Implements #5 and stuff

Uses a player entry state to store and restore a player's state such as game-mode and fly-mode.
Removes the restriction of fly mode and game-mode, and sets all arena players to adventure mode.
Force-quits all sessions when exiting the plugin.
Prevents usage of any commands other than the leave command when playing in an arena.

README.md

@@ -26,6 +26,7 @@ To modify
 | /droppercreate               | \<name>                     | Creates a new dropper arena with the given name |
 | /dropperremove               | \<arena>                    | Removes the specified dropper arena             |
 | [/dropperedit](#dropperedit) | \<arena> \<option> \[value] | Gets or sets a dropper arena option             |
+| /dropperreload               |                             | Reloads all data from disk                      |
 
 ## Command explanation
 

src/main/java/net/knarcraft/dropper/Dropper.java

@@ -3,6 +3,7 @@ package net.knarcraft.dropper;
 import net.knarcraft.dropper.arena.DropperArenaHandler;
 import net.knarcraft.dropper.arena.DropperArenaPlayerRegistry;
 import net.knarcraft.dropper.arena.DropperArenaRecordsRegistry;
+import net.knarcraft.dropper.arena.DropperArenaSession;
 import net.knarcraft.dropper.command.CreateArenaCommand;
 import net.knarcraft.dropper.command.EditArenaCommand;
 import net.knarcraft.dropper.command.EditArenaTabCompleter;
@@ -15,6 +16,7 @@ import net.knarcraft.dropper.command.RemoveArenaCommand;
 import net.knarcraft.dropper.command.RemoveArenaTabCompleter;
 import net.knarcraft.dropper.container.SerializableMaterial;
 import net.knarcraft.dropper.container.SerializableUUID;
+import net.knarcraft.dropper.listener.CommandListener;
 import net.knarcraft.dropper.listener.DamageListener;
 import net.knarcraft.dropper.listener.MoveListener;
 import net.knarcraft.dropper.listener.PlayerLeaveListener;
@@ -22,6 +24,7 @@ import org.bukkit.command.CommandExecutor;
 import org.bukkit.command.PluginCommand;
 import org.bukkit.command.TabCompleter;
 import org.bukkit.configuration.serialization.ConfigurationSerialization;
+import org.bukkit.entity.Player;
 import org.bukkit.plugin.PluginManager;
 import org.bukkit.plugin.java.JavaPlugin;
 import org.jetbrains.annotations.NotNull;
@@ -91,8 +94,6 @@ public final class Dropper extends JavaPlugin {
         this.arenaHandler = new DropperArenaHandler();
         this.arenaHandler.loadArenas();
 
-        //TODO: Add a command for joining a specific arena. Only teleport if the stage check succeeds (The server can 
-        // use something like https://www.spigotmc.org/resources/commandblocks.62720/ for immersion)
         //TODO: Store various information about players' performance, and hook into PlaceholderAPI
 
         //TODO: Possibly implement an optional queue mode, which only allows one player inside one dropper arena at any 
@@ -105,6 +106,7 @@ public final class Dropper extends JavaPlugin {
         pluginManager.registerEvents(new DamageListener(), this);
         pluginManager.registerEvents(new MoveListener(), this);
         pluginManager.registerEvents(new PlayerLeaveListener(), this);
+        pluginManager.registerEvents(new CommandListener(), this);
 
         registerCommand("dropperreload", new ReloadCommand(), null);
         registerCommand("droppercreate", new CreateArenaCommand(), null);
@@ -117,7 +119,13 @@ public final class Dropper extends JavaPlugin {
 
     @Override
     public void onDisable() {
-
+        // Throw out currently playing players before exiting
+        for (Player player : getServer().getOnlinePlayers()) {
+            DropperArenaSession session = playerRegistry.getArenaSession(player.getUniqueId());
+            if (session != null) {
+                session.triggerQuit(true);
+            }
+        }
     }
 
     /**

src/main/java/net/knarcraft/dropper/arena/DropperArena.java

@@ -36,7 +36,7 @@ public class DropperArena {
      *
      * <p>This is technically the fly speed</p>
      */
-    private final double playerHorizontalVelocity;
+    private final float playerHorizontalVelocity;
 
     /**
      * The stage number of this arena. If not null, the previous stage number must be cleared before access.
@@ -53,8 +53,7 @@ public class DropperArena {
      */
     private final @NotNull Material winBlockType;
 
-    //TODO: Store records for this arena (maps with player->deaths/time). It should be possible to get those in sorted 
+    //TODO: It should be possible to get records in sorted order (smallest to largest)
-    // order (smallest to largest)
 
     /**
      * Instantiates a new dropper arena
@@ -63,14 +62,14 @@ public class DropperArena {
      * @param spawnLocation            <p>The location players spawn in when entering the arena</p>
      * @param exitLocation             <p>The location the players are teleported to when exiting the arena, or null</p>
      * @param playerVerticalVelocity   <p>The velocity to use for players' vertical velocity</p>
-     * @param playerHorizontalVelocity <p>The velocity to use for players' horizontal velocity</p>
+     * @param playerHorizontalVelocity <p>The velocity to use for players' horizontal velocity (-1 to 1)</p>
      * @param stage                    <p>The stage number of this stage, or null if not limited to stages</p>
      * @param winBlockType             <p>The material of the block players have to hit to win this dropper arena</p>
      * @param recordsRegistry          <p>The registry keeping track of all of this arena's records</p>
      */
     public DropperArena(@NotNull String arenaName, @NotNull Location spawnLocation, @Nullable Location exitLocation,
-                        double playerVerticalVelocity, double playerHorizontalVelocity, @Nullable Integer stage, @NotNull Material winBlockType,
+                        double playerVerticalVelocity, float playerHorizontalVelocity, @Nullable Integer stage,
-                        @NotNull DropperArenaRecordsRegistry recordsRegistry) {
+                        @NotNull Material winBlockType, @NotNull DropperArenaRecordsRegistry recordsRegistry) {
         this.arenaName = arenaName;
         this.spawnLocation = spawnLocation;
         this.exitLocation = exitLocation;
@@ -158,7 +157,7 @@ public class DropperArena {
      *
      * @return <p>Players' velocity in this arena</p>
      */
-    public double getPlayerHorizontalVelocity() {
+    public float getPlayerHorizontalVelocity() {
         return this.playerHorizontalVelocity;
     }
 

src/main/java/net/knarcraft/dropper/arena/DropperArenaPlayerRegistry.java

@@ -52,7 +52,7 @@ public class DropperArenaPlayerRegistry {
         for (Map.Entry<UUID, DropperArenaSession> entry : this.arenaPlayers.entrySet()) {
             if (entry.getValue().getArena() == arena) {
                 // Kick the player gracefully
-                entry.getValue().triggerQuit();
+                entry.getValue().triggerQuit(false);
                 this.arenaPlayers.remove(entry.getKey());
             }
         }

src/main/java/net/knarcraft/dropper/arena/DropperArenaSession.java

@@ -18,10 +18,9 @@ public class DropperArenaSession {
     private final @NotNull DropperArena arena;
     private final @NotNull Player player;
     private final @NotNull ArenaGameMode gameMode;
-    private final @NotNull Location entryLocation;
     private int deaths;
     private final long startTime;
-    private final float playersOriginalFlySpeed;
+    private final PlayerEntryState entryState;
 
     /**
      * Instantiates a new dropper arena session
@@ -37,13 +36,19 @@ public class DropperArenaSession {
         this.gameMode = gameMode;
         this.deaths = 0;
         this.startTime = System.currentTimeMillis();
-        this.entryLocation = player.getLocation();
 
+        this.entryState = new PlayerEntryState(player);
         // Make the player fly to improve mobility in the air
-        player.setAllowFlight(true);
+        this.entryState.setArenaState(this.arena.getPlayerHorizontalVelocity());
-        player.setFlying(true);
+    }
-        this.playersOriginalFlySpeed = player.getFlySpeed();
+
-        player.setFlySpeed((float) this.arena.getPlayerHorizontalVelocity());
+    /**
+     * Gets the state of the player when they joined the session
+     *
+     * @return <p>The player's entry state</p>
+     */
+    public @NotNull PlayerEntryState getEntryState() {
+        return this.entryState;
     }
 
     /**
@@ -70,21 +75,21 @@ public class DropperArenaSession {
         this.player.sendMessage("You won!");
 
         // Teleport the player out of the arena
-        teleportToExit();
+        teleportToExit(false);
     }
 
     /**
      * Teleports the playing player out of the arena
      */
-    private void teleportToExit() {
+    private void teleportToExit(boolean immediately) {
         // Teleport the player out of the arena
         Location exitLocation;
         if (this.arena.getExitLocation() != null) {
             exitLocation = this.arena.getExitLocation();
         } else {
-            exitLocation = this.entryLocation;
+            exitLocation = this.entryState.getEntryLocation();
         }
-        PlayerTeleporter.teleportPlayer(this.player, exitLocation, true);
+        PlayerTeleporter.teleportPlayer(this.player, exitLocation, true, immediately);
     }
 
     /**
@@ -125,17 +130,17 @@ public class DropperArenaSession {
             this.deaths++;
         }
         //Teleport the player back to the top
-        PlayerTeleporter.teleportPlayer(this.player, this.arena.getSpawnLocation(), true);
+        PlayerTeleporter.teleportPlayer(this.player, this.arena.getSpawnLocation(), true, false);
     }
 
     /**
      * Triggers a quit for the player playing in this session
      */
-    public void triggerQuit() {
+    public void triggerQuit(boolean immediately) {
         // Stop this session
         stopSession();
         // Teleport the player out of the arena
-        teleportToExit();
+        teleportToExit(immediately);
 
         player.sendMessage("You quit the arena!");
     }
@@ -148,9 +153,7 @@ public class DropperArenaSession {
         removeSession();
 
         // Remove flight mode
-        this.player.setFlySpeed(this.playersOriginalFlySpeed);
+        entryState.restore();
-        this.player.setFlying(false);
-        this.player.setAllowFlight(false);
     }
 
     /**

src/main/java/net/knarcraft/dropper/arena/PlayerEntryState.java

@@ -0,0 +1,71 @@
+package net.knarcraft.dropper.arena;
+
+import org.bukkit.GameMode;
+import org.bukkit.Location;
+import org.bukkit.entity.Player;
+
+/**
+ * The state of a player before entering a dropper arena
+ */
+public class PlayerEntryState {
+
+    private final Player player;
+    private final Location entryLocation;
+    private final boolean originalIsFlying;
+    private final float originalFlySpeed;
+    private final GameMode originalGameMode;
+    private final boolean originalAllowFlight;
+    private final boolean originalInvulnerable;
+    private final boolean originalIsSwimming;
+
+    /**
+     * Instantiates a new player state
+     *
+     * @param player <p>The player whose state should be stored</p>
+     */
+    public PlayerEntryState(Player player) {
+        this.player = player;
+        this.entryLocation = player.getLocation();
+        this.originalFlySpeed = player.getFlySpeed();
+        this.originalIsFlying = player.isFlying();
+        this.originalGameMode = player.getGameMode();
+        this.originalAllowFlight = player.getAllowFlight();
+        this.originalInvulnerable = player.isInvulnerable();
+        this.originalIsSwimming = player.isSwimming();
+    }
+
+    /**
+     * Sets the state of the stored player to the state used by arenas
+     *
+     * @param horizontalVelocity <p>The horizontal velocity to apply to the player</p>
+     */
+    public void setArenaState(float horizontalVelocity) {
+        this.player.setAllowFlight(true);
+        this.player.setFlying(true);
+        this.player.setFlySpeed(horizontalVelocity);
+        this.player.setGameMode(GameMode.ADVENTURE);
+        this.player.setSwimming(false);
+    }
+
+    /**
+     * Restores the stored state for the stored player
+     */
+    public void restore() {
+        this.player.setFlying(this.originalIsFlying);
+        this.player.setGameMode(this.originalGameMode);
+        this.player.setAllowFlight(this.originalAllowFlight);
+        this.player.setFlySpeed(this.originalFlySpeed);
+        this.player.setInvulnerable(this.originalInvulnerable);
+        this.player.setSwimming(this.originalIsSwimming);
+    }
+
+    /**
+     * Gets the location the player entered from
+     *
+     * @return <p>The location the player entered from</p>
+     */
+    public Location getEntryLocation() {
+        return this.entryLocation;
+    }
+
+}

src/main/java/net/knarcraft/dropper/command/JoinArenaCommand.java

@@ -6,7 +6,6 @@ import net.knarcraft.dropper.arena.DropperArenaPlayerRegistry;
 import net.knarcraft.dropper.arena.DropperArenaSession;
 import net.knarcraft.dropper.property.ArenaGameMode;
 import net.knarcraft.dropper.util.PlayerTeleporter;
-import org.bukkit.GameMode;
 import org.bukkit.command.Command;
 import org.bukkit.command.CommandExecutor;
 import org.bukkit.command.CommandSender;
@@ -30,12 +29,6 @@ public class JoinArenaCommand implements CommandExecutor {
             return false;
         }
 
-        if (player.isFlying() || player.getGameMode() == GameMode.CREATIVE ||
-                player.getGameMode() == GameMode.SPECTATOR) {
-            commandSender.sendMessage("You cannot join a dropper arena while able to fly!");
-            return false;
-        }
-
         // Disallow joining if the player is already in a dropper arena
         DropperArenaSession existingSession = Dropper.getInstance().getPlayerRegistry().getArenaSession(player.getUniqueId());
         if (existingSession != null) {
@@ -50,6 +43,24 @@ public class JoinArenaCommand implements CommandExecutor {
             return false;
         }
 
+        // Deny vehicles as allowing this is tricky, and will cause problems in some cases
+        if (player.isInsideVehicle() || !player.getPassengers().isEmpty()) {
+            commandSender.sendMessage("You cannot join an arena while inside a vehicle or carrying a passenger.");
+            return false;
+        }
+
+        return joinArena(specifiedArena, player, arguments);
+    }
+
+    /**
+     * Performs the actual arena joining
+     *
+     * @param specifiedArena <p>The arena the player wants to join</p>
+     * @param player         <p>The player joining the arena</p>
+     * @param arguments      <p>The arguments given</p>
+     * @return <p>Whether the arena was joined successfully</p>
+     */
+    private boolean joinArena(DropperArena specifiedArena, Player player, String[] arguments) {
         // Find the specified game-mode
         ArenaGameMode gameMode;
         if (arguments.length > 1) {
@@ -66,13 +77,15 @@ public class JoinArenaCommand implements CommandExecutor {
         playerRegistry.registerPlayer(player.getUniqueId(), newSession);
 
         // Try to teleport the player to the arena
-        boolean teleported = PlayerTeleporter.teleportPlayer(player, specifiedArena.getSpawnLocation(), false);
+        boolean teleported = PlayerTeleporter.teleportPlayer(player, specifiedArena.getSpawnLocation(), false, false);
         if (!teleported) {
-            commandSender.sendMessage("Unable to teleport you to the dropper arena. Make sure you're not in a vehicle," +
+            player.sendMessage("Unable to teleport you to the dropper arena. Make sure you're not in a vehicle," +
-                    "and is not carrying a passenger!");
+                    "and not carrying a passenger!");
-            newSession.triggerQuit();
+            newSession.triggerQuit(false);
             return false;
         } else {
+            // Make sure to update the state again in the air to remove a potential swimming state
+            newSession.getEntryState().setArenaState(specifiedArena.getPlayerHorizontalVelocity());
             return true;
         }
     }

src/main/java/net/knarcraft/dropper/command/LeaveArenaCommand.java

@@ -32,7 +32,7 @@ public class LeaveArenaCommand implements TabExecutor {
             return false;
         }
 
-        existingSession.triggerQuit();
+        existingSession.triggerQuit(false);
         return true;
     }
 

src/main/java/net/knarcraft/dropper/listener/CommandListener.java

@@ -0,0 +1,46 @@
+package net.knarcraft.dropper.listener;
+
+import net.knarcraft.dropper.Dropper;
+import net.knarcraft.dropper.arena.DropperArenaSession;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.Listener;
+import org.bukkit.event.player.PlayerCommandPreprocessEvent;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * A listener for players trying to use commands while inside a dropper arena
+ */
+public class CommandListener implements Listener {
+
+    @EventHandler
+    public void onCommand(PlayerCommandPreprocessEvent event) {
+        Player player = event.getPlayer();
+        DropperArenaSession existingSession = Dropper.getInstance().getPlayerRegistry().getArenaSession(
+                player.getUniqueId());
+        if (existingSession == null) {
+            return;
+        }
+
+        List<String> allowedCommands = new ArrayList<>();
+        allowedCommands.add("/dropperleave");
+        allowedCommands.add("/dleave");
+
+        String message = event.getMessage();
+        if (!message.startsWith("/")) {
+            return;
+        }
+
+        for (String command : allowedCommands) {
+            if (message.equals(command)) {
+                return;
+            }
+        }
+
+        player.sendMessage("You cannot use that command while in an arena!");
+        event.setCancelled(true);
+    }
+
+}

src/main/java/net/knarcraft/dropper/listener/PlayerLeaveListener.java

@@ -44,7 +44,7 @@ public class PlayerLeaveListener implements Listener {
         if (leftSessions.containsKey(playerId)) {
             Dropper.getInstance().getLogger().log(Level.WARNING, "Found un-exited dropper session!");
             Bukkit.getScheduler().runTaskLater(Dropper.getInstance(), () -> {
-                leftSessions.get(playerId).triggerQuit();
+                leftSessions.get(playerId).triggerQuit(false);
                 Dropper.getInstance().getLogger().log(Level.WARNING, "Triggered a quit!");
                 leftSessions.remove(playerId);
             }, 80);
@@ -66,7 +66,7 @@ public class PlayerLeaveListener implements Listener {
             return;
         }
 
-        arenaSession.triggerQuit();
+        arenaSession.triggerQuit(false);
     }
 
     /**

src/main/java/net/knarcraft/dropper/property/ArenaGameMode.java

@@ -9,7 +9,6 @@ public enum ArenaGameMode {
 
     /**
      * The default game-mode. Failing once throws the player out.
-     * //TODO: Verify if we want the default game-mode to lock the player in the arena until they beat it
      */
     DEFAULT,
 

src/main/java/net/knarcraft/dropper/util/ArenaStorageHelper.java

@@ -53,7 +53,6 @@ public final class ArenaStorageHelper {
             configSection.set(ArenaStorageKey.WIN_BLOCK_TYPE.getKey(), new SerializableMaterial(arena.getWinBlockType()));
             configSection.set(ArenaStorageKey.RECORDS.getKey(), arena.getRecordsRegistry());
         }
-        //TODO: Save records belonging to the arena
         configuration.save(arenaFile);
     }
 
@@ -100,7 +99,8 @@ public final class ArenaStorageHelper {
         Location spawnLocation = (Location) configurationSection.get(ArenaStorageKey.SPAWN_LOCATION.getKey());
         Location exitLocation = (Location) configurationSection.get(ArenaStorageKey.EXIT_LOCATION.getKey());
         double verticalVelocity = configurationSection.getDouble(ArenaStorageKey.PLAYER_VERTICAL_VELOCITY.getKey());
-        double horizontalVelocity = configurationSection.getDouble(ArenaStorageKey.PLAYER_HORIZONTAL_VELOCITY.getKey());
+        float horizontalVelocity = sanitizeHorizontalVelocity((float) configurationSection.getDouble(
+                ArenaStorageKey.PLAYER_HORIZONTAL_VELOCITY.getKey()));
         Integer stage = (Integer) configurationSection.get(ArenaStorageKey.STAGE.getKey());
         SerializableMaterial winBlockType = (SerializableMaterial) configurationSection.get(
                 ArenaStorageKey.WIN_BLOCK_TYPE.getKey());
@@ -133,4 +133,20 @@ public final class ArenaStorageHelper {
         return arenaName.toLowerCase().trim().replaceAll(" ", "_");
     }
 
+    /**
+     * Sanitizes the given horizontal velocity to make sure it doesn't leave its bounds
+     *
+     * @param horizontalVelocity <p>The horizontal velocity to sanitize</p>
+     * @return <p>The sanitized horizontal velocity</p>
+     */
+    private static float sanitizeHorizontalVelocity(float horizontalVelocity) {
+        if (horizontalVelocity < -1) {
+            return -1;
+        } else if (horizontalVelocity > 1) {
+            return 1;
+        } else {
+            return horizontalVelocity;
+        }
+    }
+
 }

src/main/java/net/knarcraft/dropper/util/PlayerTeleporter.java

@@ -21,12 +21,13 @@ public final class PlayerTeleporter {
      *
      * <p>Forcing teleport should only be used inside an arena, to prevent the player from becoming stuck.</p>
      *
-     * @param player   <p>The player about to teleport</p>
+     * @param player      <p>The player about to teleport</p>
-     * @param location <p>The location the player should be teleported to</p>
+     * @param location    <p>The location the player should be teleported to</p>
-     * @param force    <p>Whether to force a player teleport, even in a vehicle or a passenger</p>
+     * @param force       <p>Whether to force a player teleport, even in a vehicle or a passenger</p>
+     * @param immediately <p>Whether to to the teleportation immediately, not using any timers</p>
      * @return <p>True if the player was successfully teleported</p>
      */
-    public static boolean teleportPlayer(Player player, Location location, boolean force) {
+    public static boolean teleportPlayer(Player player, Location location, boolean force, boolean immediately) {
         if (!player.getPassengers().isEmpty()) {
             if (force) {
                 for (Entity passenger : player.getPassengers()) {
@@ -55,7 +56,11 @@ public final class PlayerTeleporter {
         player.setVelocity(new Vector(0, 0, 0));
         //When teleporting a player out of the arena, sometimes the move listener is slow to react, giving the player 
         // lethal velocity, and causing damage. That's why the player is given 5 ticks of invulnerability
-        Bukkit.getScheduler().runTaskLater(Dropper.getInstance(), () -> player.setInvulnerable(false), 5);
+        if (!immediately) {
+            Bukkit.getScheduler().runTaskLater(Dropper.getInstance(), () -> player.setInvulnerable(false), 5);
+        } else {
+            player.setInvulnerable(false);
+        }
         return true;
     }