Fix the circle import

data/lang/downloader.go

@@ -13,6 +13,7 @@ import (
 	"regexp"
 	"strings"
 	"sync"
+	"text/template"
 )
 
 //go:generate go run $GOFILE
@@ -107,16 +108,27 @@ func readLang(name string, r io.Reader) {
 	}
 	defer f.Close()
 
-	// write code
-	_, err = fmt.Fprintf(f,
-		"// Code generated by downloader.go; DO NOT EDIT. \n"+
-			"package %s\n\n"+
-			"import \"github.com/Tnze/go-mc/chat\"\n\n"+
-			"func init() { chat.SetLanguage(Map) }\n\n"+
-			"var Map = %#v\n",
-		name, LangMap)
+	genData := struct {
+		PkgName string
+		Name    string
+		LangMap map[string]string
+	}{
+		PkgName: pName,
+		Name:    name,
+		LangMap: LangMap,
+	}
 
-	if err != nil {
+	tmpl := template.Must(template.New("code_template").Parse(
+		`// Code generated by downloader.go; DO NOT EDIT. 
+package {{.Name}}
+{{if ne .PkgName "en_us"}}
+import "github.com/Tnze/go-mc/chat"
+
+func init() { chat.SetLanguage(Map) }
+{{end}}
+var Map = {{.LangMap | printf "%#v"}}
+`))
+	if err := tmpl.Execute(f, genData); err != nil {
 		log.Fatal(err)
 	}
 }