Move decode of complex packets into their own package

net/ptypes/chunk.go

@@ -0,0 +1,110 @@
+// Package ptypes implements encoding and decoding for high-level packets.
+package ptypes
+
+import (
+	"bytes"
+	"fmt"
+
+	"github.com/Tnze/go-mc/nbt"
+	pk "github.com/Tnze/go-mc/net/packet"
+)
+
+// ChunkData is a clientbound packet which describes a chunk.
+type ChunkData struct {
+	X, Z           pk.Int
+	FullChunk      pk.Boolean
+	PrimaryBitMask pk.VarInt
+	Heightmaps     struct{}
+	Biomes         biomesData
+	Data           chunkData
+	BlockEntities  blockEntities
+}
+
+func (p *ChunkData) Decode(pkt pk.Packet) error {
+	r := bytes.NewReader(pkt.Data)
+	if err := p.X.Decode(r); err != nil {
+		return fmt.Errorf("X: %v", err)
+	}
+	if err := p.Z.Decode(r); err != nil {
+		return fmt.Errorf("Z: %v", err)
+	}
+	if err := p.FullChunk.Decode(r); err != nil {
+		return fmt.Errorf("full chunk: %v", err)
+	}
+	if err := p.PrimaryBitMask.Decode(r); err != nil {
+		return fmt.Errorf("bit mask: %v", err)
+	}
+	if err := (pk.NBT{V: &p.Heightmaps}).Decode(r); err != nil {
+		return fmt.Errorf("heightmaps: %v", err)
+	}
+
+	// Biome data is only present for full chunks.
+	if p.FullChunk {
+		if err := p.Biomes.Decode(r); err != nil {
+			return fmt.Errorf("heightmaps: %v", err)
+		}
+	}
+
+	if err := p.Data.Decode(r); err != nil {
+		return fmt.Errorf("data: %v", err)
+	}
+	if err := p.BlockEntities.Decode(r); err != nil {
+		return fmt.Errorf("block entities: %v", err)
+	}
+	return nil
+}
+
+type biomesData struct {
+	data []pk.VarInt
+}
+
+func (b *biomesData) Decode(r pk.DecodeReader) error {
+	var nobd pk.VarInt // Number of Biome Datums
+	if err := nobd.Decode(r); err != nil {
+		return err
+	}
+	b.data = make([]pk.VarInt, nobd)
+
+	for i := 0; i < int(nobd); i++ {
+		var d pk.VarInt
+		if err := d.Decode(r); err != nil {
+			return err
+		}
+		b.data[i] = d
+	}
+
+	return nil
+}
+
+type chunkData []byte
+type blockEntities []blockEntity
+type blockEntity struct{}
+
+// Decode implement net.packet.FieldDecoder
+func (c *chunkData) Decode(r pk.DecodeReader) error {
+	var sz pk.VarInt
+	if err := sz.Decode(r); err != nil {
+		return err
+	}
+	*c = make([]byte, sz)
+	if _, err := r.Read(*c); err != nil {
+		return err
+	}
+	return nil
+}
+
+// Decode implement net.packet.FieldDecoder
+func (b *blockEntities) Decode(r pk.DecodeReader) error {
+	var sz pk.VarInt // Number of BlockEntities
+	if err := sz.Decode(r); err != nil {
+		return err
+	}
+	*b = make(blockEntities, sz)
+	decoder := nbt.NewDecoder(r)
+	for i := 0; i < int(sz); i++ {
+		if err := decoder.Decode(&(*b)[i]); err != nil {
+			return err
+		}
+	}
+	return nil
+}