better nbt error message & dimensioncodec decoder

bot/basic/info.go

@@ -4,15 +4,16 @@ import (
 	"unsafe"
 
 	"github.com/Tnze/go-mc/data/packetid"
+	"github.com/Tnze/go-mc/nbt"
 	pk "github.com/Tnze/go-mc/net/packet"
 )
 
 // WorldInfo content player info in server.
 type WorldInfo struct {
 	DimensionCodec      DimensionCodec
-	Dimension           Dimension
+	DimensionType       string
-	WorldNames          []string // Identifiers for all worlds on the server.
+	DimensionNames      []string // Identifiers for all worlds on the server.
-	WorldName           string   // Name of the world being spawned into.
+	DimensionName       string   // Name of the world being spawned into.
 	HashedSeed          int64    // First 8 bytes of the SHA-256 hash of the world's seed. Used client side for biome noise
 	MaxPlayers          int32    // Was once used by the client to draw the player list, but now is ignored.
 	ViewDistance        int32    // Render distance (2-32).
@@ -22,112 +23,52 @@ type WorldInfo struct {
 	IsDebug             bool     // True if the world is a debug mode world; debug mode worlds cannot be modified and have predefined blocks.
 	IsFlat              bool     // True if the world is a superflat world; flat worlds have different void fog and a horizon at y=0 instead of y=63.
 }
+
 type Dimension struct {
-	Name    string `nbt:"name"`
+	FixedTime          int64   `nbt:"fixed_time,omitempty"`
-	Id      int    `nbt:"id"`
+	HasSkylight        bool    `nbt:"has_skylight"`
-	Element struct {
+	HasCeiling         bool    `nbt:"has_ceiling"`
-		PiglinSafe                  byte    `nbt:"piglin_safe"`
+	Ultrawarm          bool    `nbt:"ultrawarm"`
-		Natural                     byte    `nbt:"natural"`
+	Natural            bool    `nbt:"natural"`
-		AmbientLight                float64 `nbt:"ambient_light"`
+	CoordinateScale    float64 `nbt:"coordinate_scale"`
-		MonsterSpawnBlockLightLimit int     `nbt:"monster_spawn_block_light_limit"`
+	BedWorks           bool    `nbt:"bed_works"`
-		Infiniburn                  string  `nbt:"infiniburn"`
+	RespawnAnchorWorks byte    `nbt:"respawn_anchor_works"`
-		RespawnAnchorWorks          byte    `nbt:"respawn_anchor_works"`
+	MinY               int32   `nbt:"min_y"`
-		HasSkylight                 byte    `nbt:"has_skylight"`
+	Height             int32   `nbt:"height"`
-		BedWorks                    byte    `nbt:"bed_works"`
+	LogicalHeight      int32   `nbt:"logical_height"`
-		Effects                     string  `nbt:"effects"`
+	InfiniteBurn       string  `nbt:"infiniburn"`
-		HasRaids                    byte    `nbt:"has_raids"`
+	Effects            string  `nbt:"effects"`
-		Shrunk                      byte    `nbt:"shrunk"`
+	AmbientLight       float64 `nbt:"ambient_light"`
-		LogicalHeight               int     `nbt:"logical_height"`
+
-		CoordinateScale             float64 `nbt:"coordinate_scale"`
+	PiglinSafe                  byte           `nbt:"piglin_safe"`
-		MinY                        int     `nbt:"min_y"`
+	HasRaids                    byte           `nbt:"has_raids"`
-		MonsterSpawnLightLevel      int     `nbt:"monster_spawn_light_level"`
+	MonsterSpawnLightLevel      nbt.RawMessage `nbt:"monster_spawn_light_level"` // Tag_Int or {type:"minecraft:uniform", value:{min_inclusive: Tag_Int, max_inclusive: Tag_Int}}
-		Ultrawarm                   byte    `nbt:"ultrawarm"`
+	MonsterSpawnBlockLightLimit int32          `nbt:"monster_spawn_block_light_limit"`
-		HasCeiling                  byte    `nbt:"has_ceiling"`
-		Height                      int     `nbt:"height"`
-		FixedTime                   int64   `nbt:"fixed_time,omitempty"`
-	} `nbt:"element"`
 }
+
 type DimensionCodec struct {
 	// What is Below? (wiki.vg)
-	ChatType struct {
+	ChatType      Registry[nbt.RawMessage] `nbt:"minecraft:chat_type"`
-		Type  string `nbt:"type"`
+	DimensionType Registry[Dimension]      `nbt:"minecraft:dimension_type"`
-		Value []struct {
+	WorldGenBiome Registry[nbt.RawMessage] `nbt:"minecraft:worldgen/biome"`
-			Name    string `nbt:"name"`
+}
-			Id      int    `nbt:"id"`
+
-			Element struct {
+type Registry[E any] struct {
-				Chat struct {
+	Type  string `nbt:"type"`
-					Decoration struct {
+	Value []struct {
-						TranslationKey interface{} `nbt:"translation_key"`
+		Name    string `nbt:"name"`
-						Style          struct {
+		ID      int32  `nbt:"id"`
-							Color  interface{} `nbt:"color,omitempty"`
+		Element E      `nbt:"element"`
-							Italic interface{} `nbt:"italic,omitempty"`
+	} `nbt:"value"`
-						} `nbt:"style"`
+}
-						Parameters []interface{} `nbt:"parameters"`
+
-					} `nbt:"decoration,omitempty"`
+func (r *Registry[E]) Find(name string) *E {
-				} `nbt:"chat,omitempty"`
+	for i := range r.Value {
-				Narration struct {
+		if r.Value[i].Name == name {
-					Priority   interface{} `nbt:"priority"`
+			return &r.Value[i].Element
-					Decoration struct {
+		}
-						TranslationKey interface{} `nbt:"translation_key"`
+	}
-						Style          struct {
+	return nil
-						} `nbt:"style"`
-						Parameters []interface{} `nbt:"parameters"`
-					} `nbt:"decoration,omitempty"`
-				} `nbt:"narration,omitempty"`
-				Overlay struct {
-				} `nbt:"overlay,omitempty"`
-			} `nbt:"element"`
-		} `nbt:"value"`
-	} `nbt:"minecraft:chat_type"`
-	DimensionType struct {
-		Type  string      `nbt:"type"`
-		Value []Dimension `nbt:"value"`
-	} `nbt:"minecraft:dimension_type"`
-	WorldGenBiome struct {
-		Type  string `nbt:"type"`
-		Value []struct {
-			Name    string `nbt:"name"`
-			Id      int    `nbt:"id"`
-			Element struct {
-				Precipitation interface{} `nbt:"precipitation"`
-				Effects       struct {
-					SkyColor      int `nbt:"sky_color"`
-					WaterFogColor int `nbt:"water_fog_color"`
-					FogColor      int `nbt:"fog_color"`
-					WaterColor    int `nbt:"water_color"`
-					MoodSound     struct {
-						TickDelay         int         `nbt:"tick_delay"`
-						Offset            interface{} `nbt:"offset"`
-						Sound             string      `nbt:"sound"`
-						BlockSearchExtent int         `nbt:"block_search_extent"`
-					} `nbt:"mood_sound"`
-					GrassColorModifier interface{} `nbt:"grass_color_modifier,omitempty"`
-					Music              struct {
-						ReplaceCurrentMusic interface{} `nbt:"replace_current_music"`
-						MaxDelay            int         `nbt:"max_delay"`
-						Sound               string      `nbt:"sound"`
-						MinDelay            int         `nbt:"min_delay"`
-					} `nbt:"music,omitempty"`
-					FoliageColor   int    `nbt:"foliage_color,omitempty"`
-					GrassColor     int    `nbt:"grass_color,omitempty"`
-					AmbientSound   string `nbt:"ambient_sound,omitempty"`
-					AdditionsSound struct {
-						Sound      string      `nbt:"sound"`
-						TickChance interface{} `nbt:"tick_chance"`
-					} `nbt:"additions_sound,omitempty"`
-					Particle struct {
-						Probability interface{} `nbt:"probability"`
-						Options     struct {
-							Type string `nbt:"type"`
-						} `nbt:"options"`
-					} `nbt:"particle,omitempty"`
-				} `nbt:"effects"`
-				Temperature         interface{} `nbt:"temperature"`
-				Downfall            interface{} `nbt:"downfall"`
-				TemperatureModifier interface{} `nbt:"temperature_modifier,omitempty"`
-			} `nbt:"element"`
-		} `nbt:"value"`
-	} `nbt:"minecraft:worldgen/biome"`
 }
 
 type PlayerInfo struct {
@@ -143,17 +84,15 @@ type ServInfo struct {
 }
 
 func (p *Player) handleLoginPacket(packet pk.Packet) error {
-	var WorldNames = make([]pk.Identifier, 0)
-	var currentDimension pk.Identifier
 	err := packet.Scan(
 		(*pk.Int)(&p.EID),
 		(*pk.Boolean)(&p.Hardcore),
 		(*pk.UnsignedByte)(&p.Gamemode),
 		(*pk.Byte)(&p.PrevGamemode),
-		pk.Array(&WorldNames),
+		pk.Array((*[]pk.Identifier)(unsafe.Pointer(&p.DimensionNames))),
 		pk.NBT(&p.WorldInfo.DimensionCodec),
-		&currentDimension,
+		(*pk.Identifier)(&p.WorldInfo.DimensionType),
-		(*pk.Identifier)(&p.WorldName),
+		(*pk.Identifier)(&p.DimensionName),
 		(*pk.Long)(&p.HashedSeed),
 		(*pk.VarInt)(&p.MaxPlayers),
 		(*pk.VarInt)(&p.ViewDistance),
@@ -166,18 +105,6 @@ func (p *Player) handleLoginPacket(packet pk.Packet) error {
 	if err != nil {
 		return Error{err}
 	}
-	// This line should work "like" the following code but without copy things
-	//	p.WorldNames = make([]string, len(WorldNames))
-	//	for i, v := range WorldNames {
-	//		p.WorldNames[i] = string(v)
-	//	}
-	p.WorldNames = *(*[]string)(unsafe.Pointer(&WorldNames))
-	for _, d := range p.DimensionCodec.DimensionType.Value {
-		if d.Name == string(currentDimension) {
-			p.Dimension = d
-		}
-	}
-
 	err = p.c.Conn.WritePacket(pk.Marshal( //PluginMessage packet
 		packetid.ServerboundCustomPayload,
 		pk.Identifier("minecraft:brand"),
@@ -205,10 +132,9 @@ func (p *Player) handleLoginPacket(packet pk.Packet) error {
 }
 func (p *Player) handleRespawnPacket(packet pk.Packet) error {
 	var copyMeta bool
-	var currentDimension pk.Identifier
 	err := packet.Scan(
-		&currentDimension,
+		(*pk.String)(&p.DimensionType),
-		(*pk.Identifier)(&p.WorldName),
+		(*pk.Identifier)(&p.DimensionName),
 		(*pk.Long)(&p.HashedSeed),
 		(*pk.UnsignedByte)(&p.Gamemode),
 		(*pk.Byte)(&p.PrevGamemode),
@@ -219,10 +145,5 @@ func (p *Player) handleRespawnPacket(packet pk.Packet) error {
 	if err != nil {
 		return Error{err}
 	}
-	for _, d := range p.DimensionCodec.DimensionType.Value {
-		if d.Name == string(currentDimension) {
-			p.Dimension = d
-		}
-	}
 	return nil
 }

bot/world/chunks.go

@@ -39,8 +39,8 @@ func (w *World) onPlayerSpawn(pk.Packet) error {
 
 func (w *World) handleLevelChunkWithLightPacket(packet pk.Packet) error {
 	var pos level.ChunkPos
-
+	currentDimType := w.p.WorldInfo.DimensionCodec.DimensionType.Find(w.p.DimensionType)
-	chunk := level.EmptyChunk(int(w.p.WorldInfo.Dimension.Element.Height / 16))
+	chunk := level.EmptyChunk(int(currentDimType.Height) / 16)
 	if err := packet.Scan(&pos, chunk); err != nil {
 		return err
 	}

nbt/decode.go

@@ -39,10 +39,6 @@ func (d *Decoder) Decode(v interface{}) (string, error) {
 		return tagName, fmt.Errorf("nbt: %w", err)
 	}
 
-	if c := d.checkCompressed(tagType); c != "" {
-		return tagName, fmt.Errorf("nbt: unknown Tag, maybe compressed by %s, uncompress it first", c)
-	}
-
 	// We decode val not val.Elem because the Unmarshaler interface
 	// test must be applied at the top level of the value.
 	err = d.unmarshal(val, tagType)
@@ -78,7 +74,7 @@ func (d *Decoder) unmarshal(val reflect.Value, tagType byte) error {
 
 	switch tagType {
 	default:
-		return fmt.Errorf("unknown Tag 0x%02x", tagType)
+		return fmt.Errorf("unknown Tag %#02x", tagType)
 	case TagEnd:
 		return ErrEND
 
@@ -505,7 +501,7 @@ func (d *Decoder) rawRead(tagType byte) error {
 	var buf [8]byte
 	switch tagType {
 	default:
-		return fmt.Errorf("unknown to read 0x%02x", tagType)
+		return fmt.Errorf("unknown to read %#02x", tagType)
 	case TagByte:
 		_, err := d.readByte()
 		return err
@@ -590,7 +586,12 @@ func (d *Decoder) readTag() (tagType byte, tagName string, err error) {
 		return
 	}
 
-	if tagType != TagEnd { //Read Tag
+	switch tagType {
+	case 0x1f, 0x78:
+		c := d.checkCompressed(tagType)
+		err = fmt.Errorf("nbt: unknown Tag %#02x, which seems like %s header and you should uncompress it first", tagType, c)
+	case TagEnd:
+	default: //Read Tag
 		tagName, err = d.readString()
 	}
 	return

nbt/encode.go

@@ -200,6 +200,9 @@ func (e *Encoder) writeValue(val reflect.Value, tagType byte) error {
 				if tagProps.OmitEmpty && isEmptyValue(v) {
 					continue
 				}
+				if tagProps.Type == TagNone {
+					return fmt.Errorf("encode %q error: unsupport type %v", tagProps.Name, v.Type())
+				}
 
 				if err := e.marshal(val.Field(i), tagProps.Type, tagProps.Name); err != nil {
 					return err
@@ -216,7 +219,7 @@ func (e *Encoder) writeValue(val reflect.Value, tagType byte) error {
 				}
 				tagType, tagValue := getTagType(r.Value())
 				if tagType == TagNone {
-					return errors.New("unsupported value " + tagValue.String())
+					return fmt.Errorf("encoding %q error: unsupport type %v", tagName, tagValue.Type())
 				}
 
 				if err := e.marshal(tagValue, tagType, tagName); err != nil {

net/packet/packet_test.go

@@ -109,7 +109,7 @@ func ExamplePacket_Scan_joinGame() {
 		Hardcore       pk.Boolean
 		Gamemode       pk.UnsignedByte
 		PreGamemode    pk.Byte
-		WorldNames     = make([]pk.Identifier, 0) // This cannot replace with "var WorldNames []pk.Identifier" because "nil" has no type information
+		WorldNames     = make([]pk.Identifier, 0) // This cannot replace with "var DimensionNames []pk.Identifier" because "nil" has no type information
 		DimensionCodec struct {
 			DimensionType interface{} `nbt:"minecraft:dimension_type"`
 			WorldgenBiome interface{} `nbt:"minecraft:worldgen/biome"`

server/gameplay.go

@@ -26,7 +26,7 @@ type Game struct {
 	components  []Component
 }
 
-func (g *Game) AcceptPlayer(name string, id uuid.UUID, protocol int32, conn *net.Conn) {
+func (g *Game) AcceptPlayer(name string, id uuid.UUID, profilePubKey *rsa.PublicKey, protocol int32, conn *net.Conn) {
 	conn.Close()
 }