From 940c75c0c08c0e3c92926e372f40d310fb0a6e52 Mon Sep 17 00:00:00 2001
From: Zach Brown <zach.brown@destroystokyo.com>
Date: Fri, 16 Dec 2016 22:10:35 -0600
Subject: [PATCH] Vanished players don't have rights


diff --git a/src/main/java/net/minecraft/server/Entity.java b/src/main/java/net/minecraft/server/Entity.java
index 9be8c6ff5..09b2042e1 100644
--- a/src/main/java/net/minecraft/server/Entity.java
+++ b/src/main/java/net/minecraft/server/Entity.java
@@ -68,7 +68,7 @@ public abstract class Entity implements ICommandListener {
     private static double f = 1.0D;
     private static int entityCount;
     private int id;
-    public boolean i;
+    public boolean i; public boolean blocksEntitySpawning() { return i; } // Paper - OBFHELPER
     public final List<Entity> passengers;
     protected int j;
     private Entity au;public void setVehicle(Entity entity) { this.au = entity; } // Paper // OBFHELPER
diff --git a/src/main/java/net/minecraft/server/ItemBlock.java b/src/main/java/net/minecraft/server/ItemBlock.java
index c0d97f154..363209170 100644
--- a/src/main/java/net/minecraft/server/ItemBlock.java
+++ b/src/main/java/net/minecraft/server/ItemBlock.java
@@ -20,7 +20,7 @@ public class ItemBlock extends Item {
 
         ItemStack itemstack = entityhuman.b(enumhand);
 
-        if (!itemstack.isEmpty() && entityhuman.a(blockposition, enumdirection, itemstack) && world.a(this.a, blockposition, false, enumdirection, (Entity) null)) {
+        if (!itemstack.isEmpty() && entityhuman.a(blockposition, enumdirection, itemstack) && world.a(this.a, blockposition, false, enumdirection, entityhuman)) { // Paper - Pass entityhuman instead of null
             int i = this.filterData(itemstack.getData());
             IBlockData iblockdata1 = this.a.getPlacedState(world, blockposition, enumdirection, f, f1, f2, i, entityhuman);
 
diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index 391282afc..b4ef1d6af 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -1806,6 +1806,33 @@ public abstract class World implements IBlockAccess {
         return this.a(axisalignedbb, (Entity) null);
     }
 
+    // Paper start - Based on method below
+    /**
+     * @param axisalignedbb area to search within
+     * @param entity causing the action ex. block placer
+     * @return if there are no visible players colliding
+     */
+    public boolean checkNoVisiblePlayerCollisions(AxisAlignedBB axisalignedbb, @Nullable Entity entity) {
+        List list = this.getEntities((Entity) null, axisalignedbb);
+
+        for (int i = 0; i < list.size(); ++i) {
+            Entity entity1 = (Entity) list.get(i);
+
+            if (entity instanceof EntityPlayer && entity1 instanceof EntityPlayer) {
+                if (!((EntityPlayer) entity).getBukkitEntity().canSee(((EntityPlayer) entity1).getBukkitEntity())) {
+                    continue;
+                }
+            }
+
+            if (!entity1.dead && entity1.blocksEntitySpawning()) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+    // Paper end
+
     public boolean a(AxisAlignedBB axisalignedbb, @Nullable Entity entity) {
         List list = this.getEntities((Entity) null, axisalignedbb);
 
@@ -2696,7 +2723,7 @@ public abstract class World implements IBlockAccess {
         AxisAlignedBB axisalignedbb = flag ? null : block.getBlockData().d(this, blockposition);
 
         // CraftBukkit start - store default return
-        boolean defaultReturn = axisalignedbb != Block.k && !this.a(axisalignedbb.a(blockposition), entity) ? false : (iblockdata.getMaterial() == Material.ORIENTABLE && block == Blocks.ANVIL ? true : iblockdata.getMaterial().isReplaceable() && block.canPlace(this, blockposition, enumdirection));
+        boolean defaultReturn = axisalignedbb != Block.k && !this.checkNoVisiblePlayerCollisions(axisalignedbb.a(blockposition), entity) ? false : (iblockdata.getMaterial() == Material.ORIENTABLE && block == Blocks.ANVIL ? true : iblockdata.getMaterial().isReplaceable() && block.canPlace(this, blockposition, enumdirection)); // Paper - Use our entity search
         BlockCanBuildEvent event = new BlockCanBuildEvent(this.getWorld().getBlockAt(blockposition.getX(), blockposition.getY(), blockposition.getZ()), CraftMagicNumbers.getId(block), defaultReturn);
         this.getServer().getPluginManager().callEvent(event);
 
diff --git a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
index 09f009522..2596c2fa0 100644
--- a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
+++ b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
@@ -799,6 +799,13 @@ public class CraftEventFactory {
         Projectile projectile = (Projectile) entity.getBukkitEntity();
         org.bukkit.entity.Entity collided = position.entity.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);
+            }
+        }
+
         Bukkit.getPluginManager().callEvent(event);
         return event;
     }
-- 
2.13.0