From 85e9018a6528a1bb5212410b760d5e276e70136b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Franz=20P=C3=B6schel?= <franz.poeschel@gmail.com>
Date: Mon, 6 May 2024 16:26:18 +0200
Subject: [PATCH] Add normalizingVariableType

---
 include/openPMD/IO/ADIOS/ADIOS2Auxiliary.hpp | 36 +--------
 src/IO/ADIOS/ADIOS2Auxiliary.cpp             | 78 ++++++++++----------
 2 files changed, 42 insertions(+), 72 deletions(-)

diff --git a/include/openPMD/IO/ADIOS/ADIOS2Auxiliary.hpp b/include/openPMD/IO/ADIOS/ADIOS2Auxiliary.hpp
index 0b279f38cb..bcf18610b5 100644
--- a/include/openPMD/IO/ADIOS/ADIOS2Auxiliary.hpp
+++ b/include/openPMD/IO/ADIOS/ADIOS2Auxiliary.hpp
@@ -95,39 +95,6 @@ namespace detail
     // we represent booleans as unsigned chars
     using bool_representation = unsigned char;
 
-    template <typename T>
-    struct ToDatatypeHelper
-    {
-        static std::string type();
-    };
-
-    template <typename T>
-    struct ToDatatypeHelper<std::vector<T>>
-    {
-        static std::string type();
-    };
-
-    template <typename T, size_t n>
-    struct ToDatatypeHelper<std::array<T, n>>
-    {
-        static std::string type();
-    };
-
-    template <>
-    struct ToDatatypeHelper<bool>
-    {
-        static std::string type();
-    };
-
-    struct ToDatatype
-    {
-        template <typename T>
-        std::string operator()();
-
-        template <int n>
-        std::string operator()();
-    };
-
     /**
      * @brief Convert ADIOS2 datatype to openPMD type.
      * @param dt
@@ -210,6 +177,9 @@ namespace detail
         }
         throw error::Internal("Control flow error: No ADIOS2 open mode.");
     }
+
+    std::string
+    normalizingVariableType(adios2::IO const &, std::string const &name);
 } // namespace detail
 
 /**
diff --git a/src/IO/ADIOS/ADIOS2Auxiliary.cpp b/src/IO/ADIOS/ADIOS2Auxiliary.cpp
index 366be2b893..ec36ce7c1b 100644
--- a/src/IO/ADIOS/ADIOS2Auxiliary.cpp
+++ b/src/IO/ADIOS/ADIOS2Auxiliary.cpp
@@ -19,6 +19,7 @@
  * If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include "openPMD/auxiliary/TypeTraits.hpp"
 #include "openPMD/config.hpp"
 #if openPMD_HAVE_ADIOS2
 #include "openPMD/Datatype.hpp"
@@ -61,45 +62,6 @@ FlushTarget flushTargetFromString(std::string const &str)
 
 namespace openPMD::detail
 {
-template <typename T>
-std::string ToDatatypeHelper<T>::type()
-{
-    return adios2::GetType<T>();
-}
-
-template <typename T>
-std::string ToDatatypeHelper<std::vector<T>>::type()
-{
-    return
-
-        adios2::GetType<T>();
-}
-
-template <typename T, size_t n>
-std::string ToDatatypeHelper<std::array<T, n>>::type()
-{
-    return
-
-        adios2::GetType<T>();
-}
-
-std::string ToDatatypeHelper<bool>::type()
-{
-    return ToDatatypeHelper<bool_representation>::type();
-}
-
-template <typename T>
-std::string ToDatatype::operator()()
-{
-    return ToDatatypeHelper<T>::type();
-}
-
-template <int n>
-std::string ToDatatype::operator()()
-{
-    return "";
-}
-
 Datatype fromADIOS2Type(std::string const &dt, bool verbose)
 {
     static std::map<std::string, Datatype> map{
@@ -272,5 +234,43 @@ Datatype attributeInfo(
         throw std::runtime_error("Unreachable!");
     }
 }
+
+namespace
+{
+    struct ToDatatype
+    {
+        template <typename T>
+        static std::string call()
+        {
+            if constexpr (std::is_same_v<T, bool>)
+            {
+                return ToDatatype::call<bool_representation>();
+            }
+            else if constexpr (
+                auxiliary::IsVector_v<T> || auxiliary::IsArray_v<T>)
+            {
+                return ToDatatype::call<typename T::value_type>();
+            }
+            else
+            {
+                return adios2::GetType<T>();
+            }
+        }
+
+        template <int>
+        static std::string call()
+        {
+            return {};
+        }
+    };
+} // namespace
+
+std::string
+normalizingVariableType(const adios2::IO &IO, const std::string &name)
+{
+    auto const &unsanitized_result = IO.VariableType(name);
+    auto openpmd_type = fromADIOS2Type(unsanitized_result);
+    return switchAdios2VariableType<ToDatatype>(openpmd_type);
+}
 } // namespace openPMD::detail
 #endif