filter struct using reflect

func filterEntities(s []*Entity, key string, val string) (res []*Entity) {
	val = strings.ToLower(val)

	for _, e := range s {
		switch reflect.ValueOf(e).Elem().FieldByName(key).Kind() {
		case reflect.Slice:
			imm := reflect.ValueOf(e).Elem().FieldByName(key)

			for i := 0; i < imm.Len(); i++ {
				v := imm.Index(i).String()

				if strings.ToLower(v) == val {
					res = append(res, e)
				}
			}
		case reflect.String:
			v := reflect.ValueOf(e).Elem().FieldByName(key).String()

			if strings.ToLower(v) == val {
				res = append(res, e)
			}
		}
	}

	return
}