Replace references to NEU with Firmament

src/main/kotlin/moe/nea/firmament/util/SkyblockId.kt

@@ -0,0 +1,48 @@
+package moe.nea.firmament.util
+
+import io.github.moulberry.repo.data.NEUItem
+import io.github.moulberry.repo.data.Rarity
+import kotlinx.serialization.Serializable
+import kotlinx.serialization.decodeFromString
+import kotlinx.serialization.json.Json
+import net.minecraft.item.ItemStack
+import net.minecraft.nbt.NbtCompound
+import net.minecraft.util.Identifier
+
+@JvmInline
+value class SkyblockId(val neuItem: String) {
+    val identifier get() = Identifier("skyblockitem", neuItem.lowercase().replace(";", "__"))
+}
+
+val NEUItem.skyblockId get() = SkyblockId(skyblockItemId)
+
+@Serializable
+data class HypixelPetInfo(
+    val type: String,
+    val tier: Rarity,
+) {
+    val skyblockId get() = SkyblockId("${type.uppercase()};${tier.ordinal}")
+}
+
+private val jsonparser = Json { ignoreUnknownKeys = true }
+
+val ItemStack.extraAttributes: NbtCompound
+    get() = getOrCreateSubNbt("ExtraAttributes")
+
+val ItemStack.skyBlockId: SkyblockId?
+    get() {
+        when (val id = extraAttributes.getString("id")) {
+            "PET" -> {
+                val jsonString = extraAttributes.getString("petInfo")
+                if (jsonString.isNullOrBlank()) return null
+                val petInfo =
+                    runCatching { jsonparser.decodeFromString<HypixelPetInfo>(jsonString) }
+                        .getOrElse { return null }
+                return petInfo.skyblockId
+            }
+            // TODO: RUNE, ENCHANTED_BOOK, PARTY_HAT_CRAB{,_ANIMATED}, ABICASE
+            else -> {
+                return SkyblockId(id)
+            }
+        }
+    }