Add debug helper class for ProtocolLib

Plugin/src/main/java/com/gmail/filoghost/holographicdisplays/bridge/protocollib/current/DebugHelper.java

@@ -0,0 +1,107 @@
+/*
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *  
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *  GNU General Public License for more details.
+ *  
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.gmail.filoghost.holographicdisplays.bridge.protocollib.current;
+
+import java.util.Map;
+
+import com.comphenix.net.sf.cglib.proxy.Factory;
+import com.comphenix.protocol.events.PacketContainer;
+import com.comphenix.protocol.events.PacketEvent;
+import com.comphenix.protocol.reflect.EquivalentConverter;
+import com.comphenix.protocol.reflect.PrettyPrinter;
+import com.comphenix.protocol.reflect.PrettyPrinter.ObjectPrinter;
+import com.comphenix.protocol.utility.HexDumper;
+import com.comphenix.protocol.utility.MinecraftReflection;
+import com.comphenix.protocol.wrappers.BukkitConverters;
+
+public class DebugHelper {
+	
+	private static final int HEX_DUMP_THRESHOLD = 256;
+	
+	public static void printInformation(PacketEvent event) {
+		String verb = event.isServerPacket() ? "Sent" : "Received";
+		String format = event.isServerPacket() ? 
+				"%s %s to %s" : 
+				"%s %s from %s";
+		
+		String shortDescription = String.format(format,
+				event.isCancelled() ? "Cancelled" : verb,
+				event.getPacketType(),
+				event.getPlayer().getName()
+		);
+		
+		// Detailed will print the packet's content too
+		try {			
+			System.out.println(shortDescription + ":\n" + getPacketDescription(event.getPacket()));
+		} catch (IllegalAccessException e) {
+			e.printStackTrace();
+			System.out.println("Unable to use reflection.");
+		}
+	}
+	
+	
+	private static String getPacketDescription(PacketContainer packetContainer) throws IllegalAccessException {
+		Object packet = packetContainer.getHandle();
+		Class<?> clazz = packet.getClass();
+		
+		// Get the first Minecraft super class
+		while (clazz != null && clazz != Object.class &&
+				(!MinecraftReflection.isMinecraftClass(clazz) || 
+				 Factory.class.isAssignableFrom(clazz))) {
+			clazz = clazz.getSuperclass();
+		}
+		
+		return PrettyPrinter.printObject(packet, clazz, MinecraftReflection.getPacketClass(), PrettyPrinter.RECURSE_DEPTH, new ObjectPrinter() {
+			@Override
+			public boolean print(StringBuilder output, Object value) {
+				// Special case
+				if (value instanceof byte[]) {
+					byte[] data = (byte[]) value;
+					
+					if (data.length > HEX_DUMP_THRESHOLD) {
+						output.append("[");
+						HexDumper.defaultDumper().appendTo(output, data);
+						output.append("]");
+						return true;
+					}
+				} else if (value != null) {
+					EquivalentConverter<Object> converter = findConverter(value.getClass());
+
+					if (converter != null) {
+						output.append(converter.getSpecific(value));
+						return true;
+					}
+				}
+				return false;
+			}
+		});
+	}
+	
+	
+	private static EquivalentConverter<Object> findConverter(Class<?> clazz) {
+		Map<Class<?>, EquivalentConverter<Object>> converters = BukkitConverters.getConvertersForGeneric();
+		
+		while (clazz != null) {
+			EquivalentConverter<Object> result = converters.get(clazz);
+			
+			if (result != null)
+				return result;
+			else
+				clazz = clazz.getSuperclass();
+		}
+		return null;
+	}
+
+}