#include "vendor.hpp"

#include <cruft/json/tree.hpp>

#include <cruft/util/std.hpp>
#include <cruft/util/log.hpp>

using cruft::vk::icd::vendor;


#define MAP_ICD_COMMANDS(FUNC,...) MAP0(FUNC,\
    vk_icdNegotiateLoaderICDInterfaceVersion,\
    vk_icdGetInstanceProcAddr,\
    vk_icdGetPhysicalDeviceProcAddr)


///////////////////////////////////////////////////////////////////////////////
template <>
cruft::vk::icd::icd_t
json::tree::io<cruft::vk::icd::icd_t>::deserialise (json::tree::node const &obj)
{
    return {
        .file_format_version = obj["file_format_version"].as_string (),
        .icd = {
            .library_path = obj["ICD"]["library_path"].as_string ().native (),
            .api_version = obj["ICD"]["api_version"].as_string (),
        },
    };
}


///////////////////////////////////////////////////////////////////////////////
vendor::vendor (icd_t const &_icd):
    vendor (cruft::library (_icd.icd.library_path))
{ ; }


//-----------------------------------------------------------------------------
vendor::vendor (::cruft::library &&_library)
  : m_library (std::move (_library))
{
    // Negotiate needs to be called before anything else. But we load all the
    // ICD calls at once for simplicity.
    #define GET(NAME) vtable.NAME = m_library.symbol<decltype(vtable.NAME)> (#NAME);
    MAP_ICD_COMMANDS (GET)
    #undef GET

    version = 2;
    switch (auto err = vtable.vk_icdNegotiateLoaderICDInterfaceVersion (&version); err) {
    case VK_ERROR_INCOMPATIBLE_DRIVER:
        static constexpr char incompatible_message[] = "Incompatible Vulkan ICD interface";
        LOG_ERROR ("%! %!", incompatible_message, version);
        throw std::runtime_error (incompatible_message);

    default:
        static constexpr char unknown_message[] = "Unknown Vulkan ICD interface response";
        LOG_ERROR (
            "%! %!",
            unknown_message,
            static_cast<std::underlying_type_t<decltype(err)>>(err)
        );

        throw std::runtime_error (unknown_message);

    case VK_SUCCESS:
        LOG_INFO ("vk::icd version %!", version);
        break;
    }

    // Only load the instance table after we've queried all the icd functions.
    itable = {
        #define LOADFN(NAME)        \
        .NAME = reinterpret_cast<   \
            decltype(itable.NAME)   \
        > (                         \
            vtable.vk_icdGetInstanceProcAddr (nullptr, #NAME)  \
        ),

        MAP_INSTANCE_COMMANDS (LOADFN)
    };
}