LevelIndex: create indexes for all parent map levels until to the top messager

cmd/protoc-gen-cpp-tableau-loader/helper/helper.go

@@ -165,50 +165,58 @@ func ParseCppClassType(md protoreflect.MessageDescriptor) string {
 	return strings.ReplaceAll(protoFullName, ".", "::")
 }
 
+func ParseLeveledMapPrefix(md protoreflect.MessageDescriptor, mapFd protoreflect.FieldDescriptor) string {
+	if mapFd.MapValue().Kind() == protoreflect.MessageKind {
+		localMsgProtoName := strings.TrimPrefix(string(mapFd.MapValue().Message().FullName()), string(md.FullName())+".")
+		return strings.ReplaceAll(localMsgProtoName, ".", "_")
+	}
+	return mapFd.MapValue().Kind().String()
+}
+
 type MapKey struct {
 	Type string
 	Name string
 }
 
-type MapKeys []MapKey
+type MapKeySlice []MapKey
 
-func (keys MapKeys) AddMapKey(newKey MapKey) MapKeys {
+func (s MapKeySlice) AddMapKey(newKey MapKey) MapKeySlice {
 	if newKey.Name == "" {
-		newKey.Name = fmt.Sprintf("key%d", len(keys)+1)
+		newKey.Name = fmt.Sprintf("key%d", len(s)+1)
 	} else {
-		for _, key := range keys {
+		for _, key := range s {
 			if key.Name == newKey.Name {
 				// rewrite to avoid name confict
-				newKey.Name = fmt.Sprintf("%s%d", newKey.Name, len(keys)+1)
+				newKey.Name = fmt.Sprintf("%s%d", newKey.Name, len(s)+1)
 				break
 			}
 		}
 	}
-	return append(keys, newKey)
+	return append(s, newKey)
 }
 
 // GenGetParams generates function parameters, which are the names listed in the function's definition.
-func (keys MapKeys) GenGetParams() string {
+func (s MapKeySlice) GenGetParams() string {
 	var params []string
-	for _, key := range keys {
+	for _, key := range s {
 		params = append(params, ToConstRefType(key.Type)+" "+key.Name)
 	}
 	return strings.Join(params, ", ")
 }
 
 // GenGetArguments generates function arguments, which are the real values passed to the function.
-func (keys MapKeys) GenGetArguments() string {
+func (s MapKeySlice) GenGetArguments() string {
 	var params []string
-	for _, key := range keys {
+	for _, key := range s {
 		params = append(params, key.Name)
 	}
 	return strings.Join(params, ", ")
 }
 
 // GenOtherArguments generates function arguments for other value of std::tie.
-func (keys MapKeys) GenOtherArguments(other string) string {
+func (s MapKeySlice) GenOtherArguments(other string) string {
 	var params []string
-	for _, key := range keys {
+	for _, key := range s {
 		params = append(params, other+"."+key.Name)
 	}
 	return strings.Join(params, ", ")
@@ -218,6 +226,10 @@ func Indent(depth int) string {
 	return strings.Repeat("  ", depth)
 }
 
+func Whitespace(count int) string {
+	return strings.Repeat(" ", count)
+}
+
 func ParseMapValueType(fd protoreflect.FieldDescriptor) string {
 	valueType := ParseCppType(fd.MapValue())
 	if fd.MapValue().Kind() == protoreflect.MessageKind {