Calculate terminal displayed items on the server

Avoids sending giant S2C packets containing all items in the network
when the network contains a great variety of different items

src/main/kotlin/net/shadowfacts/phycon/PhysicalConnectivity.kt

@@ -7,6 +7,7 @@ import net.shadowfacts.phycon.init.PhyBlocks
 import net.shadowfacts.phycon.init.PhyItems
 import net.shadowfacts.phycon.init.PhyScreens
 import net.shadowfacts.phycon.networking.C2STerminalRequestItem
+import net.shadowfacts.phycon.networking.C2STerminalUpdateDisplayedItems
 import net.shadowfacts.phycon.networking.ServerReceiver
 
 /**
@@ -23,6 +24,7 @@ object PhysicalConnectivity: ModInitializer {
 		PhyScreens.init()
 
 		registerGlobalReceiver(C2STerminalRequestItem)
+		registerGlobalReceiver(C2STerminalUpdateDisplayedItems)
 	}
 
 	private fun registerGlobalReceiver(receiver: ServerReceiver) {

src/main/kotlin/net/shadowfacts/phycon/PhysicalConnectivityClient.kt

@@ -2,19 +2,30 @@ package net.shadowfacts.phycon
 
 import net.fabricmc.api.ClientModInitializer
 import net.fabricmc.fabric.api.blockrenderlayer.v1.BlockRenderLayerMap
+import net.fabricmc.fabric.api.client.networking.v1.ClientPlayNetworking
 import net.fabricmc.fabric.api.client.screenhandler.v1.ScreenRegistry
 import net.minecraft.client.render.RenderLayer
 import net.shadowfacts.phycon.init.PhyBlocks
 import net.shadowfacts.phycon.init.PhyScreens
 import net.shadowfacts.phycon.network.block.terminal.TerminalScreen
+import net.shadowfacts.phycon.networking.ClientReceiver
+import net.shadowfacts.phycon.networking.S2CTerminalUpdateDisplayedItems
 
 /**
  * @author shadowfacts
  */
 object PhysicalConnectivityClient: ClientModInitializer {
+
 	override fun onInitializeClient() {
 		BlockRenderLayerMap.INSTANCE.putBlock(PhyBlocks.CABLE, RenderLayer.getTranslucent())
 
 		ScreenRegistry.register(PhyScreens.TERMINAL_SCREEN_HANDLER, ::TerminalScreen)
+
+		registerGlobalReceiver(S2CTerminalUpdateDisplayedItems)
 	}
+
+	private fun registerGlobalReceiver(receiver: ClientReceiver) {
+		ClientPlayNetworking.registerGlobalReceiver(receiver.CHANNEL, receiver)
+	}
+
 }

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

@@ -56,7 +56,7 @@ class TerminalBlockEntity: DeviceBlockEntity(PhyBlockEntities.TERMINAL),
 
 	private var observers = 0
 	val cachedNetItems = ItemStackCollections.intMap()
-	var cachedSortedNetItems = listOf<ItemStack>()
+//	var cachedSortedNetItems = listOf<ItemStack>()
 
 	var netItemObserver: WeakReference<NetItemObserver>? = null
 
@@ -86,14 +86,12 @@ class TerminalBlockEntity: DeviceBlockEntity(PhyBlockEntities.TERMINAL),
 
 	private fun handleReadInventory(packet: ReadInventoryPacket) {
 		inventoryCache[packet.source] = packet.inventory
-		updateNetItems()
+		updateAndSync()
-		sync()
 	}
 
 	private fun handleDeviceRemoved(packet: DeviceRemovedPacket) {
 		inventoryCache.remove(packet.source)
-		updateNetItems()
+		updateAndSync()
-		sync()
 	}
 
 	private fun handleStackLocation(packet: StackLocationPacket) {
@@ -113,12 +111,17 @@ class TerminalBlockEntity: DeviceBlockEntity(PhyBlockEntities.TERMINAL),
 
 		// this happens outside the normal update loop because by receiving the item stack packet
 		// we "know" how much the count in the source inventory has changed
-		updateNetItems()
+		updateAndSync()
-		sync()
 
 		return remaining
 	}
 
+	private fun updateAndSync() {
+		updateNetItems()
+		sync()
+		netItemObserver?.get()?.netItemsChanged()
+	}
+
 	private fun updateNetItems() {
 		cachedNetItems.clear()
 		for (inventory in inventoryCache.values) {
@@ -127,12 +130,12 @@ class TerminalBlockEntity: DeviceBlockEntity(PhyBlockEntities.TERMINAL),
 				cachedNetItems.mergeInt(stack, amount) { a, b -> a + b }
 			}
 		}
-		// todo: is the map necessary or is just the sorted list enough?
+//		// todo: is the map necessary or is just the sorted list enough?
-		cachedSortedNetItems = cachedNetItems.object2IntEntrySet().sortedByDescending { it.intValue }.map {
+//		cachedSortedNetItems = cachedNetItems.object2IntEntrySet().sortedByDescending { it.intValue }.map {
-			val stack = it.key.copy()
+//			val stack = it.key.copy()
-			stack.count = it.intValue
+//			stack.count = it.intValue
-			stack
+//			stack
-		}
+//		}
 	}
 
 	private fun beginInsertions() {
@@ -175,21 +178,15 @@ class TerminalBlockEntity: DeviceBlockEntity(PhyBlockEntities.TERMINAL),
 				finishTimedOutPendingInsertions()
 			}
 
-			if (observers > 0) {
+			if (observers > 0 && !world!!.isClient) {
-				if (world!!.isClient) {
+				updateAndSync()
-					println(cachedNetItems)
-				} else {
-					updateNetItems()
-					sync()
-				}
 			}
 		}
 	}
 
 	fun onActivate(player: PlayerEntity) {
 		if (!world!!.isClient) {
-			updateNetItems()
+			updateAndSync()
-			sync()
 
 			inventoryCache.clear()
 			sendPacket(RequestInventoryPacket(ipAddress))
@@ -238,8 +235,7 @@ class TerminalBlockEntity: DeviceBlockEntity(PhyBlockEntities.TERMINAL),
 		internalBuffer.setStack(insertion.bufferSlot, remaining)
 
 		// as with extracting, we "know" the new amounts and so can update instantly without actually sending out packets
-		updateNetItems()
+		updateAndSync()
-		sync()
 
 		return remaining
 	}
@@ -263,31 +259,31 @@ class TerminalBlockEntity: DeviceBlockEntity(PhyBlockEntities.TERMINAL),
 
 	override fun toClientTag(tag: CompoundTag): CompoundTag {
 		tag.put("InternalBuffer", internalBuffer.toTag())
-		val list = ListTag()
+//		val list = ListTag()
-		tag.put("CachedNetItems", list)
+//		tag.put("CachedNetItems", list)
-		for ((stack, amount) in cachedNetItems) {
+//		for ((stack, amount) in cachedNetItems) {
-			val entryTag = stack.toTag(CompoundTag())
+//			val entryTag = stack.toTag(CompoundTag())
-			entryTag.putInt("NetAmount", amount)
+//			entryTag.putInt("NetAmount", amount)
-			list.add(entryTag)
+//			list.add(entryTag)
-		}
+//		}
 		return tag
 	}
 
 	override fun fromClientTag(tag: CompoundTag) {
 		internalBuffer.fromTag(tag.getCompound("InternalBuffer"))
-		val list = tag.getList("CachedNetItems", 10)
+//		val list = tag.getList("CachedNetItems", 10)
-		cachedNetItems.clear()
+//		cachedNetItems.clear()
-		for (entryTag in list) {
+//		for (entryTag in list) {
-			val stack = ItemStack.fromTag(entryTag as CompoundTag)
+//			val stack = ItemStack.fromTag(entryTag as CompoundTag)
-			val netAmount = entryTag.getInt("NetAmount")
+//			val netAmount = entryTag.getInt("NetAmount")
-			cachedNetItems[stack] = netAmount
+//			cachedNetItems[stack] = netAmount
-		}
+//		}
-		netItemObserver?.get()?.netItemsChanged()
+//		netItemObserver?.get()?.netItemsChanged()
-		cachedSortedNetItems = cachedNetItems.object2IntEntrySet().sortedByDescending { it.intValue }.map {
+//		cachedSortedNetItems = cachedNetItems.object2IntEntrySet().sortedByDescending { it.intValue }.map {
-			val stack = it.key.copy()
+//			val stack = it.key.copy()
-			stack.count = it.intValue
+//			stack.count = it.intValue
-			stack
+//			stack
-		}
+//		}
 	}
 
 	interface NetItemObserver {

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

@@ -17,6 +17,7 @@ import net.minecraft.text.LiteralText
 import net.minecraft.text.Text
 import net.minecraft.util.Identifier
 import net.shadowfacts.phycon.PhysicalConnectivity
+import net.shadowfacts.phycon.networking.C2STerminalUpdateDisplayedItems
 import net.shadowfacts.phycon.util.SortMode
 import org.lwjgl.glfw.GLFW
 import java.lang.NumberFormatException
@@ -34,6 +35,7 @@ class TerminalScreen(handler: TerminalScreenHandler, playerInv: PlayerInventory,
 	}
 
 	private lateinit var searchBox: TextFieldWidget
+	private lateinit var sortButton: SortButton
 	private lateinit var amountBox: TextFieldWidget
 	private var dialogStack = ItemStack.EMPTY
 	private var showingAmountDialog = false
@@ -77,9 +79,8 @@ class TerminalScreen(handler: TerminalScreenHandler, playerInv: PlayerInventory,
 		searchBox.setEditableColor(0xffffff)
 		addChild(searchBox)
 
-		val sortButton = SortButton(x + 256, y + 0, handler.sortMode, {
+		sortButton = SortButton(x + 256, y + 0, handler.sortMode, {
-			handler.sortMode = it
+			requestUpdatedItems()
-			handler.netItemsChanged()
 		}, ::renderTooltip)
 		addButton(sortButton)
 
@@ -138,6 +139,13 @@ class TerminalScreen(handler: TerminalScreenHandler, playerInv: PlayerInventory,
 			doDialogRequest()
 		}
 		dialogChildren.add(request)
+
+		requestUpdatedItems()
+	}
+
+	private fun requestUpdatedItems() {
+		val player = MinecraftClient.getInstance().player!!
+		player.networkHandler.sendPacket(C2STerminalUpdateDisplayedItems(handler.terminal, searchBox.text, sortButton.mode))
 	}
 
 	override fun tick() {
@@ -279,7 +287,7 @@ class TerminalScreen(handler: TerminalScreenHandler, playerInv: PlayerInventory,
 			val oldText = searchBox.text
 			if (searchBox.charTyped(c, i)) {
 				if (searchBox.text != oldText) {
-					search()
+					requestUpdatedItems()
 				}
 				return true
 			}
@@ -307,7 +315,7 @@ class TerminalScreen(handler: TerminalScreenHandler, playerInv: PlayerInventory,
 			val oldText = searchBox.text
 			if (searchBox.keyPressed(key, j, k)) {
 				if (searchBox.text != oldText) {
-					search()
+					requestUpdatedItems()
 				}
 				return true
 			}
@@ -319,10 +327,6 @@ class TerminalScreen(handler: TerminalScreenHandler, playerInv: PlayerInventory,
 		}
 	}
 
-	private fun search() {
-		screenHandler.search(searchBox.text)
-	}
-
 	private fun doDialogRequest() {
 		showingAmountDialog = false
 		handler.requestItem(client!!.player!!, dialogStack, amountBox.intValue)

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

@@ -8,12 +8,14 @@ import net.minecraft.entity.player.PlayerInventory
 import net.minecraft.item.ItemStack
 import net.minecraft.network.PacketByteBuf
 import net.minecraft.screen.ScreenHandler
+import net.minecraft.server.network.ServerPlayerEntity
 import net.minecraft.util.Identifier
 import net.minecraft.util.registry.Registry
 import net.shadowfacts.phycon.PhysicalConnectivity
 import net.shadowfacts.phycon.init.PhyBlocks
 import net.shadowfacts.phycon.init.PhyScreens
 import net.shadowfacts.phycon.networking.C2STerminalRequestItem
+import net.shadowfacts.phycon.networking.S2CTerminalUpdateDisplayedItems
 import net.shadowfacts.phycon.util.SortMode
 import java.lang.ref.WeakReference
 import kotlin.math.ceil
@@ -22,7 +24,7 @@ import kotlin.math.min
 /**
  * @author shadowfacts
  */
-class TerminalScreenHandler(syncId: Int, playerInv: PlayerInventory, val terminal: TerminalBlockEntity): ScreenHandler(PhyScreens.TERMINAL_SCREEN_HANDLER, syncId),
+class TerminalScreenHandler(syncId: Int, val playerInv: PlayerInventory, val terminal: TerminalBlockEntity): ScreenHandler(PhyScreens.TERMINAL_SCREEN_HANDLER, syncId),
 	TerminalBlockEntity.NetItemObserver {
 
 	companion object {
@@ -32,6 +34,18 @@ class TerminalScreenHandler(syncId: Int, playerInv: PlayerInventory, val termina
 	private val fakeInv = FakeInventory(this)
 	private var searchQuery: String = ""
 	var sortMode = SortMode.COUNT_HIGH_FIRST
+		private set
+	private var itemEntries = listOf<Entry>()
+		set(value) {
+			field = value
+			if (terminal.world!!.isClient) {
+				itemsForDisplay = value.map {
+					val stack = it.stack.copy()
+					stack.count = it.amount
+					stack
+				}
+			}
+		}
 	var itemsForDisplay = listOf<ItemStack>()
 		private set
 
@@ -39,8 +53,10 @@ class TerminalScreenHandler(syncId: Int, playerInv: PlayerInventory, val termina
 			this(syncId, playerInv, PhyBlocks.TERMINAL.getBlockEntity(playerInv.player.world, buf.readBlockPos())!!)
 
 	init {
-		terminal.netItemObserver = WeakReference(this)
+		if (!terminal.world!!.isClient) {
-		netItemsChanged()
+			terminal.netItemObserver = WeakReference(this)
+			netItemsChanged()
+		}
 
 		// network
 		for (y in 0 until 6) {
@@ -69,6 +85,9 @@ class TerminalScreenHandler(syncId: Int, playerInv: PlayerInventory, val termina
 	}
 
 	override fun netItemsChanged() {
+		val player = playerInv.player
+		assert(player is ServerPlayerEntity)
+
 		val filtered = terminal.cachedNetItems.object2IntEntrySet().filter {
 			if (searchQuery.isBlank()) return@filter true
 			if (searchQuery.startsWith('@')) {
@@ -88,18 +107,25 @@ class TerminalScreenHandler(syncId: Int, playerInv: PlayerInventory, val termina
 				SortMode.ALPHABETICAL -> filtered.sortedBy { it.key.name.string }
 			}
 
-		itemsForDisplay = sorted.map {
+		itemEntries = sorted.map { Entry(it.key, it.intValue) }
-			val stack = it.key.copy()
+
-			stack.count = it.intValue
+		(player as ServerPlayerEntity).networkHandler.sendPacket(S2CTerminalUpdateDisplayedItems(terminal, itemEntries, searchQuery, sortMode))
-			stack
-		}
 	}
 
-	fun search(query: String) {
+	fun sendUpdatedItemsToClient(player: ServerPlayerEntity, query: String, sortMode: SortMode) {
-		searchQuery = query
+		this.searchQuery = query
+		this.sortMode = sortMode
 		netItemsChanged()
 	}
 
+	fun receivedUpdatedItemsFromServer(entries: List<Entry>, query: String, sortMode: SortMode) {
+		assert(playerInv.player.world.isClient)
+
+		this.searchQuery = query
+		this.sortMode = sortMode
+		itemEntries = entries
+	}
+
 	override fun canUse(player: PlayerEntity): Boolean {
 		return true
 	}
@@ -214,4 +240,6 @@ class TerminalScreenHandler(syncId: Int, playerInv: PlayerInventory, val termina
 	fun isNetworkSlot(id: Int) = id in 0 until bufferSlotsStart
 	fun isBufferSlot(id: Int) = id in bufferSlotsStart until playerSlotsStart
 	fun isPlayerSlot(id: Int) = id >= playerSlotsStart
+
+	data class Entry(val stack: ItemStack, val amount: Int)
 }

src/main/kotlin/net/shadowfacts/phycon/networking/C2STerminalUpdateDisplayedItems.kt

@@ -0,0 +1,50 @@
+package net.shadowfacts.phycon.networking
+
+import net.fabricmc.fabric.api.client.networking.v1.ClientPlayNetworking
+import net.fabricmc.fabric.api.networking.v1.PacketByteBufs
+import net.fabricmc.fabric.api.networking.v1.PacketSender
+import net.minecraft.network.Packet
+import net.minecraft.network.PacketByteBuf
+import net.minecraft.server.MinecraftServer
+import net.minecraft.server.network.ServerPlayNetworkHandler
+import net.minecraft.server.network.ServerPlayerEntity
+import net.minecraft.util.Identifier
+import net.shadowfacts.phycon.PhysicalConnectivity
+import net.shadowfacts.phycon.network.block.terminal.TerminalBlockEntity
+import net.shadowfacts.phycon.network.block.terminal.TerminalScreenHandler
+import net.shadowfacts.phycon.util.SortMode
+
+/**
+ * @author shadowfacts
+ */
+object C2STerminalUpdateDisplayedItems: ServerReceiver {
+
+	override val CHANNEL = Identifier(PhysicalConnectivity.MODID, "terminal_update_displayed")
+
+	operator fun invoke(terminal: TerminalBlockEntity, query: String, sortMode: SortMode): Packet<*> {
+		val buf = PacketByteBufs.create()
+
+		buf.writeIdentifier(terminal.world!!.registryKey.value)
+		buf.writeBlockPos(terminal.pos)
+
+		buf.writeString(query)
+		buf.writeVarInt(sortMode.ordinal)
+
+		return ClientPlayNetworking.createC2SPacket(CHANNEL, buf)
+	}
+
+	override fun receive(server: MinecraftServer, player: ServerPlayerEntity, handler: ServerPlayNetworkHandler, buf: PacketByteBuf, responseSender: PacketSender) {
+		val dimID = buf.readIdentifier()
+		val pos = buf.readBlockPos()
+		val query = buf.readString()
+		val sortMode = SortMode.values()[buf.readVarInt()]
+
+		server.execute {
+			if (player.world.registryKey.value != dimID) return@execute
+			val screenHandler = player.currentScreenHandler
+			if (screenHandler !is TerminalScreenHandler) return@execute
+			if (screenHandler.terminal.pos != pos) return@execute
+			screenHandler.sendUpdatedItemsToClient(player, query, sortMode)
+		}
+	}
+}

src/main/kotlin/net/shadowfacts/phycon/networking/ClientReceiver.kt

@@ -0,0 +1,11 @@
+package net.shadowfacts.phycon.networking
+
+import net.fabricmc.fabric.api.client.networking.v1.ClientPlayNetworking
+import net.minecraft.util.Identifier
+
+/**
+ * @author shadowfacts
+ */
+interface ClientReceiver: ClientPlayNetworking.PlayChannelHandler {
+	val CHANNEL: Identifier
+}

src/main/kotlin/net/shadowfacts/phycon/networking/S2CTerminalUpdateDisplayedItems.kt

@@ -0,0 +1,57 @@
+package net.shadowfacts.phycon.networking
+
+import net.fabricmc.fabric.api.networking.v1.PacketByteBufs
+import net.fabricmc.fabric.api.networking.v1.PacketSender
+import net.fabricmc.fabric.api.networking.v1.ServerPlayNetworking
+import net.minecraft.client.MinecraftClient
+import net.minecraft.client.network.ClientPlayNetworkHandler
+import net.minecraft.network.Packet
+import net.minecraft.network.PacketByteBuf
+import net.shadowfacts.phycon.network.block.terminal.TerminalBlockEntity
+import net.shadowfacts.phycon.network.block.terminal.TerminalScreenHandler
+import net.shadowfacts.phycon.util.SortMode
+
+/**
+ * @author shadowfacts
+ */
+object S2CTerminalUpdateDisplayedItems: ClientReceiver {
+	override val CHANNEL = C2STerminalUpdateDisplayedItems.CHANNEL
+
+	operator fun invoke(terminal: TerminalBlockEntity, entries: List<TerminalScreenHandler.Entry>, query: String, sortMode: SortMode): Packet<*> {
+		val buf = PacketByteBufs.create()
+
+		buf.writeIdentifier(terminal.world!!.registryKey.value)
+		buf.writeBlockPos(terminal.pos)
+
+		buf.writeVarInt(entries.size)
+		for (e in entries) {
+			buf.writeItemStack(e.stack)
+			buf.writeVarInt(e.amount)
+		}
+
+		buf.writeString(query)
+		buf.writeVarInt(sortMode.ordinal)
+
+		return ServerPlayNetworking.createS2CPacket(CHANNEL, buf)
+	}
+
+	override fun receive(client: MinecraftClient, handler: ClientPlayNetworkHandler, buf: PacketByteBuf, responseSender: PacketSender) {
+		val dimID = buf.readIdentifier()
+		val pos = buf.readBlockPos()
+		val entryCount = buf.readVarInt()
+		val entries = ArrayList<TerminalScreenHandler.Entry>(entryCount)
+		for (i in 0 until entryCount) {
+			entries.add(TerminalScreenHandler.Entry(buf.readItemStack(), buf.readVarInt()))
+		}
+		val query = buf.readString()
+		val sortMode = SortMode.values()[buf.readVarInt()]
+
+		client.execute {
+			if (client.player!!.world.registryKey.value != dimID) return@execute
+			val screenHandler = client.player!!.currentScreenHandler
+			if (screenHandler !is TerminalScreenHandler) return@execute
+			if (screenHandler.terminal.pos != pos) return@execute
+			screenHandler.receivedUpdatedItemsFromServer(entries, query, sortMode)
+		}
+	}
+}

src/main/kotlin/net/shadowfacts/phycon/util/SortMode.kt

@@ -12,7 +12,7 @@ enum class SortMode {
 	ALPHABETICAL;
 
 	val prev: SortMode
-		get() = values()[(ordinal - 1) % values().size]
+		get() = values()[(ordinal - 1 + values().size) % values().size]
 
 	val next: SortMode
 		get() = values()[(ordinal + 1) % values().size]