From d0844dd6b584f3c81e1666b0434c6a1ef69669e2 Mon Sep 17 00:00:00 2001
From: adman <adman.else@gmail.com>
Date: Sat, 2 May 2026 01:36:29 +0200
Subject: [PATCH] anvil chunk to real chunk conversion things

---
 data/blocks.go       |  7 ++++-
 level/anvil/chunk.go | 62 +++++++++++++++++++++++++++++++++++++++++---
 level/storage.go     |  9 +++++++
 3 files changed, 74 insertions(+), 4 deletions(-)

diff --git a/data/blocks.go b/data/blocks.go
index f3bae8a..9597df1 100644
--- a/data/blocks.go
+++ b/data/blocks.go
@@ -99,7 +99,12 @@ func StateIdFromBlocKAndStateMap(version string, name string, stateMap map[strin
 		err = BlockNotFoundErr
 		return
 	}
-	stateId, err = b.IdFromStateMap(stateMap)
+	if stateMap == nil {
+		stateId = b.DefaultState
+	} else {
+		stateId, err = b.IdFromStateMap(stateMap)
+	}
+
 	return
 }
 
diff --git a/level/anvil/chunk.go b/level/anvil/chunk.go
index b5d50ab..cce83eb 100644
--- a/level/anvil/chunk.go
+++ b/level/anvil/chunk.go
@@ -1,5 +1,14 @@
 package anvil
 
+import (
+	"strings"
+	"unsafe"
+
+	"github.com/admin-else/strom/data"
+	"github.com/admin-else/strom/level"
+	"github.com/admin-else/strom/util"
+)
+
 type Chunk struct {
 	DataVersion      int32
 	Heightmaps       map[string][]int64
@@ -8,17 +17,64 @@ type Chunk struct {
 	Sections         []Section
 }
 
+const McPrefix = "minecraft:"
+
+func (c Chunk) ToStorage(version string) (toChunk *level.Chunk, err error) {
+	f := level.MakeBlockFormat(version)
+	toChunk = new(level.Chunk)
+
+	toChunk.Sections = make([]level.Section, len(c.Sections))
+	for i, s := range c.Sections {
+		pallete := make([]int32, len(s.BlockStates.Palette))
+		for j, p := range s.BlockStates.Palette {
+			pallete[j], err = data.StateIdFromBlocKAndStateMap(version, strings.TrimPrefix(p.Name, McPrefix), p.Properties)
+			if err != nil {
+				return
+			}
+		}
+		// this is probably fine
+		uintSlice := unsafe.Slice((*uint64)(unsafe.Pointer(unsafe.SliceData(s.BlockStates.Data))), len(s.BlockStates.Data))
+
+		toChunk.Sections[i].Blocks, err = f.Import(uintSlice, util.BpeByNum(float64(len(s.BlockStates.Palette))), pallete)
+		if err != nil {
+			return
+		}
+		toChunk.Sections[i].BlockCount = int16(level.CountStorage(toChunk.Sections[i].Blocks, 0))
+	}
+
+	for i, s := range c.Sections {
+		pallete := make([]int32, len(s.Biomes.Palette))
+		for j, p := range s.Biomes.Palette {
+			var b *data.Biome
+			b, ok := data.LookupBiomeByName(version, strings.TrimPrefix(p, McPrefix))
+			if !ok {
+				err = data.UnknownBiomeNameErr
+				return
+			}
+			pallete[j] = b.Id
+		}
+		// this is probably fine
+		uintSlice := unsafe.Slice((*uint64)(unsafe.Pointer(unsafe.SliceData(s.Biomes.Data))), len(s.Biomes.Data))
+
+		toChunk.Sections[i].Biomes, err = f.Import(uintSlice, util.BpeByNum(float64(len(s.BlockStates.Palette))), pallete)
+		if err != nil {
+			return
+		}
+	}
+	return
+}
+
 type Section struct {
 	Y           int8
 	BlockStates struct {
-		Data    []int64
+		Data    []int64 `nbt:"data,omitempty"`
 		Palette []struct {
 			Name       string
 			Properties map[string]string `nbt:"properties,omitempty"`
 		}
 	}
-	Biomes []struct {
-		Data    []int64
+	Biomes struct {
+		Data    []int64 `nbt:"data,omitempty"`
 		Palette []string
 	}
 }
diff --git a/level/storage.go b/level/storage.go
index 83fef6d..d70e958 100644
--- a/level/storage.go
+++ b/level/storage.go
@@ -255,3 +255,12 @@ func CompareStorage(a, b *Storage) bool {
 	}
 	return true
 }
+
+func CountStorage(s *Storage, v int32) (a int) {
+	for i := range s.format.Len {
+		if w, _ := s.Get(i); w == v {
+			a++
+		}
+	}
+	return
+}