/*
 * Copyright (c) 2014-2021, NVIDIA CORPORATION.  All rights reserved.
 *
 * 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.
 *
 * SPDX-FileCopyrightText: Copyright (c) 2014-2021 NVIDIA CORPORATION
 * SPDX-License-Identifier: Apache-2.0
 */

#pragma once

#include "nvvkhl/appbase_vk.hpp"
#include "nvvk/debug_util_vk.hpp"
#include "nvvk/resourceallocator_vk.hpp"
#include "shaders/host_device.h"

// #VKRay
#include "nvvk/raytraceKHR_vk.hpp"
#include "offscreen.hpp"

#include "obj.hpp"
#include "raytrace.hpp"

#include <memory>

// Choosing the allocator to use
#define ALLOC_DMA
//#define ALLOC_DEDICATED
//#define ALLOC_VMA
#include <nvvk/resourceallocator_vk.hpp>

#if defined(ALLOC_DMA)
#include <nvvk/memallocator_dma_vk.hpp>
using Allocator = nvvk::ResourceAllocatorDma;
#elif defined(ALLOC_VMA)
#include <nvvk/memallocator_vma_vk.hpp>
using Allocator = nvvk::ResourceAllocatorVma;
#else
using Allocator = nvvk::ResourceAllocatorDedicated;
#endif


//--------------------------------------------------------------------------------------------------
// Simple rasterizer of OBJ objects
// - Each OBJ loaded are stored in an `ObjModel` and referenced by a `ObjInstance`
// - It is possible to have many `ObjInstance` referencing the same `ObjModel`
// - Rendering is done in an offscreen framebuffer
// - The image of the framebuffer is displayed in post-process in a full-screen quad
//
class HelloVulkan : public nvvkhl::AppBaseVk
{
public:
  void setup(const VkInstance& instance, const VkDevice& device, const VkPhysicalDevice& physicalDevice, uint32_t queueFamily) override;
  void createDescriptorSetLayout();
  void createGraphicsPipeline();
  void loadModel(const std::string& filename, nvmath::mat4f transform = nvmath::mat4f(1));
  void updateDescriptorSet();
  void createUniformBuffer();
  void createObjDescriptionBuffer();
  void createTextureImages(const VkCommandBuffer& cmdBuf, const std::vector<std::string>& textures);
  void updateUniformBuffer(const VkCommandBuffer& cmdBuf);
  void onResize(int /*w*/, int /*h*/) override;
  void destroyResources();
  void rasterize(const VkCommandBuffer& cmdBuff);

  Offscreen& offscreen() { return m_offscreen; }
  Raytracer& raytracer() { return m_raytrace; }


  // Information pushed at each draw call
  PushConstantRaster m_pcRaster{
      {1},                 // Identity matrix
      {10.f, 15.f, 8.f},   // light position
      0,                   // instance Id
      {-1.f, -1.f, -.4f},  // lightDirection;
      0.939692621f,        // {cos(deg2rad(20.0f))},  // lightSpotCutoff;
      0.866025404f,        // {cos(deg2rad(30.0f))},  // lightSpotOuterCutoff;
      100.f,               // light intensity
      0                    // light type
  };

  // Array of objects and instances in the scene
  std::vector<ObjModel>    m_objModel;   // Model on host
  std::vector<ObjDesc>     m_objDesc;    // Model description for device access
  std::vector<ObjInstance> m_instances;  // Scene model instances


  // Graphic pipeline
  VkPipelineLayout            m_pipelineLayout;
  VkPipeline                  m_graphicsPipeline;
  nvvk::DescriptorSetBindings m_descSetLayoutBind;
  VkDescriptorPool            m_descPool;
  VkDescriptorSetLayout       m_descSetLayout;
  VkDescriptorSet             m_descSet;

  int  m_maxFrames{500};
  void resetFrame();
  void updateFrame();

  nvvk::Buffer m_bGlobals;  // Device-Host of the camera matrices
  nvvk::Buffer m_bObjDesc;  // Device buffer of the OBJ descriptions

  std::vector<nvvk::Texture> m_textures;  // vector of all textures of the scene


  Allocator       m_alloc;  // Allocator for buffer, images, acceleration structures
  nvvk::DebugUtil m_debug;  // Utility to name objects

  // #Post
  Offscreen m_offscreen;
  void      initOffscreen();


  // #VKRay
  Raytracer m_raytrace;

  void initRayTracing();
  void raytrace(const VkCommandBuffer& cmdBuf, const nvmath::vec4f& clearColor);

  // Implicit
  ImplInst m_implObjects;

  void addImplSphere(nvmath::vec3f center, float radius, int matId);
  void addImplCube(nvmath::vec3f minumum, nvmath::vec3f maximum, int matId);
  void addImplMaterial(const MaterialObj& mat);
  void createImplictBuffers();
};