/*     Copyright 2015-2018 Egor Yusov
 *  
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 * 
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF ANY PROPRIETARY RIGHTS.
 *
 *  In no event and under no legal theory, whether in tort (including neVkigence), 
 *  contract, or otherwise, unless required by applicable law (such as deliberate 
 *  and grossly neVkigent acts) or agreed to in writing, shall any Contributor be
 *  liable for any damages, including any direct, indirect, special, incidental, 
 *  or consequential damages of any character arising as a result of this License or 
 *  out of the use or inability to use the software (including but not limited to damages 
 *  for loss of goodwill, work stoppage, computer failure or malfunction, or any and 
 *  all other commercial damages or losses), even if such Contributor has been advised 
 *  of the possibility of such damages.
 */

#include "pch.h"

#include "FenceVkImpl.h"
#include "EngineMemory.h"
#include "RenderDeviceVkImpl.h"

namespace Diligent
{
    
FenceVkImpl :: FenceVkImpl(IReferenceCounters* pRefCounters,
                           RenderDeviceVkImpl* pRendeDeviceVkImpl,
                           const FenceDesc&    Desc,
                           bool                IsDeviceInternal) : 
    TFenceBase(pRefCounters, pRendeDeviceVkImpl, Desc, IsDeviceInternal),
    m_FencePool(pRendeDeviceVkImpl->GetLogicalDevice().GetSharedPtr())
{
}

FenceVkImpl :: ~FenceVkImpl()
{
    // Do not dispose pending fences as the pool checks that the fence
    // is signalled, while pending fences may not be.
    // The pool will be destroyed next anyway, so it makes no difference.
    m_PendingFences.clear();
}

Uint64 FenceVkImpl :: GetCompletedValue()
{
    const auto& LogicalDevice = m_pDevice->GetLogicalDevice();
    while (!m_PendingFences.empty())
    {
        auto& Value_Fence = m_PendingFences.front();
        auto status = LogicalDevice.GetFenceStatus(Value_Fence.second);
        if(status == VK_SUCCESS)
        {
            if (Value_Fence.first > m_LastCompletedFenceValue)
                m_LastCompletedFenceValue = Value_Fence.first;
            m_FencePool.DisposeFence(std::move(Value_Fence.second));
            m_PendingFences.pop_front();
        }
        else
        {
            break;
        }
    }

    return m_LastCompletedFenceValue;
}

void FenceVkImpl :: Reset(Uint64 Value)
{
    DEV_CHECK_ERR(Value >= m_LastCompletedFenceValue, "Resetting fence '", m_Desc.Name, "' to the value (", Value, ") that is smaller than the last completed value (", m_LastCompletedFenceValue, ")");
    if (Value > m_LastCompletedFenceValue)
        m_LastCompletedFenceValue = Value;
}


void FenceVkImpl :: Wait()
{
    const auto& LogicalDevice = m_pDevice->GetLogicalDevice();
    for (auto& val_fence : m_PendingFences)
    {
        while (LogicalDevice.GetFenceStatus(val_fence.second) != VK_SUCCESS)
        {
            VkFence FenceToWait = val_fence.second;
            auto res = LogicalDevice.WaitForFences(1, &FenceToWait, VK_TRUE, UINT64_MAX);
            VERIFY_EXPR(res == VK_SUCCESS); (void)res;
        }

        auto status = LogicalDevice.GetFenceStatus(val_fence.second);
        DEV_CHECK_ERR(status == VK_SUCCESS, "All pending fences must now be complete!"); (void)status;
        if (val_fence.first > m_LastCompletedFenceValue)
            m_LastCompletedFenceValue = val_fence.first;
        m_FencePool.DisposeFence(std::move(val_fence.second));
    }
    m_PendingFences.clear();
}

}
