Declare batteryLevel and matterLevel as vars instead of vals

src/main/kotlin/ru/dbotthepony/mc/otm/capability/IMatteryEnergyStorage.kt

@@ -42,11 +42,25 @@ interface IMatteryEnergyStorage : IEnergyStorage {
 	 */
 	fun receiveEnergyInner(howMuch: Decimal, simulate: Boolean): Decimal
 
-	val batteryLevel: Decimal
+	var batteryLevel: Decimal
 	val maxBatteryLevel: Decimal
 	val missingPower: Decimal
 		get() = (maxBatteryLevel - batteryLevel).moreThanZero()
 
+	/**
+	 * Empties power of this energy storage
+	 */
+	fun emptyBattery() {
+		batteryLevel = Decimal.ZERO
+	}
+
+	/**
+	 * Fully fills power in this energy storage
+	 */
+	fun fillBattery() {
+		batteryLevel = maxBatteryLevel
+	}
+
 	override fun receiveEnergy(maxReceive: Int, simulate: Boolean): Int {
 		val received = receiveEnergyOuter(maxReceive, true).toInt()
 

src/main/kotlin/ru/dbotthepony/mc/otm/capability/matter/IMatterHandler.kt

@@ -8,9 +8,23 @@ import ru.dbotthepony.mc.otm.core.orNull
 import kotlin.math.roundToInt
 
 interface IMatterHandler {
-	val storedMatter: Decimal
+	var storedMatter: Decimal
 	val maxStoredMatter: Decimal
 
+	/**
+	 * Empties matter stored of this matter storage
+	 */
+	fun emptyMatter() {
+		storedMatter = Decimal.ZERO
+	}
+
+	/**
+	 * Fully fills matter stored in this matter storage
+	 */
+	fun fillMatter() {
+		storedMatter = maxStoredMatter
+	}
+
 	fun receiveMatterOuter(howMuch: Decimal, simulate: Boolean): Decimal
 	fun receiveMatterInner(howMuch: Decimal, simulate: Boolean): Decimal
 	fun extractMatterOuter(howMuch: Decimal, simulate: Boolean): Decimal

src/main/kotlin/ru/dbotthepony/mc/otm/item/BatteryItem.kt

@@ -145,20 +145,6 @@ open class BatteryItem : Item {
 		}
 	}
 
-	override fun fillItemCategory(p_41391_: CreativeModeTab, p_41392_: NonNullList<ItemStack>) {
-		super.fillItemCategory(p_41391_, p_41392_)
-
-		if (!isCreative && allowedIn(p_41391_)) {
-			p_41392_.add(ItemStack(this).also {
-				it.matteryEnergy?.let {
-					if (it is Power) {
-						it.maxPower()
-					}
-				}
-			})
-		}
-	}
-
 	override fun initCapabilities(stack: ItemStack, nbt: CompoundTag?): ICapabilityProvider {
 		return Power(stack)
 	}

src/main/kotlin/ru/dbotthepony/mc/otm/item/EnergySwordItem.kt

@@ -193,16 +193,6 @@ class EnergySwordItem : Item(Properties().stacksTo(1).rarity(Rarity.RARE)), Vani
 		return EnergyConsumerItem(stack, MAX_ENERGY)
 	}
 
-	override fun fillItemCategory(p_41391_: CreativeModeTab, p_41392_: NonNullList<ItemStack>) {
-		super.fillItemCategory(p_41391_, p_41392_)
-
-		if (allowedIn(p_41391_)) {
-			p_41392_.add(ItemStack(this).also {
-				it.matteryEnergy?.receiveEnergyInner(MAX_ENERGY, false)
-			})
-		}
-	}
-
 	override fun getAttributeModifiers(
 		slot: EquipmentSlot,
 		itemStack: ItemStack

src/main/kotlin/ru/dbotthepony/mc/otm/item/MatterCapacitorItem.kt

@@ -109,20 +109,6 @@ class MatterCapacitorItem : Item {
 		_capacity = { Decimal.LONG_MAX_VALUE }
 	}
 
-	override fun fillItemCategory(p_41391_: CreativeModeTab, p_41392_: NonNullList<ItemStack>) {
-		super.fillItemCategory(p_41391_, p_41392_)
-
-		if (!isCreative && allowedIn(p_41391_)) {
-			p_41392_.add(ItemStack(this).also {
-				it.getCapability(MatteryCapability.MATTER).ifPresentK {
-					if (it is Matter) {
-						it.storedMatter = it.maxStoredMatter
-					}
-				}
-			})
-		}
-	}
-
 	override fun isBarVisible(p_150899_: ItemStack): Boolean {
 		if (isCreative)
 			return false

src/main/kotlin/ru/dbotthepony/mc/otm/item/ProceduralExoPackSlotUpgradeItem.kt

@@ -15,7 +15,7 @@ import ru.dbotthepony.mc.otm.data.loot.IRandomizableItem
 import java.util.*
 
 @Suppress("NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS") // .tab(null) is a legal statement because tab field itself is nullable
-class ProceduralExoPackSlotUpgradeItem : AbstractExoPackSlotUpgradeItem(defaultProperties().tab(null)),
+class ProceduralExoPackSlotUpgradeItem : AbstractExoPackSlotUpgradeItem(defaultProperties()),
 	IRandomizableItem {
 	override fun getRarity(itemStack: ItemStack): Rarity {
 		return when (slotCount(itemStack)) {

src/main/kotlin/ru/dbotthepony/mc/otm/recipe/EnergyContainerRecipe.kt

@@ -17,6 +17,7 @@ import ru.dbotthepony.mc.otm.capability.ItemEnergyStorageImpl
 import ru.dbotthepony.mc.otm.capability.matteryEnergy
 import ru.dbotthepony.mc.otm.container.iterator
 import ru.dbotthepony.mc.otm.container.stream
+import ru.dbotthepony.mc.otm.core.filterNotNull
 import ru.dbotthepony.mc.otm.core.set
 import ru.dbotthepony.mc.otm.core.tagNotNull
 
@@ -37,11 +38,11 @@ class EnergyContainerRecipe(
 		val battery = container.stream()
 			.filter { !it.isEmpty }
 			.map { it.matteryEnergy }
-			.filter { it != null }
+			.filterNotNull()
 			.findAny().orElse(null)
 
 		if (battery != null) {
-			itemStack.tagNotNull[ItemEnergyStorageImpl.ENERGY_KEY] = battery.batteryLevel.serializeNBT()
+			itemStack.matteryEnergy?.batteryLevel = battery.batteryLevel
 		}
 
 		if (itemStack.isEnchantable) {

src/main/kotlin/ru/dbotthepony/mc/otm/registry/CreativeTabs.kt

@@ -3,6 +3,10 @@ package ru.dbotthepony.mc.otm.registry
 import net.minecraft.world.item.CreativeModeTab
 import net.minecraft.world.item.DyeColor
 import net.minecraft.world.item.Item
+import net.minecraft.world.item.ItemStack
+import ru.dbotthepony.mc.otm.capability.matter.matter
+import ru.dbotthepony.mc.otm.capability.matteryEnergy
+import ru.dbotthepony.mc.otm.core.registryName
 
 private fun CreativeModeTab.Output.accept(values: Collection<Item>) {
 	for (item in values) {
@@ -58,6 +62,37 @@ private fun CreativeModeTab.Output.all(values: Map<DyeColor?, Item>) {
 	colored(values)
 }
 
+private fun CreativeModeTab.Output.energized(value: Item) {
+	accept(value)
+
+	val stack = ItemStack(value, 1)
+	val energy = stack.matteryEnergy ?: throw IllegalArgumentException("${value.registryName} does not implement mattery energy capability")
+	energy.fillBattery()
+	accept(stack)
+}
+
+private fun CreativeModeTab.Output.energized(values: Iterable<Item>) {
+	for (value in values) {
+		energized(value)
+	}
+}
+
+private fun CreativeModeTab.Output.mattery(value: Item) {
+	accept(value)
+
+	val stack = ItemStack(value, 1)
+	val matter = stack.matter ?: throw IllegalArgumentException("${value.registryName} does not implement matter capability")
+
+	matter.fillMatter()
+	accept(stack)
+}
+
+private fun CreativeModeTab.Output.mattery(values: Iterable<Item>) {
+	for (value in values) {
+		mattery(value)
+	}
+}
+
 internal fun addMainCreativeTabItems(consumer: CreativeModeTab.Output) {
 	with(consumer) {
 		accept(MItems.MACHINES)
@@ -77,8 +112,8 @@ internal fun addMainCreativeTabItems(consumer: CreativeModeTab.Output) {
 		accept(MItems.TRITANIUM_TOOLS)
 		accept(MItems.TRITANIUM_ARMOR)
 
-		accept(MItems.ENERGY_SWORD)
+		energized(MItems.ENERGY_SWORD)
-		accept(MItems.PLASMA_RIFLE)
+		energized(MItems.PLASMA_RIFLE)
 
 		accept(MItems.BLACK_HOLE_SCANNER)
 		accept(MItems.GRAVITATION_FIELD_LIMITER)
@@ -87,8 +122,8 @@ internal fun addMainCreativeTabItems(consumer: CreativeModeTab.Output) {
 		accept(MItems.BLACK_HOLE)
 		accept(MItems.GRAVITATIONAL_DISRUPTOR)
 
-		accept(MItems.ALL_BATTERIES)
+		energized(MItems.ALL_BATTERIES)
-		accept(MItems.MATTER_CAPACITORS)
+		mattery(MItems.MATTER_CAPACITORS)
 
 		base(MItems.CARGO_CRATE_MINECARTS)