return FALSE; // ERR

			// autosel next pair
			if (pp->x - uxCurPair - 2*uFontWidth > uFontWidth / 2)
			{
				++uPair;
				uxCurPair += DIGIT_PAIR_WIDTH;
			}
		}

		// out of range?
		if (IsOutOfRange(stat.dwCurOffset + uLine * 16 + uPair))
			return FALSE; // ERR		

		// x -> LOWORD ?
		ppos->bHiword = ((UINT)pp->x > uxCurPair + uFontWidth) ? FALSE: TRUE;

		// save offset
		ppos->dwOffset = stat.dwCurOffset + uLine * 16 + uPair;
		
		return TRUE; // OK
	}
	// in text field ?
	else if ((DWORD)pp->x >= CHARS_X &&
		     (DWORD)pp->x <  CHARS_X + uFontWidth * 16 &&
			 //(DWORD)pp->y < uMaxLines * uFontHeight + iyHETop)
			 (DWORD)pp->y >= iyHETop &&
			 (DWORD)pp->y <  iyHETop + uMaxLines * uFontHeight)
	{
		uLine =  ((DWORD)pp->y - iyHETop) / uFontHeight;
		uPair =  (UINT)pp->x - CHARS_X;
		uPair /= uFontWidth;

		// out of range?
		if (IsOutOfRange(stat.dwCurOffset + uLine * 16 + uPair))
			return FALSE; // ERR

		// build output
		ppos->bTextSection = TRUE;
		ppos->bHiword      = TRUE;
		ppos->dwOffset     = stat.dwCurOffset + uLine * 16 + uPair;

		return TRUE; // OK
	}
	else
		return FALSE; // ERR
}

//
// cursor key,... handling
//
BOOL HexEditWnd::HEHandleWM_KEYDOWN(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	HE_POS  posNew;
	int     iNewLine;
	DWORD   dwOff;

	// caret already set
	if (!stat.bCaretPosValid)
		return FALSE; // ERR

	//
	// handle special keys
	//

	// tab key
	switch(wParam)
	{
	case VK_TAB:
		// switch between text/data fields
		if (stat.bCaret)
		{
			// kill sel
			if (stat.bSel)
				KillSelection();

			// reset caret
			stat.posCaret.bTextSection ^= TRUE;
			stat.posCaret.bHiword       = TRUE;
			SetCaret();

			// make visible if is not
			if (!IsOffsetVisible(stat.posCaret.dwOffset))
				SetTopLine();

			return TRUE; // OK
		}
		else
			return FALSE; // ERR
	}

	// shift key
	if ( IsKeyDown(VK_SHIFT) )
	{
		posNew = stat.posCaret;
		switch(wParam)
		{
		case VK_LEFT:    // left
			posNew.dwOffset--;
			break;

		case VK_RIGHT:   // right
			posNew.dwOffset++;
			break;

		case VK_NEXT:    // page down
			posNew.dwOffset += uMaxLines * 16;
			break;

		case VK_PRIOR:   // page up
			posNew.dwOffset -= uMaxLines * 16;
			break;

		case VK_DOWN:    // down
			posNew.dwOffset += 16;
			break;

		case VK_UP:      // up
			posNew.dwOffset -= 16;
			break;

		default:
			return FALSE; // ERR
		}

		// validate
		if (ValidatePos(&posNew))
			Beep();

		if (stat.bSel)
		{
			if (stat.dwOffSelStart == stat.posCaret.dwOffset)
				dwOff = stat.dwOffSelEnd;
			else
				dwOff = stat.dwOffSelStart;

			SetSelection( dwOff, posNew.dwOffset);
		}
		else
			SetSelection( stat.posCaret.dwOffset, posNew.dwOffset );

		SetCaret(&posNew);
		MakeCaretVisible();

		return TRUE; // OK
	}

	//
	// move caret in HE area / move current line
	//
	posNew    = stat.posCaret;
	iNewLine  = GetCurrentLine();
	switch(wParam)
	{
	case VK_NEXT:    // page down
		posNew.dwOffset += uMaxLines * 16;
		iNewLine += uMaxLines;
		break;

	case VK_PRIOR:   // page up
		posNew.dwOffset -= uMaxLines * 16;
		iNewLine -= uMaxLines;
		break;

	case VK_DOWN:    // down
		posNew.dwOffset += 16;
		++iNewLine;
		break;

	case VK_UP:      // up
		posNew.dwOffset -= 16;
		--iNewLine;
		break;

	case VK_RIGHT:   // rigth
		if (stat.posCaret.bTextSection)
		{
			++posNew.dwOffset;
			posNew.bHiword = TRUE;
		}
		else
		{
			posNew.bHiword ^= 1;	
			if (!stat.posCaret.bHiword)
				++posNew.dwOffset;
		}
		break;

	case VK_LEFT:    // left
		if (stat.posCaret.bTextSection)
		{
			--posNew.dwOffset;
			posNew.bHiword = TRUE;
		}
		else
		{
			posNew.bHiword ^= 1;
			if (stat.posCaret.bHiword)
				--posNew.dwOffset;
		}
		break;

	case VK_BACK:
		if (stat.posCaret.bTextSection)
			--posNew.dwOffset;
		break;

	default:
		return FALSE; // ERR
	}

	// changes -> GUI
	if (stat.bSel &&
		wParam != VK_RIGHT && 
		wParam != VK_LEFT)
	{
		// validate
		if (ValidateLine(&iNewLine))
			Beep();

		// set
		SetCurrentLine(iNewLine);
	}
	else
	{
		// validate
		if (ValidatePos(&posNew))
			Beep();

		// set
		KillSelection();
		SetCaret(&posNew);
		MakeCaretVisible();
	}

	return TRUE; // OK
}

//
// if caret isn't in the visible area, the top line is reset
//
// returns:
// whether it was needed to reset the top line
//
BOOL HexEditWnd::MakeCaretVisible()
{
	DWORD dwLastVisibleOff;

	if (IsOffsetVisible(stat.posCaret.dwOffset))
		return FALSE; // ERR

	dwLastVisibleOff = __min(uMaxLines * 16 + stat.dwCurOffset,
		                     diData.dwSize);
	if (stat.posCaret.dwOffset < stat.dwCurOffset) // caret above ?
		SetTopLine((int)(stat.posCaret.dwOffset / 16));
	else // caret below
		SetTopLine((int)(stat.posCaret.dwOffset / 16 - uMaxLines + 1));

	return TRUE; // OK
}

//
// corrects the information in a given HE_POS structure if it's out of range
//
// returns:
// whether sth was fixed
//
BOOL HexEditWnd::ValidatePos(PHE_POS ppos)
{
	if ((int)ppos->dwOffset < 0)
	{
		ppos->dwOffset = 0;
		ppos->bHiword  = TRUE;
		return TRUE; // OK
	}
	else if (ppos->dwOffset >= diData.dwSize)
	{
		ppos->dwOffset = diData.dwSize - 1;
		ppos->bHiword  = FALSE;
		return TRUE; // OK
	}
	else
		return FALSE; // ERR
}

//
// returns:
// last caret status
//
BOOL HexEditWnd::SetCaretSet(BOOL bSet)
{
	BOOL bRet;

	bRet = stat.bCaret;
	stat.bCaret = bSet;

	return bRet;
}

//
// set the V scrollbar range relative to "diData.dwSize"
//
void HexEditWnd::SetupVScrollbar()
{
	DWORD dwTotalLines = GetTotalLineNum();

	SetScrollRange(hMainWnd, SB_VERT, 0, (int)(dwTotalLines - 1), TRUE);

	return;
}

UINT HexEditWnd::GetTotalLineNum()
{
	DWORD dwTotalLines;

	dwTotalLines = diData.dwSize / 16;
	if (diData.dwSize % 16)
		++dwTotalLines;

	return dwTotalLines;
}

//
// handles V scrollbar movement
//
BOOL HexEditWnd::HEHandleWM_VSCROLL(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	int          nPos;
	SCROLLINFO   scrollinfo = { sizeof(SCROLLINFO) };

	nPos = GetScrollPos(hWnd, SB_VERT);

	switch(LOWORD(wParam))
	{
	case SB_THUMBPOSITION:
	case SB_THUMBTRACK:
		// get the tracking position
		scrollinfo.fMask = SIF_TRACKPOS;
		GetScrollInfo(hWnd, SB_VERT, &scrollinfo);
		nPos = scrollinfo.nTrackPos;
		break;

	case SB_TOP:
		nPos = 0;
		break;

	case SB_BOTTOM:
		nPos = GetTotalLineNum() - 1;
		break;

	case SB_LINEDOWN:
		++nPos;
		break;

	case SB_LINEUP:
		--nPos;
		break;

	case SB_PAGEDOWN:
		nPos += uMaxLines;		
		break;

	case SB_PAGEUP:
		nPos -= uMaxLines;
		break;		
	}

	return SetTopLine((int)nPos);
}

//
// sets the line to the top of the visible data range
//
BOOL HexEditWnd::SetTopLine(int iNewLine)
{
	int nNewPos;

	nNewPos = iNewLine;

	// validation
	if (nNewPos < 0)
		nNewPos = 0;
	nNewPos = __min(nNewPos, (int)GetTotalLineNum() - 1);

	// avoid repainting ?
	if (nNewPos == stat.iLastLine)
		return TRUE; // OK

	// set new line
	SetScrollPos(hMainWnd, SB_VERT, nNewPos, TRUE);
	stat.iLastLine = nNewPos;

	// set new offset
	stat.dwCurOffset = nNewPos * 16;

	// reset caret
	if (stat.bCaretPosValid)
		SetCaret();

	// repaint
	RepaintClientArea();

	return TRUE; // OK
}

//
// overloaded
//
BOOL HexEditWnd::SetTopLine(DWORD dwOffset)
{
	return SetTopLine( (int)dwOffset / 16);
}

//
// overloaded
//
BOOL HexEditWnd::SetTopLine()
{
	return SetTopLine((DWORD)stat.posCaret.dwOffset);
}

void HexEditWnd::RepaintClientArea()
{
	InvalidateRect(hMainWnd, NULL, FALSE);

	return;
}

void HexEditWnd::RepaintClientAreaNow()
{
	RepaintClientArea();
	UpdateWindow(hMainWnd);

	return;
}

void HexEditWnd::HEHandleWM_MOUSEWHEEL(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	int         nPos;
	short int   iDelta;

	iDelta = (int)HIWORD(wParam);
	nPos = GetScrollPos(hWnd, SB_VERT);
	if (iDelta > 0)
	{
		// move up	
		nPos -= WHEEL_MOVE_STEPS;
	}
	else
	{
		// move down
		nPos += WHEEL_MOVE_STEPS;
	}

	SetTopLine((int)nPos);

	return;
}

void HexEditWnd::HEHandleWM_SHOWWINDOW(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	HEdit.HESetFont(HEdit.hFont);
	SetupVScrollbar();
	ConfigureTB();
	SetHEWndCaption();

	return;
}

void HexEditWnd::Beep()
{
	MessageBeep(MB_ICONEXCLAMATION);

	return;
}

BOOL HexEditWnd::HEHandleWM_COMMAND(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	switch(LOWORD(wParam))
	{
	case TB_GOTO:
		if (DialogBoxParam(	GetInstance(), (PSTR)IDD_GOTO, hWnd, GotoDlgProc, 0) &&
			stat.bCaretPosValid)
		{
			SetTopLine();
			SetCaret(&stat.posCaret);
		}
		return TRUE;

	case TB_SELBLOCK:
		DialogBoxParam( GetInstance(), (PSTR)IDD_SELBLOCK, hWnd, SelBlockDlgProc, 0);
		return TRUE;

	case TB_SELALL:
		SelectAll();
		return TRUE;

	case TB_SEARCH:
		DialogBoxParam( GetInstance(), (PSTR)IDD_SEARCH, hWnd, SearchDlgProc, 0);
		return TRUE;

	case TB_SEARCHDOWN:
	case TB_SEARCHUP:
		PerformSearchAgain(&search, LOWORD(wParam) == TB_SEARCHDOWN ? TRUE : FALSE);
		return TRUE;

	case TB_WIN2TOP:
		SetHEWnd2Top( bHEOnTop ^ 1 );
		ConfigureTB();
		return TRUE;

	case TB_SAVE:
		SaveChanges();
		return TRUE;

	case TB_UNDO:
		UndoChanges();
		return TRUE;

	case TB_CUT:
		CutSelectedBlock();
		return TRUE;
		
	case TB_COPY:
		CopySelectedBlock();
		return TRUE;

	case TB_PASTE:
		PasteBlockFromCB();
		return TRUE;

	case TB_ABOUT:
		ShowAbout();
		return TRUE;

	case TB_CLOSE:
		HEditQuit();
		return TRUE;

	//
	// tray menu commands (IDT_XXX)
	//
	case IDT_RESTORE:
		HEditReturnFromTray();
		return TRUE;

	case IDT_EXIT:
		HEditKillTrayIcon();
		HEditQuit();
		return TRUE;
	}

	return FALSE; // ERR
}

BOOL HexEditWnd::HEHandleWM_NOTIFY(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	//
	// offer TB tooltips
	//
	if (((LPNMHDR)lParam)->code == TTN_NEEDTEXT)
	{
		switch(((LPNMHDR) lParam)->idFrom)
		{
		case TB_SAVE:
			((LPTOOLTIPTEXT)lParam)->lpszText = "save changes  ( STR+S )";
			return TRUE;

		case TB_UNDO:
			((LPTOOLTIPTEXT)lParam)->lpszText = "undo all unsaved changes  ( STR+Z )";
			return TRUE;

		case TB_GOTO:
			((LPTOOLTIPTEXT)lParam)->lpszText = "goto offset  ( STR+G )";
			return TRUE;

		case TB_SELBLOCK:
			((LPTOOLTIPTEXT)lParam)->lpszText = "select block  ( STR+B )";
			return TRUE;
			
		case TB_SELALL:
			if ( IsAllSelected() )
				((LPTOOLTIPTEXT)lParam)->lpszText = "deselect all  ( STR+A )";
			else
				((LPTOOLTIPTEXT)lParam)->lpszText = "select all  ( STR+A )";
			return TRUE;

		case TB_SEARCH:
			((LPTOOLTIPTEXT)lParam)->lpszText = "search  ( STR+F )";
			return TRUE;

		case TB_SEARCHDOWN:
			((LPTOOLTIPTEXT)lParam)->lpszText = "search down again  ( ALT+D )";
			return TRUE;

		case TB_SEARCHUP:
			((LPTOOLTIPTEXT)lParam)->lpszText = "search up again  ( ALT+U )";
			return TRUE;

		case TB_CUT:
			((LPTOOLTIPTEXT)lParam)->lpszText = "cut into clipboard  ( STR+X )";
			return TRUE;

		case TB_COPY:
			((LPTOOLTIPTEXT)lParam)->lpszText = "copy to clipboard  ( STR+C )";
			return TRUE;

		case TB_PASTE:
			((LPTOOLTIPTEXT)lParam)->lpszText = "paste from clipboard  ( STR+V )";
			return TRUE;

		case TB_WIN2TOP:
			((LPTOOLTIPTEXT)lParam)->lpszText =
				bHEOnTop ? "set window state to non-top" : "set window state to top  ( STR+T )";
			return TRUE;

		case TB_ABOUT:
			((LPTOOLTIPTEXT)lParam)->lpszText = "about  ( F12 )";
			return TRUE;

		case TB_CLOSE:
			((LPTOOLTIPTEXT)lParam)->lpszText = "close this window  ( ESC )";
			return TRUE;
		}
	}

	return FALSE; // ERR
}