#include <windows.h>
#include <d3d9.h>
#include <d3dx9.h>

#define RELEASE(x) if(x){x->Release();x=NULL;}

#define SCREEN_FPS 60
#define SCREEN_WIDTH 640
#define SCREEN_HEIGHT 480

HINSTANCE g_Inst;
HWND g_hWnd;
LPCSTR szAppName = "Direct3D";

LRESULT CALLBACK WndProc(HWND hWnd,UINT msg,UINT wParam,LONG lParam);

static int bActive = 0;
static int bFullScreen = 0;

D3DPRESENT_PARAMETERS d3dpp;
D3DFORMAT dspfmt;
LPDIRECT3D9 pD3D = NULL;
LPDIRECT3DDEVICE9 pDevice = NULL;
LPDIRECT3DTEXTURE9 pTexture = NULL;

// 頂点情報の構造体
typedef struct _D3DLVERTEX_{
  float x, y, z;
  float nx, ny, nz;
  D3DCOLOR c;
  float tu0, tv0;
}LVERTEX;

// 四角
LVERTEX ver[4] ={
  {-0.1f,  0.1f, 0.0f, 0.0f,  0.0f, -1.0f, 0xFFFFFFFF, 0.0f, 0.0f},
  {-0.1f, -0.1f, 0.0f, 0.0f,  0.0f, -1.0f, 0xFFFFFFFF, 0.0f, 1.0f},
  {0.1f, -0.1f, 0.0f, 0.0f,  0.0f, -1.0f, 0xFFFFFFFF, 1.0f, 1.0f},
  {0.1f,  0.1f, 0.0f, 0.0f,  0.0f, -1.0f, 0xFFFFFFFF, 1.0f, 0.0f}
};

// テクスチャの初期設定
int initTexture(void){
  int i, t;
  D3DLOCKED_RECT pLockedRect;
  unsigned char tex[8][8] = {
    {0, 0, 0, 1, 1, 0, 0, 0},
    {0, 0, 1, 2, 2, 1, 0, 0},
    {0, 1, 4, 8, 8, 4, 1, 0},
    {1, 2, 8, 8, 8, 8, 2, 1},
    {1, 2, 8, 8, 8, 8, 2, 1},
    {0, 1, 4, 8, 8, 4, 1, 0},
    {0, 0, 1, 2, 2, 1, 0, 0},
    {0, 0, 0, 1, 1, 0, 0, 0}
  };

  if(FAILED(D3DXCreateTexture(pDevice, 8, 8, 1, 0, D3DFMT_A8R8G8B8, D3DPOOL_MANAGED, &pTexture))){ // or D3DPOOL_SYSTEMMEM 
    return 0;
  }

  pTexture->LockRect(0, &pLockedRect, NULL, 0);

  for(t = 0; t < 8; t++){
    for(i = 0; i < 8; i++){
      unsigned char *p = (unsigned char *)pLockedRect.pBits + pLockedRect.Pitch * t + i * 4;

      p[0] = (unsigned char)100;       // b
      p[1] = (unsigned char)120;       // g
      p[2] = (unsigned char)250;       // r
      p[3] = (unsigned char)tex[t][i]; // a
    }
  }

  pTexture->UnlockRect(0);

  return 1;
}

class particle{
private:
  float x;
  float y;
  float z;
  float dx;
  float dy;
  float dz;
public:
  particle() : x(0.0f), y(0.0f), z(0.0f){};
  void init(){x = 0.0f; y = 0.0f; z = 0.0f;}
  void init(const float &dx, const float &dy, const float &dz){this->dx = dx; this->dy = dy; this->dz = dz;init();}
  void move(){x += dx; y += dy; z += dz;}
  const float &getX() const {return x;}
  const float &getY() const {return y;}
  const float &getZ() const {return z;}
  void setX(const float &x){this->x = x;}
  void setY(const float &y){this->y = y;}
  void setZ(const float &z){this->z = z;}
};

class particles{
  int p_count;
  particle *p;
  float x;
  float y;
  float z;
public:
  enum{num_p = 1024};
  particles(): p_count(0){};
  void initParticles(){p = new particle[num_p];}
  void deinitParticles(){delete [] p;}
  void startParticles(const float &x, const float &y, const float &z){
    int i;
    float ra, rb, d1;

    p_count = 0;

    this->x = x;
    this->y = y;
    this->z = z;

    for(i = 0; i < num_p; i++){
      ra = (rand() % 360) * 0.0174;
      rb = (rand() % 360) * 0.0174;
      d1 = (rand() % 100) * 0.0005 + 0.005;
      p[i].init((float)sin(ra) * d1, (float)cos(ra) * d1, (float)cos(rb) * d1);
    }
  }
  void startParticlesRandPos(){
    startParticles((rand() % 1000) * 0.001f - 0.5f , (rand() % 1000) * 0.001f - 0.5f, (rand() % 1000) * 0.001f - 0.5f);
  }
  void move(){
    int i;

    p_count++;

    for(i = 0; i < num_p; i++){
      p[i].move();
    }
  }
  const float &getX() const {return x;}
  const float &getY() const {return y;}
  const float &getZ() const {return z;}
  int getP_count() const {return p_count;}
  const particle &getP(const int n) const {return p[n];}
};

class Objects{
  particles *ps;
public:
  enum{num_ps = 4};
  void init(){
    int i;

    ps = new particles[num_ps];
  
    for(i = 0; i < num_ps; i++){
      ps[i].initParticles();
    }
  }
  const particles &getPs(const int n) const {return ps[n];}
  void startParticles(const int n){ps[n].startParticlesRandPos();}
  void move(){
    int i;

    for(i = 0; i < num_ps; i++){
      ps[i].move();
    }
  }
  void deinit(){
    int i;
  
    for(i = 0; i < num_ps; i++){
      ps[i].deinitParticles();
    }

    delete [] ps;
    ps = NULL;
  }
};

// Direct3D の初期化
int initD3D(void){
  D3DDISPLAYMODE dsp;

  pD3D = Direct3DCreate9(D3D_SDK_VERSION);

  if(pD3D == NULL){
    return 0;
  }

  // 現在のディスプレイモードを得る
  if(FAILED(pD3D->GetAdapterDisplayMode(D3DADAPTER_DEFAULT, &dsp))){
    return 0;
  }

  dspfmt = dsp.Format;

  ZeroMemory(&d3dpp, sizeof(d3dpp));

  d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;   //垂直同期でフリップ

  // フルスクリーン or ウィンドウ
  if(bFullScreen == 1){
    d3dpp.BackBufferFormat = D3DFMT_R5G6B5;
    d3dpp.Windowed = 0;
  }
  else{
    d3dpp.BackBufferFormat = dsp.Format;
    d3dpp.Windowed = 1;
  }

  d3dpp.BackBufferCount = 1;
  d3dpp.BackBufferWidth = SCREEN_WIDTH;
  d3dpp.BackBufferHeight = SCREEN_HEIGHT;
  d3dpp.EnableAutoDepthStencil = TRUE;
  d3dpp.AutoDepthStencilFormat = D3DFMT_D16;
  
  // Ｔ＆Ｌ ＨＡＬ
  if(FAILED(pD3D->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, g_hWnd, D3DCREATE_HARDWARE_VERTEXPROCESSING, &d3dpp, &pDevice))){
    // ＨＡＬ
    if(FAILED(pD3D->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL,g_hWnd, D3DCREATE_SOFTWARE_VERTEXPROCESSING, &d3dpp, &pDevice))){
      // ＨＥＬ
      if(FAILED(pD3D->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_REF, g_hWnd,D3DCREATE_SOFTWARE_VERTEXPROCESSING, &d3dpp, &pDevice))){
        return 0;
      }
    }
  }

  if(initTexture() == 0){
    return 0;
  }

  return 1;
}

// Direct3D の後片付け
void deinitD3d(void){
  RELEASE(pTexture);
  RELEASE(pDevice);
  RELEASE(pD3D);
}

// 視野の初期設定
int initView(void){
  float fAspect;
  D3DVIEWPORT9 vp;
  D3DXMATRIX mat;

  pDevice->GetViewport(&vp);
  fAspect = (float)vp.Width / (float)vp.Height;

  // Ｚ方向(視点 -1.0 手前 -0.5 中心 0.0 奥 0.5) Ｙ方向の視野角 90度
  D3DXMatrixPerspectiveFovLH(&mat, D3DXToRadian(90.0f), fAspect, 0.5f, 1.5f);
  pDevice->SetTransform(D3DTS_PROJECTION, &mat);
  D3DXMatrixLookAtLH(&mat, &D3DXVECTOR3(0.0f, 0.0f, -1.0f), &D3DXVECTOR3(0, 0, 0), &D3DXVECTOR3(0, 1, 0));
  pDevice->SetTransform(D3DTS_VIEW, &mat);

  return 1;
}

// 光源の初期設定
int initLighting(void){
  D3DMATERIAL9 mtrl;

  ZeroMemory(&mtrl, sizeof(D3DMATERIAL9));
  mtrl.Diffuse.r = 1.0f;
  mtrl.Diffuse.g = 1.0f;
  mtrl.Diffuse.b = 1.0f;
  mtrl.Diffuse.a = 1.0f;
  mtrl.Ambient.r = 1.0f;
  mtrl.Ambient.g = 1.0f;
  mtrl.Ambient.b = 1.0f;
  mtrl.Ambient.a = 1.0f;
  pDevice->SetMaterial(&mtrl);

  D3DLIGHT9 light;
 
  ZeroMemory(&light, sizeof(D3DLIGHT9));
  light.Type = D3DLIGHT_DIRECTIONAL;
  light.Diffuse.r = 1.0f;
  light.Diffuse.g = 1.0f;
  light.Diffuse.b = 1.0f;
  D3DXVECTOR3 vecDir(0.0f, 0.0f, 1.0f);
  D3DXVec3Normalize(static_cast<D3DXVECTOR3*>(&light.Direction), &vecDir);
  light.Range = 1000.0f;

  pDevice->SetLight( 0, &light );
  pDevice->LightEnable( 0, TRUE );

  pDevice->SetRenderState(D3DRS_AMBIENT, 0x00000000);
  pDevice->SetRenderState(D3DRS_LIGHTING, TRUE);

  return 1;
}

// レンダリングに関する初期設定
int initRender(void){
  // 視野の初期設定
  initView();
  // 光源の初期設定
  initLighting();
  // カリングの設定
  pDevice->SetRenderState(D3DRS_CULLMODE, D3DCULL_CW);  // NONE or CW or CCW
  // Z バッファの設定
  pDevice->SetRenderState(D3DRS_ZENABLE, TRUE);
  pDevice->SetRenderState(D3DRS_ZWRITEENABLE, TRUE);
  pDevice->SetRenderState(D3DRS_ZFUNC, D3DCMP_LESSEQUAL );
  // テクスチャの設定
  pDevice->SetSamplerState(0, D3DSAMP_MAGFILTER, D3DTEXF_NONE);
  pDevice->SetSamplerState(0, D3DSAMP_MIPFILTER, D3DTEXF_NONE);
  // αブレンドの設定
  pDevice->SetRenderState(D3DRS_ALPHABLENDENABLE, TRUE);
  pDevice->SetRenderState(D3DRS_SRCBLEND, D3DBLEND_SRCALPHA);
  pDevice->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_ONE);

  return 1;
}

// 描画本体
int drawIdle(const Objects &objs){
  // 画面を白で塗りつぶし、Ｚバッファをクリア
  pDevice->Clear(0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER , D3DCOLOR_XRGB(0,0,0), 1.0, 0);

  //頂点フォーマットの設定
  pDevice->SetFVF(D3DFVF_XYZ | D3DFVF_NORMAL | D3DFVF_DIFFUSE | D3DFVF_TEX1);  

  if(SUCCEEDED(pDevice->BeginScene())){
    D3DXMATRIX mat, mat2;
    D3DXMatrixIdentity(&mat);

    pDevice->SetRenderState(D3DRS_ZWRITEENABLE, FALSE);

    int i, t;

    for(t = 0; t < Objects::num_ps; t++){
      const particles &ps = objs.getPs(t);
      for(i = 0; i < particles::num_p; i++){
        const particle &p = ps.getP(i);

        D3DXMatrixTranslation(&mat, ps.getX() + p.getX(), ps.getY() + p.getY(), ps.getZ() + p.getZ());
        //D3DXMatrixRotationX(&mat, D3DXToRadian(45.0f));
        //D3DXMatrixRotationY(&mat, D3DXToRadian(45.0f));
        D3DXMatrixRotationZ(&mat2, D3DXToRadian(15.0f));
        //D3DXMatrixScaling(&mat2, 1.5f, 1.5f, 1.0f);
        mat *= mat2;
        pDevice->SetTransform(D3DTS_WORLD, &mat);
        pDevice->SetTexture(0, pTexture);
        pDevice->DrawPrimitiveUP(D3DPT_TRIANGLEFAN, 2, ver, sizeof(LVERTEX));
        pDevice->SetTexture(0, NULL);
      }
    }

    pDevice->SetRenderState(D3DRS_ZWRITEENABLE, TRUE);

    pDevice->EndScene();

    if(FAILED(pDevice->Present(NULL, NULL, NULL, NULL))){
      if(FAILED(pDevice->Reset(&d3dpp))){
        return 0;
      }
    }
  }

  return 1;
}

// ウィンドウプロシージャ
LRESULT CALLBACK WndProc(HWND hWnd, UINT msg, UINT wParam, LONG lParam){
  switch(msg){
  case WM_ACTIVATE:
    bActive = HIWORD(wParam)?0:1;
    break;
  case WM_KEYDOWN:
    switch(wParam){
    case VK_F3:  // F3 キーでウィンドウとフルスクリーンを入れ替え
      bFullScreen = !bFullScreen;
      if(bFullScreen == 1){
        d3dpp.BackBufferFormat = D3DFMT_R5G6B5;
        d3dpp.Windowed = 0;
      }else{
        d3dpp.BackBufferFormat = dspfmt;
        d3dpp.Windowed = 1;
      }
      if(FAILED(pDevice->Reset(&d3dpp))){
        PostMessage(hWnd, WM_CLOSE, 0, 0);
        return 0L;
      }
      initRender();
      if(bFullScreen != 1){
        DrawMenuBar(g_hWnd);
      }
      break;
    case VK_ESCAPE:
      PostMessage(hWnd, WM_CLOSE, 0, 0);
      break;
    default:
      break;
    }
    break;
  case WM_DESTROY:
    PostQuitMessage(0);
    break;
  case WM_IME_NOTIFY:
    // ＩＭＥのツールバーを非表示に
    break;
  default:
    return DefWindowProc(hWnd, msg, wParam, lParam);
  }
  return 0L;
}

// メイン
int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR lpCmdLine, int nCmdShow){
  int result;
  int cx, cy;
  WNDCLASS wc;
  MSG msg;
  DWORD waittime;

  // 256色以下のモードで起動不可
  HDC dc = GetDC(0);
  int iBit = GetDeviceCaps(dc, BITSPIXEL);
  ReleaseDC(0, dc);
  if(iBit < 15){
    MessageBox(0, "256色以下では実行できません", szAppName, MB_ICONSTOP|MB_OK);
    return 0;
  }

  g_Inst=hInst;

  if(!hPrevInst){
    wc.lpszClassName = "Direct3D";
    wc.lpfnWndProc = WndProc;
    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.hInstance = hInst;
    wc.hIcon = NULL;
    wc.hCursor = LoadCursor(NULL,IDC_ARROW);
    wc.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH);
    wc.lpszMenuName = NULL;
    wc.cbClsExtra = 0;
    wc.cbWndExtra = 0;
    if(!RegisterClass(&wc)){
      return 0;
    }
  }
  
  cx = SCREEN_WIDTH + GetSystemMetrics(SM_CXDLGFRAME) * 2;
  cy = SCREEN_HEIGHT + GetSystemMetrics(SM_CYDLGFRAME) * 2 + GetSystemMetrics(SM_CYCAPTION);

  g_hWnd = CreateWindowEx(0, szAppName, szAppName,
             WS_OVERLAPPED | WS_SYSMENU | WS_MINIMIZEBOX,
             CW_USEDEFAULT, CW_USEDEFAULT, cx, cy,
             (HWND)NULL, (HMENU)NULL,
             hInst, (LPSTR)NULL);

  ShowWindow(g_hWnd, nCmdShow);
  UpdateWindow(g_hWnd);

  Objects objs;

  result = initD3D();

  if(result == 0){
    goto fin;
  }

  result = initRender();

  if(result == 0){
    goto fin;
  }

  objs.init();

  objs.startParticles(0);
  objs.startParticles(1);
  objs.startParticles(2);
  objs.startParticles(3);

  msg.wParam = 0;

  while(1){
    waittime = GetTickCount();
    if(bActive){
      static int count = 0;

      objs.move();

      if(count % 50 == 0){
        objs.startParticles(0);
      }
      else if(count % 57 == 0){
        objs.startParticles(1);
      }
      else if(count % 66 == 0){
        objs.startParticles(2);
      }
      else if(count % 71 == 0){
        objs.startParticles(3);
      }

      count++;

      if(!drawIdle(objs)){
        goto fin;
      }
    }
    else{
      WaitMessage();
    }
    do{
      while(PeekMessage(&msg, NULL, 0, 0, PM_NOREMOVE)){
        if(!GetMessage(&msg, NULL, 0, 0)){
          goto fin;
        }
        TranslateMessage(&msg);
        DispatchMessage(&msg);
      }
    }while(GetTickCount() < waittime + SCREEN_FPS);
  }

fin:

  objs.deinit();

  deinitD3d();

  return msg.wParam;
}