PhysicalConnectivity/src/main/kotlin/net/shadowfacts/phycon/networking/C2STerminalRequestItem.kt

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.item.ItemStack
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.minecraft.util.registry.Registry
import net.minecraft.util.registry.RegistryKey
import net.shadowfacts.phycon.PhysicalConnectivity
import net.shadowfacts.phycon.block.terminal.AbstractTerminalBlockEntity
import net.shadowfacts.phycon.util.readItemStackWithoutCount
import net.shadowfacts.phycon.util.writeItemStackWithoutCount

/**
 * @author shadowfacts
 */
object C2STerminalRequestItem: ServerReceiver {

	override val CHANNEL = Identifier(PhysicalConnectivity.MODID, "terminal_request_item")

	operator fun invoke(terminal: AbstractTerminalBlockEntity, stack: ItemStack, amount: Int): Packet<*> {
		val buf = PacketByteBufs.create()
		buf.writeIdentifier(terminal.world!!.registryKey.value)
		buf.writeBlockPos(terminal.pos)

		// Don't send the count of the fake stack when sending over the network because
		// PacketByteBuf serializes the stack count as a byte. Otherwise counts > 127 will result in
		// an overflow and be negative on the receiving side.
		buf.writeItemStackWithoutCount(stack)

		buf.writeVarInt(amount)
		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 stack = buf.readItemStackWithoutCount()
		val amount = buf.readVarInt()

		server.execute {
			val key = RegistryKey.of(Registry.WORLD_KEY, dimID)
			val world = server.getWorld(key) ?: return@execute
			val terminal = world.getBlockEntity(pos) as? AbstractTerminalBlockEntity ?: return@execute
			terminal.requestItem(stack, amount)
		}
	}

}