From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Hugo Manrique <hugmanrique@gmail.com>
Date: Mon, 23 Jul 2018 14:22:26 +0200
Subject: [PATCH] Vanished players don't have rights


diff --git a/src/main/java/net/minecraft/server/BlockBase.java b/src/main/java/net/minecraft/server/BlockBase.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/BlockBase.java
+++ b/src/main/java/net/minecraft/server/BlockBase.java
@@ -0,0 +0,0 @@ public abstract class BlockBase {
             return this.a != null ? this.a.b : this.b(iblockaccess, blockposition, VoxelShapeCollision.a());
         }
 
+        public final VoxelShape getCollisionShape(IBlockAccess iblockaccess, BlockPosition blockposition, VoxelShapeCollision voxelshapecollision) { return this.b(iblockaccess, blockposition, voxelshapecollision); } // Paper - OBFHELPER
         public VoxelShape b(IBlockAccess iblockaccess, BlockPosition blockposition, VoxelShapeCollision voxelshapecollision) {
             return this.getBlock().c(this.p(), iblockaccess, blockposition, voxelshapecollision);
         }
diff --git a/src/main/java/net/minecraft/server/Entity.java b/src/main/java/net/minecraft/server/Entity.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/Entity.java
+++ b/src/main/java/net/minecraft/server/Entity.java
@@ -0,0 +0,0 @@ public abstract class Entity implements INamableTileEntity, ICommandListener, Ke
     private static double e = 1.0D;
     private final EntityTypes<?> f;
     private int id;
-    public boolean i;
+    public boolean i; public final boolean blocksEntitySpawning() { return this.i; } // Paper - OBFHELPER
     public final List<Entity> passengers;
     protected int j;
     @Nullable
diff --git a/src/main/java/net/minecraft/server/EntityFireworks.java b/src/main/java/net/minecraft/server/EntityFireworks.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/EntityFireworks.java
+++ b/src/main/java/net/minecraft/server/EntityFireworks.java
@@ -0,0 +0,0 @@ public class EntityFireworks extends IProjectile {
             this.move(EnumMoveType.SELF, vec3d);
             this.setMot(vec3d);
         }
-
         MovingObjectPosition movingobjectposition = ProjectileHelper.a(this, this::a, RayTrace.BlockCollisionOption.COLLIDER);
 
         if (!this.noclip) {
diff --git a/src/main/java/net/minecraft/server/IProjectile.java b/src/main/java/net/minecraft/server/IProjectile.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/IProjectile.java
+++ b/src/main/java/net/minecraft/server/IProjectile.java
@@ -0,0 +0,0 @@ public abstract class IProjectile extends Entity {
     protected boolean a(Entity entity) {
         if (!entity.isSpectator() && entity.isAlive() && entity.isInteractable()) {
             Entity entity1 = this.getShooter();
-
+            // Paper start - Cancel hit for vanished players
+            if (entity1 instanceof EntityPlayer && entity instanceof EntityPlayer) {
+                org.bukkit.entity.Player collided = (org.bukkit.entity.Player) entity.getBukkitEntity();
+                org.bukkit.entity.Player shooter = (org.bukkit.entity.Player) entity1.getBukkitEntity();
+                if (!shooter.canSee(collided)) return false;
+            }
             return entity1 == null || this.d || !entity1.isSameVehicle(entity);
+            // Paper end
         } else {
             return false;
         }
diff --git a/src/main/java/net/minecraft/server/ItemBlock.java b/src/main/java/net/minecraft/server/ItemBlock.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/ItemBlock.java
+++ b/src/main/java/net/minecraft/server/ItemBlock.java
@@ -0,0 +0,0 @@ public class ItemBlock extends Item {
         EntityHuman entityhuman = blockactioncontext.getEntity();
         VoxelShapeCollision voxelshapecollision = entityhuman == null ? VoxelShapeCollision.a() : VoxelShapeCollision.a((Entity) entityhuman);
         // CraftBukkit start - store default return
-        boolean defaultReturn = (!this.isCheckCollisions() || iblockdata.canPlace(blockactioncontext.getWorld(), blockactioncontext.getClickPosition())) && blockactioncontext.getWorld().a(iblockdata, blockactioncontext.getClickPosition(), voxelshapecollision);
+        World world = blockactioncontext.getWorld(); // Paper
+        boolean defaultReturn = (!this.isCheckCollisions() || iblockdata.canPlace(blockactioncontext.getWorld(), blockactioncontext.getClickPosition())) && world.checkEntityCollision(iblockdata, entityhuman, voxelshapecollision, blockactioncontext.getClickPosition(), true); // Paper
         org.bukkit.entity.Player player = (blockactioncontext.getEntity() instanceof EntityPlayer) ? (org.bukkit.entity.Player) blockactioncontext.getEntity().getBukkitEntity() : null;
 
         BlockCanBuildEvent event = new BlockCanBuildEvent(CraftBlock.at(blockactioncontext.getWorld(), blockactioncontext.getClickPosition()), player, CraftBlockData.fromData(iblockdata), defaultReturn);
diff --git a/src/main/java/net/minecraft/server/VoxelShape.java b/src/main/java/net/minecraft/server/VoxelShape.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/VoxelShape.java
+++ b/src/main/java/net/minecraft/server/VoxelShape.java
@@ -0,0 +0,0 @@ public abstract class VoxelShape {
         return this.a.a();
     }
 
+    public final VoxelShape offset(double x, double y, double z) { return this.a(x, y, z); } // Paper - OBFHELPER
     public VoxelShape a(double d0, double d1, double d2) {
         return (VoxelShape) (this.isEmpty() ? VoxelShapes.a() : new VoxelShapeArray(this.a, new DoubleListOffset(this.a(EnumDirection.EnumAxis.X), d0), new DoubleListOffset(this.a(EnumDirection.EnumAxis.Y), d1), new DoubleListOffset(this.a(EnumDirection.EnumAxis.Z), d2)));
     }
diff --git a/src/main/java/net/minecraft/server/VoxelShapes.java b/src/main/java/net/minecraft/server/VoxelShapes.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/VoxelShapes.java
+++ b/src/main/java/net/minecraft/server/VoxelShapes.java
@@ -0,0 +0,0 @@ public final class VoxelShapes {
         return a(new AxisAlignedBB(d0, d1, d2, d3, d4, d5));
     }
 
+    public static final VoxelShape of(AxisAlignedBB axisAlignedbb) { return VoxelShapes.a(axisAlignedbb); } // Paper - OBFHELPER
     public static VoxelShape a(AxisAlignedBB axisalignedbb) {
         int i = a(axisalignedbb.minX, axisalignedbb.maxX);
         int j = a(axisalignedbb.minY, axisalignedbb.maxY);
@@ -0,0 +0,0 @@ public final class VoxelShapes {
         }
     }
 
+    public static final boolean applyOperation(VoxelShape voxelshape, VoxelShape voxelshape1, OperatorBoolean operatorboolean) { return VoxelShapes.c(voxelshape, voxelshape1, operatorboolean); } // Paper - OBFHELPER
     public static boolean c(VoxelShape voxelshape, VoxelShape voxelshape1, OperatorBoolean operatorboolean) {
         if (operatorboolean.apply(false, false)) {
             throw (IllegalArgumentException) SystemUtils.c(new IllegalArgumentException());
diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -0,0 +0,0 @@ public abstract class World implements GeneratorAccess, AutoCloseable {
         this.tileLimiter = new org.spigotmc.TickLimiter(spigotConfig.tileMaxTickTime);
     }
 
+    // Paper start
+    // ret true if no collision
+    public final boolean checkEntityCollision(IBlockData data, Entity source, VoxelShapeCollision voxelshapedcollision,
+                                              BlockPosition position, boolean checkCanSee) {
+        // Copied from IWorldReader#a(IBlockData, BlockPosition, VoxelShapeCollision) & EntityAccess#a(Entity, VoxelShape)
+        VoxelShape voxelshape = data.getCollisionShape(this, position, voxelshapedcollision);
+        if (voxelshape.isEmpty()) {
+            return true;
+        }
+
+        voxelshape = voxelshape.offset((double) position.getX(), (double) position.getY(), (double) position.getZ());
+        if (voxelshape.isEmpty()) {
+            return true;
+        }
+
+        List<Entity> entities = this.getEntities(null, voxelshape.getBoundingBox());
+        for (int i = 0, len = entities.size(); i < len; ++i) {
+            Entity entity = entities.get(i);
+
+            if (checkCanSee && source instanceof EntityPlayer && entity instanceof EntityPlayer
+                && !((EntityPlayer) source).getBukkitEntity().canSee(((EntityPlayer) entity).getBukkitEntity())) {
+                continue;
+            }
+
+            // !entity1.dead && entity1.i && (entity == null || !entity1.x(entity));
+            // elide the last check since vanilla calls with entity = null
+            // only we care about the source for the canSee check
+            if (entity.dead || !entity.blocksEntitySpawning()) {
+                continue;
+            }
+
+            if (VoxelShapes.applyOperation(voxelshape, VoxelShapes.of(entity.getBoundingBox()), OperatorBoolean.AND)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+    // Paper end
+
     @Override
     public boolean s_() {
         return this.isClientSide;
diff --git a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
+++ b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
@@ -0,0 +0,0 @@ public class CraftEventFactory {
         Projectile projectile = (Projectile) entity.getBukkitEntity();
         org.bukkit.entity.Entity collided = position.getEntity().getBukkitEntity();
         com.destroystokyo.paper.event.entity.ProjectileCollideEvent event = new com.destroystokyo.paper.event.entity.ProjectileCollideEvent(projectile, collided);
+
+        if (projectile.getShooter() instanceof Player && collided instanceof Player) {
+            if (!((Player) projectile.getShooter()).canSee((Player) collided)) {
+                event.setCancelled(true);
+                return event;
+            }
+        }
+
         Bukkit.getPluginManager().callEvent(event);
         return event;
     }
