update gen.Config.getTimeFormat internals

gen/config.go

@@ -8,6 +8,7 @@ import (
 	"time"
 
 	"github.com/alehechka/json2go/jenshared"
+	"github.com/alehechka/json2go/utils"
 )
 
 // Config presents Gen configurations.
@@ -65,45 +66,5 @@ func (c *Config) prepareOutputFileName() {
 }
 
 func (c *Config) getTimeFormat() string {
-
-	if len(c.TimeFormat) == 0 {
-		return time.RFC3339
-	}
-
-	switch c.TimeFormat {
-	case "Layout":
-		return time.Layout
-	case "ANSIC":
-		return time.ANSIC
-	case "UnixDate":
-		return time.UnixDate
-	case "RubyDate":
-		return time.RubyDate
-	case "RFC822":
-		return time.RFC822
-	case "RFC822Z":
-		return time.RFC822Z
-	case "RFC850":
-		return time.RFC850
-	case "RFC1123":
-		return time.RFC1123
-	case "RFC1123Z":
-		return time.RFC1123Z
-	case "RFC3339":
-		return time.RFC3339
-	case "RFC3339Nano":
-		return time.RFC3339Nano
-	case "Kitchen":
-		return time.Kitchen
-	case "Stamp":
-		return time.Stamp
-	case "StampMilli":
-		return time.StampMilli
-	case "StampMicro":
-		return time.StampMicro
-	case "StampNano":
-		return time.StampNano
-	default:
-		return c.TimeFormat
-	}
+	return utils.GetTimeFormat(c.TimeFormat, time.RFC3339)
 }