Fix ConcurrentModificatonException in NetworkEventBus (#3660)

* Fixes crash when either quartz types are disabled and prevent cascading worldgen.
* Also fixes  #3486

src/main/java/appeng/block/storage/BlockDrive.java

@@ -74,13 +74,8 @@ public class BlockDrive extends AEBaseTileBlock
 	public IBlockState getExtendedState( IBlockState state, IBlockAccess world, BlockPos pos )
 	{
 		TileDrive te = this.getTileEntity( world, pos );
-		if( te == null )
-		{
-			return super.getExtendedState( state, world, pos );
-		}
-
 		IExtendedBlockState extState = (IExtendedBlockState) super.getExtendedState( state, world, pos );
-		return extState.withProperty( SLOTS_STATE, DriveSlotsState.fromChestOrDrive( te ) );
+		return extState.withProperty( SLOTS_STATE, te == null ? DriveSlotsState.createEmpty( 10 ) : DriveSlotsState.fromChestOrDrive( te ) );
 	}
 
 	@Override

src/main/java/appeng/block/storage/DriveSlotsState.java

@@ -75,4 +75,14 @@ public class DriveSlotsState
 		}
 		return new DriveSlotsState( slots );
 	}
+
+	public static DriveSlotsState createEmpty( int slotCount )
+	{
+		DriveSlotState[] slots = new DriveSlotState[slotCount];
+		for( int i = 0; i < slotCount; i++ )
+		{
+			slots[i] = DriveSlotState.EMPTY;
+		}
+		return new DriveSlotsState( slots );
+	}
 }

src/main/java/appeng/container/AEBaseContainer.java

@@ -436,6 +436,8 @@ public abstract class AEBaseContainer extends Container
 			}
 			else
 			{
+				tis = tis.copy();
+
 				// target slots in the container...
 				for( final Object inventorySlot : this.inventorySlots )
 				{
@@ -496,7 +498,7 @@ public abstract class AEBaseContainer extends Container
 					{
 						if( d.getHasStack() )
 						{
-							final ItemStack t = d.getStack();
+							final ItemStack t = d.getStack().copy();
 
 							if( Platform.itemComparisons().isSameItem( tis, t ) ) // t.isItemEqual(tis))
 							{
@@ -516,6 +518,8 @@ public abstract class AEBaseContainer extends Container
 								t.setCount( t.getCount() + placeAble );
 								tis.setCount( tis.getCount() - placeAble );
 
+								d.putStack( t );
+
 								if( tis.getCount() <= 0 )
 								{
 									clickSlot.putStack( ItemStack.EMPTY );
@@ -548,7 +552,7 @@ public abstract class AEBaseContainer extends Container
 					{
 						if( d.getHasStack() )
 						{
-							final ItemStack t = d.getStack();
+							final ItemStack t = d.getStack().copy();
 
 							if( Platform.itemComparisons().isSameItem( t, tis ) )
 							{
@@ -568,6 +572,8 @@ public abstract class AEBaseContainer extends Container
 								t.setCount( t.getCount() + placeAble );
 								tis.setCount( tis.getCount() - placeAble );
 
+								d.putStack( t );
+
 								if( tis.getCount() <= 0 )
 								{
 									clickSlot.putStack( ItemStack.EMPTY );
@@ -626,7 +632,7 @@ public abstract class AEBaseContainer extends Container
 				}
 			}
 
-			clickSlot.putStack( !tis.isEmpty() ? tis.copy() : ItemStack.EMPTY );
+			clickSlot.putStack( !tis.isEmpty() ? tis : ItemStack.EMPTY );
 		}
 
 		this.updateSlot( clickSlot );

src/main/java/appeng/decorative/solid/BlockQuartzOre.java

@@ -27,6 +27,7 @@ import net.minecraft.item.Item;
 import net.minecraft.util.BlockRenderLayer;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.MathHelper;
+import net.minecraft.world.IBlockAccess;
 import net.minecraft.world.World;
 
 import appeng.api.AEApi;
@@ -76,16 +77,15 @@ public class BlockQuartzOre extends AEBaseBlock
 	}
 
 	@Override
-	public void dropBlockAsItemWithChance( final World w, final BlockPos pos, final IBlockState state, final float chance, final int fortune )
+	public int getExpDrop( IBlockState state, IBlockAccess world, BlockPos pos, int fortune )
 	{
-		super.dropBlockAsItemWithChance( w, pos, state, chance, fortune );
+		Random rand = world instanceof World ? ( (World) world ).rand : new Random();
 	
-		if( this.getItemDropped( state, w.rand, fortune ) != Item.getItemFromBlock( this ) )
+	    if ( this.getItemDropped( state, rand, fortune ) != Item.getItemFromBlock( this ) )  
-		{
+	    {
-			final int xp = MathHelper.getInt( w.rand, 2, 5 );
+			return MathHelper.getInt( rand, 2, 5 );
-
-			this.dropXpOnBlockBreak( w, pos, xp );
 		}
+		return super.getExpDrop( state, world, pos, fortune );
 	}
 
 	@Override

src/main/java/appeng/items/tools/ToolNetworkTool.java

@@ -83,16 +83,9 @@ public class ToolNetworkTool extends AEBaseItem implements IGuiItem, IAEWrench,
 		{
 			final RayTraceResult mop = AppEng.proxy.getRTR();
 
-			if( mop == null )
+			if( mop == null || mop.typeOfHit == RayTraceResult.Type.MISS )
 			{
-				this.onItemUseFirst( p, w, new BlockPos( 0, 0, 0 ), null, 0, 0, 0, hand ); // eh?
+				NetworkHandler.instance().sendToServer( new PacketClick( BlockPos.ORIGIN, null, 0, 0, 0, hand ) );
-			}
-			else
-			{
-				if( w.getBlockState( mop.getBlockPos() ).getBlock().isAir( w.getBlockState( mop.getBlockPos() ), w, mop.getBlockPos() ) )
-				{
-					this.onItemUseFirst( p, w, new BlockPos( 0, 0, 0 ), null, 0, 0, 0, hand ); // eh?
-				}
 			}
 		}
 

src/main/java/appeng/me/NetworkEventBus.java

@@ -29,6 +29,7 @@ import java.util.Map;
 import java.util.Map.Entry;
 
 import appeng.api.networking.IGridNode;
+import appeng.api.networking.IMachineSet;
 import appeng.api.networking.events.MENetworkEvent;
 import appeng.api.networking.events.MENetworkEventSubscribe;
 import appeng.core.AELog;
@@ -114,10 +115,19 @@ public class NetworkEventBus
 						target.invoke( cache.getCache(), e );
 					}
 
-					for( final IGridNode obj : g.getMachines( subscriber.getKey() ) )
+					// events may create or remove grid nodes in rare cases
+					final IMachineSet machines = g.getMachines( subscriber.getKey() );
+					final List<IGridNode> work = new ArrayList<>( machines.size() );
+					machines.forEach( work::add );
+
+					for( final IGridNode obj : work )
 					{
-						x++;
+						// stil part of grid?
-						target.invoke( obj.getMachine(), e );
+						if( machines.contains( obj ) )
+						{
+							x++;
+							target.invoke( obj.getMachine(), e );
+						}
 					}
 				}
 			}

src/main/java/appeng/me/storage/CellInventory.java

@@ -223,7 +223,7 @@ public class CellInventory implements ICellInventory
 		// any NBT data for empty cells instead of relying on an empty IItemContainer
 		if( CellInventory.isStorageCell( input.getDefinition() ) )
 		{
-			final IMEInventory meInventory = getCell( input.getDefinition(), null );
+			final IMEInventory meInventory = getCell( input.createItemStack(), null );
 			if( meInventory != null && !this.isEmpty( meInventory ) )
 			{
 				return input;

src/main/java/appeng/tile/AEBaseTile.java

@@ -488,7 +488,7 @@ public class AEBaseTile extends TileEntity implements IOrientable, ICommonTile,
 
 	public void saveChanges()
 	{
-		super.markDirty();
+		markDirty();
 	}
 
 	public boolean requiresTESR()

src/main/java/appeng/worldgen/QuartzWorldGen.java

@@ -21,7 +21,6 @@ package appeng.worldgen;
 
 import java.util.Random;
 
-import net.minecraft.block.Block;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.World;
 import net.minecraft.world.chunk.IChunkProvider;
@@ -48,16 +47,22 @@ public final class QuartzWorldGen implements IWorldGenerator
 		final IBlockDefinition oreDefinition = blocks.quartzOre();
 		final IBlockDefinition chargedDefinition = blocks.quartzOreCharged();
 
-		final Block ore = oreDefinition.maybeBlock().orElse( null );
+		this.oreNormal = oreDefinition.maybeBlock()
-		final Block charged = chargedDefinition.maybeBlock().orElse( null );
+				.map( b -> new WorldGenMinable( b.getDefaultState(), AEConfig.instance().getQuartzOresPerCluster() ) )
-
+				.orElse( null );
-		this.oreNormal = new WorldGenMinable( ore.getDefaultState(), AEConfig.instance().getQuartzOresPerCluster() );
+		this.oreCharged = chargedDefinition.maybeBlock()
-		this.oreCharged = new WorldGenMinable( charged.getDefaultState(), AEConfig.instance().getQuartzOresPerCluster() );
+				.map( b -> new WorldGenMinable( b.getDefaultState(), AEConfig.instance().getQuartzOresPerCluster() ) )
+				.orElse( null );
 	}
 
 	@Override
 	public void generate( final Random r, final int chunkX, final int chunkZ, final World w, final IChunkGenerator chunkGenerator, final IChunkProvider chunkProvider )
 	{
+		if( this.oreNormal == null && this.oreCharged == null )
+		{
+			return;
+		}
+
 		int seaLevel = w.provider.getAverageGroundLevel() + 1;
 
 		if( seaLevel < 20 )
@@ -67,26 +72,31 @@ public final class QuartzWorldGen implements IWorldGenerator
 			seaLevel = w.getHeight( x, z );
 		}
 
-		if( this.oreNormal == null || this.oreCharged == null )
-		{
-			return;
-		}
-
 		final double oreDepthMultiplier = AEConfig.instance().getQuartzOresClusterAmount() * seaLevel / 64;
 		final int scale = (int) Math.round( r.nextGaussian() * Math.sqrt( oreDepthMultiplier ) + oreDepthMultiplier );
 
-		for( int x = 0; x < ( r.nextBoolean() ? scale * 2 : scale ) / 2; ++x )
+		for( int cnt = 0; cnt < ( r.nextBoolean() ? scale * 2 : scale ) / 2; ++cnt )
 		{
-			final boolean isCharged = r.nextFloat() > AEConfig.instance().getSpawnChargedChance();
+			boolean isCharged = false;
-			final WorldGenMinable whichOre = isCharged ? this.oreCharged : this.oreNormal;
 
-			if( WorldGenRegistry.INSTANCE.isWorldGenEnabled( isCharged ? WorldGenType.CHARGED_CERTUS_QUARTZ : WorldGenType.CERTUS_QUARTZ, w ) )
+			if( this.oreCharged != null )
 			{
-				final int cx = chunkX * 16 + r.nextInt( 22 );
+				isCharged = r.nextFloat() > AEConfig.instance().getSpawnChargedChance();
+			}
+
+			final WorldGenMinable whichOre = isCharged ? this.oreCharged : this.oreNormal;
+			if( whichOre != null && shouldGenerate( isCharged, w ) )
+			{
+				final int cx = chunkX * 16 + r.nextInt( 16 );
 				final int cy = r.nextInt( 40 * seaLevel / 64 ) + r.nextInt( 22 * seaLevel / 64 ) + 12 * seaLevel / 64;
-				final int cz = chunkZ * 16 + r.nextInt( 22 );
+				final int cz = chunkZ * 16 + r.nextInt( 16 );
 				whichOre.generate( w, r, new BlockPos( cx, cy, cz ) );
 			}
 		}
 	}
+
+	private static boolean shouldGenerate( final boolean isCharged, final World w )
+	{
+		return WorldGenRegistry.INSTANCE.isWorldGenEnabled( isCharged ? WorldGenType.CHARGED_CERTUS_QUARTZ : WorldGenType.CERTUS_QUARTZ, w );
+	}
 }