package net.shadowfacts.phycon.block.terminal

import alexiil.mc.lib.attributes.item.ItemStackUtil
import net.minecraft.inventory.SimpleInventory
import net.minecraft.item.ItemStack
import net.minecraft.nbt.NbtCompound
import net.minecraft.nbt.NbtIntArray
import net.shadowfacts.phycon.util.fromTag
import net.shadowfacts.phycon.util.toTag
import kotlin.math.min

/**
 * @author shadowfacts
 */
class TerminalBufferInventory(size: Int): SimpleInventory(size) {

	enum class Mode {
		TO_NETWORK, FROM_NETWORK, UNASSIGNED
	}

	var modes = Array(size) { Mode.UNASSIGNED }
		private set

	fun toTag(): NbtCompound {
		val compound = NbtCompound()
		compound.put("Inventory", (this as SimpleInventory).toTag())
		compound.put("Modes", NbtIntArray(modes.map(Mode::ordinal)))
		return compound
	}

	fun fromTag(tag: NbtCompound) {
		val inventory = tag.getList("Inventory", 10)
		(this as SimpleInventory).fromTag(inventory)
		tag.getIntArray("Modes").forEachIndexed { i, it -> modes[i] = Mode.values()[it] }
	}

	fun insert(stack: ItemStack, mode: Mode): ItemStack {
		var remaining = stack.copy()
		for (slot in 0 until size()) {
			if (modes[slot] != mode && modes[slot] != Mode.UNASSIGNED) continue

			remaining = tryInsert(stack, slot, mode)

			if (remaining.isEmpty) {
				break
			}
		}
		return remaining
	}

	private fun tryInsert(stack: ItemStack, slot: Int, mode: Mode): ItemStack {
		val current = getStack(slot)
		if (current.isEmpty) {
			setStack(slot, stack)
			markSlot(slot, mode)
			return ItemStack.EMPTY
		} else if (ItemStackUtil.areEqualIgnoreAmounts(stack, current)) {
			val toTransfer = min(current.maxCount - current.count, stack.count)
			current.count += toTransfer
			stack.count -= toTransfer
			markSlot(slot, mode)
			return stack
		} else {
			return stack
		}
	}

	override fun setStack(slot: Int, stack: ItemStack) {
		if (stack.isEmpty) {
			modes[slot] = Mode.UNASSIGNED
		}
		super.setStack(slot, stack)
	}

	override fun clear() {
		super.clear()
		this.modes = Array(size()) { Mode.UNASSIGNED }
	}

	fun getMode(slot: Int): Mode {
		return modes[slot]
	}

	fun markSlot(slot: Int, mode: Mode) {
		modes[slot] = mode
	}

}