1 files changed, 75 insertions, 0 deletions
diff --git a/src/main/kotlin/features/debug/itemeditor/LegacyItemData.kt b/src/main/kotlin/features/debug/itemeditor/LegacyItemData.kt
new file mode 100644
index 0000000..c0f48ca
--- /dev/null
+++ b/src/main/kotlin/features/debug/itemeditor/LegacyItemData.kt
@@ -0,0 +1,75 @@
+package moe.nea.firmament.features.debug.itemeditor
+
+import kotlinx.serialization.Serializable
+import kotlin.jvm.optionals.getOrNull
+import net.minecraft.item.ItemStack
+import net.minecraft.nbt.NbtCompound
+import net.minecraft.util.Identifier
+import moe.nea.firmament.Firmament
+import moe.nea.firmament.repo.ExpensiveItemCacheApi
+import moe.nea.firmament.repo.ItemCache
+import moe.nea.firmament.util.MC
+
+/**
+ * Load data based on [prismarine.js' 1.8 item data](https://github.com/PrismarineJS/minecraft-data/blob/master/data/pc/1.8/items.json)
+ */
+object LegacyItemData {
+	@Serializable
+	data class ItemData(
+		val id: Int,
+		val name: String,
+		val displayName: String,
+		val stackSize: Int,
+		val variations: List<Variation> = listOf()
+	) {
+		val properId = if (name.contains(":")) name else "minecraft:$name"
+
+		fun allVariants() =
+			variations.map { LegacyItemType(properId, it.metadata.toShort()) } + LegacyItemType(properId, 0)
+	}
+
+	@Serializable
+	data class Variation(
+		val metadata: Int, val displayName: String
+	)
+
+	data class LegacyItemType(
+		val name: String,
+		val metadata: Short
+	) {
+		override fun toString(): String {
+			return "$name:$metadata"
+		}
+	}
+
+	@Serializable
+	data class EnchantmentData(
+		val id: Int,
+		val name: String,
+		val displayName: String,
+	)
+
+	inline fun <reified T : Any> getLegacyData(name: String) =
+		Firmament.tryDecodeJsonFromStream<T>(
+			LegacyItemData::class.java.getResourceAsStream("/legacy_data/$name.json")!!
+		).getOrThrow()
+
+	val enchantmentData = getLegacyData<List<EnchantmentData>>("enchantments")
+	val enchantmentLut = enchantmentData.associateBy { Identifier.ofVanilla(it.name) }
+
+	val itemDat = getLegacyData<List<ItemData>>("items")
+	@OptIn(ExpensiveItemCacheApi::class) // This is fine, we get loaded in a thread.
+	val itemLut = itemDat.flatMap { item ->
+		item.allVariants().map { legacyItemType ->
+			val nbt = ItemCache.convert189ToModern(NbtCompound().apply {
+				putString("id", legacyItemType.name)
+				putByte("Count", 1)
+				putShort("Damage", legacyItemType.metadata)
+			})!!
+			val stack = ItemStack.fromNbt(MC.defaultRegistries, nbt).getOrNull()
+				?: error("Could not transform ${legacyItemType}")
+			stack.item to legacyItemType
+		}
+	}.toMap()
+
+}