#include "MxlInstanceCache.hpp"

#if MXL_MULTIVIEWER_ENABLE_MXL_SDK

#include <mxl/mxl.h>

#include <algorithm>
#include <iostream>

MxlInstanceCache& MxlInstanceCache::instance()
{
    static MxlInstanceCache cache;
    return cache;
}

MxlInstanceHandle* MxlInstanceCache::acquire(
    const std::string& domain,
    bool verbose)
{
    for (auto& handle : m_handles)
    {
        if (handle.domain == domain)
        {
            ++handle.refCount;
            return &handle;
        }
    }

    mxlInstance inst = mxlCreateInstance(domain.c_str(), nullptr);
    if (!inst)
    {
        return nullptr;
    }

    if (verbose)
    {
        std::cerr << "MxlInstanceCache: created instance for domain: "
                  << domain << std::endl;
    }

    MxlInstanceHandle handle;
    handle.instance = inst;
    handle.domain = domain;
    handle.refCount = 1;

    m_handles.push_back(handle);

    return &m_handles.back();
}

void MxlInstanceCache::release(MxlInstanceHandle* handle)
{
    if (!handle)
    {
        return;
    }

    --handle->refCount;

    if (handle->refCount <= 0)
    {
        mxlDestroyInstance(handle->instance);
        handle->instance = nullptr;

        m_handles.erase(
            std::remove_if(
                m_handles.begin(),
                m_handles.end(),
                [](const MxlInstanceHandle& h)
                { return h.instance == nullptr; }),
            m_handles.end());
    }
}

#else

MxlInstanceCache& MxlInstanceCache::instance()
{
    static MxlInstanceCache cache;
    return cache;
}

MxlInstanceHandle* MxlInstanceCache::acquire(const std::string&, bool)
{
    return nullptr;
}

void MxlInstanceCache::release(MxlInstanceHandle*)
{
}

#endif