feat(board): add readable physical board signs

src/main/java/games/dmg/spigotquestboard/BoardRegistry.java

@@ -46,6 +46,10 @@ final class BoardRegistry {
         return boards.size();
     }
 
+    synchronized Map<BoardId, RegisteredBoard> registeredBoards() {
+        return Map.copyOf(boards);
+    }
+
     private static Map<BoardId, RegisteredBoard> index(BoardState state) throws IOException {
         Map<BoardId, RegisteredBoard> indexed = new LinkedHashMap<>();
         for (RegisteredBoard board : state.boards()) {

src/main/java/games/dmg/spigotquestboard/BukkitPhysicalBoardWorld.java

@@ -1,5 +1,6 @@
 package games.dmg.spigotquestboard;
 
+import java.util.List;
 import java.util.Objects;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.format.NamedTextColor;
@@ -17,6 +18,13 @@ final class BukkitPhysicalBoardWorld implements PhysicalBoardWorld {
     private static final Component DECORATIVE_TEXT = Component.text("xxxxxxxx")
         .color(NamedTextColor.DARK_GREEN)
         .decorate(TextDecoration.OBFUSCATED);
+    private static final List<Component> TITLE_TEXT = List.of(
+        Component.text("Quest"), Component.text("Board"), Component.empty(), Component.empty()
+    );
+    private static final List<Component> INSTRUCTION_TEXT = List.of(
+        Component.text("Right-click"), Component.text("a sign below"),
+        Component.text("to browse"), Component.text("quests")
+    );
     private final World world;
 
     BukkitPhysicalBoardWorld(World world) {
@@ -55,14 +63,39 @@ final class BukkitPhysicalBoardWorld implements PhysicalBoardWorld {
         if (!(state instanceof Sign sign)) {
             throw new IllegalStateException("Oak wall sign did not create sign state");
         }
-        for (int line = 0; line < 4; line++) {
-            sign.getSide(Side.FRONT).line(line, DECORATIVE_TEXT);
+        List<Component> lines = signLines(placement.signKind());
+        for (int line = 0; line < lines.size(); line++) {
+            sign.getSide(Side.FRONT).line(line, lines.get(line));
         }
         if (!sign.update(true, false)) {
             throw new IllegalStateException("Could not configure physical quest-board sign");
         }
     }
 
+    @Override
+    public boolean matches(PhysicalBoardPlan.Placement placement, BoardFacing facing) {
+        Block block = block(placement.location());
+        Material material = Material.matchMaterial(placement.material());
+        if (material == null || block.getType() != material) {
+            return false;
+        }
+        if (!placement.sign()) {
+            return true;
+        }
+        if (!(block.getBlockData() instanceof WallSign wallSign)
+            || wallSign.getFacing() != facing.blockFace()
+            || !(block.getState() instanceof Sign sign)) {
+            return false;
+        }
+        List<Component> expected = signLines(placement.signKind());
+        for (int line = 0; line < expected.size(); line++) {
+            if (!expected.get(line).equals(sign.getSide(Side.FRONT).line(line))) {
+                return false;
+            }
+        }
+        return true;
+    }
+
     @Override
     public void restore(BoardId location, Object snapshot) {
         if (!(snapshot instanceof BlockState state) || !state.update(true, false)) {
@@ -70,6 +103,16 @@ final class BukkitPhysicalBoardWorld implements PhysicalBoardWorld {
         }
     }
 
+    static List<Component> signLines(PhysicalBoardSignKind kind) {
+        return switch (Objects.requireNonNull(kind, "kind")) {
+            case TITLE -> TITLE_TEXT;
+            case INSTRUCTION -> INSTRUCTION_TEXT;
+            case DECORATIVE -> List.of(
+                DECORATIVE_TEXT, DECORATIVE_TEXT, DECORATIVE_TEXT, DECORATIVE_TEXT
+            );
+        };
+    }
+
     private Block block(BoardId location) {
         if (!world.getUID().equals(location.worldId())) {
             throw new IllegalArgumentException("Physical board location belongs to another world");

src/main/java/games/dmg/spigotquestboard/PhysicalBoardPlan.java

@@ -22,8 +22,8 @@ record PhysicalBoardPlan(
     static PhysicalBoardPlan create(BoardId anchor, BoardFacing facing) {
         Objects.requireNonNull(anchor, "anchor");
         Objects.requireNonNull(facing, "facing");
-        List<Placement> placements = new ArrayList<>(23);
-        Set<BoardId> interactions = new LinkedHashSet<>(15);
+        List<Placement> placements = new ArrayList<>(25);
+        Set<BoardId> interactions = new LinkedHashSet<>(17);
 
         for (int height = 1; height <= 4; height++) {
             for (int lateral = -2; lateral <= 2; lateral++) {
@@ -37,12 +37,32 @@ record PhysicalBoardPlan(
         }
         for (int lateral = -1; lateral <= 1; lateral++) {
             BoardId location = offset(anchor, facing, lateral, 2, 1);
-            placements.add(new Placement(location, "OAK_WALL_SIGN"));
+            placements.add(new Placement(
+                location, "OAK_WALL_SIGN", PhysicalBoardSignKind.DECORATIVE
+            ));
             interactions.add(location);
         }
+        addSign(
+            placements, interactions, offset(anchor, facing, 0, 3, 1),
+            PhysicalBoardSignKind.INSTRUCTION
+        );
+        addSign(
+            placements, interactions, offset(anchor, facing, 0, 4, 1),
+            PhysicalBoardSignKind.TITLE
+        );
         return new PhysicalBoardPlan(facing, placements, interactions);
     }
 
+    private static void addSign(
+        List<Placement> placements,
+        Set<BoardId> interactions,
+        BoardId location,
+        PhysicalBoardSignKind kind
+    ) {
+        placements.add(new Placement(location, "OAK_WALL_SIGN", kind));
+        interactions.add(location);
+    }
+
     private static BoardId offset(
         BoardId anchor, BoardFacing facing, int lateral, int vertical, int forward
     ) {
@@ -54,14 +74,29 @@ record PhysicalBoardPlan(
         );
     }
 
-    record Placement(BoardId location, String material) {
+    record Placement(
+        BoardId location,
+        String material,
+        PhysicalBoardSignKind signKind
+    ) {
         Placement {
             Objects.requireNonNull(location, "location");
             Objects.requireNonNull(material, "material");
+            if ("OAK_WALL_SIGN".equals(material) != (signKind != null)) {
+                throw new IllegalArgumentException("Only wall signs require sign metadata");
+            }
+        }
+
+        Placement(BoardId location, String material) {
+            this(
+                location,
+                material,
+                "OAK_WALL_SIGN".equals(material) ? PhysicalBoardSignKind.DECORATIVE : null
+            );
         }
 
         boolean sign() {
-            return "OAK_WALL_SIGN".equals(material);
+            return signKind != null;
         }
     }
 }

src/main/java/games/dmg/spigotquestboard/PhysicalBoardSignKind.java

@@ -0,0 +1,7 @@
+package games.dmg.spigotquestboard;
+
+enum PhysicalBoardSignKind {
+    TITLE,
+    INSTRUCTION,
+    DECORATIVE
+}

src/main/java/games/dmg/spigotquestboard/PhysicalBoardUpgrader.java

@@ -0,0 +1,188 @@
+package games.dmg.spigotquestboard;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+import java.util.UUID;
+
+final class PhysicalBoardUpgrader {
+    interface WorldFactory {
+        PhysicalBoardWorld open(UUID worldId);
+    }
+
+    private record Candidate(BoardId anchor, BoardFacing facing, String worldName) { }
+    private record RelativeInteraction(int lateral, int height, int forward) { }
+
+    private static final List<RelativeInteraction> LEGACY_INTERACTIONS = legacyInteractions();
+
+    private final BoardRegistry registry;
+    private final WorldFactory worlds;
+
+    PhysicalBoardUpgrader(BoardRegistry registry, WorldFactory worlds) {
+        this.registry = Objects.requireNonNull(registry, "registry");
+        this.worlds = Objects.requireNonNull(worlds, "worlds");
+    }
+
+    int upgrade() throws IOException {
+        int upgraded = 0;
+        Map<BoardId, RegisteredBoard> registered = registry.registeredBoards();
+        for (Candidate candidate : candidates(registered)) {
+            if (!hasLegacyRegistrations(candidate, registered)) {
+                continue;
+            }
+            PhysicalBoardWorld world = worlds.open(candidate.anchor().worldId());
+            if (world != null && isLegacyBoard(candidate, world)
+                && upgrade(candidate, world)) {
+                upgraded++;
+                registered = registry.registeredBoards();
+            }
+        }
+        return upgraded;
+    }
+
+    private static boolean hasLegacyRegistrations(
+        Candidate candidate, Map<BoardId, RegisteredBoard> registered
+    ) {
+        PhysicalBoardPlan plan = PhysicalBoardPlan.create(candidate.anchor(), candidate.facing());
+        for (BoardId location : legacyInteractionLocations(plan)) {
+            RegisteredBoard board = registered.get(location);
+            if (board == null || !candidate.worldName().equals(board.worldName())) {
+                return false;
+            }
+        }
+        return newSigns(plan).stream().noneMatch(sign ->
+            registered.containsKey(sign.location())
+        );
+    }
+
+    private boolean isLegacyBoard(Candidate candidate, PhysicalBoardWorld world) {
+        PhysicalBoardPlan plan = PhysicalBoardPlan.create(candidate.anchor(), candidate.facing());
+        for (PhysicalBoardPlan.Placement placement : legacyPlacements(plan)) {
+            if (!world.matches(placement, candidate.facing())) {
+                return false;
+            }
+        }
+        for (PhysicalBoardPlan.Placement placement : newSigns(plan)) {
+            if (!world.isEmpty(placement.location())) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    private boolean upgrade(Candidate candidate, PhysicalBoardWorld world) throws IOException {
+        List<PhysicalBoardPlan.Placement> signs = newSigns(
+            PhysicalBoardPlan.create(candidate.anchor(), candidate.facing())
+        );
+        Map<BoardId, Object> snapshots = new LinkedHashMap<>();
+        try {
+            for (PhysicalBoardPlan.Placement sign : signs) {
+                snapshots.put(sign.location(), world.snapshot(sign.location()));
+            }
+            for (PhysicalBoardPlan.Placement sign : signs) {
+                world.place(sign, candidate.facing());
+            }
+            List<RegisteredBoard> additions = signs.stream()
+                .map(sign -> new RegisteredBoard(sign.location(), candidate.worldName()))
+                .toList();
+            if (registry.registerAll(additions) != BoardRegistrationResult.CREATED) {
+                rollback(world, snapshots, null);
+                return false;
+            }
+            return true;
+        } catch (RuntimeException | IOException exception) {
+            rollback(world, snapshots, exception);
+            if (exception instanceof IOException ioException) {
+                throw ioException;
+            }
+            throw new IOException("Could not upgrade physical quest board", exception);
+        }
+    }
+
+    private static Set<Candidate> candidates(Map<BoardId, RegisteredBoard> registered) {
+        Set<Candidate> candidates = new LinkedHashSet<>();
+        for (RegisteredBoard board : registered.values()) {
+            for (BoardFacing facing : BoardFacing.values()) {
+                for (RelativeInteraction relative : LEGACY_INTERACTIONS) {
+                    BoardId location = board.id();
+                    candidates.add(new Candidate(new BoardId(
+                        location.worldId(),
+                        location.x() - relative.lateral() * facing.rightX()
+                            - relative.forward() * facing.x(),
+                        location.y() - relative.height(),
+                        location.z() - relative.lateral() * facing.rightZ()
+                            - relative.forward() * facing.z()
+                    ), facing, board.worldName()));
+                }
+            }
+        }
+        return candidates;
+    }
+
+    private static List<RelativeInteraction> legacyInteractions() {
+        List<RelativeInteraction> interactions = new ArrayList<>(15);
+        for (int height = 1; height <= 4; height++) {
+            for (int lateral = -1; lateral <= 1; lateral++) {
+                interactions.add(new RelativeInteraction(lateral, height, 0));
+            }
+        }
+        for (int lateral = -1; lateral <= 1; lateral++) {
+            interactions.add(new RelativeInteraction(lateral, 2, 1));
+        }
+        return List.copyOf(interactions);
+    }
+
+    private static List<PhysicalBoardPlan.Placement> legacyPlacements(PhysicalBoardPlan plan) {
+        return plan.placements().stream().filter(placement ->
+            !placement.sign() || placement.signKind() == PhysicalBoardSignKind.DECORATIVE
+        ).toList();
+    }
+
+    private static Set<BoardId> legacyInteractionLocations(PhysicalBoardPlan plan) {
+        Set<BoardId> locations = new LinkedHashSet<>();
+        for (PhysicalBoardPlan.Placement placement : legacyPlacements(plan)) {
+            if ("OAK_PLANKS".equals(placement.material()) || placement.sign()) {
+                locations.add(placement.location());
+            }
+        }
+        return Set.copyOf(locations);
+    }
+
+    private static List<PhysicalBoardPlan.Placement> newSigns(PhysicalBoardPlan plan) {
+        return plan.placements().stream().filter(placement ->
+            placement.signKind() == PhysicalBoardSignKind.TITLE
+                || placement.signKind() == PhysicalBoardSignKind.INSTRUCTION
+        ).toList();
+    }
+
+    private static void rollback(
+        PhysicalBoardWorld world, Map<BoardId, Object> snapshots, Throwable failure
+    ) throws IOException {
+        RuntimeException rollbackFailure = null;
+        List<Map.Entry<BoardId, Object>> entries = new ArrayList<>(snapshots.entrySet());
+        for (int index = entries.size() - 1; index >= 0; index--) {
+            Map.Entry<BoardId, Object> entry = entries.get(index);
+            try {
+                world.restore(entry.getKey(), entry.getValue());
+            } catch (RuntimeException exception) {
+                if (rollbackFailure == null) {
+                    rollbackFailure = exception;
+                } else {
+                    rollbackFailure.addSuppressed(exception);
+                }
+            }
+        }
+        if (rollbackFailure != null) {
+            if (failure != null) {
+                failure.addSuppressed(rollbackFailure);
+            } else {
+                throw new IOException("Could not restore physical board upgrade", rollbackFailure);
+            }
+        }
+    }
+}

src/main/java/games/dmg/spigotquestboard/PhysicalBoardWorld.java

@@ -7,5 +7,9 @@ interface PhysicalBoardWorld {
 
     void place(PhysicalBoardPlan.Placement placement, BoardFacing facing);
 
+    default boolean matches(PhysicalBoardPlan.Placement placement, BoardFacing facing) {
+        return false;
+    }
+
     void restore(BoardId location, Object snapshot);
 }

src/main/java/games/dmg/spigotquestboard/SpigotQuestBoardPlugin.java

@@ -13,10 +13,15 @@ public final class SpigotQuestBoardPlugin extends JavaPlugin {
         final BoardRegistry boards;
         final QuestService quests;
         final PlayerCommandSettings playerCommands;
+        final int upgradedBoards;
         try {
             boards = new BoardRegistry(new YamlBoardRepository(
                 getDataFolder().toPath().resolve("boards.yml")
             ));
+            upgradedBoards = upgradePhysicalBoards(boards, worldId -> {
+                org.bukkit.World world = getServer().getWorld(worldId);
+                return world == null ? null : new BukkitPhysicalBoardWorld(world);
+            });
             quests = new QuestService(new YamlQuestRepository(
                 getDataFolder().toPath().resolve("quests.yml")
             ));
@@ -69,10 +74,17 @@ public final class SpigotQuestBoardPlugin extends JavaPlugin {
         );
         getLogger().info(
             "Spigot Quest Board enabled with " + boards.size() + " boards and "
-                + quests.state().quests().size() + " quests."
+                + quests.state().quests().size() + " quests; upgraded " + upgradedBoards
+                + " physical boards."
         );
     }
 
+    static int upgradePhysicalBoards(
+        BoardRegistry boards, PhysicalBoardUpgrader.WorldFactory worlds
+    ) throws IOException {
+        return new PhysicalBoardUpgrader(boards, worlds).upgrade();
+    }
+
     static CommandHandlers commandHandlers(
         BoardRegistry boards,
         PlayerCommandSettings playerCommands,