// Copyright 2019 The Amber Authors.
//
// 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
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "src/vulkan/command_buffer.h"

#include <cassert>
#include <string>

#include "src/vulkan/command_pool.h"
#include "src/vulkan/device.h"

namespace amber {
namespace vulkan {

CommandBuffer::CommandBuffer(Device* device, CommandPool* pool)
    : device_(device), pool_(pool) {}

CommandBuffer::~CommandBuffer() {
  Reset();

  if (fence_ != VK_NULL_HANDLE)
    device_->GetPtrs()->vkDestroyFence(device_->GetVkDevice(), fence_, nullptr);

  if (command_ != VK_NULL_HANDLE) {
    device_->GetPtrs()->vkFreeCommandBuffers(
        device_->GetVkDevice(), pool_->GetVkCommandPool(), 1, &command_);
  }
}

Result CommandBuffer::Initialize() {
  VkCommandBufferAllocateInfo command_info = VkCommandBufferAllocateInfo();
  command_info.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_ALLOCATE_INFO;
  command_info.commandPool = pool_->GetVkCommandPool();
  command_info.level = VK_COMMAND_BUFFER_LEVEL_PRIMARY;
  command_info.commandBufferCount = 1;

  if (device_->GetPtrs()->vkAllocateCommandBuffers(
          device_->GetVkDevice(), &command_info, &command_) != VK_SUCCESS) {
    return Result("Vulkan::Calling vkAllocateCommandBuffers Fail");
  }

  VkFenceCreateInfo fence_info = VkFenceCreateInfo();
  fence_info.sType = VK_STRUCTURE_TYPE_FENCE_CREATE_INFO;
  if (device_->GetPtrs()->vkCreateFence(device_->GetVkDevice(), &fence_info,
                                        nullptr, &fence_) != VK_SUCCESS) {
    return Result("Vulkan::Calling vkCreateFence Fail");
  }

  return {};
}

Result CommandBuffer::BeginRecording() {
  VkCommandBufferBeginInfo command_begin_info = VkCommandBufferBeginInfo();
  command_begin_info.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO;
  command_begin_info.flags = VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT;
  if (device_->GetPtrs()->vkBeginCommandBuffer(command_, &command_begin_info) !=
      VK_SUCCESS) {
    return Result("Vulkan::Calling vkBeginCommandBuffer Fail");
  }
  guarded_ = true;

  return {};
}

Result CommandBuffer::SubmitAndReset(uint32_t timeout_ms,
  bool pipeline_runtime_layer_enabled) {
  if (device_->GetPtrs()->vkEndCommandBuffer(command_) != VK_SUCCESS)
    return Result("Vulkan::Calling vkEndCommandBuffer Fail");

  if (device_->GetPtrs()->vkResetFences(device_->GetVkDevice(), 1, &fence_) !=
      VK_SUCCESS) {
    return Result("Vulkan::Calling vkResetFences Fail");
  }

  VkSubmitInfo submit_info = VkSubmitInfo();
  submit_info.sType = VK_STRUCTURE_TYPE_SUBMIT_INFO;
  submit_info.commandBufferCount = 1;
  submit_info.pCommandBuffers = &command_;
  if (device_->GetPtrs()->vkQueueSubmit(device_->GetVkQueue(), 1, &submit_info,
                                        fence_) != VK_SUCCESS) {
    return Result("Vulkan::Calling vkQueueSubmit Fail");
  }

  guarded_ = false;

  VkResult r = device_->GetPtrs()->vkWaitForFences(
      device_->GetVkDevice(), 1, &fence_, VK_TRUE,
      static_cast<uint64_t>(timeout_ms) * 1000ULL * 1000ULL /* nanosecond */);
  if (r == VK_TIMEOUT)
    return Result("Vulkan::Calling vkWaitForFences Timeout");
  if (r != VK_SUCCESS) {
    std::string result_str;
    switch (r) {
      case VK_ERROR_OUT_OF_HOST_MEMORY:
        result_str = "OUT_OF_HOST_MEMORY";
        break;
      case VK_ERROR_OUT_OF_DEVICE_MEMORY:
        result_str = "OUT_OF_DEVICE_MEMORY";
        break;
      case VK_ERROR_DEVICE_LOST:
        result_str = "DEVICE_LOST";
        break;
      default:
        result_str = "<UNEXPECTED RESULT>";
        break;
    }
    return Result("Vulkan::Calling vkWaitForFences Fail (" + result_str + ")");
  }

    /*
  google/vulkan-performance-layers requires a call to vkDeviceWaitIdle or
  vkQueueWaitIdle in order to report the information. Since we want to be
  able to use that layer in conjunction with Amber we need to somehow
  communicate that the Amber script has completed.
  */
  if (pipeline_runtime_layer_enabled)
    device_->GetPtrs()->vkQueueWaitIdle(device_->GetVkQueue());

  if (device_->GetPtrs()->vkResetCommandBuffer(command_, 0) != VK_SUCCESS)
    return Result("Vulkan::Calling vkResetCommandBuffer Fail");

  return {};
}

void CommandBuffer::Reset() {
  if (guarded_) {
    device_->GetPtrs()->vkResetCommandBuffer(command_, 0);
    guarded_ = false;
  }
}

CommandBufferGuard::CommandBufferGuard(CommandBuffer* buffer)
    : buffer_(buffer) {
  assert(!buffer_->guarded_);
  result_ = buffer_->BeginRecording();
}

CommandBufferGuard::~CommandBufferGuard() {
  if (buffer_->guarded_)
    buffer_->Reset();
}

Result CommandBufferGuard::Submit(uint32_t timeout_ms,
  bool pipeline_runtime_layer_enabled) {
  assert(buffer_->guarded_);
  return buffer_->SubmitAndReset(timeout_ms, pipeline_runtime_layer_enabled);
}

}  // namespace vulkan
}  // namespace amber