// Листинг 2.3. Окончательный вариант оконной функции программы просмотра файлов

/*Для успещной компиляции необходимо подключить к проекту библиотеку, в которой находится тело функции createToolbarEx().
 Откроем окно свойств проекта, в диалоговом окне Solution Explorer, На подложке
Linker | Input в окне редактирования Additional Dependencies добавляем к списку
библиотечных файлов comctl32.lib.
*/

#include <commdlg.h>
#include <fstream>
#include <vector>
#include <string>
#include <commctrl.h>
TBBUTTON tbb[] =
{
{STD_FILENEW, ID_FILE_NEW, TBSTATE_ENABLED, TBSTYLE_BUTTON,0,0,0,0},
{STD_FILEOPEN, ID_FILE_OPEN,TBSTATE_ENABLED, TBSTYLE_BUTTON, 0,0,0,0},
{STD_FILESAVE, ID_FILE_SAVE,TBSTATE_ENABLED, TBSTYLE_BUTTON,0,0,0,0}
};
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	PAINTSTRUCT ps;
	HDC hdc;
    static TCHAR name[256] = _T("");;
	static OPENFILENAME file;
	std::ifstream in;
	std::ofstream out;
	static std::vector<std::string> v;
	std::vector<std::string>::iterator it;
 	std::string st;
 	int y, k;
 	static int n,length,sx,sy,cx,iVscrollPos,iHscrollPos,COUNT,MAX_WIDTH;
 	static SIZE size = {8, 16}; //Ширина и высота символа
	static HWND hWndToolBar;
	static int size_Toolbar;
    RECT rt;
	static LOGFONT lf;
	static CHOOSEFONT cf;
	static HFONT hfont;
	TEXTMETRIC tm;
	switch (message)
 	{
 	case WM_CREATE:
	   file.lStructSize = sizeof(OPENFILENAME);
       file.hInstance = hInst;
	   file.lpstrFilter = _T("Text\0*.txt\0Все файлы\0 *.*");
	   file.lpstrFile = name;
	   file.nMaxFile = 256;
	   file.lpstrInitialDir = _T(".\\");
	   file.lpstrDefExt = _T("txt");
       hWndToolBar = CreateToolbarEx(hWnd, WS_CHILD|WS_VISIBLE|CCS_TOP,1,0,
       HINST_COMMCTRL,IDB_STD_SMALL_COLOR,tbb,3,0,0,0,0,sizeof(TBBUTTON));
	   cf.lStructSize = sizeof(CHOOSEFONT);
	   cf.Flags = CF_EFFECTS | CF_INITTOLOGFONTSTRUCT | CF_SCREENFONTS;
	   cf.hwndOwner = hWnd;
	   cf.lpLogFont = &lf;
       break;
 	case WM_SIZE:
 	   sx = LOWORD(lParam);
 	   sy = HIWORD(lParam);
	   k = n - (sy - size_Toolbar)/size.cy;
	   if (k > 0) COUNT = k; else COUNT = iVscrollPos = 0;
	   SetScrollRange(hWnd, SB_VERT, 0, COUNT, FALSE);
	   SetScrollPos (hWnd, SB_VERT, iVscrollPos, TRUE);
	   k = length - sx/size.cx;
	   if (k > 0) MAX_WIDTH = k; else MAX_WIDTH = iHscrollPos = 0;
	   SetScrollRange(hWnd, SB_HORZ, 0, MAX_WIDTH, FALSE);
	   SetScrollPos(hWnd, SB_HORZ, iHscrollPos, TRUE);
	   SendMessage(hWndToolBar, TB_AUTOSIZE, 0, 0);
	   GetWindowRect(hWndToolBar, &rt);
       size_Toolbar = rt.bottom - rt.top;
	   break;

	case WM_MOUSEWHEEL:
		iVscrollPos -= (short)HIWORD(wParam)/WHEEL_DELTA;
		iVscrollPos = max(0, min(iVscrollPos, COUNT));
		SetScrollPos(hWnd, SB_VERT, iVscrollPos, TRUE);
		InvalidateRect(hWnd, NULL, TRUE);
        break;
    case WM_VSCROLL :
      switch (LOWORD(wParam))
	       {
	        case SB_LINEUP   : iVscrollPos--; break; 
    		case SB_LINEDOWN : iVscrollPos++; break;
			case SB_PAGEUP   : iVscrollPos -= sy/size.cy; break;
			case SB_PAGEDOWN : iVscrollPos += sy/size.cy; break;
    		case SB_THUMBPOSITION : iVscrollPos = HIWORD(wParam); break;
	       }
	       iVscrollPos = max(0, min(iVscrollPos, COUNT));
	       if (iVscrollPos != GetScrollPos(hWnd, SB_VERT))
	       {
		        SetScrollPos (hWnd, SB_VERT, iVscrollPos, TRUE);
		        InvalidateRect(hWnd, NULL, TRUE);
	       }
      break;
	  case WM_HSCROLL :
	    switch (LOWORD(wParam))
	       {
	            case SB_LINEUP   : iHscrollPos--; break;
	            case SB_LINEDOWN : iHscrollPos++; break;
	            case SB_PAGEUP   : iHscrollPos -= 8; break;
                case SB_PAGEDOWN : iHscrollPos += 8; break;
	            case SB_THUMBPOSITION : iHscrollPos = HIWORD(wParam); break;
	        }
	        iHscrollPos = max(0, min(iHscrollPos, MAX_WIDTH));
	        if (iHscrollPos != GetScrollPos(hWnd, SB_HORZ))
	        {
		        SetScrollPos (hWnd, SB_HORZ, iHscrollPos, TRUE);
		        InvalidateRect(hWnd, NULL, TRUE);
	        }
       break;
	   case WM_COMMAND:
		 switch (LOWORD(wParam))
		 {
		  case ID_FILE_NEW :
		    if (!v.empty()) std::vector<std::string>().swap(v);
 			n = length = 0;
 			SendMessage(hWnd, WM_SIZE, 0, sy << 16 | sx);
 			InvalidateRect(hWnd, NULL, TRUE);
 			break;
 		  case ID_FILE_OPEN :
			 file.lpstrTitle = _T("Открыть файл для чтения");
			 file.Flags = OFN_HIDEREADONLY;
			 if (!GetOpenFileName(&file)) return 1;
			 in.open(name);
			 while (getline(in,st))
			 {
				if (length < st.length()) length = st.length();
                v.push_back(st);
 			  }
 			  in.close();
 			  n = v.size();
 			  SendMessage(hWnd, WM_SIZE, 0, sy << 16 | sx);
			  InvalidateRect(hWnd,NULL,1);
 			  break;
 		  case ID_FILE_SAVE :
 			  file.lpstrTitle = _T("Открыть файл для записи");
 			  file.Flags = OFN_NOTESTFILECREATE;
 			  if (!GetSaveFileName(&file)) return 1;
 			  out.open(name);
 			  for (it = v.begin(); it != v.end(); ++it) out << *it << '\n';
 			  out.close();
			  break;
		  case ID_FONT :
			  if(ChooseFont(&cf))
			  {
				  if (hfont) DeleteObject(hfont);
				  hfont = CreateFontIndirect(&lf);
				  hdc = GetDC(hWnd);
				  SelectObject(hdc, hfont);
				  GetTextMetrics(hdc, &tm);
				  size.cx = tm.tmAveCharWidth;
				  size.cy = tm.tmHeight + tm.tmExternalLeading;
				  ReleaseDC(hWnd, hdc);
				  SendMessage(hWnd, WM_SIZE, 0, sy << 16 | sx);
				  InvalidateRect(hWnd, NULL, TRUE);
			   }
			  break;
		  case IDM_EXIT: DestroyWindow(hWnd); break;

          default: return DefWindowProc(hWnd, message, wParam, lParam);
	      }
		  break;
	case WM_PAINT:
		hdc = BeginPaint(hWnd, &ps);
		if (hfont)
		{ SelectObject(hdc, hfont);
		SetTextColor(hdc, cf.rgbColors);
		}
		for (y = size_Toolbar, it = v.begin() + iVscrollPos;
			  it!=v.end() && y < sy; ++it, y += size.cy)
			  if (iHscrollPos < it->length())
			    TabbedTextOutA(hdc, 0, y, it->data()+iHscrollPos,
				          it->length()-iHscrollPos, 0, NULL, 0);
		EndPaint(hWnd, &ps);
		break;
	case WM_DESTROY:
	  if (hfont) DeleteObject(hfont);
	   PostQuitMessage(0);
	   break;
	default: return DefWindowProc(hWnd, message, wParam, lParam);
	}
	return 0;
}