#include <stdio.h>
#include <windows.h>

#define DIRECTINPUT_VERSION 0x0800

#include <dinput.h>

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

#define SCREEN_WIDTH 640
#define SCREEN_HEIGHT 480

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

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

int bActive = 0;

LPDIRECTINPUT8 pDI;
LPDIRECTINPUTDEVICE8 pDIKeyboad;
LPDIRECTINPUTDEVICE8 pDIMouse;

int initDInput(void){
  DIPROPDWORD dipdw;

  if(FAILED(DirectInput8Create(g_Inst, DIRECTINPUT_VERSION, IID_IDirectInput8, (void**)&pDI, NULL))){
    return 0;
  }

  // キーボードの設定
  if(FAILED(pDI->CreateDevice(GUID_SysKeyboard, &pDIKeyboad, NULL))){
    return 0; 
  }

  if(FAILED(pDIKeyboad->SetDataFormat(&c_dfDIKeyboard))){
    return 0; 
  }

  if(FAILED(pDIKeyboad->SetCooperativeLevel(g_hWnd, DISCL_FOREGROUND | DISCL_NONEXCLUSIVE))){
    return 0; 
  }

  // マウスの設定
  if(FAILED(pDI->CreateDevice(GUID_SysMouse, &pDIMouse, NULL))){
    return 0; 
  }

  if(FAILED(pDIMouse->SetDataFormat(&c_dfDIMouse2))){
    return 0; 
  } 

  if(FAILED(pDIMouse->SetCooperativeLevel(g_hWnd, DISCL_FOREGROUND | DISCL_NONEXCLUSIVE))){
    return 0; 
  }  

  dipdw.diph.dwSize = sizeof(DIPROPDWORD);
  dipdw.diph.dwHeaderSize = sizeof(DIPROPHEADER);
  dipdw.diph.dwObj = 0;
  dipdw.diph.dwHow = DIPH_DEVICE;
  dipdw.dwData = DIPROPAXISMODE_REL;  // DIPROPAXISMODE_ABS

  if(FAILED(pDIMouse->SetProperty(DIPROP_AXISMODE, &dipdw.diph))){
    return 0; 
  }
  if(pDIKeyboad)pDIKeyboad->Acquire();
  if(pDIMouse)pDIMouse->Acquire();

  return 1;
}

void deinitDInput(void){
  if(pDIKeyboad)pDIKeyboad->Unacquire();
  if(pDIMouse)pDIMouse->Unacquire();
  RELEASE(pDIKeyboad);
  RELEASE(pDIMouse);
  RELEASE(pDI);
}

LRESULT CALLBACK WndProc(HWND hWnd, UINT msg, UINT wParam, LONG lParam){
  switch(msg){
  case WM_ACTIVATE:
    bActive = HIWORD(wParam)?0:1;

    if(pDIKeyboad){
      if(WA_INACTIVE == wParam){
        pDIKeyboad->Unacquire();
        pDIMouse->Unacquire();
      }
      else{
        pDIKeyboad->Acquire();
        pDIMouse->Acquire();
      }
    }
    break;
  case WM_KEYDOWN:
    switch(wParam){
      case VK_ESCAPE:
        PostMessage(hWnd, WM_CLOSE, 0, 0);
        break;
      default:
        break;
    }
    break;
  case WM_PAINT:
    #define KEYDOWN(name, key) (name[key] & 0x80) 

    char s[64];
    char buffer[256];
    RECT rt;
    HDC hdc;
    PAINTSTRUCT ps;
    DIMOUSESTATE2 dims;

    sprintf(s, "%s", "none");

    // キーボードの状態を取得
    if(pDIKeyboad){
      pDIKeyboad->GetDeviceState(sizeof(buffer), (LPVOID)&buffer);
      if(KEYDOWN(buffer, DIK_RIGHT)){
        sprintf(s, "key:%s", "right");
      }
      else if(KEYDOWN(buffer, DIK_LEFT)){
        sprintf(s, "key:%s", "left");
      }
      else if(KEYDOWN(buffer, DIK_UP)){
        sprintf(s, "key:%s", "up");
      }
      else if(KEYDOWN(buffer, DIK_DOWN)){
        sprintf(s, "key:%s", "down");
      }
    }

    // マウスの状態を取得
    if(pDIMouse){
      pDIMouse->GetDeviceState(sizeof(DIMOUSESTATE2), (LPVOID)&dims);
      if(dims.rgbButtons[0]){
        sprintf(s, "mouse:%s", "left");
      }
      else if(dims.rgbButtons[1]){
        sprintf(s, "mouse:%s", "right");h
      }
      else if(dims.rgbButtons[2]){
        sprintf(s, "mouse:%s", "center");
      }

      if(dims.lX || dims.lY){
        sprintf(s, "mouse(x,y):(%d,%d)", dims.lX, dims.lY);
      }
      else if(dims.lZ){
        sprintf(s, "mouse(z):%d", dims.lZ);
      }
    }

    hdc = BeginPaint (hWnd, &ps);
    GetClientRect(hWnd, &rt);
    DrawText(hdc, s, strlen(s), &rt, DT_CENTER);
    EndPaint(hWnd, &ps);

    break;
  case WM_DESTROY:
    PostQuitMessage(0);
    break;
  case WM_IME_NOTIFY:
    //
    break;
  default:
    return DefWindowProc(hWnd, msg, wParam, lParam);
  }
  return 0L;
}

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

  g_Inst=hInst;

  if(!hPrevInst){
    wc.lpszClassName = "DirectInput";
    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(WHITE_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);

  result = initDInput();

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

  while(GetMessage(&msg, NULL, 0, 0)){
    InvalidateRect(g_hWnd, NULL, TRUE);

    TranslateMessage(&msg);
    DispatchMessage(&msg);
  }

fin:

  deinitDInput();

  return msg.wParam;
}