Start BungeeCord synchronisation with plugin messaging channelfix/sync

- See #180

4 files changed, 183 insertions, 0 deletions

diff --git a/bungee/src/main/java/com/leonardobishop/quests/bungee/BungeeQuestsPlugin.java b/bungee/src/main/java/com/leonardobishop/quests/bungee/BungeeQuestsPlugin.java
new file mode 100644
index 00000000..b6769f2c
--- /dev/null
+++ b/bungee/src/main/java/com/leonardobishop/quests/bungee/BungeeQuestsPlugin.java
@@ -0,0 +1,26 @@
+package com.leonardobishop.quests.bungee;
+
+import com.leonardobishop.quests.bungee.listener.PluginMessageListener;
+import com.leonardobishop.quests.bungee.lock.DataLockManager;
+import com.leonardobishop.quests.common.enums.PluginMessagingChannels;
+import net.md_5.bungee.api.plugin.Plugin;
+
+public class BungeeQuestsPlugin extends Plugin {
+
+    private DataLockManager dataLockManager;
+
+    @Override
+    public void onEnable() {
+        this.dataLockManager = new DataLockManager();
+
+        //TODO: https://github.com/LMBishop/Quests/issues/180
+
+//        super.getProxy().registerChannel(PluginMessagingChannels.QUESTS_LOCKS_CHANNEL);
+//        super.getProxy().getPluginManager().registerListener(this, new PluginMessageListener(this));
+    }
+
+    public DataLockManager getDataLockManager() {
+        return dataLockManager;
+    }
+
+}
diff --git a/bungee/src/main/java/com/leonardobishop/quests/bungee/listener/PluginMessageListener.java b/bungee/src/main/java/com/leonardobishop/quests/bungee/listener/PluginMessageListener.java
new file mode 100644
index 00000000..e54d094c
--- /dev/null
+++ b/bungee/src/main/java/com/leonardobishop/quests/bungee/listener/PluginMessageListener.java
@@ -0,0 +1,69 @@
+package com.leonardobishop.quests.bungee.listener;
+
+import com.leonardobishop.quests.bungee.BungeeQuestsPlugin;
+import com.leonardobishop.quests.common.enums.PluginMessagingChannels;
+import net.md_5.bungee.api.config.ServerInfo;
+import net.md_5.bungee.api.connection.ProxiedPlayer;
+import net.md_5.bungee.api.connection.Server;
+import net.md_5.bungee.api.event.PluginMessageEvent;
+import net.md_5.bungee.api.plugin.Listener;
+import net.md_5.bungee.event.EventHandler;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.UUID;
+
+public class PluginMessageListener implements Listener {
+
+    private final BungeeQuestsPlugin plugin;
+
+    public PluginMessageListener(BungeeQuestsPlugin plugin) {
+        this.plugin = plugin;
+    }
+
+    @EventHandler
+    public void onPluginMessage(PluginMessageEvent e) {
+        if (!e.getTag().equals(PluginMessagingChannels.QUESTS_LOCKS_CHANNEL)) {
+            return;
+        }
+        e.setCancelled(true);
+        if (!(e.getSender() instanceof Server) || !(e.getReceiver() instanceof ProxiedPlayer)) {
+            return;
+        }
+        Server sender = (Server) e.getSender();
+
+        ByteArrayInputStream stream = new ByteArrayInputStream(e.getData());
+        DataInputStream in = new DataInputStream(stream);
+        try {
+            String request = in.readUTF();
+            UUID uuid = UUID.fromString(in.readUTF());
+
+            if (request.equals("acquireLock")) {
+                plugin.getDataLockManager().acquireLock(sender.getInfo().getName(), uuid,
+                        () -> sendMessage(sender.getInfo().getName(), "lockAcquired", uuid));
+            }
+        } catch (Exception ex) {
+            plugin.getLogger().warning("Could not parse plugin message:");
+            ex.printStackTrace();
+        }
+    }
+
+    public void sendMessage(String server, String request, UUID who) {
+        ByteArrayOutputStream stream = new ByteArrayOutputStream();
+        DataOutputStream out = new DataOutputStream(stream);
+        try {
+            out.writeUTF(request);
+            out.writeUTF(who.toString());
+        } catch (IOException ex) {
+            plugin.getLogger().warning("Could not write plugin message:");
+            ex.printStackTrace();
+        }
+
+        ServerInfo serverInfo = plugin.getProxy().getServerInfo(server);
+        if (serverInfo != null) serverInfo.sendData(PluginMessagingChannels.QUESTS_LOCKS_CHANNEL, stream.toByteArray());
+    }
+
+}
diff --git a/bungee/src/main/java/com/leonardobishop/quests/bungee/lock/DataLockManager.java b/bungee/src/main/java/com/leonardobishop/quests/bungee/lock/DataLockManager.java
new file mode 100644
index 00000000..ed80fd94
--- /dev/null
+++ b/bungee/src/main/java/com/leonardobishop/quests/bungee/lock/DataLockManager.java
@@ -0,0 +1,67 @@
+package com.leonardobishop.quests.bungee.lock;
+
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
+
+//TODO https://github.com/LMBishop/Quests/issues/180
+public class DataLockManager {
+
+    private final Map<UUID, String> locks = new HashMap<>();
+    private final Map<UUID, LinkedList<QueuedServer>> queue = new HashMap<>();
+
+    public synchronized boolean hasLock(String server, UUID who) {
+        String lockedServer = locks.get(who);
+        if (lockedServer == null) {
+            return false;
+        } else {
+            return lockedServer.equals(server);
+        }
+    }
+
+    public synchronized void acquireLock(String server, UUID who, Runnable callback) {
+        String lockedServer = locks.get(who);
+        if (lockedServer == null) {
+            locks.put(who, server);
+            callback.run();
+        } else if (lockedServer.equals(server)) {
+            callback.run();
+        }
+        CompletableFuture<Void> future = new CompletableFuture<>();
+        QueuedServer queuedServer = new QueuedServer(callback, server);
+        queue.compute(who, (uuid, list) -> {
+            if (list == null) {
+                LinkedList<QueuedServer> newList = new LinkedList<>();
+                newList.add(queuedServer);
+                return newList;
+            } else {
+                list.add(queuedServer);
+            }
+            return list;
+        });
+    }
+
+    public synchronized void releaseLock(String server, UUID who) {
+        String lockedServer = locks.get(who);
+        if (lockedServer == null || lockedServer.equals(server)) {
+            LinkedList<QueuedServer> queuedServers = queue.get(who);
+            QueuedServer nextServer = queuedServers.poll();
+            if (nextServer != null) {
+                locks.put(who, nextServer.getServer());
+                nextServer.getCallback().run();
+            } else {
+                locks.remove(who);
+            }
+        } else {
+            LinkedList<QueuedServer> queuedServers = queue.get(who);
+            QueuedServer queuedServer = null;
+            for (QueuedServer qs : queuedServers) {
+                if (qs.getServer().equals(server)) queuedServer = qs;
+            }
+            if (queuedServer != null) queuedServers.remove(queuedServer);
+        }
+    }
+
+}
diff --git a/bungee/src/main/java/com/leonardobishop/quests/bungee/lock/QueuedServer.java b/bungee/src/main/java/com/leonardobishop/quests/bungee/lock/QueuedServer.java
new file mode 100644
index 00000000..90a68987
--- /dev/null
+++ b/bungee/src/main/java/com/leonardobishop/quests/bungee/lock/QueuedServer.java
@@ -0,0 +1,21 @@
+package com.leonardobishop.quests.bungee.lock;
+
+public class QueuedServer {
+
+    private Runnable callback;
+    private String server;
+
+    public QueuedServer(Runnable callback, String server) {
+        this.callback = callback;
+        this.server = server;
+    }
+
+    public Runnable getCallback() {
+        return callback;
+    }
+
+    public String getServer() {
+        return server;
+    }
+
+}