Explicitly specify packet destinations instead of broadcasting to all

connected sinks

src/main/kotlin/net/shadowfacts/phycon/network/DeviceBlockEntity.kt

@@ -7,6 +7,7 @@ import net.minecraft.util.Tickable
 import net.shadowfacts.phycon.api.PacketSink
 import net.shadowfacts.phycon.api.packet.Packet
 import net.shadowfacts.phycon.api.util.MACAddress
+import java.lang.ref.WeakReference
 import java.util.*
 
 /**
@@ -17,7 +18,7 @@ abstract class DeviceBlockEntity(type: BlockEntityType<*>): BlockEntity(type), T
 	var macAddress = MACAddress.random()
 		protected set
 
-	private val sendQueue = LinkedList<Packet>()
+	private val sendQueue = LinkedList<Pair<Packet, WeakReference<PacketSink>>>()
 
 	override fun handle(packet: Packet) {
 		if (acceptsPacket(packet)) {
@@ -35,21 +36,33 @@ abstract class DeviceBlockEntity(type: BlockEntityType<*>): BlockEntity(type), T
 		}
 	}
 
-	fun acceptsMulticastPacket(packet: Packet): Boolean {
+	open fun acceptsMulticastPacket(packet: Packet): Boolean {
 		return false
 	}
 
-	fun enqueue(packet: Packet) {
-		sendQueue.add(packet)
+	fun enqueue(packet: Packet, destination: PacketSink) {
+		sendQueue.add(packet to WeakReference(destination))
+	}
+
+	// todo: better name for this
+	fun enqueueToSingle(packet: Packet) {
+		val destinations = NetworkUtil.findDestinations(world!!, pos)
+		if (destinations.size != 1) {
+			// todo: handle this better
+			println("Can't send packet, multiple destinations available: $destinations")
+			return
+		}
+		enqueue(packet, destinations.first())
+	}
+
+	fun enqueueToAll(packet: Packet) {
+		sendQueue.addAll(NetworkUtil.findDestinations(world!!, pos).map { packet to WeakReference(it) })
 	}
 
 	override fun tick() {
 		if (sendQueue.isNotEmpty()) {
-			val packet = sendQueue.pop()
-			val destinations = NetworkUtil.findDestinations(world!!, pos)
-			destinations.forEach {
-				it.handle(packet)
-			}
+			val (packet, destination) = sendQueue.pop()
+			destination.get()?.handle(packet)
 		}
 	}
 

src/main/kotlin/net/shadowfacts/phycon/network/block/networkinterface/NetworkInterfaceBlockEntity.kt

@@ -43,7 +43,7 @@ class NetworkInterfaceBlockEntity: DeviceBlockEntity(PhyBlockEntities.NETWORK_IN
 	}
 
 	fun handleReadAll(packet: RequestReadAllPacket) {
-		enqueue(ReadAllPacket(readAll(), macAddress, packet.source))
+		enqueueToSingle(ReadAllPacket(readAll(), macAddress, packet.source))
 	}
 
 	fun readAll(): Map<ItemStack, Int> {

src/main/kotlin/net/shadowfacts/phycon/network/block/terminal/TerminalBlockEntity.kt

@@ -31,7 +31,7 @@ class TerminalBlockEntity: DeviceBlockEntity(PhyBlockEntities.TERMINAL) {
 	fun onActivate() {
 		if (!world!!.isClient) {
 			cachedItems.clear()
-			enqueue(RequestReadAllPacket(macAddress))
+			enqueueToSingle(RequestReadAllPacket(macAddress))
 		}
 	}