/* Copyright (c) 2021, NVIDIA CORPORATION. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
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 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *  * Neither the name of NVIDIA CORPORATION nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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#ifndef __PARTICLESYSTEM_H__
#define __PARTICLESYSTEM_H__

#include <helper_functions.h>
#include "particles_kernel.cuh"
#include "vector_functions.h"
#include "GpuArray.h"
#include "nvMath.h"

using namespace nv;

// CUDA BodySystem: runs on the GPU
class ParticleSystem {
 public:
  ParticleSystem(uint numParticles, bool bUseVBO = true, bool bUseGL = true);
  ~ParticleSystem();

  enum ParticleConfig { CONFIG_RANDOM, CONFIG_GRID, _NUM_CONFIGS };

  void step(float deltaTime);
  void depthSort();
  void reset(ParticleConfig config);

  uint getNumParticles() { return m_numParticles; }

  uint getPosBuffer() { return m_pos.getVbo(); }
  uint getVelBuffer() { return m_vel.getVbo(); }
  uint getColorBuffer() { return 0; }
  uint getSortedIndexBuffer() { return m_indices.getVbo(); }
  uint *getSortedIndices();

  float getParticleRadius() { return m_particleRadius; }

  SimParams &getParams() { return m_params; }

  void setSorting(bool x) { m_doDepthSort = x; }
  void setModelView(float *m);
  void setSortVector(float3 v) { m_sortVector = v; }

  void addSphere(uint &index, vec3f pos, vec3f vel, int r, float spacing,
                 float jitter, float lifetime);
  void discEmitter(uint &index, vec3f pos, vec3f vel, vec3f vx, vec3f vy,
                   float r, int n, float lifetime, float lifetimeVariance);
  void sphereEmitter(uint &index, vec3f pos, vec3f vel, vec3f spread, float r,
                     int n, float lifetime, float lifetimeVariance);

  void dumpParticles(uint start, uint count);
  void dumpBin(float4 **posData, float4 **velData);

 protected:  // methods
  ParticleSystem() {}

  void _initialize(int numParticlesm, bool bUseGL = true);
  void _free();

  void initGrid(vec3f start, uint3 size, vec3f spacing, float jitter, vec3f vel,
                uint numParticles, float lifetime = 100.0f);
  void initCubeRandom(vec3f origin, vec3f size, vec3f vel,
                      float lifetime = 100.0f);

 protected:  // data
  bool m_bInitialized;
  bool m_bUseVBO;
  uint m_numParticles;

  float m_particleRadius;

  GpuArray<float4> m_pos;
  GpuArray<float4> m_vel;

  // params
  SimParams m_params;

  float4x4 m_modelView;
  float3 m_sortVector;
  bool m_doDepthSort;

  GpuArray<float> m_sortKeys;
  GpuArray<uint> m_indices;  // sorted indices for rendering

  StopWatchInterface *m_timer;
  float m_time;
};

#endif  // __PARTICLESYSTEM_H__