package the.brawl.main.util;
import org.bukkit.Bukkit;
import org.bukkit.Location;
import org.bukkit.craftbukkit.v1_10_R1.CraftWorld;
import org.bukkit.entity.Player;
public class Hologram {
// Line spacing (0.23D default)
private static final double offset = 0.23D;
// CB Version string
private static String version;
private String[] lines;
private Location location;
static {
version = Bukkit.getServer().getClass().getPackage().getName().replace(".", ",").split(",")[3] + ".";
}
/**
* Create a new Hologram at the specified Location, with the text #Lines#
* @param location
* @param lines
*/
public Hologram(Location location, String... lines) {
this.lines = lines;
this.location = location;
}
/**
* Returns true if it displays.
* @param player - The player to display it to.
* @return
*/
public boolean showPlayer(Player player) {
Location display = location.clone().add(0, (offset * lines.length) - 1.97D, 0);
for (String line : lines) {
Object packet = this.getPacket(display, line);
if (packet == null)
return false;
sendPacket(player, packet);
display.add(0, -offset, 0);
}
return true;
}
public void showGlobal() {
Location display = location.clone().add(0, (offset * lines.length) - 1.97D, 0);
for (String line : lines) {
show(display, line);
display.add(0, -offset, 0);
}
}
/**
* Get the packet for creating a new Hologram, using EntityArmorStands and PacketPlayOutSpawnEntityLiving
* @param location - The location for which to spawn the hologram.
* @param text - The text (entity name) of the hologram.
* @return Object - The PacketPlayOutSpawnEntityLiving packet in the form of an Object (Because of reflection, duh ^^)
*/
private Object getPacket(Location location, String text) {
try {
Object craftWorldObj = getClass("CraftWorld", true).cast(location.getWorld());
Object entityObject = getClass("EntityArmorStand", false).getConstructor(getClass("World", false)).newInstance(craftWorldObj.getClass().getMethod("getHandle").invoke(craftWorldObj));
entityObject.getClass().getMethod("setCustomName", String.class).invoke(entityObject, text);
entityObject.getClass().getMethod("setCustomNameVisible", boolean.class).invoke(entityObject, true);
entityObject.getClass().getMethod("setNoGravity", boolean.class).invoke(entityObject, true); // Previously setGravity(boolean)
entityObject.getClass().getMethod("setLocation", double.class, double.class, double.class, float.class, float.class).invoke(entityObject, location.getX(), location.getY(), location.getZ(), 0.0F, 0.0F);
entityObject.getClass().getField("collides").setAccessible(true);
entityObject.getClass().getField("collides").setBoolean(entityObject, false);
entityObject.getClass().getField("collides").setAccessible(false);
entityObject.getClass().getMethod("setInvisible", boolean.class).invoke(entityObject, true);
return getClass("PacketPlayOutSpawnEntityLiving", false).getConstructor(getClass("EntityLiving", false)).newInstance(entityObject);
} catch (Exception ex) {
ex.printStackTrace();
return null;
}
}
/**
* Spawn the hologram for everyone to see.
* @param location - The location to spawn the hologram.
* @param text - The text to display with the hologram.
*/
private void show(Location location, String text) {
try {
Object craftWorldObj = getClass("CraftWorld", true).cast(location.getWorld());
Object entityObject = getClass("EntityArmorStand", false).getConstructor(getClass("World", false)).newInstance(craftWorldObj.getClass().getMethod("getHandle").invoke(craftWorldObj));
// Temporarily Broken
//craftWorldObj.getClass().getMethod("spawn", )).invoke(craftWorldObj, entityObject);
entityObject.getClass().getMethod("setCustomName", String.class).invoke(entityObject, text);
entityObject.getClass().getMethod("setCustomNameVisible", boolean.class).invoke(entityObject, true);
entityObject.getClass().getMethod("setNoGravity", boolean.class).invoke(entityObject, true); // Previously setGravity(boolean)
entityObject.getClass().getMethod("setLocation", double.class, double.class, double.class, float.class, float.class).invoke(entityObject, location.getX(), location.getY(), location.getZ(), 0.0F, 0.0F);
entityObject.getClass().getField("collides").setAccessible(true);
entityObject.getClass().getField("collides").setBoolean(entityObject, false);
entityObject.getClass().getField("collides").setAccessible(false);
entityObject.getClass().getMethod("setInvisible", boolean.class).invoke(entityObject, true);
} catch (Exception ex) {
ex.printStackTrace();
}
}
/**
* Send the packet to a player.
* @param player
* @param packet
*/
private void sendPacket(Player player, Object packet) {
try {
Object entityPlayer = player.getClass().getMethod("getHandle").invoke(player);
Object connection = entityPlayer.getClass().getField("playerConnection").get(entityPlayer);
connection.getClass().getMethod("sendPacket", getClass("Packet", false)).invoke(connection, packet);
} catch (Exception ex) {
ex.printStackTrace();
}
}
/**
* Returns a specific CraftBukkit or net.minecraft.server class.
* @param name
* @param craftbukkit
* @return
*/
private Class<?> getClass(String name, boolean craftbukkit) throws ClassNotFoundException {
return Class.forName((craftbukkit ? "org.bukkit.craftbukkit." : "net.minecraft.server.") + version + (name.startsWith(".") ? name.substring(1) : name));
}
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