#include "slang_handle.h"

#include "renderer.h"
#include "application/application.h"

bool slang_handle::init_slang_module(const std::string& module_name, const std::string& entry_name)
{
    spdlog::info("slang: init slang handle: module \"{}\", entry point \"{}\"", module_name.c_str(), entry_name.c_str());
    
    const auto session = application::get()->get_renderer()->get_slang_session();
    
    Slang::ComPtr<slang::IBlob> diagnostics;
    *module.writeRef() = session->loadModule(module_name.c_str(), diagnostics.writeRef());

    if (diagnostics)
    {
        spdlog::error("slang: load module \"{}\" with diagnostics: {}", module_name.c_str(), (const char*)diagnostics->getBufferPointer());
        return false;
    }
    
    auto r = module->findEntryPointByName(entry_name.c_str(), entry_point.writeRef());
    if (r != SLANG_OK)
    {
        spdlog::error("slang: can't find entry point \"{}\"", entry_name.c_str());
        return false;
    }
    
    slang::IComponentType* components[] = { module, entry_point };
    r = session->createCompositeComponentType(components, 2, program.writeRef());
    if (r != SLANG_OK)
    {
        spdlog::error("slang: create composite component type failed");
        return false;
    }

    slang::ProgramLayout* layout = program->getLayout(target_index);

    // get entry point index and shader type
    for (int i = 0; i < layout->getEntryPointCount(); ++i)
    {
        const auto entry_reflection = layout->getEntryPointByIndex(i);
        if (strcmp(entry_reflection->getName(), entry_name.c_str()) == 0)
        {
            entry_point_index_ = i;
            shader_type_ = entry_reflection->getStage();
            break;
        }
    }
    
#if _DEBUG
    spdlog::info("slang: shader type: {}", shader_type_);
    spdlog::info("================parameters================");
    
    for (int i = 0; i < layout->getParameterCount(); ++i)
    {
        slang::VariableLayoutReflection* reflection = layout->getParameterByIndex(i);
        const auto type_reflection = reflection->getTypeLayout()->getType();
        
        spdlog::info("{} {} {}; ", i, type_reflection->getName(), reflection->getName());
    }
    spdlog::info("================parameters================");
#endif
    
    spdlog::info("slang: init slang handle successfully");
    return true;
}

Slang::ComPtr<slang::IBlob> slang_handle::get_entry_point_code() const
{
    Slang::ComPtr<slang::IBlob> diagnostics;
    Slang::ComPtr<slang::IBlob> code_blob;
    program->getEntryPointCode(
        entry_point_index_,
        target_index,
        code_blob.writeRef(),
        diagnostics.writeRef());

    if (diagnostics)
    {
        spdlog::error("slang: get entry point code failed: {}", (const char*)diagnostics->getBufferPointer());
        return nullptr;
    }
    return code_blob;
}