// 기말고사11 실기문제
// 본 소스에는 버그들이 있다. 이를 수정하여 계산기가 되도록 완성하라.
// 버튼 중에 C는 클리어(0 되게), +/-는 값의 부호를 바꿈
#include <windows.h>
#include <stdio.h>
#include "resource.h"
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg,
       WPARAM wParam, LPARAM lParam);
BOOL CALLBACK DlgProc(HWND hDlg, UINT iMsg,
       WPARAM wParam, LPARAM lParam);
HINSTANCE hInst;

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
       LPSTR lpszCmdLine, int nCmdShow)
{
 HWND   hwnd;
 MSG   msg;
 WNDCLASS WndClass;     
 hInst = hInstance;
 WndClass.style = CS_HREDRAW | CS_VREDRAW;
 WndClass.lpfnWndProc = WndProc;  
 WndClass.cbClsExtra = 0;  
 WndClass.cbWndExtra = 0;  
 WndClass.hInstance = hInstance;  
 WndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
 WndClass.hCursor = LoadCursor(NULL, IDC_ARROW); 
 WndClass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH); 
 WndClass.lpszMenuName = MAKEINTRESOURCE(ID_MENU1);  
 WndClass.lpszClassName = "Window Class Name"; 
 RegisterClass(&WndClass); 
 hwnd = CreateWindow("Window Class Name",
  "기말11실기(계산기) - 이름", // 자기 이름 넣을 것
  WS_OVERLAPPEDWINDOW,
  CW_USEDEFAULT, 
  CW_USEDEFAULT, 
  CW_USEDEFAULT, 
  CW_USEDEFAULT, 
  NULL, 
  NULL, 
  hInstance, 
  NULL 
 );
 ShowWindow(hwnd, nCmdShow);
 UpdateWindow(hwnd);
 while (GetMessage(&msg, NULL, 0, 0))
 {
  TranslateMessage(&msg); 
  DispatchMessage(&msg); 
 }
 return (int)msg.wParam;
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg,
       WPARAM wParam, LPARAM lParam)    
{
 switch (iMsg)
 {
 case WM_CREATE:
  break;
 case WM_COMMAND:
  switch(LOWORD(wParam))
  {
  case ID_40002 :
   DialogBox(hInst, MAKEINTRESOURCE(IDD_DIALOG1), hwnd, DlgProc);
   break;
  }
  break;
 case WM_DESTROY:
  PostQuitMessage(0);
  break;
 }
 return DefWindowProc(hwnd, iMsg, wParam, lParam);
}

void operation(int _nOp, float* _fResult, float _fNumber)
{
 switch(_nOp)
 {
 case 0 :
  {
   *_fResult = _fNumber;
  }
  break;
 case 1 :
  {
   *_fResult += _fNumber;
  }
  break;

 case 2 :
  {
   *_fResult -= _fNumber;
  }
  break;

 case 3 :
  {
   *_fResult *= _fNumber;
  }
  break;

 case 4 :
  {
   *_fResult /= _fNumber;
  }
  break;
 }
}

BOOL CALLBACK DlgProc(HWND hDlg, UINT iMsg,
       WPARAM wParam, LPARAM lParam)
{
 int count;
 float result;
 char num[100];
 int op;
 float number;
 char answer[100]= {NULL};

 switch(iMsg)
 {
 case WM_INITDIALOG:
  count = 0;
  result = 0.0f;
  op = 0;
  return 1;
 case WM_COMMAND:
  switch (LOWORD(wParam))
  {
  case ID_BUTTON_PULS:
   number = atof(num);
   operation(op, &result, &number);
   num[0] = \'\\0\';
   count = 0;
   op = 1;
   sprintf(answer, "%f", result);
   SetDlgItemText(hDlg, IDC_DISPLAY, answer);
   break;
  case ID_BUTTON_MINUSE:
   number = atof(num);
   operation(op, &result, &number);
   num[0] = \'\\0\';
   count = 0;
   op = 2;
   sprintf(answer, "%f", result);
   SetDlgItemText(hDlg, IDC_DISPLAY, answer);
   break;

  case ID_BUTTON_MUL:
   number = atof(num);
   number = atof(num);
   operation(op, &result, &number);
   num[0] = \'\\0\';
   count = 0;
   op = 3;
   sprintf(answer, "%f", result);
   SetDlgItemText(hDlg, IDC_DISPLAY, answer);
   break;
  case ID_BUTTON_AVG:
   number = atof(num);
   operation(op, &result, &number);
   num[0] = \'\\0\';
   count = 0;
   op = 4;
   sprintf(answer, "%f", result);
   SetDlgItemText(hDlg, IDC_DISPLAY, answer);
   break;
  case ID_1 :
   {
    num[count] = \'1\';
    count++;
    num[count] = \'\\0\';
    SetDlgItemText(hDlg, IDC_DISPLAY, num);
   }
   break;
  case ID_2 :
   {
    num[count] = \'2\';
    count++;
    num[count] = \'\\0\';
    SetDlgItemText(hDlg, IDC_DISPLAY, num);
   }
   break;
  case ID_3 :
   {
    num[count] = \'3\';
    count++;
    num[count] = \'\\0\';
    SetDlgItemText(hDlg, IDC_DISPLAY, num);
   }
   break;
  case ID_4 :
   {
    num[count] = \'4\';
    count++;
    num[count] = \'\\0\';
    SetDlgItemText(hDlg, IDC_DISPLAY, num);
   }
   break;
  case ID_5 :
   {
    num[count] = \'5\';
    count++;
    num[count] = \'\\0\';
    SetDlgItemText(hDlg, IDC_DISPLAY, num);
   }
   break;
  case ID_6 :
   {
    num[count] = \'6\';
    count++;
    num[count] = \'\\0\';
    SetDlgItemText(hDlg, IDC_DISPLAY, num);
   }
   break;
  case ID_7 :
   {
    num[count] = \'7\';
    count++;
    num[count] = \'\\0\';
    SetDlgItemText(hDlg, IDC_DISPLAY, num);
   }
   break;
  case ID_8 :
   {
    num[count] = \'8\';
    count++;
    num[count] = \'\\0\';
    SetDlgItemText(hDlg, IDC_DISPLAY, num);
   }
   break;
  case ID_9 :
   {
    num[count] = \'9\';
    count++;
    num[count] = \'\\0\';
    SetDlgItemText(hDlg, IDC_DISPLAY, num);
   }
   break;
  case ID_0 :
   {
    if(count)
    {
     num[count] = \'0\';
     count++;
     num[count] = \'\\0\';
     SetDlgItemText(hDlg, IDC_DISPLAY, num);
    }
   }
   break;
  case ID_DOT :
   {
    num[count] = \'.\';
    count++;
    num[count] = \'\\0\';
    SetDlgItemText(hDlg, IDC_DISPLAY, num);
   }
   break;
  case ID_EQ :
   {
    number = atof(num);
    num[0] = \'\\0\';
    count = 0;
    operation(op, &result, &number);
    sprintf(answer, "%f", result);
    SetDlgItemText(hDlg, IDC_DISPLAY, answer);
   }
   break;
  case ID_BUTTON_EXIT:
   EndDialog(hDlg, 0);
   break;
  case IDCANCEL:
   EndDialog(hDlg, 0);
   break;
  }
  break;
 }
 return 0;
}