#642: Add a DragonBattle API to manipulate respawn phases etc

By: Parker Hawke <hawkeboyz2@hotmail.com>

paper-server/src/main/java/org/bukkit/craftbukkit/CraftWorld.java

@@ -88,6 +88,8 @@ import net.minecraft.server.TicketType;
 import net.minecraft.server.Unit;
 import net.minecraft.server.Vec3D;
 import net.minecraft.server.WorldGenerator;
+import net.minecraft.server.WorldProvider;
+import net.minecraft.server.WorldProviderTheEnd;
 import net.minecraft.server.WorldServer;
 import org.apache.commons.lang.Validate;
 import org.bukkit.BlockChangeDelegate;
@@ -111,9 +113,11 @@ import org.bukkit.block.Block;
 import org.bukkit.block.BlockFace;
 import org.bukkit.block.BlockState;
 import org.bukkit.block.data.BlockData;
+import org.bukkit.boss.DragonBattle;
 import org.bukkit.craftbukkit.block.CraftBlock;
 import org.bukkit.craftbukkit.block.CraftBlockState;
 import org.bukkit.craftbukkit.block.data.CraftBlockData;
+import org.bukkit.craftbukkit.boss.CraftDragonBattle;
 import org.bukkit.craftbukkit.entity.CraftEntity;
 import org.bukkit.craftbukkit.entity.CraftItem;
 import org.bukkit.craftbukkit.entity.CraftLightningStrike;
@@ -2270,4 +2274,14 @@ public class CraftWorld implements World {
         PersistentRaid persistentRaid = world.getPersistentRaid();
         return persistentRaid.raids.values().stream().map(CraftRaid::new).collect(Collectors.toList());
     }
+
+    @Override
+    public DragonBattle getEnderDragonBattle() {
+        WorldProvider worldProvider = getHandle().worldProvider;
+        if (!(worldProvider instanceof WorldProviderTheEnd)) {
+            return null;
+        }
+
+        return new CraftDragonBattle(((WorldProviderTheEnd) worldProvider).o()); // PAIL rename getDragonBattle
+    }
 }

paper-server/src/main/java/org/bukkit/craftbukkit/boss/CraftDragonBattle.java

@@ -0,0 +1,85 @@
+package org.bukkit.craftbukkit.boss;
+
+import com.google.common.base.Preconditions;
+import net.minecraft.server.EnderDragonBattle;
+import net.minecraft.server.Entity;
+import net.minecraft.server.EnumDragonRespawn;
+import org.bukkit.Location;
+import org.bukkit.boss.BossBar;
+import org.bukkit.boss.DragonBattle;
+import org.bukkit.entity.EnderDragon;
+
+public class CraftDragonBattle implements DragonBattle {
+
+    private final EnderDragonBattle handle;
+
+    public CraftDragonBattle(EnderDragonBattle handle) {
+        this.handle = handle;
+    }
+
+    @Override
+    public EnderDragon getEnderDragon() {
+        Entity entity = handle.d.getEntity(handle.m);
+        return (entity != null) ? (EnderDragon) entity.getBukkitEntity() : null;
+    }
+
+    @Override
+    public BossBar getBossBar() {
+        return new CraftBossBar(handle.bossBattle);
+    }
+
+    @Override
+    public Location getEndPortalLocation() {
+        return new Location(handle.d.getWorld(), handle.o.getX(), handle.o.getY(), handle.o.getZ());
+    }
+
+    @Override
+    public boolean hasBeenPreviouslyKilled() {
+        return handle.d(); // PAIL rename hasBeenPreviouslyKilled
+    }
+
+    @Override
+    public void initiateRespawn() {
+        this.handle.e(); // PAIL rename initiateRespawn
+    }
+
+    @Override
+    public RespawnPhase getRespawnPhase() {
+        return toBukkitRespawnPhase(handle.p);
+    }
+
+    @Override
+    public boolean setRespawnPhase(RespawnPhase phase) {
+        Preconditions.checkArgument(phase != null && phase != RespawnPhase.NONE, "Invalid respawn phase provided: %s", phase);
+
+        if (handle.p == null) {
+            return false;
+        }
+
+        this.handle.a(toNMSRespawnPhase(phase));
+        return true;
+    }
+
+    @Override
+    public void resetCrystals() {
+        this.handle.f(); // PAIL rename resetCrystals
+    }
+
+    @Override
+    public int hashCode() {
+        return handle.hashCode();
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        return obj instanceof CraftDragonBattle && ((CraftDragonBattle) obj).handle == this.handle;
+    }
+
+    private RespawnPhase toBukkitRespawnPhase(EnumDragonRespawn phase) {
+        return (phase != null) ? RespawnPhase.values()[phase.ordinal()] : RespawnPhase.NONE;
+    }
+
+    private EnumDragonRespawn toNMSRespawnPhase(RespawnPhase phase) {
+        return (phase != RespawnPhase.NONE) ? EnumDragonRespawn.values()[phase.ordinal()] : null;
+    }
+}

paper-server/src/main/java/org/bukkit/craftbukkit/entity/CraftEnderDragon.java

@@ -7,22 +7,18 @@ import net.minecraft.server.DragonControllerPhase;
 import net.minecraft.server.EntityComplexPart;
 import net.minecraft.server.EntityEnderDragon;
 import org.bukkit.boss.BossBar;
+import org.bukkit.boss.DragonBattle;
 import org.bukkit.craftbukkit.CraftServer;
 import org.bukkit.craftbukkit.boss.CraftBossBar;
+import org.bukkit.craftbukkit.boss.CraftDragonBattle;
 import org.bukkit.entity.ComplexEntityPart;
 import org.bukkit.entity.EnderDragon;
 import org.bukkit.entity.EntityType;
 
 public class CraftEnderDragon extends CraftComplexLivingEntity implements EnderDragon {
 
-    private BossBar bossBar;
-
     public CraftEnderDragon(CraftServer server, EntityEnderDragon entity) {
         super(server, entity);
-
-        if (entity.getEnderDragonBattle() != null) {
-            this.bossBar = new CraftBossBar(entity.getEnderDragonBattle().bossBattle);
-        }
     }
 
     @Override
@@ -71,6 +67,16 @@ public class CraftEnderDragon extends CraftComplexLivingEntity implements EnderD
 
     @Override
     public BossBar getBossBar() {
-        return bossBar;
+        return getDragonBattle().getBossBar();
+    }
+
+    @Override
+    public DragonBattle getDragonBattle() {
+        return new CraftDragonBattle(getHandle().getEnderDragonBattle());
+    }
+
+    @Override
+    public int getDeathAnimationTicks() {
+        return getHandle().bA; // PAIL rename deathAnimationTicks
     }
 }