look at the code if you want to know what i did

level/litematic/main.go

@@ -0,0 +1,71 @@
+package main
+
+import (
+	"github.com/admin-else/strom/data"
+	"github.com/go-viper/mapstructure/v2"
+)
+
+type Position struct {
+	X, Y, Z int32
+}
+
+type MetaData struct {
+	Author        string
+	Description   string
+	Name          string
+	TimeCreated   int64
+	TimeModified  int64
+	TotalBlocks   int32
+	TotalVolume   int32
+	RegionCount   int32
+	EnclosingSize Position
+}
+
+type BlockState struct {
+	Name       string
+	Properties map[string]string
+}
+
+type Region struct {
+	Position          Position
+	Size              Position
+	BlockStatePalette []BlockState
+	BlockStates       []int64
+}
+
+type File struct {
+	Version              int32
+	SubVersion           int32
+	MinecraftDataVersion int32
+	Metadata             MetaData
+	Regions              map[string]Region
+}
+
+type Structure struct {
+	File
+	BlockStatePalletRealized map[string][]int32
+}
+
+func Load(v any) (s *Structure, err error) {
+	s = &Structure{}
+	err = mapstructure.Decode(v, &s.File)
+	if err != nil {
+		return
+	}
+	ret, err := data.LookUpVersionByDataVersion(s.MinecraftDataVersion)
+	if err != nil {
+		return
+	}
+	for k, r := range s.Regions {
+		s.BlockStatePalletRealized[k] = make([]int32, len(r.BlockStatePalette))
+		for i, b := range r.BlockStatePalette {
+			var stateId int32
+			stateId, err = data.StateIdFromBlocKAndStateMap(ret.MinecraftVersion, b.Name, b.Properties)
+			if err != nil {
+				return
+			}
+			s.BlockStatePalletRealized[k][i] = stateId
+		}
+	}
+	return
+}