feat: 实现补杠和抢杠胡功能

新增 MeldType 和 MeldGroup 领域模型，支持碰、明杠、补杠、暗杠四种副露类型 GameSeat 新增副露管理方法，支持将碰升级为补杠 ResponseActionWindowBuilder 新增补杠响应窗口构建逻辑 SettlementService 新增补杠和抢杠胡结算规则前端新增副露展示区域，支持显示各类副露标签
2026-03-20 14:14:07 +08:00
parent 36dcfb7d31
commit d038a8732d
16 changed files with 633 additions and 29 deletions
--- a/backend/src/main/java/com/xuezhanmaster/game/domain/GameSeat.java
+++ b/backend/src/main/java/com/xuezhanmaster/game/domain/GameSeat.java
@@ -12,6 +12,7 @@ public class GameSeat {
    private final String nickname;
    private final List<Tile> handTiles = new ArrayList<>();
    private final List<Tile> discardTiles = new ArrayList<>();
+    private final List<MeldGroup> meldGroups = new ArrayList<>();
    private TileSuit lackSuit;
    private boolean won;
    private int score;
@@ -51,6 +52,10 @@ public class GameSeat {
        return discardTiles;
    }

+    public List<MeldGroup> getMeldGroups() {
+        return meldGroups;
+    }
+
    public TileSuit getLackSuit() {
        return lackSuit;
    }
@@ -107,6 +112,34 @@ public class GameSeat {
        throw new IllegalStateException("弃牌区不存在指定牌");
    }

+    public void addPengMeld(Tile tile, int sourceSeatNo) {
+        meldGroups.add(new MeldGroup(MeldType.PENG, tile, sourceSeatNo));
+    }
+
+    public void addMingGangMeld(Tile tile, int sourceSeatNo) {
+        meldGroups.add(new MeldGroup(MeldType.MING_GANG, tile, sourceSeatNo));
+    }
+
+    public void upgradePengToBuGang(Tile tile) {
+        for (int i = 0; i < meldGroups.size(); i++) {
+            MeldGroup meldGroup = meldGroups.get(i);
+            if (meldGroup.type() == MeldType.PENG && meldGroup.tile().equals(tile)) {
+                meldGroups.set(i, new MeldGroup(MeldType.BU_GANG, tile, meldGroup.sourceSeatNo()));
+                return;
+            }
+        }
+        throw new IllegalStateException("当前没有可升级为补杠的碰副露");
+    }
+
+    public boolean hasPengMeld(Tile tile) {
+        return meldGroups.stream()
+                .anyMatch(meldGroup -> meldGroup.type() == MeldType.PENG && meldGroup.tile().equals(tile));
+    }
+
+    public void addAnGangMeld(Tile tile) {
+        meldGroups.add(new MeldGroup(MeldType.AN_GANG, tile, null));
+    }
+
    public void declareHu() {
        this.won = true;
    }
--- a/backend/src/main/java/com/xuezhanmaster/game/domain/MeldGroup.java
+++ b/backend/src/main/java/com/xuezhanmaster/game/domain/MeldGroup.java
@@ -0,0 +1,8 @@
+package com.xuezhanmaster.game.domain;
+
+public record MeldGroup(
+        MeldType type,
+        Tile tile,
+        Integer sourceSeatNo
+) {
+}
--- a/backend/src/main/java/com/xuezhanmaster/game/domain/MeldType.java
+++ b/backend/src/main/java/com/xuezhanmaster/game/domain/MeldType.java
@@ -0,0 +1,8 @@
+package com.xuezhanmaster.game.domain;
+
+public enum MeldType {
+    PENG,
+    MING_GANG,
+    BU_GANG,
+    AN_GANG
+}
--- a/backend/src/main/java/com/xuezhanmaster/game/domain/SettlementType.java
+++ b/backend/src/main/java/com/xuezhanmaster/game/domain/SettlementType.java
@@ -2,6 +2,9 @@ package com.xuezhanmaster.game.domain;

 public enum SettlementType {
    DIAN_PAO_HU,
+    QIANG_GANG_HU,
    ZI_MO_HU,
-    MING_GANG
+    BU_GANG,
+    MING_GANG,
+    AN_GANG
 }
--- a/backend/src/main/java/com/xuezhanmaster/game/dto/PublicSeatView.java
+++ b/backend/src/main/java/com/xuezhanmaster/game/dto/PublicSeatView.java
@@ -11,6 +11,7 @@ public record PublicSeatView(
        String lackSuit,
        int score,
        int handCount,
-        List<String> discardTiles
+        List<String> discardTiles,
+        List<String> melds
 ) {
 }
--- a/backend/src/main/java/com/xuezhanmaster/game/dto/SelfSeatView.java
+++ b/backend/src/main/java/com/xuezhanmaster/game/dto/SelfSeatView.java
@@ -10,6 +10,7 @@ public record SelfSeatView(
        String lackSuit,
        int score,
        List<String> handTiles,
-        List<String> discardTiles
+        List<String> discardTiles,
+        List<String> melds
 ) {
 }
--- a/backend/src/main/java/com/xuezhanmaster/game/service/GameActionProcessor.java
+++ b/backend/src/main/java/com/xuezhanmaster/game/service/GameActionProcessor.java
@@ -50,6 +50,10 @@ public class GameActionProcessor {
    private List<GameEvent> gang(GameSession session, String userId, String tileDisplayName, Integer sourceSeatNo) {
        GameTable table = session.getTable();
        GameSeat seat = findSeatByUserId(table, userId);
+        if (sourceSeatNo == null) {
+            validateSelfGang(session, table, seat, tileDisplayName);
+            return List.of();
+        }
        validateResponseAction(session, table, seat, sourceSeatNo, tileDisplayName, "杠");
        return List.of();
    }
@@ -219,6 +223,33 @@ public class GameActionProcessor {
        }
    }

+    private void validateSelfGang(GameSession session, GameTable table, GameSeat actorSeat, String tileDisplayName) {
+        if (table.getPhase() != GamePhase.PLAYING) {
+            throw new BusinessException("GAME_PHASE_INVALID", "当前阶段不允许暗杠");
+        }
+        if (actorSeat.isWon()) {
+            throw new BusinessException("GAME_SEAT_ALREADY_WON", "已胡玩家不能继续杠牌");
+        }
+        if (actorSeat.getSeatNo() != table.getCurrentSeatNo()) {
+            throw new BusinessException("GAME_TURN_INVALID", "当前不是该玩家的回合，不能暗杠");
+        }
+        if (session.getPendingResponseActionWindow() != null) {
+            throw new BusinessException("GAME_ACTION_WINDOW_INVALID", "响应窗口期间不能执行暗杠");
+        }
+        if (isBlank(tileDisplayName)) {
+            throw new BusinessException("GAME_ACTION_PARAM_INVALID", "暗杠动作缺少目标牌");
+        }
+        Tile tile = findTileInHand(actorSeat, tileDisplayName);
+        long sameTileCount = actorSeat.getHandTiles().stream()
+                .filter(handTile -> handTile.equals(tile))
+                .count();
+        boolean canConcealedGang = sameTileCount >= 4;
+        boolean canSupplementalGang = sameTileCount >= 1 && actorSeat.hasPengMeld(tile);
+        if (!canConcealedGang && !canSupplementalGang) {
+            throw new BusinessException("GAME_ACTION_WINDOW_INVALID", "当前手牌不满足暗杠条件");
+        }
+    }
+
    private boolean isBlank(String value) {
        return value == null || value.isBlank();
    }
--- a/backend/src/main/java/com/xuezhanmaster/game/service/GameSessionService.java
+++ b/backend/src/main/java/com/xuezhanmaster/game/service/GameSessionService.java
@@ -147,7 +147,8 @@ public class GameSessionService {
                        self.getLackSuit() == null ? null : self.getLackSuit().name(),
                        self.getScore(),
                        self.getHandTiles().stream().map(Tile::getDisplayName).toList(),
-                        self.getDiscardTiles().stream().map(Tile::getDisplayName).toList()
+                        self.getDiscardTiles().stream().map(Tile::getDisplayName).toList(),
+                        toMeldLabels(self)
                ),
                buildPublicSeats(table)
        );
@@ -210,6 +211,30 @@ public class GameSessionService {
                continue;
            }

+            Optional<String> selfGangCandidate = findSelfGangCandidate(currentSeat);
+            if (selfGangCandidate.isPresent()) {
+                List<GameEvent> gangEvents = gameActionProcessor.process(
+                        session,
+                        new GameActionRequest(
+                                currentSeat.getPlayerId(),
+                                "GANG",
+                                selfGangCandidate.get(),
+                                null
+                        )
+                );
+                appendAndPublish(session, gangEvents);
+                handlePostActionEffects(
+                        session,
+                        ActionType.GANG,
+                        new GameActionRequest(currentSeat.getPlayerId(), "GANG", selfGangCandidate.get(), null),
+                        gangEvents
+                );
+                if (table.getPhase() == GamePhase.FINISHED) {
+                    return;
+                }
+                continue;
+            }
+
            PlayerVisibleGameState visibleState = playerVisibilityService.buildVisibleState(table, currentSeat);
            StrategyDecision decision = strategyService.evaluateDiscard(visibleState);
            List<GameEvent> events = gameActionProcessor.process(
@@ -345,7 +370,8 @@ public class GameSessionService {

    private void handleGangPostAction(GameSession session, GameActionRequest request) {
        if (request.sourceSeatNo() == null) {
-            throw new BusinessException("GAME_ACTION_UNSUPPORTED", "当前仅支持响应明杠，主动杠将在后续迭代补充");
+            handleSelfGangPostAction(session, request.userId(), request.tile());
+            return;
        }
        handleResponseDeclarationPostAction(session, ActionType.GANG, request);
    }
@@ -419,6 +445,10 @@ public class GameSessionService {
        }

        closeResponseWindowAsPass(session, responseActionWindow);
+        if (isSupplementalGangWindow(responseActionWindow)) {
+            executeSupplementalGang(session, responseActionWindow.sourceSeatNo(), responseActionWindow.triggerTile());
+            return;
+        }
        continueAfterDiscardWithoutResponse(session);
    }

@@ -479,7 +509,7 @@ public class GameSessionService {
        switch (resolution.actionType()) {
            case PENG -> executePeng(session, resolution);
            case GANG -> executeGang(session, resolution);
-            case HU -> executeHu(session, resolution);
+            case HU -> executeHu(session, responseActionWindow, resolution);
            default -> throw new BusinessException("GAME_ACTION_INVALID", "未知的响应裁决结果");
        }
    }
@@ -503,6 +533,7 @@ public class GameSessionService {

        winnerSeat.removeMatchingHandTiles(claimedTile, 2);
        sourceSeat.removeMatchingDiscardTile(claimedTile);
+        winnerSeat.addPengMeld(claimedTile, sourceSeat.getSeatNo());
        table.setCurrentSeatNo(winnerSeat.getSeatNo());

        appendAndPublish(session, GameEvent.responseActionDeclared(
@@ -524,6 +555,7 @@ public class GameSessionService {

        winnerSeat.removeMatchingHandTiles(claimedTile, 3);
        sourceSeat.removeMatchingDiscardTile(claimedTile);
+        winnerSeat.addMingGangMeld(claimedTile, sourceSeat.getSeatNo());
        table.setCurrentSeatNo(winnerSeat.getSeatNo());

        appendAndPublish(session, GameEvent.responseActionDeclared(
@@ -562,14 +594,22 @@ public class GameSessionService {
        notifyActionIfHumanTurn(session);
    }

-    private void executeHu(GameSession session, ResponseActionResolution resolution) {
+    private void executeHu(
+            GameSession session,
+            ResponseActionWindow responseActionWindow,
+            ResponseActionResolution resolution
+    ) {
        Tile claimedTile = parseTile(resolution.triggerTile());
        GameTable table = session.getTable();
        GameSeat winnerSeat = table.getSeats().get(resolution.winnerSeatNo());
        GameSeat sourceSeat = table.getSeats().get(resolution.sourceSeatNo());

        winnerSeat.receiveTile(claimedTile);
-        sourceSeat.removeMatchingDiscardTile(claimedTile);
+        if (isSupplementalGangWindow(responseActionWindow)) {
+            sourceSeat.removeMatchingHandTiles(claimedTile, 1);
+        } else {
+            sourceSeat.removeMatchingDiscardTile(claimedTile);
+        }
        winnerSeat.declareHu();

        appendAndPublish(session, GameEvent.responseActionDeclared(
@@ -579,12 +619,21 @@ public class GameSessionService {
                sourceSeat.getSeatNo(),
                claimedTile.getDisplayName()
        ));
-        appendSettlementEvents(session, settlementService.settleDiscardHu(
-                table,
-                winnerSeat.getSeatNo(),
-                sourceSeat.getSeatNo(),
-                claimedTile.getDisplayName()
-        ));
+        if (isSupplementalGangWindow(responseActionWindow)) {
+            appendSettlementEvents(session, settlementService.settleRobbingGangHu(
+                    table,
+                    winnerSeat.getSeatNo(),
+                    sourceSeat.getSeatNo(),
+                    claimedTile.getDisplayName()
+            ));
+        } else {
+            appendSettlementEvents(session, settlementService.settleDiscardHu(
+                    table,
+                    winnerSeat.getSeatNo(),
+                    sourceSeat.getSeatNo(),
+                    claimedTile.getDisplayName()
+            ));
+        }

        if (shouldFinishTable(table)) {
            table.setPhase(GamePhase.FINISHED);
@@ -624,6 +673,102 @@ public class GameSessionService {
        notifyActionIfHumanTurn(session);
    }

+    private void executeSelfGang(GameSession session, String userId, String tileDisplayName) {
+        GameTable table = session.getTable();
+        GameSeat winnerSeat = findSeatByUserId(table, userId);
+        Tile gangTile = parseTile(tileDisplayName);
+
+        winnerSeat.removeMatchingHandTiles(gangTile, 4);
+        winnerSeat.addAnGangMeld(gangTile);
+        table.setCurrentSeatNo(winnerSeat.getSeatNo());
+
+        appendAndPublish(session, GameEvent.responseActionDeclared(
+                session.getGameId(),
+                GameEventType.GANG_DECLARED,
+                winnerSeat.getSeatNo(),
+                null,
+                gangTile.getDisplayName()
+        ));
+        appendSettlementEvents(session, settlementService.settleConcealedGang(
+                table,
+                winnerSeat.getSeatNo(),
+                gangTile.getDisplayName()
+        ));
+
+        if (table.getWallTiles().isEmpty()) {
+            table.setPhase(GamePhase.FINISHED);
+            appendAndPublish(session, GameEvent.phaseChanged(session.getGameId(), table.getPhase().name()));
+            return;
+        }
+
+        Tile drawnTile = table.getWallTiles().remove(0);
+        winnerSeat.receiveTile(drawnTile);
+        appendAndPublish(session, GameEvent.tileDrawn(session.getGameId(), winnerSeat.getSeatNo(), table.getWallTiles().size()));
+        appendAndPublish(session, GameEvent.turnSwitched(session.getGameId(), winnerSeat.getSeatNo()));
+        continueFromResolvedActionTurn(session, winnerSeat);
+    }
+
+    private void handleSelfGangPostAction(GameSession session, String userId, String tileDisplayName) {
+        GameTable table = session.getTable();
+        GameSeat actorSeat = findSeatByUserId(table, userId);
+        Tile gangTile = parseTile(tileDisplayName);
+
+        if (actorSeat.hasPengMeld(gangTile)) {
+            Optional<ResponseActionWindow> window = responseActionWindowBuilder.buildForSupplementalGang(
+                    session,
+                    actorSeat.getSeatNo(),
+                    gangTile
+            );
+            if (window.isPresent()) {
+                openResponseWindow(session, window.get());
+                autoPassAiCandidates(session);
+                if (session.getPendingResponseActionWindow() == null) {
+                    executeSupplementalGang(session, actorSeat.getSeatNo(), tileDisplayName);
+                }
+                return;
+            }
+            executeSupplementalGang(session, actorSeat.getSeatNo(), tileDisplayName);
+            return;
+        }
+
+        executeSelfGang(session, userId, tileDisplayName);
+    }
+
+    private void executeSupplementalGang(GameSession session, int seatNo, String tileDisplayName) {
+        GameTable table = session.getTable();
+        GameSeat winnerSeat = table.getSeats().get(seatNo);
+        Tile gangTile = parseTile(tileDisplayName);
+
+        winnerSeat.removeMatchingHandTiles(gangTile, 1);
+        winnerSeat.upgradePengToBuGang(gangTile);
+        table.setCurrentSeatNo(winnerSeat.getSeatNo());
+
+        appendAndPublish(session, GameEvent.responseActionDeclared(
+                session.getGameId(),
+                GameEventType.GANG_DECLARED,
+                winnerSeat.getSeatNo(),
+                null,
+                gangTile.getDisplayName()
+        ));
+        appendSettlementEvents(session, settlementService.settleSupplementalGang(
+                table,
+                winnerSeat.getSeatNo(),
+                gangTile.getDisplayName()
+        ));
+
+        if (table.getWallTiles().isEmpty()) {
+            table.setPhase(GamePhase.FINISHED);
+            appendAndPublish(session, GameEvent.phaseChanged(session.getGameId(), table.getPhase().name()));
+            return;
+        }
+
+        Tile drawnTile = table.getWallTiles().remove(0);
+        winnerSeat.receiveTile(drawnTile);
+        appendAndPublish(session, GameEvent.tileDrawn(session.getGameId(), winnerSeat.getSeatNo(), table.getWallTiles().size()));
+        appendAndPublish(session, GameEvent.turnSwitched(session.getGameId(), winnerSeat.getSeatNo()));
+        continueFromResolvedActionTurn(session, winnerSeat);
+    }
+
    private ActionType parseActionType(String actionType) {
        try {
            return ActionType.valueOf(actionType.toUpperCase(Locale.ROOT));
@@ -643,7 +788,8 @@ public class GameSessionService {
                        seat.getLackSuit() == null ? null : seat.getLackSuit().name(),
                        seat.getScore(),
                        seat.getHandTiles().size(),
-                        seat.getDiscardTiles().stream().map(Tile::getDisplayName).toList()
+                        seat.getDiscardTiles().stream().map(Tile::getDisplayName).toList(),
+                        toMeldLabels(seat)
                ))
                .toList();
    }
@@ -669,6 +815,10 @@ public class GameSessionService {
        return huEvaluator.canHu(seat.getHandTiles());
    }

+    private boolean isSupplementalGangWindow(ResponseActionWindow responseActionWindow) {
+        return "SUPPLEMENTAL_GANG_DECLARED".equals(responseActionWindow.triggerEventType());
+    }
+
    private long countActiveSeats(GameTable table) {
        return table.getSeats().stream()
                .filter(seat -> !seat.isWon())
@@ -691,7 +841,39 @@ public class GameSessionService {
        if (canSelfDrawHu(currentSeat)) {
            candidates.add(new PrivateActionCandidate(ActionType.HU.name(), null));
        }
+        for (String gangTile : findSelfGangCandidates(currentSeat)) {
+            candidates.add(new PrivateActionCandidate(ActionType.GANG.name(), gangTile));
+        }
        candidates.add(new PrivateActionCandidate(ActionType.DISCARD.name(), null));
        return List.copyOf(candidates);
    }
+
+    private Optional<String> findSelfGangCandidate(GameSeat seat) {
+        List<String> candidates = findSelfGangCandidates(seat);
+        if (candidates.isEmpty()) {
+            return Optional.empty();
+        }
+        return Optional.of(candidates.get(0));
+    }
+
+    private List<String> findSelfGangCandidates(GameSeat seat) {
+        return seat.getHandTiles().stream()
+                .collect(java.util.stream.Collectors.groupingBy(Tile::getDisplayName, java.util.stream.Collectors.counting()))
+                .entrySet().stream()
+                .filter(entry -> entry.getValue() >= 4 || seat.hasPengMeld(parseTile(entry.getKey())))
+                .map(java.util.Map.Entry::getKey)
+                .sorted()
+                .toList();
+    }
+
+    private List<String> toMeldLabels(GameSeat seat) {
+        return seat.getMeldGroups().stream()
+                .map(meld -> switch (meld.type()) {
+                    case PENG -> "碰:" + meld.tile().getDisplayName();
+                    case MING_GANG -> "明杠:" + meld.tile().getDisplayName();
+                    case BU_GANG -> "补杠:" + meld.tile().getDisplayName();
+                    case AN_GANG -> "暗杠:" + meld.tile().getDisplayName();
+                })
+                .toList();
+    }
 }
--- a/backend/src/main/java/com/xuezhanmaster/game/service/ResponseActionWindowBuilder.java
+++ b/backend/src/main/java/com/xuezhanmaster/game/service/ResponseActionWindowBuilder.java
@@ -55,6 +55,40 @@ public class ResponseActionWindowBuilder {
        ));
    }

+    public Optional<ResponseActionWindow> buildForSupplementalGang(GameSession session, int sourceSeatNo, Tile gangTile) {
+        GameTable table = session.getTable();
+        List<ResponseActionSeatCandidate> seatCandidates = new ArrayList<>();
+
+        for (GameSeat seat : table.getSeats()) {
+            if (seat.getSeatNo() == sourceSeatNo || seat.isWon()) {
+                continue;
+            }
+            if (!huEvaluator.canHuWithClaimedTile(seat.getHandTiles(), gangTile)) {
+                continue;
+            }
+            seatCandidates.add(new ResponseActionSeatCandidate(
+                    seat.getSeatNo(),
+                    seat.getPlayerId(),
+                    List.of(
+                            new ResponseActionOption(ActionType.HU, gangTile.getDisplayName()),
+                            new ResponseActionOption(ActionType.PASS, null)
+                    )
+            ));
+        }
+
+        if (seatCandidates.isEmpty()) {
+            return Optional.empty();
+        }
+
+        return Optional.of(ResponseActionWindow.create(
+                session.getGameId(),
+                "SUPPLEMENTAL_GANG_DECLARED",
+                sourceSeatNo,
+                gangTile.getDisplayName(),
+                seatCandidates
+        ));
+    }
+
    private List<ResponseActionOption> buildSeatOptions(GameSeat seat, Tile discardedTile) {
        int sameTileCount = countSameTileInHand(seat, discardedTile);
        boolean canHu = huEvaluator.canHuWithClaimedTile(seat.getHandTiles(), discardedTile);
--- a/backend/src/main/java/com/xuezhanmaster/game/service/SettlementService.java
+++ b/backend/src/main/java/com/xuezhanmaster/game/service/SettlementService.java
@@ -18,7 +18,9 @@ public class SettlementService {

    private static final int DIAN_PAO_HU_SCORE = 1;
    private static final int ZI_MO_HU_SCORE = 1;
+    private static final int BU_GANG_SCORE = 1;
    private static final int MING_GANG_SCORE = 1;
+    private static final int AN_GANG_SCORE = 2;

    public SettlementResult settleDiscardHu(
            GameTable table,
@@ -80,6 +82,75 @@ public class SettlementService {
        );
    }

+    public SettlementResult settleRobbingGangHu(
+            GameTable table,
+            int winnerSeatNo,
+            int sourceSeatNo,
+            String triggerTile
+    ) {
+        return applySettlement(
+                table,
+                SettlementType.QIANG_GANG_HU,
+                ActionType.HU,
+                winnerSeatNo,
+                sourceSeatNo,
+                triggerTile,
+                orderedDeltas(winnerSeatNo, DIAN_PAO_HU_SCORE, sourceSeatNo, -DIAN_PAO_HU_SCORE)
+        );
+    }
+
+    public SettlementResult settleSupplementalGang(
+            GameTable table,
+            int winnerSeatNo,
+            String triggerTile
+    ) {
+        Map<Integer, Integer> scoreDeltas = new LinkedHashMap<>();
+        int totalWinScore = 0;
+        for (GameSeat seat : table.getSeats()) {
+            if (seat.getSeatNo() == winnerSeatNo || seat.isWon()) {
+                continue;
+            }
+            scoreDeltas.put(seat.getSeatNo(), -BU_GANG_SCORE);
+            totalWinScore += BU_GANG_SCORE;
+        }
+        scoreDeltas.put(winnerSeatNo, totalWinScore);
+        return applySettlement(
+                table,
+                SettlementType.BU_GANG,
+                ActionType.GANG,
+                winnerSeatNo,
+                winnerSeatNo,
+                triggerTile,
+                scoreDeltas
+        );
+    }
+
+    public SettlementResult settleConcealedGang(
+            GameTable table,
+            int winnerSeatNo,
+            String triggerTile
+    ) {
+        Map<Integer, Integer> scoreDeltas = new LinkedHashMap<>();
+        int totalWinScore = 0;
+        for (GameSeat seat : table.getSeats()) {
+            if (seat.getSeatNo() == winnerSeatNo || seat.isWon()) {
+                continue;
+            }
+            scoreDeltas.put(seat.getSeatNo(), -AN_GANG_SCORE);
+            totalWinScore += AN_GANG_SCORE;
+        }
+        scoreDeltas.put(winnerSeatNo, totalWinScore);
+        return applySettlement(
+                table,
+                SettlementType.AN_GANG,
+                ActionType.GANG,
+                winnerSeatNo,
+                winnerSeatNo,
+                triggerTile,
+                scoreDeltas
+        );
+    }
+
    private SettlementResult applySettlement(
            GameTable table,
            SettlementType settlementType,
--- a/backend/src/main/java/com/xuezhanmaster/teaching/service/PlayerVisibilityService.java
+++ b/backend/src/main/java/com/xuezhanmaster/teaching/service/PlayerVisibilityService.java
@@ -14,10 +14,14 @@ public class PlayerVisibilityService {

    public PlayerVisibleGameState buildVisibleState(GameTable table, GameSeat seat) {
        List<String> publicDiscards = new ArrayList<>();
+        List<String> publicMelds = new ArrayList<>();
        for (GameSeat gameSeat : table.getSeats()) {
            for (Tile tile : gameSeat.getDiscardTiles()) {
                publicDiscards.add(gameSeat.getSeatNo() + ":" + tile.getDisplayName());
            }
+            gameSeat.getMeldGroups().forEach(meld ->
+                    publicMelds.add(gameSeat.getSeatNo() + ":" + meld.type().name() + ":" + meld.tile().getDisplayName())
+            );
        }

        return new PlayerVisibleGameState(
@@ -26,8 +30,7 @@ public class PlayerVisibilityService {
                seat.getLackSuit(),
                List.copyOf(seat.getHandTiles()),
                publicDiscards,
-                List.of()
+                publicMelds
        );
    }
 }
-