feat: description file for custom theme; use gjson (#433)

* feat: description file for custom theme; use gjson

* fix gosec

* remove outdated stuff

pkg/utils/gjson.go

@@ -0,0 +1,36 @@
+package utils
+
+import (
+	"errors"
+
+	"github.com/tidwall/gjson"
+)
+
+var (
+	ErrGjsonNotFound  = errors.New("specified path does not exist")
+	ErrGjsonWrongType = errors.New("wrong type")
+)
+
+func GjsonGet(json []byte, path string) (gjson.Result, error) {
+	result := gjson.GetBytes(json, path)
+	if !result.Exists() {
+		return result, ErrGjsonNotFound
+	}
+
+	return result, nil
+}
+
+func GjsonParseStringMap(jsonObject string) (map[string]string, error) {
+	result := gjson.Parse(jsonObject)
+	if !result.IsObject() {
+		return nil, ErrGjsonWrongType
+	}
+
+	ret := make(map[string]string)
+	result.ForEach(func(key, value gjson.Result) bool {
+		ret[key.String()] = value.String()
+		return true
+	})
+
+	return ret, nil
+}