#include <chrono>
#include <cstring>

#include "dxvk_compute.h"
#include "dxvk_device.h"
#include "dxvk_pipemanager.h"
#include "dxvk_spec_const.h"
#include "dxvk_state_cache.h"

namespace dxvk {
  
  bool DxvkComputePipelineStateInfo::operator == (const DxvkComputePipelineStateInfo& other) const {
    return std::memcmp(this, &other, sizeof(DxvkComputePipelineStateInfo)) == 0;
  }
  
  
  bool DxvkComputePipelineStateInfo::operator != (const DxvkComputePipelineStateInfo& other) const {
    return std::memcmp(this, &other, sizeof(DxvkComputePipelineStateInfo)) != 0;
  }
  
  
  DxvkComputePipeline::DxvkComputePipeline(
          DxvkPipelineManager*    pipeMgr,
    const Rc<DxvkShader>&         cs)
  : m_vkd(pipeMgr->m_device->vkd()),
    m_pipeMgr(pipeMgr), m_cs(cs) {
    cs->defineResourceSlots(m_slotMapping);

    m_slotMapping.makeDescriptorsDynamic(
      m_pipeMgr->m_device->options().maxNumDynamicUniformBuffers,
      m_pipeMgr->m_device->options().maxNumDynamicStorageBuffers);
    
    m_layout = new DxvkPipelineLayout(m_vkd,
      m_slotMapping, VK_PIPELINE_BIND_POINT_COMPUTE);
  }
  
  
  DxvkComputePipeline::~DxvkComputePipeline() {
    for (const auto& instance : m_pipelines)
      this->destroyPipeline(instance.pipeline);
  }
  
  
  VkPipeline DxvkComputePipeline::getPipelineHandle(
    const DxvkComputePipelineStateInfo& state) {
    VkPipeline newPipelineHandle = VK_NULL_HANDLE;

    { std::lock_guard<sync::Spinlock> lock(m_mutex);

      if (this->findPipeline(state, newPipelineHandle))
        return newPipelineHandle;
    
      // If no pipeline instance exists with the given state
      // vector, create a new one and add it to the list.
      newPipelineHandle = this->compilePipeline(state, m_basePipeline);
      
      // Add new pipeline to the set
      m_pipelines.push_back({ state, newPipelineHandle });
      m_pipeMgr->m_numComputePipelines += 1;
      
      if (!m_basePipeline && newPipelineHandle)
        m_basePipeline = newPipelineHandle;
    }
    
    if (newPipelineHandle != VK_NULL_HANDLE)
      this->writePipelineStateToCache(state);
    
    return newPipelineHandle;
  }
  
  
  bool DxvkComputePipeline::findPipeline(
    const DxvkComputePipelineStateInfo& state,
          VkPipeline&                   pipeline) const {
    for (const PipelineStruct& pair : m_pipelines) {
      if (pair.stateVector == state) {
        pipeline = pair.pipeline;
        return true;
      }
    }
    
    return false;
  }
  
  
  VkPipeline DxvkComputePipeline::compilePipeline(
    const DxvkComputePipelineStateInfo& state,
          VkPipeline                    baseHandle) const {
    std::vector<VkDescriptorSetLayoutBinding> bindings;

    if (Logger::logLevel() <= LogLevel::Debug) {
      Logger::debug("Compiling compute pipeline..."); 
      Logger::debug(str::format("  cs  : ", m_cs->debugName()));
    }
    
    DxvkSpecConstants specData;
    for (uint32_t i = 0; i < m_layout->bindingCount(); i++)
      specData.set(i, state.bsBindingMask.test(i), true);
    
    VkSpecializationInfo specInfo = specData.getSpecInfo();
    
    DxvkShaderModuleCreateInfo moduleInfo;
    moduleInfo.fsDualSrcBlend = false;

    auto csm = m_cs->createShaderModule(m_vkd, m_slotMapping, moduleInfo);

    VkComputePipelineCreateInfo info;
    info.sType                = VK_STRUCTURE_TYPE_COMPUTE_PIPELINE_CREATE_INFO;
    info.pNext                = nullptr;
    info.flags                = baseHandle == VK_NULL_HANDLE
      ? VK_PIPELINE_CREATE_ALLOW_DERIVATIVES_BIT
      : VK_PIPELINE_CREATE_DERIVATIVE_BIT;
    info.stage                = csm.stageInfo(&specInfo);
    info.layout               = m_layout->pipelineLayout();
    info.basePipelineHandle   = baseHandle;
    info.basePipelineIndex    = -1;
    
    // Time pipeline compilation for debugging purposes
    auto t0 = std::chrono::high_resolution_clock::now();
    
    VkPipeline pipeline = VK_NULL_HANDLE;
    if (m_vkd->vkCreateComputePipelines(m_vkd->device(),
          m_pipeMgr->m_cache->handle(), 1, &info, nullptr, &pipeline) != VK_SUCCESS) {
      Logger::err("DxvkComputePipeline: Failed to compile pipeline");
      Logger::err(str::format("  cs  : ", m_cs->debugName()));
      return VK_NULL_HANDLE;
    }
    
    auto t1 = std::chrono::high_resolution_clock::now();
    auto td = std::chrono::duration_cast<std::chrono::milliseconds>(t1 - t0);
    Logger::debug(str::format("DxvkComputePipeline: Finished in ", td.count(), " ms"));
    return pipeline;
  }


  void DxvkComputePipeline::destroyPipeline(VkPipeline pipeline) {
    m_vkd->vkDestroyPipeline(m_vkd->device(), pipeline, nullptr);
  }
  
  
  void DxvkComputePipeline::writePipelineStateToCache(
    const DxvkComputePipelineStateInfo& state) const {
    if (m_pipeMgr->m_stateCache == nullptr)
      return;
    
    DxvkStateCacheKey key;

    if (m_cs != nullptr)
      key.cs = m_cs->getShaderKey();

    m_pipeMgr->m_stateCache->addComputePipeline(key, state);
  }
  
}