
+            broadcastTournamentState(ges);
+            return;
+        }
+        generateSwissPairings();
+    }
+
+    enqueueMatchGameCreation();
+    broadcastTournamentState(ges);
+}
+
+bool Server_Tournament::allPairingsDecided() const
+{
+    for (const auto &pairing : currentPairings) {
+        if (pairing.winnerId == -2) {
+            return false;
+        }
+    }
+    return true;
+}
+
+void Server_Tournament::enqueueMatchGameCreation()
+{
+    QList<QPair<int, int>> planned;
+    {
+        QMutexLocker locker(&tournamentMutex);
+        for (const auto &pairing : currentPairings) {
+            if (pairing.player2Id == -1 || pairing.winnerId != -2) {
+                continue;
+            }
+            if (players.value(pairing.player1Id).dropped || players.value(pairing.player2Id).dropped) {
+                continue;
+            }
+            if (pairing.matchGameIds.size() >= static_cast<int>(gamesPerMatch)) {
+                continue;
+            }
+            planned.append(qMakePair(pairing.player1Id, pairing.player2Id));
+        }
+    }
+    if (planned.isEmpty()) {
+        return;
+    }
+
+    // Create the games from the event loop instead of the caller's stack: command
+    // processing holds game mutexes, and room registration takes gamesLock, so spawning
+    // synchronously would nest lock orders. The queued job runs once this object's
+    // owning thread returns to its event loop with no locks held; it is dropped if this
+    // tournament is destroyed first.
+    QMetaObject::invokeMethod(
+        this,
+        [this, planned] {
+            for (const auto &pair : planned) {
+                createMatchGame(pair.first, pair.second);
+            }
+
+            GameEventStorage ges;
+            broadcastTournamentState(ges);
+            ges.sendToGame(parentGame);
+        },
+        Qt::QueuedConnection);
+}
+
+void Server_Tournament::createMatchGame(int player1Id, int player2Id)
+{
+    if (!matchGameFactory || player2Id == -1) {
+        return;
+    }
+
+    QString player1Name;
+    QString player2Name;
+    QString deck1Native;
+    QString deck2Native;
+    int round = 0;
+    int gameNumber = 1;
+    {
+        QMutexLocker locker(&tournamentMutex);
+        player1Name = players.value(player1Id).playerName;
+        player2Name = players.value(player2Id).playerName;
+
+        if (submittedDecks.contains(player1Id)) {
+            deck1Native = submittedDecks.value(player1Id)->writeToString_Native();
+        }
+        if (submittedDecks.contains(player2Id)) {
+            deck2Native = submittedDecks.value(player2Id)->writeToString_Native();
+        }
+
+        round = currentRound;
+        for (const auto &pairing : currentPairings) {
+            if (pairing.player1Id == player1Id && pairing.player2Id == player2Id) {
+                gameNumber = pairing.matchGameIds.size() + 1;
+                break;
+            }
+        }
+
+        // Defense in depth: never exceed the configured series length
+        for (const auto &pairing : currentPairings) {
+            if (pairing.player1Id == player1Id && pairing.player2Id == player2Id &&
+                pairing.matchGameIds.size() >= static_cast<int>(gamesPerMatch)) {
+                qCWarning(TournamentLog) << "Refusing to exceed series length for pairing" << player1Id << player2Id;
+                return;
+            }
+        }
+
+        // Bail out if either participant is no longer connected: a match game with
+        // zero or one connected player can never finish and would stall the round.
+        if (!matchGameFactory->getUserInterface(player1Name) || !matchGameFactory->getUserInterface(player2Name)) {
+            qCWarning(TournamentLog) << "Skipping match creation: a player in pairing" << player1Id << player2Id
+                                     << "is no longer connected";
+            return;
+        }
+    }
+
+    // Create a sub-game for this match via the factory, copying the real
+    // ServerInfo_User so it ships the true user level rather than a fabricated
+    // admin identity that would surface in buddy/ignore-list checks.
+    ServerInfo_User creatorInfo;
+    if (auto *ui = matchGameFactory->getUserInterface(player1Name)) {
+        creatorInfo = *ui->getUserInfo();
+    } else {
+        creatorInfo.set_name(player1Name.toStdString());
+    }
+
+    QString gameDesc = gamesPerMatch > 1
+                           ? QString("R%1 Match - Game %2 of %3").arg(round).arg(gameNumber).arg(gamesPerMatch)
+                           : QString("Tournament Round %1").arg(round);
+
+    GameConfig matchConfig;
+    matchConfig.creatorInfo = creatorInfo;
+    matchConfig.description = gameDesc;
+    matchConfig.maxPlayers = 2;
+    matchConfig.startingLifeTotal = parentGame->getStartingLifeTotal();
+
+    int matchGameId = -1;
+    auto *matchGame = matchGameFactory->createMatchGame(matchConfig, matchGameId);
+    if (!matchGame || matchGameId == -1) {
+        return;
+    }
+
+    matchGame->setTournamentMatchInfo(parentGame, player1Id, player2Id);
+    matchGame->setMatchResultStrategy(new Server_TournamentMatchResultStrategy);
+    // A disconnect inside a tournament match must remove the player so the match
+    // can be decided; it must not leave them sitting as a half-present participant.
+    matchGame->setDisconnectRemovesPlayer(true);
+    matchGameFactory->addGameToRoom(matchGame);
+
+    // Store the game ID in the pairing
+    {
+        QMutexLocker locker(&tournamentMutex);
+        for (auto &pairing : currentPairings) {
+            if (pairing.player1Id == player1Id && pairing.player2Id == player2Id) {
+                pairing.gameId = matchGameId;
+                pairing.matchGameIds.append(matchGameId);
+                break;
+            }
+        }
+    }
+
+    // Auto-join both players, sending the join event directly through their UIs.
+    // Both UI lookups were verified above, so a player can only drop between that
+    // check and this add — in which case they get handled by drop processing and
+    // the pairing settles on the surviving opponent.
+    QMap<int, QPair<Server_AbstractUserInterface *, ResponseContainer *>> joiners;
+
+    auto joinAndSetupPlayer = [&](int pid, const QString &name) {
+        Server_AbstractUserInterface *ui = matchGameFactory->getUserInterface(name);
+        if (ui) {
+            auto *rc = new ResponseContainer(0);
+            matchGame->addPlayer(ui, *rc, false, false, false);
+            joiners[pid] = qMakePair(ui, rc);
+        }
+    };
+
+    joinAndSetupPlayer(player1Id, player1Name);
+    joinAndSetupPlayer(player2Id, player2Name);
+
+    // Now send the enqueued GameJoined + GameStateChanged events to each player's client.
+    for (auto it = joiners.constBegin(); it != joiners.constEnd(); ++it) {
+        it.value().first->sendResponseContainer(*it.value().second, Response::RespNothing);
+        delete it.value().second;
+    }
+    joiners.clear();
+
+    // Set decks and mark players as ready in the match game.
+    bool anyDeckMissing = false;
+    auto matchPlayers = matchGame->getPlayers();
+    for (auto *matchPlayer : matchPlayers) {
+        const QString name = QString::fromStdString(matchPlayer->getUserInfo()->name());
+        QString deckNative;
+        if (name == player1Name) {
+            deckNative = deck1Native;
+        } else if (name == player2Name) {
+            deckNative = deck2Native;
+        }
+
+        if (!deckNative.isEmpty()) {
+            matchPlayer->setDeck(new DeckList(deckNative));
+            matchPlayer->setReadyStart(true);
+        } else {
+            anyDeckMissing = true;
+        }
+    }
+
+    if (anyDeckMissing) {
+        // Not every participant submitted a deck. Do not force-start: that would
+        // kick the players without a deck. Leave the match game open so they can
+        // select a deck; the host starts it through the normal ready flow.
+        return;
+    }
+
+    // Start the match game without forcing: both participants are ready and have
+    // decks, so there is nothing to kick.
+    matchGame->startGameIfReady(false);
+}
+
+void Server_Tournament::recordMatchResult(int playerId1, int playerId2, int winnerId, GameEventStorage &ges)
+{
+    QMutexLocker locker(&tournamentMutex);
+
+    // Find the pairing and set the winner
+    for (auto &pairing : currentPairings) {
+        if ((pairing.player1Id == playerId1 && pairing.player2Id == playerId2) ||
+            (pairing.player1Id == playerId2 && pairing.player2Id == playerId1)) {
+            if (pairing.winnerId != -2) {
+                return; // Already recorded — defense in depth against double-call
+            }
+            pairing.winnerId = winnerId;
+            break;
+        }
+    }
+
+    // Update player records
+    if (winnerId == -1) {
+        // Draw
+        players[playerId1].draws += 1;
+        players[playerId2].draws += 1;
+    } else if (winnerId == playerId1) {
+        players[playerId1].wins += 1;
+        players[playerId2].losses += 1;
+    } else if (winnerId == playerId2) {
+        players[playerId2].wins += 1;
+        players[playerId1].losses += 1;
+    }
+
+    // Store for future pairing avoidance
+    allPreviousPairings.append(qMakePair(playerId1, playerId2));
+
+    // Check if all pairings in current round have results
+    bool allDecided = true;
+    for (const auto &pairing : currentPairings) {
+        if (pairing.winnerId == -2) {
+            allDecided = false;
+            break;
+        }
+    }
+
+    broadcastTournamentState(ges);
+
+    if (allDecided) {
+        advanceRound(ges);
+    }
+}
+
+bool Server_Tournament::recordMatchResultByGameId(int gameId, int winnerId, GameEventStorage &ges)
+{
+    bool matchDecided = false;
+    bool seriesContinues = false;
+    int p1 = -1;
+    int p2 = -1;
+    {
+        QMutexLocker locker(&tournamentMutex);
+
+        // Find the pairing that owns this game
+        TournamentPairingData *pairingPtr = nullptr;
+        for (auto &pairing : currentPairings) {
+            if (pairing.matchGameIds.contains(gameId)) {
+                pairingPtr = &pairing;
+                break;
+            }
+        }
+
+        if (!pairingPtr) {
+            return false;
+        }
+
+        // If the match is already decided, ignore further sub-game results
+        if (pairingPtr->winnerId != -2) {
+            return true;
+        }
+
+        // Increment per-match wins
+        if (winnerId == pairingPtr->player1Id) {
+            pairingPtr->player1MatchWins += 1;
+        } else if (winnerId == pairingPtr->player2Id) {
+            pairingPtr->player2MatchWins += 1;
+        }
+        // Draw (winnerId == -1): counts nothing toward the series but does consume
+        // a slot, so a series can still end in a draw when it is exhausted.
+
+        // The winner needs a strict majority of the games in the series.
+        const int gamesPlayed = pairingPtr->matchGameIds.size();
+        const int gamesNeeded = static_cast<int>(gamesPerMatch / 2 + 1);
+        const int gamesRemaining = static_cast<int>(gamesPerMatch) - gamesPlayed;
+        matchDecided = (pairingPtr->player1MatchWins >= gamesNeeded) || (pairingPtr->player2MatchWins >= gamesNeeded);
+        if (!matchDecided) {
+            // Series exhausted without a strict-majority winner (e.g. a drawn Bo3
+            // leaves it 1-1): record the match as a draw so the round always advances.
+            matchDecided = (gamesRemaining <= 0) && (pairingPtr->player1MatchWins == pairingPtr->player2MatchWins);
+        }
+
+        if (matchDecided) {
+            // Determine match winner
+            int matchWinnerId = -1;
+            if (pairingPtr->player1MatchWins >= gamesNeeded) {
+                matchWinnerId = pairingPtr->player1Id;
+            } else if (pairingPtr->player2MatchWins >= gamesNeeded) {
+                matchWinnerId = pairingPtr->player2Id;
+            }
+            // Otherwise the series was exhausted evenly — matchWinnerId stays -1 (a draw).
+
+            // Set the match winner on the pairing
+            pairingPtr->winnerId = matchWinnerId;
+
+            // Update tournament-level player records
+            if (matchWinnerId == pairingPtr->player1Id) {
+                players[pairingPtr->player1Id].wins += 1;
+                players[pairingPtr->player2Id].losses += 1;
+            } else if (matchWinnerId == pairingPtr->player2Id) {
+                players[pairingPtr->player2Id].wins += 1;
+                players[pairingPtr->player1Id].losses += 1;
+            } else {
+                players[pairingPtr->player1Id].draws += 1;
+                players[pairingPtr->player2Id].draws += 1;
+            }
+
+            // Store for future pairing avoidance
+            allPreviousPairings.append(qMakePair(pairingPtr->player1Id, pairingPtr->player2Id));
+        } else {
+            // Match not decided — spawn the next sub-game outside all locks
+            seriesContinues = true;
+            p1 = pairingPtr->player1Id;
+            p2 = pairingPtr->player2Id;
+        }
+
+        broadcastTournamentState(ges);
+    }
+
+    if (seriesContinues) {
+        QMetaObject::invokeMethod(
+            this,
+            [this, p1, p2] {
+                createMatchGame(p1, p2);
+
+                GameEventStorage nextGes;
+                broadcastTournamentState(nextGes);
+                nextGes.sendToGame(parentGame);
+            },
+            Qt::QueuedConnection);
+    }
+
+    checkAndAdvanceRound(ges);
+
+    return matchDecided;
+}
+
+void Server_Tournament::checkAndAdvanceRound(GameEventStorage &ges)
+{
+    bool roundComplete = false;
+    {
+        QMutexLocker locker(&tournamentMutex);
+        roundComplete = allPairingsDecided();
+    }
+
+    if (roundComplete) {
+        advanceRound(ges);
+    }
+}
+
+Event_TournamentState Server_Tournament::buildStateEvent() const
+{
+    QMutexLocker locker(&tournamentMutex);
+
+    Event_TournamentState state;
+
+    if (started && currentRound >= totalRounds) {
+        state.set_phase(Event_TournamentState::PHASE_FINISHED);
+    } else if (started) {
+        state.set_phase(Event_TournamentState::PHASE_PLAYING);
+    } else {
+        state.set_phase(Event_TournamentState::PHASE_DECK_BUILDING);
+    }
+
+    state.set_current_round(currentRound);
+    state.set_total_rounds(totalRounds);
+
+    // Settings
+    TournamentSettings *settings = state.mutable_settings();
+    settings->set_games_per_match(gamesPerMatch);
+
+    for (auto it = players.constBegin(); it != players.constEnd(); ++it) {
+        TournamentPlayer *p = state.add_players();
+        p->set_player_id(it->playerId);
+        p->set_player_name(it->playerName.toStdString());
+        p->set_wins(it->wins);
+        p->set_losses(it->losses);
+        p->set_draws(it->draws);
+        p->set_deck_submitted(it->deckSubmitted);
+    }
+
+    for (const auto &pairing : currentPairings) {
+        TournamentPairing *p = state.add_pairings();
+        p->set_player1_id(pairing.player1Id);
+        p->set_player2_id(pairing.player2Id);
+        p->set_game_id(pairing.gameId);
+        // -2 = undecided; a decided draw is -1. The is_draw bit distinguishes a
+        // reported draw from an unset winner_id on the wire.
+        if (pairing.winnerId == -1) {
+            p->set_is_draw(true);
+        } else if (pairing.winnerId != -2) {
+            p->set_winner_id(pairing.winnerId);
+        }
+        p->set_player1_match_wins(pairing.player1MatchWins);
+        p->set_player2_match_wins(pairing.player2MatchWins);
+    }
+
+    return state;
+}
+
+void Server_Tournament::broadcastTournamentState(GameEventStorage &ges)
+{
+    ges.enqueueGameEvent(buildStateEvent(), -1);
+}

libcockatrice_network/libcockatrice/network/server/remote/game/server_tournament.h

@@ -0,0 +1,116 @@
+#ifndef SERVER_TOURNAMENT_H
+#define SERVER_TOURNAMENT_H
+
+#include <QList>
+#include <QMap>
+#include <QObject>
+#include <QPointer>
+#include <QRecursiveMutex>
+#include <QSet>
+#include <libcockatrice/protocol/pb/event_tournament_state.pb.h>
+
+class DeckList;
+class Server_Game;
+class Server_MatchGameFactory;
+class Server_AbstractParticipant;
+class Server_AbstractUserInterface;
+class GameEventStorage;
+
+/** @brief Maximum number of games per match a tournament can be configured with. */
+constexpr int MAX_GAMES_PER_MATCH = 5;
+
+class Server_Tournament : public QObject
+{
+    Q_OBJECT
+public:
+    explicit Server_Tournament(Server_Game *_parentGame, Server_MatchGameFactory *_factory, QObject *parent = nullptr);
+    ~Server_Tournament() override;
+
+    void addPlayer(int playerId, const QString &playerName);
+    void removePlayer(int playerId);
+    // Marks an already-starting/started tournament player as dropped: they stop
+    // being paired and their outstanding unstarted match is awarded as a loss.
+    void dropPlayer(int playerId);
+    void startTournament();
+    void advanceRound(GameEventStorage &ges);
+    void recordMatchResult(int playerId1, int playerId2, int winnerId, GameEventStorage &ges);
+    bool recordMatchResultByGameId(int gameId, int winnerId, GameEventStorage &ges);
+    void broadcastTournamentState(GameEventStorage &ges);
+    // Current tournament state message, for replaying to a participant joining late.
+    Event_TournamentState buildStateEvent() const;
+
+    bool isStarted() const
+    {
+        return started;
+    }
+    bool isAllDecksSubmitted() const;
+    int getPlayerCount() const
+    {
+        return players.size();
+    }
+    int getTournamentPlayerIdByName(const QString &name) const;
+    void setPlayerDeckSubmitted(int playerId)
+    {
+        if (players.contains(playerId)) {
+            players[playerId].deckSubmitted = true;
+        }
+    }
+    void setPlayerDeck(int playerId, DeckList *deck);
+
+    void setGamesPerMatch(uint32_t n)
+    {
+        gamesPerMatch = n;
+    }
+    uint32_t getGamesPerMatch() const
+    {
+        return gamesPerMatch;
+    }
+
+    struct TournamentPlayerData
+    {
+        int playerId;
+        QString playerName;
+        int wins = 0;
+        int losses = 0;
+        int draws = 0;
+        bool deckSubmitted = false;
+        bool dropped = false;
+    };
+
+    struct TournamentPairingData
+    {
+        int player1Id;
+        int player2Id;
+        int gameId = -1;
+        int winnerId = -2; // -2 = undecided, -1 = draw, >= 0 = winner player id
+        int player1MatchWins = 0;
+        int player2MatchWins = 0;
+        QList<int> matchGameIds;
+    };
+
+private:
+    QPointer<Server_Game> parentGame;
+    Server_MatchGameFactory *matchGameFactory;
+    mutable QRecursiveMutex tournamentMutex;
+    QMap<int, TournamentPlayerData> players;
+    QMap<int, DeckList *> submittedDecks;
+    QList<TournamentPairingData> currentPairings;
+    // Players that have already received a bye in a previous round, so no one
+    // gets more than one bye over the whole tournament.
+    QSet<int> byeGivenPlayers;
+    QList<QPair<int, int>> allPreviousPairings;
+    int currentRound;
+    int totalRounds;
+    bool started;
+    uint32_t gamesPerMatch = 1;
+
+    void generateSwissPairings();
+    int calculateTotalRounds() const;
+    bool havePlayed(int p1, int p2) const;
+    bool allPairingsDecided() const;
+    void createMatchGame(int player1Id, int player2Id);
+    void enqueueMatchGameCreation();
+    void checkAndAdvanceRound(GameEventStorage &ges);
+};
+
+#endif // SERVER_TOURNAMENT_H

libcockatrice_network/libcockatrice/network/server/remote/game/server_tournament_lifecycle_strategy.cpp

@@ -0,0 +1,33 @@
+#include "server_tournament_lifecycle_strategy.h"
+
+#include "server_abstract_player.h"
+#include "server_game.h"
+
+#include <QLoggingCategory>
+
+inline Q_LOGGING_CATEGORY(TournamentLifecycleLog, "tournament_lifecycle");
+
+Server_GameLifecycleStrategy::StartAction Server_TournamentLifecycleStrategy::onGameStarting(Server_Game *game)
+{
+    // Match sub-games start through the normal flow; only the tournament hub game is
+    // managed by this lifecycle.
+    if (game->getTournamentParentGame().data() != nullptr) {
+        return StartAction::ProceedNormal;
+    }
+
+    for (auto *player : game->getPlayers().values()) {
+        if (!player->getDeckList()) {
+            qCWarning(TournamentLifecycleLog)
+                << "Tournament cannot start: player" << player->getUserInfo()->name().c_str() << "has no deck";
+            return StartAction::Handled;
+        }
+    }
+
+    if (!game->getIsTournamentGame()) {
+        qCWarning(TournamentLifecycleLog) << "Tournament lifecycle used for non-tournament game — falling back";
+        return StartAction::ProceedNormal;
+    }
+
+    game->startTournament();
+    return StartAction::Handled;
+}

libcockatrice_network/libcockatrice/network/server/remote/game/server_tournament_lifecycle_strategy.h

@@ -0,0 +1,12 @@
+#ifndef SERVER_TOURNAMENT_LIFECYCLE_STRATEGY_H
+#define SERVER_TOURNAMENT_LIFECYCLE_STRATEGY_H
+
+#include "server_game_lifecycle_strategy.h"
+
+class Server_TournamentLifecycleStrategy : public Server_GameLifecycleStrategy
+{
+public:
+    StartAction onGameStarting(Server_Game *game) override;
+};
+
+#endif

libcockatrice_network/libcockatrice/network/server/remote/game/server_tournament_match_result_strategy.cpp

@@ -0,0 +1,37 @@
+#include "server_tournament_match_result_strategy.h"
+
+#include "../server_response_containers.h"
+#include "server_abstract_player.h"
+#include "server_game.h"
+#include "server_tournament.h"
+
+#include <libcockatrice/protocol/pb/event_game_closed.pb.h>
+#include <libcockatrice/protocol/pb/event_tournament_state.pb.h>
+
+bool Server_TournamentMatchResultStrategy::onGameFinished(Server_Game *game,
+                                                          int playing,
+                                                          Server_AbstractPlayer *lastPlayer)
+{
+    // The hub game is owned by the room and may be torn down once its host leaves
+    // and no players remain, while the match sub-games keep running. QPointer keeps
+    // this link checked so a later-finishing match can't touch freed memory.
+    auto *parentGame = game->getTournamentParentGame().data();
+    if (!parentGame || !parentGame->getTournament()) {
+        return false;
+    }
+
+    int winnerId;
+    if (playing == 0) {
+        winnerId = -1;
+    } else {
+        QString winnerName = QString::fromStdString(lastPlayer->getUserInfo()->name());
+        auto *tournament = parentGame->getTournament();
+        winnerId = tournament->getTournamentPlayerIdByName(winnerName);
+    }
+
+    GameEventStorage parentGes;
+    bool matchDecided = parentGame->getTournament()->recordMatchResultByGameId(game->getGameId(), winnerId, parentGes);
+    parentGes.sendToGame(parentGame);
+
+    return matchDecided;
+}

libcockatrice_network/libcockatrice/network/server/remote/game/server_tournament_match_result_strategy.h

@@ -0,0 +1,12 @@
+#ifndef SERVER_TOURNAMENT_MATCH_RESULT_STRATEGY_H
+#define SERVER_TOURNAMENT_MATCH_RESULT_STRATEGY_H
+
+#include "server_match_result_strategy.h"
+
+class Server_TournamentMatchResultStrategy : public Server_MatchResultStrategy
+{
+public:
+    bool onGameFinished(Server_Game *game, int playing, Server_AbstractPlayer *lastPlayer) override;
+};
+
+#endif

libcockatrice_network/libcockatrice/network/server/remote/server_protocolhandler.cpp

@@ -3,6 +3,7 @@
 #include "game/game_config.h"
 #include "game/server_game.h"
 #include "game/server_player.h"
+#include "game/server_tournament.h"
 #include "server_database_interface.h"
 #include "server_room.h"
 
@@ -916,6 +917,9 @@ Server_ProtocolHandler::cmdCreateGame(const Command_CreateGame &cmd, Server_Room
     int startingLifeTotal = cmd.has_starting_life_total() ? cmd.starting_life_total() : 20;
 
     bool shareDecklistsOnLoad = cmd.has_share_decklists_on_load() ? cmd.share_decklists_on_load() : false;
+    bool isTournament = cmd.has_is_tournament() ? cmd.is_tournament() : false;
+    int gamesPerMatch =
+        cmd.has_tournament_settings() ? static_cast<int>(cmd.tournament_settings().games_per_match()) : 1;
 
     const int gameId = databaseInterface->getNextGameId();
     if (gameId == -1) {
@@ -940,6 +944,10 @@ Server_ProtocolHandler::cmdCreateGame(const Command_CreateGame &cmd, Server_Room
                       .shareDecklistsOnLoad = shareDecklistsOnLoad};
 
     auto *game = new Server_Game(config, room);
+    game->setIsTournamentGame(isTournament);
+    if (isTournament && game->getTournament()) {
+        game->getTournament()->setGamesPerMatch(static_cast<uint32_t>(qBound(1, gamesPerMatch, MAX_GAMES_PER_MATCH)));
+    }
 
     game->addPlayer(this, rc, asSpectator, asJudge, false);
     room->addGame(game);

libcockatrice_network/libcockatrice/network/server/remote/server_room.cpp

@@ -363,6 +363,18 @@ void Server_Room::broadcastGameListUpdate(const ServerInfo_Game &gameInfo, bool
     sendRoomEvent(prepareRoomEvent(event), sendToIsl);
 }
 
+Server_AbstractUserInterface *Server_Room::getUserInterfaceByName(const QString &name) const
+{
+    usersLock.lockForRead();
+    auto it = users.constFind(name);
+    Server_AbstractUserInterface *result = nullptr;
+    if (it != users.constEnd()) {
+        result = it.value();
+    }
+    usersLock.unlock();
+    return result;
+}
+
 void Server_Room::addGame(Server_Game *game)
 {
     ServerInfo_Room roomInfo;

libcockatrice_network/libcockatrice/network/server/remote/server_room.h

@@ -135,6 +135,8 @@ public:
     void addGame(Server_Game *game);
     void removeGame(Server_Game *game);
 
+    Server_AbstractUserInterface *getUserInterfaceByName(const QString &name) const;
+
     void sendRoomEvent(RoomEvent *event, bool sendToIsl = true);
     RoomEvent *prepareRoomEvent(const ::google::protobuf::Message &roomEvent);
 };

libcockatrice_protocol/libcockatrice/protocol/pb/CMakeLists.txt

@@ -60,6 +60,7 @@ set(PROTO_FILES
     command_set_sideboard_lock.proto
     command_set_sideboard_plan.proto
     command_shuffle.proto
+    command_tournament.proto
     command_undo_draw.proto
     commands.proto
     context_concede.proto
@@ -118,6 +119,7 @@ set(PROTO_FILES
     event_set_card_counter.proto
     event_set_counter.proto
     event_shuffle.proto
+    event_tournament_state.proto
     event_user_joined.proto
     event_user_left.proto
     event_user_message.proto
@@ -184,6 +186,7 @@ set(PROTO_FILES
     serverinfo_replay_match.proto
     serverinfo_report.proto
     serverinfo_room.proto
+    serverinfo_tournament.proto
     serverinfo_user.proto
     serverinfo_user_alt.proto
     serverinfo_user_session.proto

libcockatrice_protocol/libcockatrice/protocol/pb/command_tournament.proto

@@ -0,0 +1,31 @@
+syntax = "proto2";
+import "game_commands.proto";
+import "serverinfo_tournament.proto";
+
+message Command_ReportMatchResult {
+    extend GameCommand {
+        optional Command_ReportMatchResult ext = 1037;
+    }
+
+    optional sint32 game_id = 1 [default = -1];
+    // The winning player's ID. A drawn match is reported with is_draw set and
+    // winner_id left unset so a missing report stays distinguishable from a
+    // reported draw via has_winner_id().
+    optional sint32 winner_id = 2 [default = -1];
+    // Whether the match ended in a draw; winner_id is meaningless then.
+    optional bool is_draw = 3;
+}
+
+message Command_AdvanceTournament {
+    extend GameCommand {
+        optional Command_AdvanceTournament ext = 1038;
+    }
+}
+
+message Command_TournamentSettingsSelect {
+    extend GameCommand {
+        optional Command_TournamentSettingsSelect ext = 1039;
+    }
+
+    optional TournamentSettings settings = 1;
+}

libcockatrice_protocol/libcockatrice/protocol/pb/event_game_state_changed.proto

@@ -24,4 +24,7 @@ message Event_GameStateChanged {
 
     // the amount of seconds since the game started
     optional uint32 seconds_elapsed = 5;
+
+    // for tournament sub-games: the ID of the parent tournament game (-1 if not a sub-game)
+    optional sint32 parent_game_id = 10 [default = -1];
 }

libcockatrice_protocol/libcockatrice/protocol/pb/event_tournament_state.proto

@@ -0,0 +1,22 @@
+syntax = "proto2";
+import "game_event.proto";
+import "serverinfo_tournament.proto";
+
+message Event_TournamentState {
+    extend GameEvent {
+        optional Event_TournamentState ext = 2027;
+    }
+
+    enum TournamentPhase {
+        PHASE_DECK_BUILDING = 0;
+        PHASE_PLAYING = 1;
+        PHASE_FINISHED = 2;
+    }
+
+    optional TournamentPhase phase = 1;
+    optional uint32 current_round = 2;
+    optional uint32 total_rounds = 3;
+    repeated TournamentPlayer players = 4;
+    repeated TournamentPairing pairings = 5;
+    optional TournamentSettings settings = 6;
+}

libcockatrice_protocol/libcockatrice/protocol/pb/game_commands.proto

@@ -180,6 +180,15 @@ message GameCommand {
         /// Server: Server_Player::cmdSetPlaymat
         /// Client: reflected via player properties changed event
         SET_PLAYMAT = 1035;
+
+        /// Report the result of a tournament match sub-game.
+        REPORT_MATCH_RESULT = 1037;
+
+        /// Advance the tournament to the next round.
+        ADVANCE_TOURNAMENT = 1038;
+
+        /// Select tournament settings.
+        TOURNAMENT_SETTINGS_SELECT = 1039;
     }
 
     extensions 100 to max;

libcockatrice_protocol/libcockatrice/protocol/pb/game_event.proto

@@ -34,6 +34,7 @@ message GameEvent {
         CHANGE_ZONE_PROPERTIES = 2020;
         REVERSE_TURN = 2021;
         GAME_LOG_NOTICE = 2022;
+        TOURNAMENT_STATE = 2027;
     }
     optional sint32 player_id = 1 [default = -1];
     extensions 100 to max;

libcockatrice_protocol/libcockatrice/protocol/pb/room_commands.proto

@@ -1,4 +1,5 @@
 syntax = "proto2";
+import "serverinfo_tournament.proto";
 message RoomCommand {
     enum RoomCommandType {
         LEAVE_ROOM = 1000;
@@ -69,6 +70,12 @@ message Command_CreateGame {
 
     // share decklists with all players when selected
     optional bool share_decklists_on_load = 14;
+
+    // tournament settings shared by game creation and mid-game changes
+    optional TournamentSettings tournament_settings = 15;
+
+    // whether this is a tournament game
+    optional bool is_tournament = 16;
 }
 
 message Command_JoinGame {

libcockatrice_protocol/libcockatrice/protocol/pb/serverinfo_game.proto

@@ -65,4 +65,7 @@ message ServerInfo_Game {
 
     // the current host of the game, which may differ from the creator after a host transfer
     optional ServerInfo_User host_info = 53;
+
+    // whether this game is a tournament game
+    optional bool is_tournament = 54;
 }

libcockatrice_protocol/libcockatrice/protocol/pb/serverinfo_tournament.proto

@@ -0,0 +1,32 @@
+syntax = "proto2";
+
+// Player-entered tournament metadata as shown in the standings and bracket views.
+message TournamentPlayer {
+    optional sint32 player_id = 1;
+    optional string player_name = 2;
+    optional uint32 wins = 3;
+    optional uint32 losses = 4;
+    optional uint32 draws = 5;
+    optional bool deck_submitted = 6;
+}
+
+// A single match pairing within a tournament round.
+message TournamentPairing {
+    optional sint32 player1_id = 1;
+    // -1 when the pairing is a bye.
+    optional sint32 player2_id = 2 [default = -1];
+    optional sint32 game_id = 3;
+    // The winning player's ID, or -1 when the match ended in a draw (is_draw).
+    // An unset field reads back as -1 too; has_winner_id() distinguishes those.
+    optional sint32 winner_id = 4 [default = -1];
+    optional uint32 player1_match_wins = 5;
+    optional uint32 player2_match_wins = 6;
+    // Whether the match ended in a draw; winner_id is meaningless then.
+    optional bool is_draw = 7;
+}
+
+// Settings governing all matches of a tournament.
+message TournamentSettings {
+    // Number of games per match (e.g. 3 for best of 3).
+    optional uint32 games_per_match = 1 [default = 1];
+}