Kotlin migration: Spring server

53 files changed, 995 insertions, 1424 deletions

diff --git a/backend/src/main/java/org/luxons/sevenwonders/SevenWonders.java b/backend/src/main/java/org/luxons/sevenwonders/SevenWonders.java
deleted file mode 100644
index c656b2c3..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/SevenWonders.java
+++ /dev/null
@@ -1,14 +0,0 @@
-package org.luxons.sevenwonders;
-
-import org.hildan.livedoc.spring.boot.starter.EnableJSONDoc;
-import org.springframework.boot.SpringApplication;
-import org.springframework.boot.autoconfigure.SpringBootApplication;
-
-@SpringBootApplication
-@EnableJSONDoc
-public class SevenWonders {
-
-    public static void main(String[] args) {
-        SpringApplication.run(SevenWonders.class, args);
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/actions/ChooseNameAction.java b/backend/src/main/java/org/luxons/sevenwonders/actions/ChooseNameAction.java
deleted file mode 100644
index c404cd74..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/actions/ChooseNameAction.java
+++ /dev/null
@@ -1,30 +0,0 @@
-package org.luxons.sevenwonders.actions;
-
-import javax.validation.constraints.NotNull;
-import javax.validation.constraints.Size;
-
-import org.hildan.livedoc.core.annotations.types.ApiType;
-import org.hildan.livedoc.core.annotations.types.ApiTypeProperty;
-
-/**
- * The action to choose the player's name. This is the first action that should be called.
- */
-@ApiType(group = "Actions")
-public class ChooseNameAction {
-
-    @NotNull
-    @Size(min = 2, max = 20)
-    private String playerName;
-
-    /**
-     * @return The display name of the player. May contain spaces and special characters.
-     */
-    @ApiTypeProperty(required = true)
-    public String getPlayerName() {
-        return playerName;
-    }
-
-    public void setPlayerName(String playerName) {
-        this.playerName = playerName;
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/actions/CreateGameAction.java b/backend/src/main/java/org/luxons/sevenwonders/actions/CreateGameAction.java
deleted file mode 100644
index 771a5a9c..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/actions/CreateGameAction.java
+++ /dev/null
@@ -1,30 +0,0 @@
-package org.luxons.sevenwonders.actions;
-
-import javax.validation.constraints.NotNull;
-import javax.validation.constraints.Size;
-
-import org.hildan.livedoc.core.annotations.types.ApiType;
-
-/**
- * The action to create a game.
- */
-@ApiType(group = "Actions")
-public class CreateGameAction {
-
-    @NotNull
-    @Size(min = 2, max = 30)
-    private String gameName;
-
-    /**
-     * @return The name of the game to create
-     */
-    public String getGameName() {
-        return gameName;
-    }
-
-    public void setGameName(String gameName) {
-        this.gameName = gameName;
-    }
-}
-
-
diff --git a/backend/src/main/java/org/luxons/sevenwonders/actions/JoinGameAction.java b/backend/src/main/java/org/luxons/sevenwonders/actions/JoinGameAction.java
deleted file mode 100644
index 2675dc71..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/actions/JoinGameAction.java
+++ /dev/null
@@ -1,27 +0,0 @@
-package org.luxons.sevenwonders.actions;
-
-import javax.validation.constraints.NotNull;
-
-import org.hildan.livedoc.core.annotations.types.ApiType;
-import org.luxons.sevenwonders.doc.Documentation;
-
-/**
- * The action to join a game.
- */
-@ApiType(group = Documentation.GROUP_ACTIONS)
-public class JoinGameAction {
-
-    @NotNull
-    private Long gameId;
-
-    /**
-     * @return The ID of the game to join
-     */
-    public Long getGameId() {
-        return gameId;
-    }
-
-    public void setGameId(Long gameId) {
-        this.gameId = gameId;
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/actions/PrepareMoveAction.java b/backend/src/main/java/org/luxons/sevenwonders/actions/PrepareMoveAction.java
deleted file mode 100644
index e3622b1b..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/actions/PrepareMoveAction.java
+++ /dev/null
@@ -1,28 +0,0 @@
-package org.luxons.sevenwonders.actions;
-
-import javax.validation.constraints.NotNull;
-
-import org.hildan.livedoc.core.annotations.types.ApiType;
-import org.luxons.sevenwonders.doc.Documentation;
-import org.luxons.sevenwonders.game.api.PlayerMove;
-
-/**
- * The action to prepare the next move during a game.
- */
-@ApiType(group = Documentation.GROUP_ACTIONS)
-public class PrepareMoveAction {
-
-    @NotNull
-    private PlayerMove move;
-
-    /**
-     * @return the move to prepare
-     */
-    public PlayerMove getMove() {
-        return move;
-    }
-
-    public void setMove(PlayerMove move) {
-        this.move = move;
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/actions/ReorderPlayersAction.java b/backend/src/main/java/org/luxons/sevenwonders/actions/ReorderPlayersAction.java
deleted file mode 100644
index ce272340..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/actions/ReorderPlayersAction.java
+++ /dev/null
@@ -1,29 +0,0 @@
-package org.luxons.sevenwonders.actions;
-
-import java.util.List;
-import javax.validation.constraints.NotNull;
-
-import org.hildan.livedoc.core.annotations.types.ApiType;
-import org.luxons.sevenwonders.doc.Documentation;
-
-/**
- * The action to update the order of the players around the table. Can only be called in the lobby by the owner of the
- * game.
- */
-@ApiType(group = Documentation.GROUP_ACTIONS)
-public class ReorderPlayersAction {
-
-    @NotNull
-    private List<String> orderedPlayers;
-
-    /**
-     * @return the list of usernames of the players, in the new order
-     */
-    public List<String> getOrderedPlayers() {
-        return orderedPlayers;
-    }
-
-    public void setOrderedPlayers(List<String> orderedPlayers) {
-        this.orderedPlayers = orderedPlayers;
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/actions/UpdateSettingsAction.java b/backend/src/main/java/org/luxons/sevenwonders/actions/UpdateSettingsAction.java
deleted file mode 100644
index 7c48dee1..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/actions/UpdateSettingsAction.java
+++ /dev/null
@@ -1,28 +0,0 @@
-package org.luxons.sevenwonders.actions;
-
-import javax.validation.constraints.NotNull;
-
-import org.hildan.livedoc.core.annotations.types.ApiType;
-import org.luxons.sevenwonders.doc.Documentation;
-import org.luxons.sevenwonders.game.api.CustomizableSettings;
-
-/**
- * The action to update the settings of the game. Can only be called in the lobby by the owner of the game.
- */
-@ApiType(group = Documentation.GROUP_ACTIONS)
-public class UpdateSettingsAction {
-
-    @NotNull
-    private CustomizableSettings settings;
-
-    /**
-     * @return the new values for the settings
-     */
-    public CustomizableSettings getSettings() {
-        return settings;
-    }
-
-    public void setSettings(CustomizableSettings settings) {
-        this.settings = settings;
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/config/AnonymousUsersHandshakeHandler.java b/backend/src/main/java/org/luxons/sevenwonders/config/AnonymousUsersHandshakeHandler.java
deleted file mode 100644
index bebbd477..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/config/AnonymousUsersHandshakeHandler.java
+++ /dev/null
@@ -1,24 +0,0 @@
-package org.luxons.sevenwonders.config;
-
-import java.security.Principal;
-import java.util.Map;
-
-import org.springframework.http.server.ServerHttpRequest;
-import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
-import org.springframework.web.socket.WebSocketHandler;
-import org.springframework.web.socket.server.support.DefaultHandshakeHandler;
-
-class AnonymousUsersHandshakeHandler extends DefaultHandshakeHandler {
-
-    private int playerId = 0;
-
-    @Override
-    public Principal determineUser(ServerHttpRequest request, WebSocketHandler wsHandler,
-            Map<String, Object> attributes) {
-        Principal p = super.determineUser(request, wsHandler, attributes);
-        if (p == null) {
-            p = new UsernamePasswordAuthenticationToken("player" + playerId++, null);
-        }
-        return p;
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/config/TopicSubscriptionInterceptor.java b/backend/src/main/java/org/luxons/sevenwonders/config/TopicSubscriptionInterceptor.java
deleted file mode 100644
index 855b7800..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/config/TopicSubscriptionInterceptor.java
+++ /dev/null
@@ -1,43 +0,0 @@
-package org.luxons.sevenwonders.config;
-
-import org.luxons.sevenwonders.validation.DestinationAccessValidator;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.messaging.Message;
-import org.springframework.messaging.MessageChannel;
-import org.springframework.messaging.simp.stomp.StompCommand;
-import org.springframework.messaging.simp.stomp.StompHeaderAccessor;
-import org.springframework.messaging.support.ChannelInterceptorAdapter;
-import org.springframework.stereotype.Component;
-
-@Component
-public class TopicSubscriptionInterceptor extends ChannelInterceptorAdapter {
-
-    private static final Logger logger = LoggerFactory.getLogger(TopicSubscriptionInterceptor.class);
-
-    private final DestinationAccessValidator destinationAccessValidator;
-
-    @Autowired
-    public TopicSubscriptionInterceptor(DestinationAccessValidator destinationAccessValidator) {
-        this.destinationAccessValidator = destinationAccessValidator;
-    }
-
-    @Override
-    public Message<?> preSend(Message<?> message, MessageChannel channel) {
-        StompHeaderAccessor headerAccessor = StompHeaderAccessor.wrap(message);
-        if (StompCommand.SUBSCRIBE.equals(headerAccessor.getCommand())) {
-            String username = headerAccessor.getUser().getName();
-            String destination = headerAccessor.getDestination();
-            if (!destinationAccessValidator.hasAccess(username, destination)) {
-                sendForbiddenSubscriptionError(username, destination);
-                return null;
-            }
-        }
-        return message;
-    }
-
-    private void sendForbiddenSubscriptionError(String username, String destination) {
-        logger.error(String.format("Player '%s' is not allowed to access %s", username, destination));
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/config/WebSecurityConfig.java b/backend/src/main/java/org/luxons/sevenwonders/config/WebSecurityConfig.java
deleted file mode 100644
index 2cfb966d..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/config/WebSecurityConfig.java
+++ /dev/null
@@ -1,13 +0,0 @@
-package org.luxons.sevenwonders.config;
-
-import org.springframework.context.annotation.Configuration;
-import org.springframework.security.config.annotation.web.builders.HttpSecurity;
-import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
-
-@Configuration
-public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
-    @Override
-    protected void configure(HttpSecurity httpSecurity) {
-        // this disables default authentication settings
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/config/WebSocketConfig.java b/backend/src/main/java/org/luxons/sevenwonders/config/WebSocketConfig.java
deleted file mode 100644
index b8018a86..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/config/WebSocketConfig.java
+++ /dev/null
@@ -1,51 +0,0 @@
-package org.luxons.sevenwonders.config;
-
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
-import org.springframework.messaging.simp.config.ChannelRegistration;
-import org.springframework.messaging.simp.config.MessageBrokerRegistry;
-import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
-import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
-import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
-import org.springframework.web.socket.server.support.DefaultHandshakeHandler;
-
-@Configuration
-@EnableWebSocketMessageBroker
-public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
-
-    private final TopicSubscriptionInterceptor topicSubscriptionInterceptor;
-
-    @Autowired
-    public WebSocketConfig(TopicSubscriptionInterceptor topicSubscriptionInterceptor) {
-        this.topicSubscriptionInterceptor = topicSubscriptionInterceptor;
-    }
-
-    @Override
-    public void configureMessageBroker(MessageBrokerRegistry config) {
-        // prefixes for all subscriptions
-        config.enableSimpleBroker("/queue", "/topic");
-        config.setUserDestinationPrefix("/user");
-
-        // /app for normal calls, /topic for subscription events
-        config.setApplicationDestinationPrefixes("/app", "/topic");
-    }
-
-    @Override
-    public void registerStompEndpoints(StompEndpointRegistry registry) {
-        registry.addEndpoint("/seven-wonders-websocket")
-                .setHandshakeHandler(handshakeHandler())
-                .setAllowedOrigins("http://localhost:3000") // to allow frontend server proxy requests in dev mode
-                .withSockJS();
-    }
-
-    @Bean
-    public DefaultHandshakeHandler handshakeHandler() {
-        return new AnonymousUsersHandshakeHandler();
-    }
-
-    @Override
-    public void configureClientInboundChannel(ChannelRegistration registration) {
-        registration.interceptors(topicSubscriptionInterceptor);
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/controllers/GameBrowserController.java b/backend/src/main/java/org/luxons/sevenwonders/controllers/GameBrowserController.java
deleted file mode 100644
index 9bb96559..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/controllers/GameBrowserController.java
+++ /dev/null
@@ -1,129 +0,0 @@
-package org.luxons.sevenwonders.controllers;
-
-import java.security.Principal;
-import java.util.Collection;
-import java.util.Collections;
-
-import org.hildan.livedoc.core.annotations.Api;
-import org.luxons.sevenwonders.actions.CreateGameAction;
-import org.luxons.sevenwonders.actions.JoinGameAction;
-import org.luxons.sevenwonders.errors.ApiMisuseException;
-import org.luxons.sevenwonders.lobby.Lobby;
-import org.luxons.sevenwonders.lobby.Player;
-import org.luxons.sevenwonders.repositories.LobbyRepository;
-import org.luxons.sevenwonders.repositories.PlayerRepository;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.messaging.handler.annotation.MessageMapping;
-import org.springframework.messaging.simp.SimpMessagingTemplate;
-import org.springframework.messaging.simp.annotation.SendToUser;
-import org.springframework.messaging.simp.annotation.SubscribeMapping;
-import org.springframework.stereotype.Controller;
-import org.springframework.validation.annotation.Validated;
-
-/**
- * This is the place where the player looks for a game.
- */
-@Api(name = "GameBrowser")
-@Controller
-public class GameBrowserController {
-
-    private static final Logger logger = LoggerFactory.getLogger(GameBrowserController.class);
-
-    private final LobbyController lobbyController;
-
-    private final LobbyRepository lobbyRepository;
-
-    private final PlayerRepository playerRepository;
-
-    private final SimpMessagingTemplate template;
-
-    @Autowired
-    public GameBrowserController(LobbyController lobbyController, LobbyRepository lobbyRepository,
-            PlayerRepository playerRepository, SimpMessagingTemplate template) {
-        this.lobbyController = lobbyController;
-        this.lobbyRepository = lobbyRepository;
-        this.playerRepository = playerRepository;
-        this.template = template;
-    }
-
-    /**
-     * Gets the created or updated games. The list of existing games is received on this topic at once upon
-     * subscription, and then each time the list changes.
-     *
-     * @param principal
-     *         the connected user's information
-     *
-     * @return the current list of {@link Lobby}s
-     */
-    @SubscribeMapping("/games") // prefix /topic not shown
-    public Collection<Lobby> listGames(Principal principal) {
-        logger.info("Player '{}' subscribed to /topic/games", principal.getName());
-        return lobbyRepository.list();
-    }
-
-    /**
-     * Creates a new {@link Lobby}.
-     *
-     * @param action
-     *         the action to create the game
-     * @param principal
-     *         the connected user's information
-     *
-     * @return the newly created {@link Lobby}
-     */
-    @MessageMapping("/lobby/create")
-    @SendToUser("/queue/lobby/joined")
-    public Lobby createGame(@Validated CreateGameAction action, Principal principal) {
-        checkThatUserIsNotInAGame(principal, "cannot create another game");
-
-        Player gameOwner = playerRepository.find(principal.getName());
-        Lobby lobby = lobbyRepository.create(action.getGameName(), gameOwner);
-
-        logger.info("Game '{}' ({}) created by {} ({})", lobby.getName(), lobby.getId(), gameOwner.getDisplayName(),
-                gameOwner.getUsername());
-
-        // notify everyone that a new game exists
-        template.convertAndSend("/topic/games", Collections.singletonList(lobby));
-        return lobby;
-    }
-
-    /**
-     * Joins an existing {@link Lobby}.
-     *
-     * @param action
-     *         the action to join the game
-     * @param principal
-     *         the connected user's information
-     *
-     * @return the {@link Lobby} that has just been joined
-     */
-    @MessageMapping("/lobby/join")
-    @SendToUser("/queue/lobby/joined")
-    public Lobby joinGame(@Validated JoinGameAction action, Principal principal) {
-        checkThatUserIsNotInAGame(principal, "cannot join another game");
-
-        Lobby lobby = lobbyRepository.find(action.getGameId());
-        Player newPlayer = playerRepository.find(principal.getName());
-        lobby.addPlayer(newPlayer);
-
-        logger.info("Player '{}' ({}) joined game {}", newPlayer.getDisplayName(), newPlayer.getUsername(),
-                lobby.getName());
-        lobbyController.sendLobbyUpdateToPlayers(lobby);
-        return lobby;
-    }
-
-    private void checkThatUserIsNotInAGame(Principal principal, String impossibleActionDescription) {
-        Lobby lobby = playerRepository.find(principal.getName()).getLobby();
-        if (lobby != null) {
-            throw new UserAlreadyInGameException(lobby.getName(), impossibleActionDescription);
-        }
-    }
-
-    static class UserAlreadyInGameException extends ApiMisuseException {
-        UserAlreadyInGameException(String gameName, String impossibleActionDescription) {
-            super("Client already in game '" + gameName + "', " + impossibleActionDescription);
-        }
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/controllers/GameController.java b/backend/src/main/java/org/luxons/sevenwonders/controllers/GameController.java
deleted file mode 100644
index f8d60ece..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/controllers/GameController.java
+++ /dev/null
@@ -1,111 +0,0 @@
-package org.luxons.sevenwonders.controllers;
-
-import java.security.Principal;
-import java.util.List;
-
-import org.hildan.livedoc.core.annotations.Api;
-import org.luxons.sevenwonders.actions.PrepareMoveAction;
-import org.luxons.sevenwonders.game.Game;
-import org.luxons.sevenwonders.game.api.PlayerTurnInfo;
-import org.luxons.sevenwonders.game.api.Table;
-import org.luxons.sevenwonders.game.cards.CardBack;
-import org.luxons.sevenwonders.lobby.Lobby;
-import org.luxons.sevenwonders.lobby.Player;
-import org.luxons.sevenwonders.output.PreparedCard;
-import org.luxons.sevenwonders.repositories.PlayerRepository;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.messaging.handler.annotation.MessageMapping;
-import org.springframework.messaging.simp.SimpMessagingTemplate;
-import org.springframework.stereotype.Controller;
-
-/**
- * This API is for in-game events management.
- */
-@Api(name = "Game")
-@Controller
-public class GameController {
-
-    private static final Logger logger = LoggerFactory.getLogger(GameController.class);
-
-    private final SimpMessagingTemplate template;
-
-    private final PlayerRepository playerRepository;
-
-    @Autowired
-    public GameController(SimpMessagingTemplate template, PlayerRepository playerRepository) {
-        this.template = template;
-        this.playerRepository = playerRepository;
-    }
-
-    /**
-     * Notifies the game that the player is ready to receive his hand.
-     *
-     * @param principal
-     *         the connected user's information
-     */
-    @MessageMapping("/game/sayReady")
-    public void ready(Principal principal) {
-        Player player = playerRepository.find(principal.getName());
-        player.setReady(true);
-        Game game = player.getGame();
-        logger.info("Game {}: player {} is ready for the next turn", game.getId(), player);
-
-        Lobby lobby = player.getLobby();
-        List<Player> players = lobby.getPlayers();
-
-        boolean allReady = players.stream().allMatch(Player::isReady);
-        if (allReady) {
-            logger.info("Game {}: all players ready, sending turn info", game.getId());
-            players.forEach(p -> p.setReady(false));
-            sendTurnInfo(players, game);
-        } else {
-            sendPlayerReady(game.getId(), player);
-        }
-    }
-
-    private void sendTurnInfo(List<Player> players, Game game) {
-        for (PlayerTurnInfo turnInfo : game.getCurrentTurnInfo()) {
-            Player player = players.get(turnInfo.getPlayerIndex());
-            template.convertAndSendToUser(player.getUsername(), "/queue/game/turn", turnInfo);
-        }
-    }
-
-    private void sendPlayerReady(long gameId, Player player) {
-        template.convertAndSend("/topic/game/" + gameId + "/playerReady", player.getUsername());
-    }
-
-    /**
-     * Prepares the player's next move. When all players have prepared their moves, all moves are executed.
-     *
-     * @param action
-     *         the action to prepare the move
-     * @param principal
-     *         the connected user's information
-     */
-    @MessageMapping("/game/prepareMove")
-    public void prepareMove(PrepareMoveAction action, Principal principal) {
-        Player player = playerRepository.find(principal.getName());
-        Game game = player.getGame();
-        CardBack preparedCardBack = game.prepareMove(player.getIndex(), action.getMove());
-        PreparedCard preparedCard = new PreparedCard(player, preparedCardBack);
-        logger.info("Game {}: player {} prepared move {}", game.getId(), principal.getName(), action.getMove());
-
-        if (game.allPlayersPreparedTheirMove()) {
-            logger.info("Game {}: all players have prepared their move, executing turn...", game.getId());
-            Table table = game.playTurn();
-            sendPlayedMoves(game.getId(), table);
-        } else {
-            sendPreparedCard(game.getId(), preparedCard);
-        }
-    }
-
-    private void sendPlayedMoves(long gameId, Table table) {
-        template.convertAndSend("/topic/game/" + gameId + "/tableUpdates", table);
-    }
-
-    private void sendPreparedCard(long gameId, PreparedCard preparedCard) {
-        template.convertAndSend("/topic/game/" + gameId + "/prepared", preparedCard);
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/controllers/HomeController.java b/backend/src/main/java/org/luxons/sevenwonders/controllers/HomeController.java
deleted file mode 100644
index 97bc8b67..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/controllers/HomeController.java
+++ /dev/null
@@ -1,52 +0,0 @@
-package org.luxons.sevenwonders.controllers;
-
-import java.security.Principal;
-
-import org.hildan.livedoc.core.annotations.Api;
-import org.luxons.sevenwonders.actions.ChooseNameAction;
-import org.luxons.sevenwonders.lobby.Player;
-import org.luxons.sevenwonders.repositories.PlayerRepository;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.messaging.handler.annotation.MessageMapping;
-import org.springframework.messaging.simp.annotation.SendToUser;
-import org.springframework.stereotype.Controller;
-import org.springframework.validation.annotation.Validated;
-
-/**
- * Handles actions in the homepage of the game.
- */
-@Api(name = "Home")
-@Controller
-public class HomeController {
-
-    private static final Logger logger = LoggerFactory.getLogger(HomeController.class);
-
-    private final PlayerRepository playerRepository;
-
-    @Autowired
-    public HomeController(PlayerRepository playerRepository) {
-        this.playerRepository = playerRepository;
-    }
-
-    /**
-     * Creates/updates the player's name (for the user's session).
-     *
-     * @param action
-     *         the action to choose the name of the player
-     * @param principal
-     *         the connected user's information
-     *
-     * @return the created {@link Player} object
-     */
-    @MessageMapping("/chooseName")
-    @SendToUser("/queue/nameChoice")
-    public Player chooseName(@Validated ChooseNameAction action, Principal principal) {
-        String username = principal.getName();
-        Player player = playerRepository.createOrUpdate(username, action.getPlayerName());
-
-        logger.info("Player '{}' chose the name '{}'", username, player.getDisplayName());
-        return player;
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/controllers/LobbyController.java b/backend/src/main/java/org/luxons/sevenwonders/controllers/LobbyController.java
deleted file mode 100644
index 330a0f7f..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/controllers/LobbyController.java
+++ /dev/null
@@ -1,141 +0,0 @@
-package org.luxons.sevenwonders.controllers;
-
-import java.security.Principal;
-import java.util.Collections;
-
-import org.hildan.livedoc.core.annotations.Api;
-import org.luxons.sevenwonders.actions.ReorderPlayersAction;
-import org.luxons.sevenwonders.actions.UpdateSettingsAction;
-import org.luxons.sevenwonders.errors.ApiMisuseException;
-import org.luxons.sevenwonders.game.Game;
-import org.luxons.sevenwonders.lobby.Lobby;
-import org.luxons.sevenwonders.lobby.Player;
-import org.luxons.sevenwonders.repositories.PlayerRepository;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.messaging.handler.annotation.MessageMapping;
-import org.springframework.messaging.simp.SimpMessagingTemplate;
-import org.springframework.stereotype.Controller;
-import org.springframework.validation.annotation.Validated;
-
-/**
- * Handles actions in the game's lobby. The lobby is the place where players gather before a game.
- */
-@Api(name = "Lobby")
-@Controller
-public class LobbyController {
-
-    private static final Logger logger = LoggerFactory.getLogger(LobbyController.class);
-
-    private final PlayerRepository playerRepository;
-
-    private final SimpMessagingTemplate template;
-
-    @Autowired
-    public LobbyController(PlayerRepository playerRepository, SimpMessagingTemplate template) {
-        this.playerRepository = playerRepository;
-        this.template = template;
-    }
-
-    /**
-     * Leaves the current lobby.
-     *
-     * @param principal
-     *         the connected user's information
-     */
-    @MessageMapping("/lobby/leave")
-    public void leave(Principal principal) {
-        Lobby lobby = getLobby(principal);
-        Player player = lobby.removePlayer(principal.getName());
-
-        logger.info("Player {} left game '{}'", player, lobby.getName());
-        sendLobbyUpdateToPlayers(lobby);
-    }
-
-    /**
-     * Reorders the players in the current lobby. This can only be done by the lobby's owner.
-     *
-     * @param action
-     *         the action to reorder the players
-     * @param principal
-     *         the connected user's information
-     */
-    @MessageMapping("/lobby/reorderPlayers")
-    public void reorderPlayers(@Validated ReorderPlayersAction action, Principal principal) {
-        Lobby lobby = getOwnedLobby(principal);
-        lobby.reorderPlayers(action.getOrderedPlayers());
-
-        logger.info("Players in game '{}' reordered to {}", lobby.getName(), action.getOrderedPlayers());
-        sendLobbyUpdateToPlayers(lobby);
-    }
-
-    /**
-     * Updates the game settings. This can only be done by the lobby's owner.
-     *
-     * @param action
-     *         the action to update the settings
-     * @param principal
-     *         the connected user's information
-     */
-    @MessageMapping("/lobby/updateSettings")
-    public void updateSettings(@Validated UpdateSettingsAction action, Principal principal) {
-        Lobby lobby = getOwnedLobby(principal);
-        lobby.setSettings(action.getSettings());
-
-        logger.info("Updated settings of game '{}'", lobby.getName());
-        sendLobbyUpdateToPlayers(lobby);
-    }
-
-    void sendLobbyUpdateToPlayers(Lobby lobby) {
-        template.convertAndSend("/topic/lobby/" + lobby.getId() + "/updated", lobby);
-        template.convertAndSend("/topic/games", Collections.singletonList(lobby));
-    }
-
-    /**
-     * Starts the game.
-     *
-     * @param principal
-     *         the connected user's information
-     */
-    @MessageMapping("/lobby/startGame")
-    public void startGame(Principal principal) {
-        Lobby lobby = getOwnedLobby(principal);
-        Game game = lobby.startGame();
-
-        logger.info("Game {} successfully started", game.getId());
-        template.convertAndSend("/topic/lobby/" + lobby.getId() + "/started", "");
-    }
-
-    private Lobby getOwnedLobby(Principal principal) {
-        Lobby lobby = getLobby(principal);
-        if (!lobby.isOwner(principal.getName())) {
-            throw new PlayerIsNotOwnerException(principal.getName());
-        }
-        return lobby;
-    }
-
-    private Lobby getLobby(Principal principal) {
-        Lobby lobby = getPlayer(principal).getLobby();
-        if (lobby == null) {
-            throw new PlayerNotInLobbyException(principal.getName());
-        }
-        return lobby;
-    }
-
-    private Player getPlayer(Principal principal) {
-        return playerRepository.find(principal.getName());
-    }
-
-    static class PlayerNotInLobbyException extends ApiMisuseException {
-        PlayerNotInLobbyException(String username) {
-            super("User " + username + " is not in a lobby, create or join a game first");
-        }
-    }
-
-    static class PlayerIsNotOwnerException extends ApiMisuseException {
-        PlayerIsNotOwnerException(String username) {
-            super("User " + username + " does not own the lobby he's in");
-        }
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/doc/Documentation.java b/backend/src/main/java/org/luxons/sevenwonders/doc/Documentation.java
deleted file mode 100644
index e27bc2ff..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/doc/Documentation.java
+++ /dev/null
@@ -1,6 +0,0 @@
-package org.luxons.sevenwonders.doc;
-
-public class Documentation {
-
-    public static final String GROUP_ACTIONS = "Actions";
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/errors/ApiMisuseException.java b/backend/src/main/java/org/luxons/sevenwonders/errors/ApiMisuseException.java
deleted file mode 100644
index 0d7d1a82..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/errors/ApiMisuseException.java
+++ /dev/null
@@ -1,8 +0,0 @@
-package org.luxons.sevenwonders.errors;
-
-public class ApiMisuseException extends RuntimeException {
-
-    public ApiMisuseException(String message) {
-        super(message);
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/errors/ErrorType.java b/backend/src/main/java/org/luxons/sevenwonders/errors/ErrorType.java
deleted file mode 100644
index 16a40046..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/errors/ErrorType.java
+++ /dev/null
@@ -1,8 +0,0 @@
-package org.luxons.sevenwonders.errors;
-
-enum ErrorType {
-    USER_INPUT,
-    VALIDATION,
-    CLIENT,
-    SERVER
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/errors/ExceptionHandler.java b/backend/src/main/java/org/luxons/sevenwonders/errors/ExceptionHandler.java
deleted file mode 100644
index 628da4f8..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/errors/ExceptionHandler.java
+++ /dev/null
@@ -1,81 +0,0 @@
-package org.luxons.sevenwonders.errors;
-
-import java.util.List;
-import java.util.Locale;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.context.MessageSource;
-import org.springframework.messaging.converter.MessageConversionException;
-import org.springframework.messaging.handler.annotation.MessageExceptionHandler;
-import org.springframework.messaging.handler.annotation.support.MethodArgumentNotValidException;
-import org.springframework.messaging.simp.annotation.SendToUser;
-import org.springframework.validation.BindingResult;
-import org.springframework.validation.ObjectError;
-import org.springframework.web.bind.annotation.ControllerAdvice;
-
-@ControllerAdvice
-public class ExceptionHandler {
-
-    private static final Logger logger = LoggerFactory.getLogger(ExceptionHandler.class);
-
-    private static final String ERROR_CODE_VALIDATION = "INVALID_DATA";
-
-    private static final String ERROR_CODE_CONVERSION = "INVALID_MESSAGE_FORMAT";
-
-    private static final String ERROR_MSG_VALIDATION = "Invalid input data";
-
-    private static final String ERROR_MSG_CONVERSION = "Invalid input format";
-
-    private final MessageSource messageSource;
-
-    @Autowired
-    public ExceptionHandler(MessageSource messageSource) {
-        this.messageSource = messageSource;
-    }
-
-    @MessageExceptionHandler
-    @SendToUser("/queue/errors")
-    public UIError handleUserInputError(UserInputException exception) {
-        logger.error("Incorrect user input: " + exception.getMessage());
-        String messageKey = exception.getMessageResourceKey();
-        String message = messageSource.getMessage(messageKey, exception.getParams(), messageKey, Locale.US);
-        return new UIError(messageKey, message, ErrorType.USER_INPUT);
-    }
-
-    @MessageExceptionHandler
-    @SendToUser("/queue/errors")
-    public UIError handleValidationError(MethodArgumentNotValidException exception) {
-        logger.error("Invalid input", exception);
-        UIError uiError = new UIError(ERROR_CODE_VALIDATION, ERROR_MSG_VALIDATION, ErrorType.VALIDATION);
-
-        BindingResult result = exception.getBindingResult();
-        if (result != null) {
-            List<ObjectError> errors = result.getAllErrors();
-            uiError.addDetails(errors);
-        }
-        return uiError;
-    }
-
-    @MessageExceptionHandler
-    @SendToUser("/queue/errors")
-    public UIError handleConversionError(MessageConversionException exception) {
-        logger.error("Error interpreting the message", exception);
-        return new UIError(ERROR_CODE_CONVERSION, ERROR_MSG_CONVERSION, ErrorType.VALIDATION);
-    }
-
-    @MessageExceptionHandler
-    @SendToUser("/queue/errors")
-    public UIError handleApiError(ApiMisuseException exception) {
-        logger.error("Invalid API input", exception);
-        return new UIError(exception.getClass().getSimpleName(), exception.getMessage(), ErrorType.CLIENT);
-    }
-
-    @MessageExceptionHandler
-    @SendToUser("/queue/errors")
-    public UIError handleUnexpectedInternalError(Throwable exception) {
-        logger.error("Uncaught exception thrown during message handling", exception);
-        return new UIError(exception.getClass().getSimpleName(), exception.getMessage(), ErrorType.SERVER);
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/errors/UIError.java b/backend/src/main/java/org/luxons/sevenwonders/errors/UIError.java
deleted file mode 100644
index fbc1ee1d..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/errors/UIError.java
+++ /dev/null
@@ -1,54 +0,0 @@
-package org.luxons.sevenwonders.errors;
-
-import java.util.ArrayList;
-import java.util.List;
-
-import org.springframework.validation.FieldError;
-import org.springframework.validation.ObjectError;
-
-public class UIError {
-
-    private final String code;
-
-    private final String message;
-
-    private final ErrorType type;
-
-    private List<UIErrorDetail> details = new ArrayList<>();
-
-    UIError(String code, String message, ErrorType type) {
-        this.code = code;
-        this.message = message;
-        this.type = type;
-    }
-
-    public String getCode() {
-        return code;
-    }
-
-    public String getMessage() {
-        return message;
-    }
-
-    public ErrorType getType() {
-        return type;
-    }
-
-    public List<UIErrorDetail> getDetails() {
-        return details;
-    }
-
-    void addDetails(List<ObjectError> objectErrors) {
-        for (ObjectError objectError : objectErrors) {
-            this.details.add(convertError(objectError));
-        }
-    }
-
-    private UIErrorDetail convertError(ObjectError objectError) {
-        if (objectError instanceof FieldError) {
-            return new UIErrorDetail((FieldError) objectError);
-        } else {
-            return new UIErrorDetail(objectError);
-        }
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/errors/UIErrorDetail.java b/backend/src/main/java/org/luxons/sevenwonders/errors/UIErrorDetail.java
deleted file mode 100644
index dc4250bb..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/errors/UIErrorDetail.java
+++ /dev/null
@@ -1,37 +0,0 @@
-package org.luxons.sevenwonders.errors;
-
-import org.springframework.validation.FieldError;
-import org.springframework.validation.ObjectError;
-
-class UIErrorDetail {
-
-    private final Object rejectedValue;
-
-    private final String path;
-
-    private final String message;
-
-    UIErrorDetail(FieldError error) {
-        rejectedValue = error.getRejectedValue();
-        path = error.getObjectName() + '.' + error.getField();
-        message = "Invalid value for field '" + error.getField() + "': " + error.getDefaultMessage();
-    }
-
-    UIErrorDetail(ObjectError error) {
-        rejectedValue = null;
-        path = error.getObjectName();
-        message = "Invalid value for object '" + error.getObjectName() + "': " + error.getDefaultMessage();
-    }
-
-    public Object getRejectedValue() {
-        return rejectedValue;
-    }
-
-    public String getPath() {
-        return path;
-    }
-
-    public String getMessage() {
-        return message;
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/errors/UserInputException.java b/backend/src/main/java/org/luxons/sevenwonders/errors/UserInputException.java
deleted file mode 100644
index 4033a696..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/errors/UserInputException.java
+++ /dev/null
@@ -1,21 +0,0 @@
-package org.luxons.sevenwonders.errors;
-
-public class UserInputException extends RuntimeException {
-
-    private final String messageResourceKey;
-
-    private final Object[] params;
-
-    public UserInputException(String messageResourceKey, Object... params) {
-        this.messageResourceKey = messageResourceKey;
-        this.params = params;
-    }
-
-    String getMessageResourceKey() {
-        return messageResourceKey;
-    }
-
-    Object[] getParams() {
-        return params;
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/lobby/Lobby.java b/backend/src/main/java/org/luxons/sevenwonders/lobby/Lobby.java
deleted file mode 100644
index 1ddde0d7..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/lobby/Lobby.java
+++ /dev/null
@@ -1,168 +0,0 @@
-package org.luxons.sevenwonders.lobby;
-
-import java.util.ArrayList;
-import java.util.List;
-
-import org.luxons.sevenwonders.game.Game;
-import org.luxons.sevenwonders.game.api.CustomizableSettings;
-import org.luxons.sevenwonders.game.data.GameDefinition;
-
-public class Lobby {
-
-    private final long id;
-
-    private final String name;
-
-    private final Player owner;
-
-    private final transient GameDefinition gameDefinition;
-
-    private final List<Player> players;
-
-    private CustomizableSettings settings;
-
-    private State state = State.LOBBY;
-
-    public Lobby(long id, String name, Player owner, GameDefinition gameDefinition) {
-        this.id = id;
-        this.name = name;
-        this.owner = owner;
-        this.gameDefinition = gameDefinition;
-        this.players = new ArrayList<>(gameDefinition.getMinPlayers());
-        this.settings = new CustomizableSettings();
-        addPlayer(owner);
-    }
-
-    public long getId() {
-        return id;
-    }
-
-    public String getName() {
-        return name;
-    }
-
-    public String getOwner() {
-        return owner.getUsername();
-    }
-
-    public List<Player> getPlayers() {
-        return players;
-    }
-
-    public CustomizableSettings getSettings() {
-        return settings;
-    }
-
-    public void setSettings(CustomizableSettings settings) {
-        this.settings = settings;
-    }
-
-    public State getState() {
-        return state;
-    }
-
-    public synchronized void addPlayer(Player player) throws GameAlreadyStartedException, PlayerOverflowException {
-        if (hasStarted()) {
-            throw new GameAlreadyStartedException(name);
-        }
-        if (maxPlayersReached()) {
-            throw new PlayerOverflowException(gameDefinition.getMaxPlayers());
-        }
-        if (playerNameAlreadyUsed(player.getDisplayName())) {
-            throw new PlayerNameAlreadyUsedException(player.getDisplayName(), name);
-        }
-        player.setIndex(players.size());
-        player.setLobby(this);
-        players.add(player);
-    }
-
-    private boolean hasStarted() {
-        return state != State.LOBBY;
-    }
-
-    private boolean maxPlayersReached() {
-        return players.size() >= gameDefinition.getMaxPlayers();
-    }
-
-    private boolean playerNameAlreadyUsed(String name) {
-        return players.stream().anyMatch(p -> p.getDisplayName().equals(name));
-    }
-
-    public synchronized Game startGame() throws PlayerUnderflowException {
-        if (!hasEnoughPlayers()) {
-            throw new PlayerUnderflowException(gameDefinition.getMinPlayers());
-        }
-        state = State.PLAYING;
-        Game game = gameDefinition.initGame(id, settings, players.size());
-        players.forEach(p -> p.setGame(game));
-        return game;
-    }
-
-    private boolean hasEnoughPlayers() {
-        return players.size() >= gameDefinition.getMinPlayers();
-    }
-
-    public void reorderPlayers(List<String> orderedUsernames) throws UnknownPlayerException {
-        List<Player> formerList = new ArrayList<>(players);
-        players.clear();
-        for (int i = 0; i < orderedUsernames.size(); i++) {
-            Player player = getPlayer(formerList, orderedUsernames.get(i));
-            players.add(player);
-            player.setIndex(i);
-        }
-    }
-
-    private static Player getPlayer(List<Player> players, String username) throws UnknownPlayerException {
-        return players.stream()
-                      .filter(p -> p.getUsername().equals(username))
-                      .findAny()
-                      .orElseThrow(() -> new UnknownPlayerException(username));
-    }
-
-    public boolean isOwner(String username) {
-        return owner.getUsername().equals(username);
-    }
-
-    public boolean containsUser(String username) {
-        return players.stream().anyMatch(p -> p.getUsername().equals(username));
-    }
-
-    public Player removePlayer(String username) throws UnknownPlayerException {
-        Player player = getPlayer(players, username);
-        players.remove(player);
-        player.setIndex(-1);
-        player.setLobby(null);
-        player.setGame(null);
-        return player;
-    }
-
-    static class GameAlreadyStartedException extends IllegalStateException {
-        GameAlreadyStartedException(String name) {
-            super(String.format("Game '%s' has already started", name));
-        }
-    }
-
-    static class PlayerOverflowException extends IllegalStateException {
-        PlayerOverflowException(int max) {
-            super(String.format("Maximum %d players allowed", max));
-        }
-    }
-
-    static class PlayerUnderflowException extends IllegalStateException {
-        PlayerUnderflowException(int min) {
-            super(String.format("Minimum %d players required to start a game", min));
-        }
-    }
-
-    static class PlayerNameAlreadyUsedException extends IllegalStateException {
-        PlayerNameAlreadyUsedException(String displayName, String gameName) {
-            super(String.format("Name '%s' is already used by a player in game '%s'", displayName, gameName));
-        }
-    }
-
-    static class UnknownPlayerException extends IllegalStateException {
-        UnknownPlayerException(String username) {
-            super(String.format("Unknown player '%s'", username));
-        }
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/lobby/Player.java b/backend/src/main/java/org/luxons/sevenwonders/lobby/Player.java
deleted file mode 100644
index 496e1e67..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/lobby/Player.java
+++ /dev/null
@@ -1,76 +0,0 @@
-package org.luxons.sevenwonders.lobby;
-
-import org.luxons.sevenwonders.game.Game;
-
-import com.fasterxml.jackson.annotation.JsonIgnore;
-
-public class Player {
-
-    private final String username;
-
-    private String displayName;
-
-    private int index;
-
-    private boolean ready;
-
-    private transient Lobby lobby;
-
-    private transient Game game;
-
-    public Player(String username, String displayName) {
-        this.username = username;
-        this.displayName = displayName;
-    }
-
-    public String getUsername() {
-        return username;
-    }
-
-    public String getDisplayName() {
-        return displayName;
-    }
-
-    public void setDisplayName(String displayName) {
-        this.displayName = displayName;
-    }
-
-    public int getIndex() {
-        return index;
-    }
-
-    public void setIndex(int index) {
-        this.index = index;
-    }
-
-    public boolean isReady() {
-        return ready;
-    }
-
-    public void setReady(boolean ready) {
-        this.ready = ready;
-    }
-
-    @JsonIgnore
-    public Lobby getLobby() {
-        return lobby;
-    }
-
-    public void setLobby(Lobby lobby) {
-        this.lobby = lobby;
-    }
-
-    @JsonIgnore
-    public Game getGame() {
-        return game;
-    }
-
-    public void setGame(Game game) {
-        this.game = game;
-    }
-
-    @Override
-    public String toString() {
-        return "'" + displayName + "' (" + username + ")";
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/lobby/State.java b/backend/src/main/java/org/luxons/sevenwonders/lobby/State.java
deleted file mode 100644
index 17f3b101..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/lobby/State.java
+++ /dev/null
@@ -1,6 +0,0 @@
-package org.luxons.sevenwonders.lobby;
-
-public enum State {
-    LOBBY,
-    PLAYING
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/output/PreparedCard.java b/backend/src/main/java/org/luxons/sevenwonders/output/PreparedCard.java
deleted file mode 100644
index 5a122274..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/output/PreparedCard.java
+++ /dev/null
@@ -1,24 +0,0 @@
-package org.luxons.sevenwonders.output;
-
-import org.luxons.sevenwonders.game.cards.CardBack;
-import org.luxons.sevenwonders.lobby.Player;
-
-public class PreparedCard {
-
-    private final Player player;
-
-    private final CardBack cardBack;
-
-    public PreparedCard(Player player, CardBack cardBack) {
-        this.player = player;
-        this.cardBack = cardBack;
-    }
-
-    public Player getPlayer() {
-        return player;
-    }
-
-    public CardBack getCardBack() {
-        return cardBack;
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/repositories/LobbyRepository.java b/backend/src/main/java/org/luxons/sevenwonders/repositories/LobbyRepository.java
deleted file mode 100644
index b1b11c82..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/repositories/LobbyRepository.java
+++ /dev/null
@@ -1,59 +0,0 @@
-package org.luxons.sevenwonders.repositories;
-
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.Map;
-
-import org.luxons.sevenwonders.game.data.GameDefinitionLoader;
-import org.luxons.sevenwonders.lobby.Lobby;
-import org.luxons.sevenwonders.lobby.Player;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.stereotype.Repository;
-
-@Repository
-public class LobbyRepository {
-
-    private final GameDefinitionLoader gameDefinitionLoader;
-
-    private Map<Long, Lobby> lobbies = new HashMap<>();
-
-    private long lastGameId = 0;
-
-    @Autowired
-    public LobbyRepository() {
-        this.gameDefinitionLoader = new GameDefinitionLoader();
-    }
-
-    public Collection<Lobby> list() {
-        return lobbies.values();
-    }
-
-    public Lobby create(String gameName, Player owner) {
-        long id = lastGameId++;
-        Lobby lobby = new Lobby(id, gameName, owner, gameDefinitionLoader.getGameDefinition());
-        lobbies.put(id, lobby);
-        return lobby;
-    }
-
-    public Lobby find(long lobbyId) throws LobbyNotFoundException {
-        Lobby lobby = lobbies.get(lobbyId);
-        if (lobby == null) {
-            throw new LobbyNotFoundException(lobbyId);
-        }
-        return lobby;
-    }
-
-    public Lobby remove(long lobbyId) throws LobbyNotFoundException {
-        Lobby lobby = lobbies.remove(lobbyId);
-        if (lobby == null) {
-            throw new LobbyNotFoundException(lobbyId);
-        }
-        return lobby;
-    }
-
-    public static class LobbyNotFoundException extends RuntimeException {
-        LobbyNotFoundException(long id) {
-            super("Lobby not found for id '" + id + "'");
-        }
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/repositories/PlayerRepository.java b/backend/src/main/java/org/luxons/sevenwonders/repositories/PlayerRepository.java
deleted file mode 100644
index 62c827db..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/repositories/PlayerRepository.java
+++ /dev/null
@@ -1,60 +0,0 @@
-package org.luxons.sevenwonders.repositories;
-
-import java.util.HashMap;
-import java.util.Map;
-
-import org.luxons.sevenwonders.errors.ApiMisuseException;
-import org.luxons.sevenwonders.lobby.Player;
-import org.springframework.stereotype.Repository;
-
-@Repository
-public class PlayerRepository {
-
-    private Map<String, Player> players = new HashMap<>();
-
-    public boolean contains(String username) {
-        return players.containsKey(username);
-    }
-
-    public Player createOrUpdate(String username, String displayName) {
-        if (players.containsKey(username)) {
-            return update(username, displayName);
-        } else {
-            return create(username, displayName);
-        }
-    }
-
-    private Player create(String username, String displayName) {
-        Player player = new Player(username, displayName);
-        players.put(username, player);
-        return player;
-    }
-
-    private Player update(String username, String displayName) throws PlayerNotFoundException {
-        Player player = find(username);
-        player.setDisplayName(displayName);
-        return player;
-    }
-
-    public Player find(String username) throws PlayerNotFoundException {
-        Player player = players.get(username);
-        if (player == null) {
-            throw new PlayerNotFoundException(username);
-        }
-        return player;
-    }
-
-    public Player remove(String username) {
-        Player player = players.remove(username);
-        if (player == null) {
-            throw new PlayerNotFoundException(username);
-        }
-        return player;
-    }
-
-    public static class PlayerNotFoundException extends ApiMisuseException {
-        PlayerNotFoundException(String username) {
-            super("Player '" + username + "' doesn't exist");
-        }
-    }
-}
diff --git a/backend/src/main/java/org/luxons/sevenwonders/validation/DestinationAccessValidator.java b/backend/src/main/java/org/luxons/sevenwonders/validation/DestinationAccessValidator.java
deleted file mode 100644
index cd17b0a5..00000000
--- a/backend/src/main/java/org/luxons/sevenwonders/validation/DestinationAccessValidator.java
+++ /dev/null
@@ -1,66 +0,0 @@
-package org.luxons.sevenwonders.validation;
-
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
-
-import org.luxons.sevenwonders.lobby.Lobby;
-import org.luxons.sevenwonders.repositories.LobbyRepository;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.stereotype.Component;
-
-@Component
-public class DestinationAccessValidator {
-
-    private static final Pattern lobbyDestination = Pattern.compile(".*?/lobby/(?<id>\\d+?)(/.*)?");
-
-    private static final Pattern gameDestination = Pattern.compile(".*?/game/(?<id>\\d+?)(/.*)?");
-
-    private final LobbyRepository lobbyRepository;
-
-    @Autowired
-    public DestinationAccessValidator(LobbyRepository lobbyRepository) {
-        this.lobbyRepository = lobbyRepository;
-    }
-
-    public boolean hasAccess(String username, String destination) {
-        if (username == null) {
-            // unnamed user cannot belong to anything
-            return false;
-        }
-        if (hasForbiddenGameReference(username, destination)) {
-            return false;
-        }
-        if (hasForbiddenLobbyReference(username, destination)) {
-            return false;
-        }
-        return true;
-    }
-
-    private boolean hasForbiddenGameReference(String username, String destination) {
-        Matcher gameMatcher = gameDestination.matcher(destination);
-        if (!gameMatcher.matches()) {
-            return false; // no game reference is always OK
-        }
-        int gameId = extractId(gameMatcher);
-        return !isUserInLobby(username, gameId);
-    }
-
-    private boolean hasForbiddenLobbyReference(String username, String destination) {
-        Matcher lobbyMatcher = lobbyDestination.matcher(destination);
-        if (!lobbyMatcher.matches()) {
-            return false; // no lobby reference is always OK
-        }
-        int lobbyId = extractId(lobbyMatcher);
-        return !isUserInLobby(username, lobbyId);
-    }
-
-    private boolean isUserInLobby(String username, int lobbyId) {
-        Lobby lobby = lobbyRepository.find(lobbyId);
-        return lobby.containsUser(username);
-    }
-
-    private static int extractId(Matcher matcher) {
-        String id = matcher.group("id");
-        return Integer.parseInt(id);
-    }
-}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/SevenWonders.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/SevenWonders.kt
new file mode 100644
index 00000000..04f03956
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/SevenWonders.kt
@@ -0,0 +1,13 @@
+package org.luxons.sevenwonders
+
+import org.hildan.livedoc.spring.boot.starter.EnableJSONDoc
+import org.springframework.boot.autoconfigure.SpringBootApplication
+import org.springframework.boot.runApplication
+
+@SpringBootApplication
+@EnableJSONDoc
+class SevenWonders
+
+fun main(args: Array<String>) {
+    runApplication<SevenWonders>(*args)
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/actions/ChooseNameAction.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/ChooseNameAction.kt
new file mode 100644
index 00000000..ab444780
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/ChooseNameAction.kt
@@ -0,0 +1,19 @@
+package org.luxons.sevenwonders.actions
+
+import org.hildan.livedoc.core.annotations.types.ApiType
+import org.hildan.livedoc.core.annotations.types.ApiTypeProperty
+import org.luxons.sevenwonders.doc.Documentation
+import javax.validation.constraints.Size
+
+/**
+ * The action to choose the player's name. This is the first action that should be called.
+ */
+@ApiType(group = Documentation.GROUP_ACTIONS)
+class ChooseNameAction(
+    /**
+     * The display name of the player. May contain spaces and special characters.
+     */
+    @Size(min = 2, max = 20)
+    @ApiTypeProperty(required = true)
+    val playerName: String
+)
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/actions/CreateGameAction.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/CreateGameAction.kt
new file mode 100644
index 00000000..fbe598f2
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/CreateGameAction.kt
@@ -0,0 +1,21 @@
+package org.luxons.sevenwonders.actions
+
+import org.hildan.livedoc.core.annotations.types.ApiType
+import org.hildan.livedoc.core.annotations.types.ApiTypeProperty
+import org.luxons.sevenwonders.doc.Documentation
+import javax.validation.constraints.Size
+
+/**
+ * The action to create a game.
+ */
+@ApiType(group = Documentation.GROUP_ACTIONS)
+class CreateGameAction(
+    /**
+     * The name of the game to create.
+     */
+    @Size(min = 2, max = 30)
+    @ApiTypeProperty(required = true)
+    val gameName: String
+)
+
+
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/actions/JoinGameAction.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/JoinGameAction.kt
new file mode 100644
index 00000000..002309b3
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/JoinGameAction.kt
@@ -0,0 +1,17 @@
+package org.luxons.sevenwonders.actions
+
+import org.hildan.livedoc.core.annotations.types.ApiType
+import org.hildan.livedoc.core.annotations.types.ApiTypeProperty
+import org.luxons.sevenwonders.doc.Documentation
+
+/**
+ * The action to join a game.
+ */
+@ApiType(group = Documentation.GROUP_ACTIONS)
+class JoinGameAction(
+    /**
+     * The ID of the game to join.
+     */
+    @ApiTypeProperty(required = true)
+    val gameId: Long
+)
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/actions/PrepareMoveAction.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/PrepareMoveAction.kt
new file mode 100644
index 00000000..6b39c486
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/PrepareMoveAction.kt
@@ -0,0 +1,18 @@
+package org.luxons.sevenwonders.actions
+
+import org.hildan.livedoc.core.annotations.types.ApiType
+import org.hildan.livedoc.core.annotations.types.ApiTypeProperty
+import org.luxons.sevenwonders.doc.Documentation
+import org.luxons.sevenwonders.game.api.PlayerMove
+
+/**
+ * The action to prepare the next move during a game.
+ */
+@ApiType(group = Documentation.GROUP_ACTIONS)
+class PrepareMoveAction(
+    /**
+     * The move to prepare.
+     */
+    @ApiTypeProperty(required = true)
+    val move: PlayerMove
+)
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/actions/ReorderPlayersAction.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/ReorderPlayersAction.kt
new file mode 100644
index 00000000..79a32137
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/ReorderPlayersAction.kt
@@ -0,0 +1,18 @@
+package org.luxons.sevenwonders.actions
+
+import org.hildan.livedoc.core.annotations.types.ApiType
+import org.hildan.livedoc.core.annotations.types.ApiTypeProperty
+import org.luxons.sevenwonders.doc.Documentation
+
+/**
+ * The action to update the order of the players around the table. Can only be called in the lobby by the owner of the
+ * game.
+ */
+@ApiType(group = Documentation.GROUP_ACTIONS)
+class ReorderPlayersAction(
+    /**
+     * The list of usernames of the players, in the new order.
+     */
+    @ApiTypeProperty(required = true)
+    val orderedPlayers: List<String>
+)
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/actions/UpdateSettingsAction.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/UpdateSettingsAction.kt
new file mode 100644
index 00000000..d13e5b45
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/actions/UpdateSettingsAction.kt
@@ -0,0 +1,18 @@
+package org.luxons.sevenwonders.actions
+
+import org.hildan.livedoc.core.annotations.types.ApiType
+import org.hildan.livedoc.core.annotations.types.ApiTypeProperty
+import org.luxons.sevenwonders.doc.Documentation
+import org.luxons.sevenwonders.game.api.CustomizableSettings
+
+/**
+ * The action to update the settings of the game. Can only be called in the lobby by the owner of the game.
+ */
+@ApiType(group = Documentation.GROUP_ACTIONS)
+class UpdateSettingsAction(
+    /**
+     * The new values for the settings.
+     */
+    @ApiTypeProperty(required = true)
+    val settings: CustomizableSettings
+)
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/config/AnonymousUsersHandshakeHandler.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/config/AnonymousUsersHandshakeHandler.kt
new file mode 100644
index 00000000..db707d1b
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/config/AnonymousUsersHandshakeHandler.kt
@@ -0,0 +1,27 @@
+package org.luxons.sevenwonders.config
+
+import org.springframework.http.server.ServerHttpRequest
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken
+import org.springframework.web.socket.WebSocketHandler
+import org.springframework.web.socket.server.support.DefaultHandshakeHandler
+import java.security.Principal
+
+/**
+ * Generates [Principal] objects for anonymous users in the form "playerX", where X is an auto-incremented number.
+ */
+internal class AnonymousUsersHandshakeHandler : DefaultHandshakeHandler() {
+
+    private var playerId = 0
+
+    override fun determineUser(
+        request: ServerHttpRequest,
+        wsHandler: WebSocketHandler,
+        attributes: Map<String, Any>
+    ): Principal? {
+        var p = super.determineUser(request, wsHandler, attributes)
+        if (p == null) {
+            p = UsernamePasswordAuthenticationToken("player" + playerId++, null)
+        }
+        return p
+    }
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/config/TopicSubscriptionInterceptor.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/config/TopicSubscriptionInterceptor.kt
new file mode 100644
index 00000000..f4c55c2c
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/config/TopicSubscriptionInterceptor.kt
@@ -0,0 +1,38 @@
+package org.luxons.sevenwonders.config
+
+import org.luxons.sevenwonders.validation.DestinationAccessValidator
+import org.slf4j.LoggerFactory
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.messaging.Message
+import org.springframework.messaging.MessageChannel
+import org.springframework.messaging.simp.stomp.StompCommand
+import org.springframework.messaging.simp.stomp.StompHeaderAccessor
+import org.springframework.messaging.support.ChannelInterceptor
+import org.springframework.stereotype.Component
+
+@Component
+class TopicSubscriptionInterceptor @Autowired constructor(
+    private val destinationAccessValidator: DestinationAccessValidator
+) : ChannelInterceptor {
+
+    override fun preSend(message: Message<*>, channel: MessageChannel): Message<*>? {
+        val headerAccessor = StompHeaderAccessor.wrap(message)
+        if (StompCommand.SUBSCRIBE == headerAccessor.command) {
+            val username = headerAccessor.user!!.name
+            val destination = headerAccessor.destination!!
+            if (!destinationAccessValidator.hasAccess(username, destination)) {
+                sendForbiddenSubscriptionError(username, destination)
+                return null
+            }
+        }
+        return message
+    }
+
+    private fun sendForbiddenSubscriptionError(username: String, destination: String?) {
+        logger.error(String.format("Player '%s' is not allowed to access %s", username, destination))
+    }
+
+    companion object {
+        private val logger = LoggerFactory.getLogger(TopicSubscriptionInterceptor::class.java)
+    }
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/config/WebSecurityConfig.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/config/WebSecurityConfig.kt
new file mode 100644
index 00000000..06b2bc90
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/config/WebSecurityConfig.kt
@@ -0,0 +1,12 @@
+package org.luxons.sevenwonders.config
+
+import org.springframework.context.annotation.Configuration
+import org.springframework.security.config.annotation.web.builders.HttpSecurity
+import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter
+
+@Configuration
+class WebSecurityConfig : WebSecurityConfigurerAdapter() {
+
+    // this disables default authentication settings
+    override fun configure(httpSecurity: HttpSecurity) = Unit
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/config/WebSocketConfig.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/config/WebSocketConfig.kt
new file mode 100644
index 00000000..bebb3233
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/config/WebSocketConfig.kt
@@ -0,0 +1,42 @@
+package org.luxons.sevenwonders.config
+
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.context.annotation.Bean
+import org.springframework.context.annotation.Configuration
+import org.springframework.messaging.simp.config.ChannelRegistration
+import org.springframework.messaging.simp.config.MessageBrokerRegistry
+import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker
+import org.springframework.web.socket.config.annotation.StompEndpointRegistry
+import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer
+import org.springframework.web.socket.server.support.DefaultHandshakeHandler
+
+@Configuration
+@EnableWebSocketMessageBroker
+class WebSocketConfig @Autowired constructor(private val topicSubscriptionInterceptor: TopicSubscriptionInterceptor) :
+    WebSocketMessageBrokerConfigurer {
+
+    override fun configureMessageBroker(config: MessageBrokerRegistry) {
+        // prefixes for all subscriptions
+        config.enableSimpleBroker("/queue", "/topic")
+        config.setUserDestinationPrefix("/user")
+
+        // /app for normal calls, /topic for subscription events
+        config.setApplicationDestinationPrefixes("/app", "/topic")
+    }
+
+    override fun registerStompEndpoints(registry: StompEndpointRegistry) {
+        registry.addEndpoint("/seven-wonders-websocket")
+            .setHandshakeHandler(handshakeHandler())
+            .setAllowedOrigins("http://localhost:3000") // to allow frontend server proxy requests in dev mode
+            .withSockJS()
+    }
+
+    @Bean
+    fun handshakeHandler(): DefaultHandshakeHandler {
+        return AnonymousUsersHandshakeHandler()
+    }
+
+    override fun configureClientInboundChannel(registration: ChannelRegistration) {
+        registration.interceptors(topicSubscriptionInterceptor)
+    }
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/GameBrowserController.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/GameBrowserController.kt
new file mode 100644
index 00000000..b8e4e732
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/GameBrowserController.kt
@@ -0,0 +1,109 @@
+package org.luxons.sevenwonders.controllers
+
+import org.hildan.livedoc.core.annotations.Api
+import org.luxons.sevenwonders.actions.CreateGameAction
+import org.luxons.sevenwonders.actions.JoinGameAction
+import org.luxons.sevenwonders.errors.ApiMisuseException
+import org.luxons.sevenwonders.lobby.Lobby
+import org.luxons.sevenwonders.repositories.LobbyRepository
+import org.luxons.sevenwonders.repositories.PlayerRepository
+import org.slf4j.LoggerFactory
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.messaging.handler.annotation.MessageMapping
+import org.springframework.messaging.simp.SimpMessagingTemplate
+import org.springframework.messaging.simp.annotation.SendToUser
+import org.springframework.messaging.simp.annotation.SubscribeMapping
+import org.springframework.stereotype.Controller
+import org.springframework.validation.annotation.Validated
+import java.security.Principal
+
+/**
+ * This is the place where the player looks for a game.
+ */
+@Api(name = "GameBrowser")
+@Controller
+class GameBrowserController @Autowired constructor(
+    private val lobbyController: LobbyController,
+    private val lobbyRepository: LobbyRepository,
+    private val playerRepository: PlayerRepository,
+    private val template: SimpMessagingTemplate
+) {
+
+    /**
+     * Gets the created or updated games. The list of existing games is received on this topic at once upon
+     * subscription, and then each time the list changes.
+     *
+     * @param principal the connected user's information
+     *
+     * @return the current list of [Lobby]s
+     */
+    @SubscribeMapping("/games") // prefix /topic not shown
+    fun listGames(principal: Principal): Collection<Lobby> {
+        logger.info("Player '{}' subscribed to /topic/games", principal.name)
+        return lobbyRepository.list()
+    }
+
+    /**
+     * Creates a new [Lobby].
+     *
+     * @param action the action to create the game
+     * @param principal the connected user's information
+     *
+     * @return the newly created [Lobby]
+     */
+    @MessageMapping("/lobby/create")
+    @SendToUser("/queue/lobby/joined")
+    fun createGame(@Validated action: CreateGameAction, principal: Principal): Lobby {
+        checkThatUserIsNotInAGame(principal, "cannot create another game")
+
+        val gameOwner = playerRepository.find(principal.name)
+        val lobby = lobbyRepository.create(action.gameName, gameOwner)
+
+        logger.info(
+            "Game '{}' ({}) created by {} ({})", lobby.name, lobby.id, gameOwner.displayName, gameOwner.username
+        )
+
+        // notify everyone that a new game exists
+        template.convertAndSend("/topic/games", listOf(lobby))
+        return lobby
+    }
+
+    /**
+     * Joins an existing [Lobby].
+     *
+     * @param action the action to join the game
+     * @param principal the connected user's information
+     *
+     * @return the [Lobby] that has just been joined
+     */
+    @MessageMapping("/lobby/join")
+    @SendToUser("/queue/lobby/joined")
+    fun joinGame(@Validated action: JoinGameAction, principal: Principal): Lobby {
+        checkThatUserIsNotInAGame(principal, "cannot join another game")
+
+        val lobby = lobbyRepository.find(action.gameId!!)
+        val newPlayer = playerRepository.find(principal.name)
+        lobby.addPlayer(newPlayer)
+
+        logger.info(
+            "Player '{}' ({}) joined game {}", newPlayer.displayName, newPlayer.username, lobby.name
+        )
+        lobbyController.sendLobbyUpdateToPlayers(lobby)
+        return lobby
+    }
+
+    private fun checkThatUserIsNotInAGame(principal: Principal, impossibleActionDescription: String) {
+        val player = playerRepository.find(principal.name)
+        if (player.isInLobby || player.isInGame) {
+            throw UserAlreadyInGameException(player.lobby.name, impossibleActionDescription)
+        }
+    }
+
+    internal class UserAlreadyInGameException(gameName: String, impossibleActionDescription: String) :
+        ApiMisuseException("Client already in game '$gameName', $impossibleActionDescription")
+
+    companion object {
+
+        private val logger = LoggerFactory.getLogger(GameBrowserController::class.java)
+    }
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/GameController.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/GameController.kt
new file mode 100644
index 00000000..e05bf319
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/GameController.kt
@@ -0,0 +1,99 @@
+package org.luxons.sevenwonders.controllers
+
+import org.hildan.livedoc.core.annotations.Api
+import org.luxons.sevenwonders.actions.PrepareMoveAction
+import org.luxons.sevenwonders.game.Game
+import org.luxons.sevenwonders.game.api.Table
+import org.luxons.sevenwonders.lobby.Player
+import org.luxons.sevenwonders.output.PreparedCard
+import org.luxons.sevenwonders.repositories.PlayerRepository
+import org.slf4j.LoggerFactory
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.messaging.handler.annotation.MessageMapping
+import org.springframework.messaging.simp.SimpMessagingTemplate
+import org.springframework.stereotype.Controller
+import java.security.Principal
+
+/**
+ * This API is for in-game events management.
+ */
+@Api(name = "Game")
+@Controller
+class GameController @Autowired constructor(
+    private val template: SimpMessagingTemplate,
+    private val playerRepository: PlayerRepository
+) {
+    private val Principal.player
+        get() = playerRepository.find(name)
+
+    /**
+     * Notifies the game that the player is ready to receive his hand.
+     *
+     * @param principal
+     * the connected user's information
+     */
+    @MessageMapping("/game/sayReady")
+    fun ready(principal: Principal) {
+        val player = principal.player
+        player.isReady = true
+        val game = player.game
+        logger.info("Game {}: player {} is ready for the next turn", game.id, player)
+
+        val lobby = player.lobby
+        val players = lobby.getPlayers()
+
+        val allReady = players.stream().allMatch { it.isReady }
+        if (allReady) {
+            logger.info("Game {}: all players ready, sending turn info", game.id)
+            players.forEach { it.isReady = false }
+            sendTurnInfo(players, game)
+        } else {
+            sendPlayerReady(game.id, player)
+        }
+    }
+
+    private fun sendTurnInfo(players: List<Player>, game: Game) {
+        for (turnInfo in game.getCurrentTurnInfo()) {
+            val player = players[turnInfo.playerIndex]
+            template.convertAndSendToUser(player.username, "/queue/game/turn", turnInfo)
+        }
+    }
+
+    private fun sendPlayerReady(gameId: Long, player: Player) =
+        template.convertAndSend("/topic/game/$gameId/playerReady", player.username)
+
+    /**
+     * Prepares the player's next move. When all players have prepared their moves, all moves are executed.
+     *
+     * @param action
+     * the action to prepare the move
+     * @param principal
+     * the connected user's information
+     */
+    @MessageMapping("/game/prepareMove")
+    fun prepareMove(action: PrepareMoveAction, principal: Principal) {
+        val player = principal.player
+        val game = player.game
+        val preparedCardBack = game.prepareMove(player.index, action.move)
+        val preparedCard = PreparedCard(player, preparedCardBack)
+        logger.info("Game {}: player {} prepared move {}", game.id, principal.name, action.move)
+
+        if (game.allPlayersPreparedTheirMove()) {
+            logger.info("Game {}: all players have prepared their move, executing turn...", game.id)
+            val table = game.playTurn()
+            sendPlayedMoves(game.id, table)
+        } else {
+            sendPreparedCard(game.id, preparedCard)
+        }
+    }
+
+    private fun sendPlayedMoves(gameId: Long, table: Table) =
+        template.convertAndSend("/topic/game/$gameId/tableUpdates", table)
+
+    private fun sendPreparedCard(gameId: Long, preparedCard: PreparedCard) =
+        template.convertAndSend("/topic/game/$gameId/prepared", preparedCard)
+
+    companion object {
+        private val logger = LoggerFactory.getLogger(GameController::class.java)
+    }
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/HomeController.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/HomeController.kt
new file mode 100644
index 00000000..e658a26b
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/HomeController.kt
@@ -0,0 +1,47 @@
+package org.luxons.sevenwonders.controllers
+
+import org.hildan.livedoc.core.annotations.Api
+import org.luxons.sevenwonders.actions.ChooseNameAction
+import org.luxons.sevenwonders.lobby.Player
+import org.luxons.sevenwonders.repositories.PlayerRepository
+import org.slf4j.LoggerFactory
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.messaging.handler.annotation.MessageMapping
+import org.springframework.messaging.simp.annotation.SendToUser
+import org.springframework.stereotype.Controller
+import org.springframework.validation.annotation.Validated
+import java.security.Principal
+
+/**
+ * Handles actions in the homepage of the game.
+ */
+@Api(name = "Home")
+@Controller
+class HomeController @Autowired constructor(
+    private val playerRepository: PlayerRepository
+) {
+
+    /**
+     * Creates/updates the player's name (for the user's session).
+     *
+     * @param action
+     * the action to choose the name of the player
+     * @param principal
+     * the connected user's information
+     *
+     * @return the created [Player] object
+     */
+    @MessageMapping("/chooseName")
+    @SendToUser("/queue/nameChoice")
+    fun chooseName(@Validated action: ChooseNameAction, principal: Principal): Player {
+        val username = principal.name
+        val player = playerRepository.createOrUpdate(username, action.playerName)
+
+        logger.info("Player '{}' chose the name '{}'", username, player.displayName)
+        return player
+    }
+
+    companion object {
+        private val logger = LoggerFactory.getLogger(HomeController::class.java)
+    }
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/LobbyController.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/LobbyController.kt
new file mode 100644
index 00000000..3b15d68a
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/controllers/LobbyController.kt
@@ -0,0 +1,106 @@
+package org.luxons.sevenwonders.controllers
+
+import org.hildan.livedoc.core.annotations.Api
+import org.luxons.sevenwonders.actions.ReorderPlayersAction
+import org.luxons.sevenwonders.actions.UpdateSettingsAction
+import org.luxons.sevenwonders.lobby.Lobby
+import org.luxons.sevenwonders.lobby.Player
+import org.luxons.sevenwonders.repositories.LobbyRepository
+import org.luxons.sevenwonders.repositories.PlayerRepository
+import org.slf4j.LoggerFactory
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.messaging.handler.annotation.MessageMapping
+import org.springframework.messaging.simp.SimpMessagingTemplate
+import org.springframework.stereotype.Controller
+import org.springframework.validation.annotation.Validated
+import java.security.Principal
+
+/**
+ * Handles actions in the game's lobby. The lobby is the place where players gather before a game.
+ */
+@Api(name = "Lobby")
+@Controller
+class LobbyController @Autowired constructor(
+    private val lobbyRepository: LobbyRepository,
+    private val playerRepository: PlayerRepository,
+    private val template: SimpMessagingTemplate
+) {
+    private val Principal.player: Player
+        get() = playerRepository.find(name)
+
+    /**
+     * Leaves the current lobby.
+     *
+     * @param principal
+     * the connected user's information
+     */
+    @MessageMapping("/lobby/leave")
+    fun leave(principal: Principal) {
+        val lobby = principal.player.lobby
+        val player = lobby.removePlayer(principal.name)
+        if (lobby.getPlayers().isEmpty()) {
+            lobbyRepository.remove(lobby.id)
+        }
+
+        logger.info("Player {} left game '{}'", player, lobby.name)
+        sendLobbyUpdateToPlayers(lobby)
+    }
+
+    /**
+     * Reorders the players in the current lobby. This can only be done by the lobby's owner.
+     *
+     * @param action
+     * the action to reorder the players
+     * @param principal
+     * the connected user's information
+     */
+    @MessageMapping("/lobby/reorderPlayers")
+    fun reorderPlayers(@Validated action: ReorderPlayersAction, principal: Principal) {
+        val lobby = principal.player.ownedLobby
+        lobby.reorderPlayers(action.orderedPlayers)
+
+        logger.info("Players in game '{}' reordered to {}", lobby.name, action.orderedPlayers)
+        sendLobbyUpdateToPlayers(lobby)
+    }
+
+    /**
+     * Updates the game settings. This can only be done by the lobby's owner.
+     *
+     * @param action
+     * the action to update the settings
+     * @param principal
+     * the connected user's information
+     */
+    @MessageMapping("/lobby/updateSettings")
+    fun updateSettings(@Validated action: UpdateSettingsAction, principal: Principal) {
+        val lobby = principal.player.ownedLobby
+        lobby.settings = action.settings
+
+        logger.info("Updated settings of game '{}'", lobby.name)
+        sendLobbyUpdateToPlayers(lobby)
+    }
+
+    internal fun sendLobbyUpdateToPlayers(lobby: Lobby) {
+        template.convertAndSend("/topic/lobby/" + lobby.id + "/updated", lobby)
+        template.convertAndSend("/topic/games", listOf(lobby))
+    }
+
+    /**
+     * Starts the game.
+     *
+     * @param principal
+     * the connected user's information
+     */
+    @MessageMapping("/lobby/startGame")
+    fun startGame(principal: Principal) {
+        val lobby = principal.player.ownedLobby
+        val game = lobby.startGame()
+
+        logger.info("Game {} successfully started", game.id)
+        template.convertAndSend("/topic/lobby/" + lobby.id + "/started", "")
+    }
+
+    companion object {
+        private val logger = LoggerFactory.getLogger(LobbyController::class.java)
+    }
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/doc/Documentation.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/doc/Documentation.kt
new file mode 100644
index 00000000..3b04356a
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/doc/Documentation.kt
@@ -0,0 +1,6 @@
+package org.luxons.sevenwonders.doc
+
+object Documentation {
+
+    const val GROUP_ACTIONS = "Actions"
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/errors/ErrorDTO.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/errors/ErrorDTO.kt
new file mode 100644
index 00000000..c3eae0b5
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/errors/ErrorDTO.kt
@@ -0,0 +1,29 @@
+package org.luxons.sevenwonders.errors
+
+import org.springframework.validation.FieldError
+import org.springframework.validation.ObjectError
+
+enum class ErrorType {
+    VALIDATION, CLIENT, SERVER
+}
+
+data class ErrorDTO(
+    val code: String,
+    val message: String,
+    val type: ErrorType,
+    val details: List<ValidationErrorDTO> = emptyList()
+)
+
+data class ValidationErrorDTO(
+    val path: String,
+    val message: String,
+    val rejectedValue: Any? = null
+)
+
+fun ObjectError.toDTO() = (this as? FieldError)?.fieldError() ?: objectError()
+
+fun FieldError.fieldError(): ValidationErrorDTO =
+    ValidationErrorDTO("$objectName.$field", "Invalid value for field '$field': $defaultMessage", rejectedValue)
+
+fun ObjectError.objectError(): ValidationErrorDTO =
+    ValidationErrorDTO(objectName, "Invalid value for object '$objectName': $defaultMessage")
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/errors/ExceptionHandler.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/errors/ExceptionHandler.kt
new file mode 100644
index 00000000..76d01f5f
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/errors/ExceptionHandler.kt
@@ -0,0 +1,44 @@
+package org.luxons.sevenwonders.errors
+
+import org.slf4j.LoggerFactory
+import org.springframework.messaging.converter.MessageConversionException
+import org.springframework.messaging.handler.annotation.MessageExceptionHandler
+import org.springframework.messaging.handler.annotation.support.MethodArgumentNotValidException
+import org.springframework.messaging.simp.annotation.SendToUser
+import org.springframework.web.bind.annotation.ControllerAdvice
+
+open class ApiMisuseException(message: String) : RuntimeException(message)
+
+@ControllerAdvice
+@SendToUser("/queue/errors")
+class ExceptionHandler {
+
+    @MessageExceptionHandler
+    fun handleValidationError(exception: MethodArgumentNotValidException): ErrorDTO {
+        logger.error("Invalid input", exception)
+        val validationErrors = exception.bindingResult?.allErrors?.map { it.toDTO() } ?: emptyList()
+        return ErrorDTO("INVALID_DATA", "Invalid input data", ErrorType.VALIDATION, validationErrors)
+    }
+
+    @MessageExceptionHandler
+    fun handleConversionError(exception: MessageConversionException): ErrorDTO {
+        logger.error("Error interpreting the message", exception)
+        return ErrorDTO("INVALID_MESSAGE_FORMAT", "Invalid input format", ErrorType.VALIDATION)
+    }
+
+    @MessageExceptionHandler
+    fun handleApiError(exception: ApiMisuseException): ErrorDTO {
+        logger.error("Invalid API input", exception)
+        return ErrorDTO(exception.javaClass.simpleName, exception.message!!, ErrorType.CLIENT)
+    }
+
+    @MessageExceptionHandler
+    fun handleUnexpectedInternalError(exception: Throwable): ErrorDTO {
+        logger.error("Uncaught exception thrown during message handling", exception)
+        return ErrorDTO(exception.javaClass.simpleName, exception.localizedMessage ?: "", ErrorType.SERVER)
+    }
+
+    companion object {
+        private val logger = LoggerFactory.getLogger(ExceptionHandler::class.java)
+    }
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/lobby/Lobby.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/lobby/Lobby.kt
new file mode 100644
index 00000000..aaafd517
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/lobby/Lobby.kt
@@ -0,0 +1,107 @@
+package org.luxons.sevenwonders.lobby
+
+import org.luxons.sevenwonders.game.Game
+import org.luxons.sevenwonders.game.api.CustomizableSettings
+import org.luxons.sevenwonders.game.data.GameDefinition
+import java.util.ArrayList
+
+enum class State {
+    LOBBY, PLAYING
+}
+
+class Lobby(
+    val id: Long,
+    val name: String,
+    private var _owner: Player,
+    @field:Transient private val gameDefinition: GameDefinition
+) {
+    private var players: MutableList<Player> = ArrayList(gameDefinition.maxPlayers)
+
+    var settings: CustomizableSettings = CustomizableSettings()
+
+    var owner = _owner.username
+
+    var state = State.LOBBY
+        private set
+
+    init {
+        addPlayer(_owner)
+    }
+
+    fun getPlayers(): List<Player> = players
+
+    @Synchronized
+    fun addPlayer(player: Player) {
+        if (hasStarted()) {
+            throw GameAlreadyStartedException(name)
+        }
+        if (maxPlayersReached()) {
+            throw PlayerOverflowException(gameDefinition.maxPlayers)
+        }
+        if (playerNameAlreadyUsed(player.displayName)) {
+            throw PlayerNameAlreadyUsedException(player.displayName, name)
+        }
+        player.join(this)
+        players.add(player)
+    }
+
+    private fun hasStarted(): Boolean = state != State.LOBBY
+
+    private fun maxPlayersReached(): Boolean = players.size >= gameDefinition.maxPlayers
+
+    private fun playerNameAlreadyUsed(name: String?): Boolean = players.any { it.displayName == name }
+
+    @Synchronized
+    fun startGame(): Game {
+        if (!hasEnoughPlayers()) {
+            throw PlayerUnderflowException(gameDefinition.minPlayers)
+        }
+        state = State.PLAYING
+        val game = gameDefinition.initGame(id, settings, players.size)
+        players.forEachIndexed { index, player -> player.join(game, index) }
+        return game
+    }
+
+    private fun hasEnoughPlayers(): Boolean = players.size >= gameDefinition.minPlayers
+
+    @Synchronized
+    fun reorderPlayers(orderedUsernames: List<String>) {
+        players = orderedUsernames.map { find(it) }.toMutableList()
+    }
+
+    private fun find(username: String): Player =
+        players.firstOrNull { it.username == username } ?: throw UnknownPlayerException(username)
+
+    @Synchronized
+    fun isOwner(username: String?): Boolean = _owner.username == username
+
+    @Synchronized
+    fun containsUser(username: String): Boolean = players.any { it.username == username }
+
+    @Synchronized
+    fun removePlayer(username: String): Player {
+        val player = find(username)
+        players.remove(player)
+        player.leave()
+
+        if (player == _owner && !players.isEmpty()) {
+            _owner = players[0]
+        }
+        return player
+    }
+
+    internal class GameAlreadyStartedException(name: String) :
+        IllegalStateException("Game '$name' has already started")
+
+    internal class PlayerOverflowException(max: Int) :
+        IllegalStateException("Maximum $max players allowed")
+
+    internal class PlayerUnderflowException(min: Int) :
+        IllegalStateException("Minimum $min players required to start a game")
+
+    internal class PlayerNameAlreadyUsedException(displayName: String, gameName: String) :
+        IllegalStateException("Name '$displayName' is already used by a player in game '$gameName'")
+
+    internal class UnknownPlayerException(username: String) :
+        IllegalStateException("Unknown player '$username'")
+}
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/lobby/Player.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/lobby/Player.kt
new file mode 100644
index 00000000..48a31047
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/lobby/Player.kt
@@ -0,0 +1,70 @@
+package org.luxons.sevenwonders.lobby
+
+import com.fasterxml.jackson.annotation.JsonIgnore
+import org.luxons.sevenwonders.errors.ApiMisuseException
+import org.luxons.sevenwonders.game.Game
+
+class Player(
+    val username: String,
+    var displayName: String
+) {
+    var index: Int = -1
+
+    var isReady: Boolean = false
+
+    val isGameOwner: Boolean
+        get() = _lobby?.isOwner(username) ?: false
+
+    val isInLobby: Boolean
+        get() = _lobby != null
+
+    val isInGame: Boolean
+        get() = _game != null
+
+    @Transient
+    private var _lobby: Lobby? = null
+
+    @get:JsonIgnore
+    val lobby: Lobby
+        get() = _lobby ?: throw PlayerNotInLobbyException(username)
+
+    @get:JsonIgnore
+    val ownedLobby: Lobby
+        get() = if (isGameOwner) lobby else throw PlayerIsNotOwnerException(username)
+
+    @Transient
+    private var _game: Game? = null
+
+    @get:JsonIgnore
+    val game: Game
+        get() = _game ?: throw PlayerNotInGameException(username)
+
+    fun join(lobby: Lobby) {
+        _lobby = lobby
+    }
+
+    fun join(game: Game, index: Int) {
+        _game = game
+        this.index = index
+    }
+
+    fun leave() {
+        _lobby = null
+        _game = null
+        index = -1
+    }
+
+    override fun toString(): String {
+        return "'$displayName' ($username)"
+    }
+}
+
+internal class PlayerNotInLobbyException(username: String) :
+    ApiMisuseException("User $username is not in a lobby, create or join a game first")
+
+internal class PlayerIsNotOwnerException(username: String) :
+    ApiMisuseException("User $username does not own the lobby he's in")
+
+internal class PlayerNotInGameException(username: String) :
+    ApiMisuseException("User $username is not in a game, start a game first")
+
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/output/PreparedCard.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/output/PreparedCard.kt
new file mode 100644
index 00000000..956b1a2c
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/output/PreparedCard.kt
@@ -0,0 +1,6 @@
+package org.luxons.sevenwonders.output
+
+import org.luxons.sevenwonders.game.cards.CardBack
+import org.luxons.sevenwonders.lobby.Player
+
+class PreparedCard(val player: Player, val cardBack: CardBack)
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/repositories/LobbyRepository.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/repositories/LobbyRepository.kt
new file mode 100644
index 00000000..261f723c
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/repositories/LobbyRepository.kt
@@ -0,0 +1,33 @@
+package org.luxons.sevenwonders.repositories
+
+import org.luxons.sevenwonders.game.data.GameDefinitionLoader
+import org.luxons.sevenwonders.lobby.Lobby
+import org.luxons.sevenwonders.lobby.Player
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.stereotype.Repository
+import java.util.HashMap
+
+@Repository
+class LobbyRepository @Autowired constructor() {
+
+    private val gameDefinitionLoader: GameDefinitionLoader = GameDefinitionLoader()
+
+    private val lobbies = HashMap<Long, Lobby>()
+
+    private var lastGameId: Long = 0
+
+    fun list(): Collection<Lobby> = lobbies.values
+
+    fun create(gameName: String, owner: Player): Lobby {
+        val id = lastGameId++
+        val lobby = Lobby(id, gameName, owner, gameDefinitionLoader.gameDefinition)
+        lobbies[id] = lobby
+        return lobby
+    }
+
+    fun find(lobbyId: Long): Lobby = lobbies[lobbyId] ?: throw LobbyNotFoundException(lobbyId)
+
+    fun remove(lobbyId: Long): Lobby = lobbies.remove(lobbyId) ?: throw LobbyNotFoundException(lobbyId)
+}
+
+internal class LobbyNotFoundException(id: Long) : RuntimeException("Lobby not found for id '$id'")
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/repositories/PlayerRepository.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/repositories/PlayerRepository.kt
new file mode 100644
index 00000000..4d552eaa
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/repositories/PlayerRepository.kt
@@ -0,0 +1,41 @@
+package org.luxons.sevenwonders.repositories
+
+import org.luxons.sevenwonders.errors.ApiMisuseException
+import org.luxons.sevenwonders.lobby.Player
+import org.springframework.stereotype.Repository
+import java.util.HashMap
+
+@Repository
+class PlayerRepository {
+
+    private val players = HashMap<String, Player>()
+
+    operator fun contains(username: String): Boolean = players.containsKey(username)
+
+    fun createOrUpdate(username: String, displayName: String): Player {
+        return if (players.containsKey(username)) {
+            update(username, displayName)
+        } else {
+            create(username, displayName)
+        }
+    }
+
+    private fun create(username: String, displayName: String): Player {
+        val player = Player(username, displayName)
+        players[username] = player
+        return player
+    }
+
+    private fun update(username: String, displayName: String): Player {
+        val player = find(username)
+        player.displayName = displayName
+        return player
+    }
+
+    fun find(username: String): Player = players[username] ?: throw PlayerNotFoundException(username)
+
+    fun remove(username: String): Player = players.remove(username) ?: throw PlayerNotFoundException(username)
+}
+
+internal class PlayerNotFoundException(username: String) :
+    ApiMisuseException("Player '$username' doesn't exist")
diff --git a/backend/src/main/kotlin/org/luxons/sevenwonders/validation/DestinationAccessValidator.kt b/backend/src/main/kotlin/org/luxons/sevenwonders/validation/DestinationAccessValidator.kt
new file mode 100644
index 00000000..5800edbb
--- /dev/null
+++ b/backend/src/main/kotlin/org/luxons/sevenwonders/validation/DestinationAccessValidator.kt
@@ -0,0 +1,55 @@
+package org.luxons.sevenwonders.validation
+
+import org.luxons.sevenwonders.repositories.LobbyRepository
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.stereotype.Component
+import java.util.regex.Matcher
+import java.util.regex.Pattern
+
+@Component
+class DestinationAccessValidator @Autowired constructor(private val lobbyRepository: LobbyRepository) {
+
+    fun hasAccess(username: String?, destination: String): Boolean {
+        return when {
+            username == null                                  -> false // unnamed user cannot belong to anything
+            hasForbiddenGameReference(username, destination)  -> false
+            hasForbiddenLobbyReference(username, destination) -> false
+            else                                              -> true
+        }
+    }
+
+    private fun hasForbiddenGameReference(username: String, destination: String): Boolean {
+        val gameMatcher = gameDestination.matcher(destination)
+        if (!gameMatcher.matches()) {
+            return false // no game reference is always OK
+        }
+        val gameId = extractId(gameMatcher)
+        return !isUserInLobby(username, gameId)
+    }
+
+    private fun hasForbiddenLobbyReference(username: String, destination: String): Boolean {
+        val lobbyMatcher = lobbyDestination.matcher(destination)
+        if (!lobbyMatcher.matches()) {
+            return false // no lobby reference is always OK
+        }
+        val lobbyId = extractId(lobbyMatcher)
+        return !isUserInLobby(username, lobbyId)
+    }
+
+    private fun isUserInLobby(username: String, lobbyId: Int): Boolean {
+        val lobby = lobbyRepository.find(lobbyId.toLong())
+        return lobby.containsUser(username)
+    }
+
+    companion object {
+
+        private val lobbyDestination = Pattern.compile(".*?/lobby/(?<id>\\d+?)(/.*)?")
+
+        private val gameDestination = Pattern.compile(".*?/game/(?<id>\\d+?)(/.*)?")
+
+        private fun extractId(matcher: Matcher): Int {
+            val id = matcher.group("id")
+            return Integer.parseInt(id)
+        }
+    }
+}