[IO] Use H5 type deduction machinery in writer

include/lima/io/h5/wrapper/datatype.hpp

@@ -23,6 +23,7 @@ namespace io
         {
             // clang-format off
             template <typename T> struct deduct;
+            template <> struct deduct<bool>               { static const hid_t type() { return H5T_NATIVE_HBOOL; } };
             template <> struct deduct<unsigned char>      { static const hid_t type() { return H5T_NATIVE_UINT8; } };
             template <> struct deduct<signed char>        { static const hid_t type() { return H5T_NATIVE_INT8; } };
             template <> struct deduct<char>               { static const hid_t type() { return H5T_NATIVE_INT8; } };

include/lima/io/h5/writer.hpp

@@ -63,47 +63,10 @@ namespace io
                 static const bool is_supported = false;
             };
 
-            template <>
-            struct write_support_private<std::uint8_t, boost::gil::gray_t>
+            template <typename Channel>
+            struct write_support_private<Channel, boost::gil::gray_t> : deduct<Channel>
             {
                 static const bool is_supported = true;
-                static const hid_t type() { return H5T_NATIVE_UINT8; }
-            };
-            template <>
-            struct write_support_private<std::int8_t, boost::gil::gray_t>
-                : write_support_private<std::uint8_t, boost::gil::gray_t>
-            {
-            };
-
-            template <>
-            struct write_support_private<std::uint16_t, boost::gil::gray_t>
-            {
-                static const bool is_supported = true;
-                static const hid_t type() { return H5T_NATIVE_UINT16; }
-            };
-            template <>
-            struct write_support_private<std::int16_t, boost::gil::gray_t>
-                : write_support_private<std::uint16_t, boost::gil::gray_t>
-            {
-            };
-
-            template <>
-            struct write_support_private<std::uint32_t, boost::gil::gray_t>
-            {
-                static const bool is_supported = true;
-                static const hid_t type() { return H5T_NATIVE_UINT32; }
-            };
-            template <>
-            struct write_support_private<std::int32_t, boost::gil::gray_t>
-                : write_support_private<std::uint32_t, boost::gil::gray_t>
-            {
-            };
-
-            template <>
-            struct write_support_private<float, boost::gil::gray_t>
-            {
-                static const bool is_supported = true;
-                static const hid_t type() { return H5T_NATIVE_FLOAT; }
             };
 
             template <typename View>
@@ -154,34 +117,8 @@ namespace io
 
         inline predef_datatype datatype(pixel_enum px)
         {
-            hid_t res;
-            switch (px) {
-            case pixel_enum::gray8:
-                res = H5T_NATIVE_UINT8;
-                break;
-            case pixel_enum::gray8s:
-                res = H5T_NATIVE_INT8;
-                break;
-            case pixel_enum::gray16:
-                res = H5T_NATIVE_UINT16;
-                break;
-            case pixel_enum::gray16s:
-                res = H5T_NATIVE_INT16;
-                break;
-            case pixel_enum::gray32:
-                res = H5T_NATIVE_UINT32;
-                break;
-            case pixel_enum::gray32s:
-                res = H5T_NATIVE_INT32;
-                break;
-            case pixel_enum::gray32f:
-                res = H5T_NATIVE_FLOAT;
-                break;
-            default:
-                LIMA_THROW_EXCEPTION(lima::hdf5_error("Unsupported pixel type"));
-            }
-
-            return predef_datatype(res);
+            return std::visit([](auto p) { return predef_datatype::create<typename decltype(p)::type>(); },
+                              typeof_pixel(px));
         }
 
         class writer