PaperMC/paper-server/patches/sources/net/minecraft/world/entity/ExperienceOrb.java.patch

--- a/net/minecraft/world/entity/ExperienceOrb.java
+++ b/net/minecraft/world/entity/ExperienceOrb.java
@@ -24,6 +24,13 @@
 import net.minecraft.world.level.entity.EntityTypeTest;
 import net.minecraft.world.phys.AABB;
 import net.minecraft.world.phys.Vec3;
+// CraftBukkit start
+import org.bukkit.craftbukkit.event.CraftEventFactory;
+import org.bukkit.event.entity.EntityRemoveEvent;
+import org.bukkit.event.entity.EntityTargetLivingEntityEvent;
+import org.bukkit.event.entity.EntityTargetEvent;
+import org.bukkit.event.player.PlayerExpCooldownChangeEvent;
+// CraftBukkit end
 
 public class ExperienceOrb extends Entity {
 
@@ -37,9 +44,63 @@
     public int value;
     public int count;
     private Player followingPlayer;
+    // Paper start
+    @javax.annotation.Nullable
+    public java.util.UUID sourceEntityId;
+    @javax.annotation.Nullable
+    public java.util.UUID triggerEntityId;
+    public org.bukkit.entity.ExperienceOrb.SpawnReason spawnReason = org.bukkit.entity.ExperienceOrb.SpawnReason.UNKNOWN;
 
+    private void loadPaperNBT(CompoundTag tag) {
+        if (!tag.contains("Paper.ExpData", net.minecraft.nbt.Tag.TAG_COMPOUND)) {
+            return;
+        }
+        CompoundTag comp = tag.getCompound("Paper.ExpData");
+        if (comp.hasUUID("source")) {
+            this.sourceEntityId = comp.getUUID("source");
+        }
+        if (comp.hasUUID("trigger")) {
+            this.triggerEntityId = comp.getUUID("trigger");
+        }
+        if (comp.contains("reason")) {
+            String reason = comp.getString("reason");
+            try {
+                this.spawnReason = org.bukkit.entity.ExperienceOrb.SpawnReason.valueOf(reason);
+            } catch (Exception e) {
+                this.level().getCraftServer().getLogger().warning("Invalid spawnReason set for experience orb: " + e.getMessage() + " - " + reason);
+            }
+        }
+    }
+    private void savePaperNBT(CompoundTag tag) {
+        CompoundTag comp = new CompoundTag();
+        if (this.sourceEntityId != null) {
+            comp.putUUID("source", this.sourceEntityId);
+        }
+        if (this.triggerEntityId != null) {
+            comp.putUUID("trigger", triggerEntityId);
+        }
+        if (this.spawnReason != null && this.spawnReason != org.bukkit.entity.ExperienceOrb.SpawnReason.UNKNOWN) {
+            comp.putString("reason", this.spawnReason.name());
+        }
+        tag.put("Paper.ExpData", comp);
+    }
+
+    @io.papermc.paper.annotation.DoNotUse
+    @Deprecated
     public ExperienceOrb(Level world, double x, double y, double z, int amount) {
+        this(world, x, y, z, amount, null, null);
+    }
+
+    public ExperienceOrb(Level world, double x, double y, double z, int amount, @javax.annotation.Nullable org.bukkit.entity.ExperienceOrb.SpawnReason reason, @javax.annotation.Nullable Entity triggerId) {
+        this(world, x, y, z, amount, reason, triggerId, null);
+    }
+
+    public ExperienceOrb(Level world, double x, double y, double z, int amount, @javax.annotation.Nullable org.bukkit.entity.ExperienceOrb.SpawnReason reason, @javax.annotation.Nullable Entity triggerId, @javax.annotation.Nullable Entity sourceId) {
         this(EntityType.EXPERIENCE_ORB, world);
+        this.sourceEntityId = sourceId != null ? sourceId.getUUID() : null;
+        this.triggerEntityId = triggerId != null ? triggerId.getUUID() : null;
+        this.spawnReason = reason != null ? reason : org.bukkit.entity.ExperienceOrb.SpawnReason.UNKNOWN;
+        // Paper end
         this.setPos(x, y, z);
         this.setYRot((float) (this.random.nextDouble() * 360.0D));
         this.setDeltaMovement((this.random.nextDouble() * 0.20000000298023224D - 0.10000000149011612D) * 2.0D, this.random.nextDouble() * 0.2D * 2.0D, (this.random.nextDouble() * 0.20000000298023224D - 0.10000000149011612D) * 2.0D);
@@ -68,6 +129,7 @@
     @Override
     public void tick() {
         super.tick();
+        Player prevTarget = this.followingPlayer;// CraftBukkit - store old target
         this.xo = this.getX();
         this.yo = this.getY();
         this.zo = this.getZ();
@@ -93,7 +155,22 @@
             this.followingPlayer = null;
         }
 
-        if (this.followingPlayer != null) {
+        // CraftBukkit start
+        boolean cancelled = false;
+        if (this.followingPlayer != prevTarget) {
+            EntityTargetLivingEntityEvent event = CraftEventFactory.callEntityTargetLivingEvent(this, this.followingPlayer, (this.followingPlayer != null) ? EntityTargetEvent.TargetReason.CLOSEST_PLAYER : EntityTargetEvent.TargetReason.FORGOT_TARGET);
+            LivingEntity target = (event.getTarget() == null) ? null : ((org.bukkit.craftbukkit.entity.CraftLivingEntity) event.getTarget()).getHandle();
+            cancelled = event.isCancelled();
+
+            if (cancelled) {
+                this.followingPlayer = prevTarget;
+            } else {
+                this.followingPlayer = (target instanceof Player) ? (Player) target : null;
+            }
+        }
+
+        if (this.followingPlayer != null && !cancelled) {
+            // CraftBukkit end
             Vec3 vec3d = new Vec3(this.followingPlayer.getX() - this.getX(), this.followingPlayer.getY() + (double) this.followingPlayer.getEyeHeight() / 2.0D - this.getY(), this.followingPlayer.getZ() - this.getZ());
             double d0 = vec3d.lengthSqr();
 
@@ -121,7 +198,7 @@
 
         ++this.age;
         if (this.age >= 6000) {
-            this.discard();
+            this.discard(EntityRemoveEvent.Cause.DESPAWN); // CraftBukkit - add Bukkit remove cause
         }
 
     }
@@ -150,18 +227,27 @@
     }
 
     public static void award(ServerLevel world, Vec3 pos, int amount) {
+        // Paper start - add reasons for orbs
+        award(world, pos, amount, null, null, null);
+    }
+    public static void award(ServerLevel world, Vec3 pos, int amount, org.bukkit.entity.ExperienceOrb.SpawnReason reason, Entity triggerId) {
+        award(world, pos, amount, reason, triggerId, null);
+    }
+    public static void award(ServerLevel world, Vec3 pos, int amount, org.bukkit.entity.ExperienceOrb.SpawnReason reason, Entity triggerId, Entity sourceId) {
+        // Paper end - add reasons for orbs
         while (amount > 0) {
             int j = ExperienceOrb.getExperienceValue(amount);
 
             amount -= j;
             if (!ExperienceOrb.tryMergeToExisting(world, pos, j)) {
-                world.addFreshEntity(new ExperienceOrb(world, pos.x(), pos.y(), pos.z(), j));
+                world.addFreshEntity(new ExperienceOrb(world, pos.x(), pos.y(), pos.z(), j, reason, triggerId, sourceId)); // Paper - add reason
             }
         }
 
     }
 
     private static boolean tryMergeToExisting(ServerLevel world, Vec3 pos, int amount) {
+        // Paper - TODO some other event for this kind of merge
         AABB axisalignedbb = AABB.ofSize(pos, 1.0D, 1.0D, 1.0D);
         int j = world.getRandom().nextInt(40);
         List<ExperienceOrb> list = world.getEntities(EntityTypeTest.forClass(ExperienceOrb.class), axisalignedbb, (entityexperienceorb) -> {
@@ -188,9 +274,14 @@
     }
 
     private void merge(ExperienceOrb other) {
+        // Paper start - call orb merge event
+        if (!new com.destroystokyo.paper.event.entity.ExperienceOrbMergeEvent((org.bukkit.entity.ExperienceOrb) this.getBukkitEntity(), (org.bukkit.entity.ExperienceOrb) other.getBukkitEntity()).callEvent()) {
+            return;
+        }
+        // Paper end - call orb merge event
         this.count += other.count;
         this.age = Math.min(this.age, other.age);
-        other.discard();
+        other.discard(EntityRemoveEvent.Cause.MERGE); // CraftBukkit - add Bukkit remove cause
     }
 
     private void setUnderwaterMovement() {
@@ -215,7 +306,7 @@
             this.markHurt();
             this.health = (int) ((float) this.health - amount);
             if (this.health <= 0) {
-                this.discard();
+                this.discard(EntityRemoveEvent.Cause.DEATH); // CraftBukkit - add Bukkit remove cause
             }
 
             return true;
@@ -226,33 +317,35 @@
     public void addAdditionalSaveData(CompoundTag nbt) {
         nbt.putShort("Health", (short) this.health);
         nbt.putShort("Age", (short) this.age);
-        nbt.putShort("Value", (short) this.value);
+        nbt.putInt("Value", this.value); // Paper - save as Integer
         nbt.putInt("Count", this.count);
+        this.savePaperNBT(nbt); // Paper
     }
 
     @Override
     public void readAdditionalSaveData(CompoundTag nbt) {
         this.health = nbt.getShort("Health");
         this.age = nbt.getShort("Age");
-        this.value = nbt.getShort("Value");
+        this.value = nbt.getInt("Value"); // Paper - load as Integer
         this.count = Math.max(nbt.getInt("Count"), 1);
+        this.loadPaperNBT(nbt); // Paper
     }
 
     @Override
     public void playerTouch(Player player) {
         if (player instanceof ServerPlayer entityplayer) {
-            if (player.takeXpDelay == 0) {
-                player.takeXpDelay = 2;
+            if (player.takeXpDelay == 0 && new com.destroystokyo.paper.event.player.PlayerPickupExperienceEvent(entityplayer.getBukkitEntity(), (org.bukkit.entity.ExperienceOrb) this.getBukkitEntity()).callEvent()) { // Paper - PlayerPickupExperienceEvent
+                player.takeXpDelay = CraftEventFactory.callPlayerXpCooldownEvent(player, 2, PlayerExpCooldownChangeEvent.ChangeReason.PICKUP_ORB).getNewCooldown(); // CraftBukkit - entityhuman.takeXpDelay = 2;
                 player.take(this, 1);
                 int i = this.repairPlayerItems(entityplayer, this.value);
 
                 if (i > 0) {
-                    player.giveExperiencePoints(i);
+                    player.giveExperiencePoints(CraftEventFactory.callPlayerExpChangeEvent(player, this).getAmount()); // CraftBukkit - this.value -> event.getAmount() // Paper - supply experience orb object
                 }
 
                 --this.count;
                 if (this.count == 0) {
-                    this.discard();
+                    this.discard(EntityRemoveEvent.Cause.PICKUP); // CraftBukkit - add Bukkit remove cause
                 }
             }
 
@@ -266,12 +359,23 @@
             ItemStack itemstack = ((EnchantedItemInUse) optional.get()).itemStack();
             int j = EnchantmentHelper.modifyDurabilityToRepairFromXp(player.serverLevel(), itemstack, amount);
             int k = Math.min(j, itemstack.getDamageValue());
+            // CraftBukkit start
+            // Paper start - mending event
+            final int consumedExperience = k > 0 ? k * amount / j : 0;
+            org.bukkit.event.player.PlayerItemMendEvent event = CraftEventFactory.callPlayerItemMendEvent(player, this, itemstack, optional.get().inSlot(), k, consumedExperience);
+            // Paper end - mending event
+            k = event.getRepairAmount();
+            if (event.isCancelled()) {
+                return amount;
+            }
+            // CraftBukkit end
 
             itemstack.setDamageValue(itemstack.getDamageValue() - k);
             if (k > 0) {
-                int l = amount - k * amount / j;
+                int l = amount - k * amount / j; // Paper - diff on change - expand PlayerMendEvents
 
                 if (l > 0) {
+                    // this.value = l; // CraftBukkit - update exp value of orb for PlayerItemMendEvent calls // Paper - the value field should not be mutated here because it doesn't take "count" into account
                     return this.repairPlayerItems(player, l);
                 }
             }
@@ -291,6 +395,24 @@
     }
 
     public static int getExperienceValue(int value) {
+        // CraftBukkit start
+        if (value > 162670129) return value - 100000;
+        if (value > 81335063) return 81335063;
+        if (value > 40667527) return 40667527;
+        if (value > 20333759) return 20333759;
+        if (value > 10166857) return 10166857;
+        if (value > 5083423) return 5083423;
+        if (value > 2541701) return 2541701;
+        if (value > 1270849) return 1270849;
+        if (value > 635413) return 635413;
+        if (value > 317701) return 317701;
+        if (value > 158849) return 158849;
+        if (value > 79423) return 79423;
+        if (value > 39709) return 39709;
+        if (value > 19853) return 19853;
+        if (value > 9923) return 9923;
+        if (value > 4957) return 4957;
+        // CraftBukkit end
         return value >= 2477 ? 2477 : (value >= 1237 ? 1237 : (value >= 617 ? 617 : (value >= 307 ? 307 : (value >= 149 ? 149 : (value >= 73 ? 73 : (value >= 37 ? 37 : (value >= 17 ? 17 : (value >= 7 ? 7 : (value >= 3 ? 3 : 1)))))))));
     }