Add item DataComponent implements (part 1)

level/component/rarity.go

@@ -0,0 +1,33 @@
+package component
+
+import (
+	"io"
+
+	pk "github.com/Tnze/go-mc/net/packet"
+)
+
+var _ DataComponent = (*Rarity)(nil)
+
+type Rarity int32
+
+const (
+	Common Rarity = iota
+	Uncommon
+	Rare
+	Epic
+)
+
+// ID implements DataComponent.
+func (Rarity) ID() string {
+	return "minecraft:rarity"
+}
+
+// ReadFrom implements DataComponent.
+func (r *Rarity) ReadFrom(reader io.Reader) (n int64, err error) {
+	return (*pk.VarInt)(r).ReadFrom(reader)
+}
+
+// WriteTo implements DataComponent.
+func (r *Rarity) WriteTo(writer io.Writer) (n int64, err error) {
+	return (*pk.VarInt)(r).WriteTo(writer)
+}