#include "ctlspriv.h"

/////////////////////////////////////////////////////////////////////////////
//
// updown.c : A micro-scrollbar control; useful for increment/decrement.
//
/////////////////////////////////////////////////////////////////////////////

#define NUM_UDACCELS 3

#define DONTCARE    0
#define SIGNED      1
#define UNSIGNED    2

#define UD_HITNOWHERE 0
#define UD_HITDOWN 1
#define UD_HITUP 2

typedef struct {
    CCONTROLINFO ci;
    HWND    hwndBuddy;
    unsigned fUp        : 1;
    unsigned fDown      : 1;
    unsigned fUnsigned  : 1;
    unsigned fSharedBorder  : 1;
    unsigned fSunkenBorder  : 1;
    unsigned fUpDownDestroyed : 1;  // This tells the buddy that updown destoryed.
    BOOL     fTrackSet: 1;
    unsigned fSubclassed:1;     // did we subclass the buddy?

    UINT     nBase;
    int      nUpper;
    int      nLower;
    int      nPos;
    UINT     uClass;
    BOOL     bDown;
    DWORD    dwStart;
    UINT     nAccel;
    UDACCEL  *udAccel;
    UINT     uHot;
    int      cReenterSetint;    // To avoid recursion death in setint()

    HTHEME   hTheme;
    HTHEME   hThemeBuddy;

} UDSTATE, *PUDSTATE;


// Constants:
//
#define CLASS_UNKNOWN   0
#define CLASS_EDIT  1
#define CLASS_LISTBOX   2

#define MAX_INTLENGTH   18 // big enough for all intl stuff, too

// this is the space to the left and right of the arrow (in pixels)
#define XBORDER 0

#define BASE_DECIMAL    10
#define BASE_HEX        16

// Declarations:
//
LRESULT CALLBACK ArrowKeyProc(HWND hWnd, UINT uMsg, WPARAM wParam,
    LPARAM lParam, UINT_PTR uIdSubclass, ULONG_PTR dwRefData);

/////////////////////////////////////////////////////////////////////////////

//
// ***** Internal workhorses *****
//


// Validates the buddy.
//
void isgoodbuddy(PUDSTATE np)
{
    if (!np->hwndBuddy)
        return;
    if (!IsWindow(np->hwndBuddy))
    {
#if defined(DEBUG) && !defined(WIN32)
        DebugOutput(DBF_ERROR | DBF_USER,
                    TEXT("UpDown: invalid buddy handle 0x04X; ")
                    TEXT("resetting to NULL"), np->hwndBuddy);
#endif
        np->hwndBuddy = NULL;
        np->uClass = CLASS_UNKNOWN;
    }
    if (GetParent(np->hwndBuddy) != np->ci.hwndParent)
    {
#if defined(DEBUG) && !defined(WIN32)
        DebugOutput(DBF_ERROR | DBF_USER,
                    TEXT("UpDown: buddy has different parent; ")
                    TEXT("resetting to NULL"));
#endif
        np->hwndBuddy = NULL;
        np->uClass = CLASS_UNKNOWN;
    }
}

// Picks a good buddy.
//
void pickbuddy(PUDSTATE np)
{
    if (np->ci.style & UDS_AUTOBUDDY)
        np->hwndBuddy = GetWindow(np->ci.hwnd, GW_HWNDPREV);
}

void unachor(PUDSTATE np)
{
    RECT rc;
    RECT rcBuddy;
    RECT rcUD;

    if ( np->hwndBuddy && (np->ci.style & (UDS_ALIGNLEFT | UDS_ALIGNRIGHT))) {
        GetWindowRect(np->hwndBuddy, &rcBuddy);
        GetWindowRect(np->ci.hwnd, &rcUD);
        UnionRect(&rc, &rcUD, &rcBuddy);
        MapWindowRect(NULL, np->ci.hwndParent, &rc);
        MoveWindow(np->hwndBuddy, rc.left, rc.top,
                                rc.right - rc.left, rc.bottom - rc.top, FALSE);

    }
}

// Anchor this control to the buddy's edge, if appropriate.
//
void anchor(PUDSTATE np)
{
    BOOL bAlignToBuddy;
    int nOver = 0,  nHasBorder;
    RECT rc, rcBuddy;
    int nHeight, nWidth;

    np->fSharedBorder = FALSE;

    isgoodbuddy(np);
    nHasBorder = (np->ci.style & WS_BORDER) == WS_BORDER;

    bAlignToBuddy = np->hwndBuddy && (np->ci.style & (UDS_ALIGNLEFT | UDS_ALIGNRIGHT));

    if (bAlignToBuddy)
    {
        if ((np->uClass == CLASS_EDIT) ||
                (GetWindowLong(np->hwndBuddy, GWL_EXSTYLE) & WS_EX_CLIENTEDGE))
        {
            np->fSunkenBorder = TRUE;
        }

        GetWindowRect(np->hwndBuddy, &rc);

        if ((np->uClass == CLASS_EDIT) || (GetWindowLong(np->hwndBuddy, GWL_STYLE) & WS_BORDER))
        {
            // FEATURE: for full generalization, should handle border AND clientedge

            nOver = g_cxBorder * (np->fSunkenBorder ? 2 : 1);
            np->fSharedBorder = TRUE;

            // turn off border styles...
            np->ci.style &= ~WS_BORDER;

            SetWindowLong(np->ci.hwnd, GWL_STYLE, np->ci.style);
            SetWindowLong(np->ci.hwnd, GWL_EXSTYLE, GetWindowLong(np->ci.hwnd, GWL_EXSTYLE) & ~(WS_EX_CLIENTEDGE));
        }
    }
    else
    {
        GetWindowRect(np->ci.hwnd, &rc);
    }

    nHeight = rc.bottom - rc.top;
    nWidth = rc.right - rc.left;

    //
    // If the parent is RTL mirrored, then placement of the
    // child (i.e. anchor point) should be relative to the visual 
    // right edge (near edge). [samera]
    //
    if (IS_WINDOW_RTL_MIRRORED(np->ci.hwndParent))
    {
        rc.left = rc.right;
    }

    ScreenToClient(np->ci.hwndParent, (LPPOINT)&rc.left);
    rc.right = rc.left + nWidth;

    if (bAlignToBuddy)
    {
        nWidth = g_cxVScroll - g_cxBorder;
        if (nWidth > nHeight) {             // don't let the aspect ratio
            nWidth = nHeight;               // get worse than square
        }
        nWidth += nOver;
        rcBuddy = rc;

        if (np->ci.style & UDS_ALIGNLEFT)
        {
            // size buddy to right
            rcBuddy.left += nWidth - nOver;
            rc.right = rc.left + nWidth;
        }
        else
        {
            // size buddy to left
            rcBuddy.right -= nWidth - nOver;
            rc.left = rc.right - nWidth;
        }
        // size the buddy to fit the updown on the appropriate side
        MoveWindow(np->hwndBuddy, rcBuddy.left, rcBuddy.top,
                                rcBuddy.right - rcBuddy.left, nHeight, TRUE);
    }
    else if (!(np->ci.style & UDS_HORZ))
    {
        nWidth = g_cxVScroll + 2 * nHasBorder;
    }

    SetWindowPos(np->ci.hwnd, NULL, rc.left, rc.top, nWidth, nHeight,
        SWP_DRAWFRAME | SWP_NOZORDER | SWP_NOACTIVATE);
}


// Use this to make any and all comparisons involving the nPos,
// nUpper or nLower fields of the PUDSTATE. It determines
// whether to do a signed or unsigned comparison and returns
//  > 0 for (x > y)
//  < 0 for (x < y)
// == 0 for (x == y).
//
// fCompareType is SIGNED to force a signed comparison,
// fCompareType is UNSIGNED to force an unsigned comparison,
// fCompareType is DONTCARE to use the np->fUnsigned flag to decide.
//
// In comments, comparison operators are suffixed with "D", "U" or "S"
// to emphasize whether the comparison is DONTCARE, UNSIGNED, or SIGNED.
// For example "x <U y" means "x < y as UNSIGNED".

int compare(PUDSTATE np, int x, int y, UINT fCompareType)
{
    if ((fCompareType == UNSIGNED) || ((np->fUnsigned) && !(fCompareType == SIGNED)) )
    {
        // Do unsigned comparisons
        if ((UINT)x > (UINT)y)
            return 1;
        else if ((UINT)x < (UINT)y)
            return -1;
    }
    else
    {
        // Do signed comparisons
        if (x > y)
            return 1;
        else if (x < y)
            return -1;
    }

    return 0;
}

// Use this after any pos change to make sure pos stays in range.
// Wraps as necessary.
// returns nonzero if the current value was out of range (and therefore
// got changed so it fit into range again)
//

BOOL nudge(PUDSTATE np)
{
    BOOL bOutOfRange = TRUE;
    int min = np->nUpper;
    int max = np->nLower;

    // if (max <D min) swap(min, max)
    if (compare(np,max,min, DONTCARE) < 0)
    {
        int t;
        t = min;
        min = max;
        max = t;
    }


    if (np->ci.style & UDS_WRAP)
    {
        // if (nPos <D min) nPos = max      -- wrap from below to above
        // else if (nPos >D max) nPos = min -- wrap from above to below

        if ((compare(np, np->nPos, min, DONTCARE) < 0))
            np->nPos = max;
        else if ((compare(np, np->nPos, max, DONTCARE) > 0))
            np->nPos = min;
        else bOutOfRange = FALSE;
    }
    else
    {
        // if (nPos <D min) nPos = min      -- pin at min
        // else if (nPos >D max) nPos = max -- pin at max

        if (compare(np,np->nPos,min, DONTCARE) < 0)
            np->nPos = min;
        else if (compare(np,np->nPos,max, DONTCARE) > 0)
            np->nPos = max;
        else
            bOutOfRange = FALSE;
    }

    return(bOutOfRange);
}

// Sets the state of the buttons (pushed, released).
//
void squish(PUDSTATE np, UINT bTop, UINT bBottom)
{
    BOOL bInvalidate = FALSE;

    if (np->nUpper == np->nLower || !IsWindowEnabled(np->ci.hwnd))
    {
        bTop = FALSE;
        bBottom = FALSE;
    }
    else
    {
        bTop = !!bTop;
        bBottom = !!bBottom;
    }

    if (np->fUp != bTop)
    {
        np->fUp = bTop;
        bInvalidate = TRUE;

        NotifyWinEvent(EVENT_OBJECT_STATECHANGE, np->ci.hwnd, OBJID_CLIENT, 1);
    }

    if (np->fDown != bBottom)
    {
        np->fDown = bBottom;
        bInvalidate = TRUE;

        NotifyWinEvent(EVENT_OBJECT_STATECHANGE, np->ci.hwnd, OBJID_CLIENT, 2);
    }

    if (bInvalidate)
    {
        np->dwStart = GetTickCount();
        InvalidateRect(np->ci.hwnd, NULL, FALSE);
    }
}

// Gets the intl 1000 separator
//
void getthousands(LPTSTR pszThousand)
{
#ifdef WIN32
    if (!GetLocaleInfo(LOCALE_USER_DEFAULT, LOCALE_STHOUSAND, pszThousand, 2))
    {
        pszThousand[0] = TEXT(',');
        pszThousand[1] = TEXT('\0');
    }
#else
    static DWORD uLast = 0;
    static TCHAR cThou;
    DWORD uNow;

    /* Only check the intl setting every 5 seconds.
     */
    uNow = GetTickCount();
    if (uNow - uLast > 5000)
    {
        if (!GetProfileString(TEXT("intl"), TEXT("sThousand"), pszThousand, pszThousand, 2))
        {
            pszThousand[0] = TEXT(',');
            pszThousand[1] = TEXT('\0');
        }
        cThou = pszThousand[0];
        uLast = uNow;
    }
    else
    {
        pszThousand[0] = cThou;
        pszThousand[1] = 0;
    }

#endif
}

//
//  Obtain NLS info about how numbers should be grouped.
//
//  The annoying thing is that LOCALE_SGROUPING and NUMBERFORMAT
//  have different ways of specifying number grouping.
//
//          LOCALE      NUMBERFMT      Sample   Country
//
//          3;0         3           1,234,567   United States
//          3;2;0       32          12,34,567   India
//          3           30           1234,567   ??
//
//  Not my idea.  That's the way it works.
//
//  Bonus treat - Win9x doesn't support complex number formats,
//  so we return only the first number.
//
UINT getgrouping(void)
{
    UINT grouping;
    LPTSTR psz;
    TCHAR szGrouping[32];

    // If no locale info, then assume Western style thousands
    if (!GetLocaleInfo(LOCALE_USER_DEFAULT, LOCALE_SGROUPING, szGrouping, ARRAYSIZE(szGrouping)))
        return 3;

    grouping = 0;
    psz = szGrouping;
    for (;;)
    {
        if (*psz == '0') break;             // zero - stop

        else if ((UINT)(*psz - '0') < 10)   // digit - accumulate it
            grouping = grouping * 10 + (UINT)(*psz - '0');

        else if (*psz)                      // punctuation - ignore it
            { }

        else                                // end of string, no "0" found
        {
            grouping = grouping * 10;       // put zero on end (see examples)
            break;                          // and finished
        }

        psz++;
    }

    return grouping;
}

// Gets the caption of the buddy
// Returns the current position of the updown control
// and sets *pfError on error.
//
LRESULT getint(PUDSTATE np, BOOL *pfError)
{
    TCHAR szInt[MAX_INTLENGTH]; // big enough for all intl stuff, too
    TCHAR szThousand[2];
    TCHAR cTemp;
    int nPos;
    int sign = 1;
    LPTSTR p = szInt;
    BOOL bInValid = TRUE;

    isgoodbuddy(np);
    if (np->hwndBuddy && np->ci.style & UDS_SETBUDDYINT)
    {
        if (np->uClass == CLASS_LISTBOX)
        {
            np->nPos = (int)SendMessage(np->hwndBuddy, LB_GETCURSEL, 0, 0L);
            bInValid = nudge(np);
        }
        else
        {
            GetWindowText(np->hwndBuddy, szInt, ARRAYSIZE(szInt));

            switch (np->nBase)
            {
                case BASE_HEX:
                    if ((*p == TEXT('x')) || (*p == TEXT('X')))
                        // ignore first character
                        p++;
                    else if ((*p == TEXT('0')) && ((*(p + 1) == TEXT('x')) || (*(p + 1) == TEXT('X'))))
                        // ignore first two characters (TEXT("0x") or "0X")
                        p += 2;

                    for (nPos = 0; *p; p++)
                    {
                        if ((*p >= TEXT('A')) && (*p <= TEXT('F')))
                            cTemp = (TCHAR)(*p - TEXT('A') + 10);
                        else if ((*p >= TEXT('a')) && (*p <= TEXT('f')))
                            cTemp = (TCHAR)(*p - TEXT('a') + 10);
                        else if ((*p >= TEXT('0')) && (*p <= TEXT('9')))
                            cTemp = (TCHAR)(*p - TEXT('0'));
                        else
                            goto BadValue;

                        nPos = (nPos * 16) + cTemp;
                    }
                    np->nPos = nPos;
                    break;

                case BASE_DECIMAL:
        default:
                    getthousands(szThousand);
                    if (*p == TEXT('-') && !np->fUnsigned)
                    {
                        sign = -1;
                        ++p;
                    }

                    for (nPos=0; *p; p++)
                    {
                        cTemp = *p;

                        // If there is a thousand separator, just ignore it.
                        // Do not validate that it's in the right place,
                        // because it prevents the user from editing the
                        // middle of a number.
                        if (cTemp == szThousand[0])
                        {
                            continue;
                        }

                        cTemp -= TEXT('0');
                        if ((UINT)cTemp > 9)
                        {
                            goto BadValue;
                        }
                        nPos = (nPos*10) + cTemp;
                    }

                    np->nPos = nPos*sign;
                    break;
            }
            bInValid = nudge(np);
        }
    }

BadValue:
    if (pfError)
        *pfError = bInValid;
    return np->nPos;
}

// Sets the caption of the buddy if appropriate.
//
void setint(PUDSTATE np)
{
    TCHAR szInt[MAX_INTLENGTH];
    TCHAR szThousand[2];
    int pos = np->nPos;
    LPTSTR p = szInt;

    isgoodbuddy(np);
    if (np->hwndBuddy && np->ci.style & UDS_SETBUDDYINT)
    {
        BOOL fError;
        /*
         * If we have reentered, then maybe the app has set up a loop.
         * Check to see if the value has actually changed.  If not,
         * then there's no need to set it again.  This breaks the
         * recursion.
         */
        if (np->cReenterSetint && (LRESULT)pos==getint(np, &fError) && !fError)
        {
            return;
        }
        np->nPos = pos;

        np->cReenterSetint++;

        if (np->uClass == CLASS_LISTBOX)
        {
            SendMessage(np->hwndBuddy, LB_SETCURSEL, pos, 0L);
            FORWARD_WM_COMMAND(GetParent(np->hwndBuddy),
                                GetDlgCtrlID(np->hwndBuddy),
                np->hwndBuddy, LBN_SELCHANGE, SendMessage);
        }
        else
        {
            switch (np->nBase)
            {
                case BASE_HEX:

                    if ((np->nUpper | np->nLower) >= 0x00010000)
                        wsprintf(p, TEXT("0x%08X"), pos);
                    else
                        wsprintf(p, TEXT("0x%04X"), pos);
                    break;

                case BASE_DECIMAL:
        default:
                    if (pos < 0 && !np->fUnsigned)
                    {
                        *p++ = TEXT('-');
                        pos = -pos;
                    }

                    if (pos >= 1000 && !(np->ci.style & UDS_NOTHOUSANDS))
                    {
                        TCHAR szFmt[MAX_INTLENGTH];
                        NUMBERFMT nf;
                        nf.NumDigits = 0;   // no digits after decimal point
                        nf.LeadingZero = 0; // no leading zeros
                        nf.Grouping = getgrouping();
                        nf.lpDecimalSep = TEXT(""); // no decimal point
                        nf.lpThousandSep = szThousand;
                        nf.NegativeOrder = 0; // (not used - we always pass positive numbers)
                        getthousands(szThousand);
                        wsprintf(szFmt, TEXT("%u"), pos);
                        GetNumberFormat(LOCALE_USER_DEFAULT, 0, szFmt, &nf, p, MAX_INTLENGTH - 1);
                    }
                    else
                    {
                        wsprintf(p, TEXT("%u"), pos);
                    }
                    break;
            }

            SetWindowText(np->hwndBuddy, szInt);
        }

        np->cReenterSetint;
    }
}

// Use this to click the pos up or down by one.
//
void bump(PUDSTATE np)
{
    BOOL bChanged = FALSE;
    UINT uElapsed, increment;
    int direction, i;

    /* So I'm not really getting seconds here; it's close enough, and
     * dividing by 1024 keeps __aFuldiv from being needed.
     */
    uElapsed = (UINT)((GetTickCount() - np->dwStart) / 1024);

    if (np->udAccel != NULL)
    {
        increment = np->udAccel[0].nInc;
        for (i=np->nAccel-1; i>=0; --i)
        {
            if (np->udAccel[i].nSec <= uElapsed)
            {
                increment = np->udAccel[i].nInc;
                break;
            }
        }
    }
    else
    {
        increment = 1;
    }

    if (increment == 0)
    {
        DebugMsg(DM_ERROR, TEXT("bad accelerator value"));
        return;
    }

    direction = compare(np,np->nUpper,np->nLower, DONTCARE) < 0 ? -1 : 1;
    if (np->fUp)
    {
        bChanged = TRUE;
    }
    if (np->fDown)
    {
        direction = -direction;
        bChanged = TRUE;
    }

    if (bChanged)
    {
        /* Make sure we have a multiple of the increment
         * Note that we should loop only when the increment changes
         */
        NM_UPDOWN nm;

        nm.iPos = np->nPos;
        nm.iDelta = increment*direction;
        if (CCSendNotify(&np->ci, UDN_DELTAPOS, &nm.hdr))
            return;

        np->nPos += nm.iDelta;
        for ( ; ; )
        {
            if (!((int)np->nPos % (int)increment))
            {
                break;
            }
            np->nPos += direction;
        }

        nudge(np);
        setint(np);
        if (np->ci.style & UDS_HORZ)
            FORWARD_WM_HSCROLL(np->ci.hwndParent, np->ci.hwnd, SB_THUMBPOSITION, np->nPos, SendMessage);
        else
            FORWARD_WM_VSCROLL(np->ci.hwndParent, np->ci.hwnd, SB_THUMBPOSITION, np->nPos, SendMessage);

        NotifyWinEvent(EVENT_OBJECT_VALUECHANGE, np->ci.hwnd, OBJID_CLIENT, 0);
    }
}

//#pragma data_seg(DATASEG_READONLY)
const TCHAR c_szListbox[] = TEXT("listbox");
//#pragma data_seg()

// Sets the new buddy
//
LRESULT setbuddy(PUDSTATE np, HWND hwndBuddy)
{
    HWND hOldBuddy;
    TCHAR szClName[10];

    hOldBuddy = np->hwndBuddy;

    if (np->hThemeBuddy)
    {
        CloseThemeData(np->hThemeBuddy);
        np->hThemeBuddy = NULL;
    }

    if ((np->hwndBuddy = hwndBuddy) == NULL)
    {
        pickbuddy(np);
        hwndBuddy = np->hwndBuddy;
    }

    if ((hOldBuddy != hwndBuddy) && np->fSubclassed)
    {
        ASSERT(hOldBuddy);
        RemoveWindowSubclass(hOldBuddy, ArrowKeyProc, 0);
        np->fSubclassed = FALSE;
    }

    np->uClass = CLASS_UNKNOWN;
    if (hwndBuddy)
    {
        if (np->ci.style & UDS_ARROWKEYS)
        {
            np->fSubclassed = TRUE;
            SetWindowSubclass(hwndBuddy, ArrowKeyProc, 0, (ULONG_PTR)np);
        }

        GetClassName(hwndBuddy, szClName, ARRAYSIZE(szClName));
        if (!lstrcmpi(szClName, c_szEdit))
        {
            np->uClass = CLASS_EDIT;
            np->hThemeBuddy = OpenThemeData(hwndBuddy, WC_EDIT);
        }
        else if (!lstrcmpi(szClName, c_szListbox))
        {
            np->uClass = CLASS_LISTBOX;
        }
    }

    anchor(np);
    return (LRESULT)hOldBuddy;
}


//
// This is how CCThemeDrawEdge should be implemented once DrawThemeLine supports part and 
// state ids
//
//
BOOL UpDown_ThemeDrawEdge(HTHEME hTheme, HDC hdc, PRECT prc, int iPartId, int iStateId, UINT uFlags)
{
    BOOL  fRet = FALSE;
    RECT  rc;
    int   cxBorder, cyBorder;

    if (SUCCEEDED(GetThemeInt(hTheme, iPartId, iStateId, TMT_SIZINGBORDERWIDTH, &cxBorder)))
    {
        cyBorder = cxBorder;
    }
    else
    {
        cxBorder = g_cxBorder;
        cyBorder = g_cyBorder;
    }

    rc = *prc;

    if (uFlags & BF_LEFT)
    {
        rc.left += cxBorder;
    }

    if (uFlags & BF_TOP)
    {
        rc.top += cyBorder;
    }

    if (uFlags & BF_RIGHT)
    {
        rc.right -= cxBorder;
    }

    if (uFlags & BF_BOTTOM)
    {
        rc.bottom -= cyBorder;
    }

    ExcludeClipRect(hdc, rc.left, rc.top, rc.right, rc.bottom);

    if (SUCCEEDED(DrawThemeBackground(hTheme, hdc, iPartId, iStateId, prc, 0)))
    {
        fRet = TRUE;

        if (uFlags & BF_ADJUST)
        {
            *prc = rc;
        }
    }

    SelectClipRgn(hdc, NULL);

    return fRet;
}

// Paint the whole control
//

// PaintUpDownControl is theme aware
void PaintUpDownControl(PUDSTATE np, HDC hdc)
{
    UINT uFlags;
    PAINTSTRUCT ps;
    RECT rcBtn;
    RECT rc;

    int iPartId;
    int iStateId;

    BOOL bEnabled = (np->nUpper != np->nLower) && IsWindowEnabled(np->ci.hwnd);

    if (np->hwndBuddy)
        bEnabled = bEnabled && IsWindowEnabled(np->hwndBuddy);

    if (hdc)
        ps.hdc = hdc;
    else
        BeginPaint(np->ci.hwnd, &ps);

    GetClientRect(np->ci.hwnd, &rcBtn);

    // if we are autobuddy'd and anchored to a sunken-edge control, we draw the
    // "nonclient" area of ourselves to blend in with our buddy.
    if (!np->hTheme || (np->hThemeBuddy && (np->uClass == CLASS_EDIT)))
    {
        if (np->fSharedBorder && np->fSunkenBorder)
        {
            UINT bf = BF_TOP | BF_BOTTOM | BF_ADJUST |
                      (np->ci.style & UDS_ALIGNLEFT ? BF_LEFT : 0) |
                      (np->ci.style & UDS_ALIGNRIGHT ? BF_RIGHT : 0);

            if (!np->hThemeBuddy)
            {
                DrawEdge(ps.hdc, &rcBtn, EDGE_SUNKEN, bf);
            }
            else
            {
                UpDown_ThemeDrawEdge(np->hThemeBuddy, 
                                     ps.hdc, 
                                     &rcBtn, 
                                     EP_EDITTEXT, 
                                     bEnabled ? ETS_NORMAL : ETS_DISABLED, 
                                     bf);

            }
        }
    }

    // with remaining space, draw appropriate scrollbar arrow controls in
    // upper and lower halves

    rc = rcBtn;
    if (np->ci.style & UDS_HORZ)
    {
        iPartId = SPNP_DOWNHORZ;  // Down horizontal
        iStateId = DNHZS_NORMAL;

        uFlags = DFCS_SCROLLLEFT;
        if (np->fDown)
        {
            uFlags |= DFCS_PUSHED;

            iStateId = DNHZS_PRESSED;
        }

        if (!bEnabled)
        {
            uFlags |= DFCS_INACTIVE;

            iStateId = DNHZS_DISABLED;
        }
            
        if (np->uHot == UD_HITDOWN)
        {
            uFlags |= DFCS_HOT;

            if (iStateId == DNHZS_NORMAL)
                iStateId = DNHZS_HOT;
        }
        
        // Horizontal ones
        rc.right = (rcBtn.right + rcBtn.left) / 2;

        if (np->hTheme)
        {
            DrawThemeBackground(np->hTheme, ps.hdc, iPartId, iStateId, &rc, 0);
        }
        else
        {
            DrawFrameControl(ps.hdc, &rc, DFC_SCROLL,
                             uFlags);
        }

        iPartId = SPNP_UPHORZ;  // Up horizontal
        iStateId = UPHZS_NORMAL;

        uFlags = DFCS_SCROLLRIGHT;
        if (np->fUp)
        {
            uFlags |= DFCS_PUSHED;

            iStateId = UPHZS_PRESSED;
        }

        if (!bEnabled)
        {
            uFlags |= DFCS_INACTIVE;

            iStateId = UPHZS_DISABLED;
        }
            
        if (np->uHot == UD_HITUP)
        {
            uFlags |= DFCS_HOT;

            if (iStateId == UPHZS_NORMAL)
                iStateId = UPHZS_HOT;
        }

        rc.left = rcBtn.right - (rc.right - rc.left); // handles odd-x case, too
        rc.right = rcBtn.right;

        if (np->hTheme)
        {
            DrawThemeBackground(np->hTheme, ps.hdc, iPartId, iStateId, &rc, 0);
        }
        else
        {
            DrawFrameControl(ps.hdc, &rc, DFC_SCROLL, uFlags);
        }
    }
    else
    {
        iPartId = SPNP_UP;  // Up vertical
        iStateId = UPS_NORMAL;

        uFlags = DFCS_SCROLLUP;
        if (np->fUp)
        {
            uFlags |= DFCS_PUSHED;

            iStateId = UPS_PRESSED;
        }

        if (!bEnabled)
        {
            uFlags |= DFCS_INACTIVE;

            iStateId = UPS_DISABLED;
        }
            
        if (np->uHot == UD_HITUP)
        {
            uFlags |= DFCS_HOT;

            if (iStateId == UPS_NORMAL)
                iStateId = UPS_HOT;
        }

        rc.bottom = (rcBtn.bottom + rcBtn.top) / 2;

        if (np->hTheme)
        {
            DrawThemeBackground(np->hTheme, ps.hdc, iPartId, iStateId, &rc, 0);
        }
        else
        {
            DrawFrameControl(ps.hdc, &rc, DFC_SCROLL, uFlags);
        }

        iPartId = SPNP_DOWN;  // Down vertical
        iStateId = DNS_NORMAL;

        uFlags = DFCS_SCROLLDOWN;
        if (np->fDown)
        {
            uFlags |= DFCS_PUSHED;

            iStateId = DNS_PRESSED;
        }

        if (!bEnabled)
        {
            uFlags |= DFCS_INACTIVE;

            iStateId = DNS_DISABLED;
        }
            
        if (np->uHot == UD_HITDOWN)
        {
            uFlags |= DFCS_HOT;

            if (iStateId == DNS_NORMAL)
                iStateId = DNS_HOT;
        }

        rc.top = rcBtn.bottom - (rc.bottom - rc.top); // handles odd-y case, too
        rc.bottom = rcBtn.bottom;

        if (np->hTheme)
        {
            DrawThemeBackground(np->hTheme, ps.hdc, iPartId, iStateId, &rc, 0);
        }
        else
        {
            DrawFrameControl(ps.hdc, &rc, DFC_SCROLL,
                             uFlags);
        }
    }

    if (hdc == NULL)
        EndPaint(np->ci.hwnd, &ps);
}


LRESULT CALLBACK ArrowKeyProc(HWND hWnd, UINT uMsg, WPARAM wParam,
    LPARAM lParam, UINT_PTR uIdSubclass, ULONG_PTR dwRefData)
{
    PUDSTATE    np = (PUDSTATE)dwRefData;
    int         cDetants;
    HRGN        hrgnEdit = NULL;
    LRESULT     lResult;

    switch (uMsg)
    {
    case WM_NCDESTROY:
        RemoveWindowSubclass(hWnd, ArrowKeyProc, 0);
        np->fSubclassed = FALSE;
        np->hwndBuddy = NULL;
        if (np->fUpDownDestroyed)
        {
            // The buddy was destroyed after updown so free the memory now
            // And pass off to the message to who we subclassed...
            LocalFree((HLOCAL)np);
        }
        break;

    case WM_GETDLGCODE:
        return (DefSubclassProc(hWnd, uMsg, wParam, lParam) | DLGC_WANTARROWS);

    case WM_KEYDOWN:
        switch (wParam)
        {
        case VK_UP:
        case VK_DOWN:
            if (GetCapture() != np->ci.hwnd)
            {
                /* Get the value from the buddy if this is the first key down
                 */
                if (!(lParam&(1L<<30)))
                {
                    getint(np, NULL);
                }

                /* Update the visuals and bump the value
                 */
                np->bDown = (wParam == VK_DOWN);
                squish(np, !np->bDown, np->bDown);
                bump(np);

                //notify of navigation key usage
                CCNotifyNavigationKeyUsage(&(np->ci), UISF_HIDEFOCUS);
            }
            return(0L);

        default:
            break;
        }
        break;

    case WM_KEYUP:
        switch (wParam)
        {
        case VK_UP:
        case VK_DOWN:
            if (GetCapture() != np->ci.hwnd)
            {
                squish(np, FALSE, FALSE);
            }
            return(0L);

        default:
            break;
        }
        break;

        // this is dumb.
        // wm_char's aren't sent for arrow commands..
        // what you're really eating here is & and (.
#if 0
    case WM_CHAR:
        switch (wParam)
        {
        case VK_UP:
        case VK_DOWN:
            return(0L);

        default:
            break;
        }
        break;
#endif

    case WM_KILLFOCUS:
        // Reset wheel scroll amount
        gcWheelDelta = 0;
        break;

    case WM_NCPAINT:
        if (np->hTheme && (np->uClass == CLASS_EDIT))
        {
            RECT rc;
            HRGN hrgnSpin;
            
            //
            // exclude the updown window rect from the edit painting region
            //

            GetWindowRect(np->ci.hwnd, &rc);
            hrgnSpin = CreateRectRgn(rc.left, rc.top, rc.right, rc.bottom);

            if (hrgnSpin)
            {
                switch (wParam)
                {
                case 0:
                case 1:
                    //
                    // update the entire edit nc area
                    //
                    GetWindowRect(hWnd, &rc);
                    hrgnEdit = CreateRectRgn(rc.left, rc.top, rc.right, rc.bottom);

                    if (!hrgnEdit)
                    {
                        break;
                    }

                    wParam = (WPARAM)hrgnEdit;

                    // fall through

                default:

                    //
                    // exclude spin rgn from edit rgn
                    //
                    CombineRgn((HRGN)wParam, (HRGN)wParam, hrgnSpin, RGN_DIFF);
                }

                DeleteObject(hrgnSpin);
            }
        }
        break;

    default:
        if ((uMsg == g_msgMSWheel) && (GetCapture() != np->ci.hwnd)) 
        {

            int iWheelDelta = GET_WHEEL_DELTA_WPARAM(wParam);
            // Update count of scroll amount
            gcWheelDelta -= iWheelDelta;
            cDetants = gcWheelDelta / WHEEL_DELTA;

            if (cDetants != 0)
            {
                gcWheelDelta %= WHEEL_DELTA;

                if (GET_KEYSTATE_WPARAM(wParam) & (MK_SHIFT | MK_CONTROL))
                {
                    break;
                }

                getint(np, NULL);
                np->bDown = (cDetants > 0);
                cDetants = abs(cDetants);
                while (cDetants-- > 0) 
                {
                    squish(np, !np->bDown, np->bDown);
                    bump(np);
                }
                squish(np, FALSE, FALSE);
            }

            return 1;
        }

        break;
    }

    lResult = DefSubclassProc(hWnd, uMsg, wParam, lParam);

    if (hrgnEdit)
    {
        DeleteObject(hrgnEdit);
    }

    return lResult;
}

UINT setbase(PUDSTATE np, UINT wNewBase)
{
    UINT wOldBase;

    switch (wNewBase)
    {
        case BASE_DECIMAL:
        case BASE_HEX:
            np->fUnsigned = (wNewBase != BASE_DECIMAL);
            wOldBase = np->nBase;
            np->nBase = wNewBase;
            setint(np);
            return wOldBase;
    }

    return 0;
}

/////////////////////////////////////////////////////////////////////////////

HWND WINAPI CreateUpDownControl(DWORD dwStyle, int x, int y, int cx, int cy,
                                HWND hParent, int nID, HINSTANCE hInst,
                                HWND hwndBuddy, int nUpper, int nLower, int nPos)
{
    HWND hWnd = CreateWindow(s_szUpdownClass, NULL, dwStyle, x, y, cx, cy,
                             hParent, IntToPtr_(HMENU, nID), hInst, 0L);
    if (hWnd)
    {
        SendMessage(hWnd, UDM_SETBUDDY, (WPARAM)hwndBuddy, 0L);
        SendMessage(hWnd, UDM_SETRANGE, 0, MAKELONG(nUpper, nLower));
        SendMessage(hWnd, UDM_SETPOS, 0, MAKELONG(nPos, 0));
    }
    return hWnd;
}

UINT UD_HitTest(PUDSTATE np, int x, int y)
{
    RECT rc;

    GetClientRect(np->ci.hwnd, &rc);
    if (np->ci.style & UDS_HORZ)
    {
        // Horizontal placement
        if (x < (rc.right / 2))
        {
            return UD_HITDOWN;
        }
        else if (x > (rc.right / 2))
        {
            return UD_HITUP;
        }
    }
    else
    {
        if (y > (rc.bottom / 2))
        {
            return UD_HITDOWN;
        }
        else if (y < (rc.bottom / 2))
        {
            return UD_HITUP;
        }
    }

    return UD_HITNOWHERE;
}

void UD_Invalidate(PUDSTATE np, UINT uWhich, BOOL fErase)
{
    int iMid;
    RECT rc;

    GetClientRect(np->ci.hwnd, &rc);
    if (np->ci.style & UDS_HORZ)
    {
        iMid = rc.right / 2;
        if (uWhich == UD_HITDOWN) {
            rc.right = iMid;
        } else if (uWhich == UD_HITUP) {
            rc.left = iMid;
        } else
            return;
    }
    else
    {
        iMid = rc.bottom /2;
        if (uWhich == UD_HITDOWN) {
            rc.top = iMid;
        } else if (uWhich == UD_HITUP){
            rc.bottom = iMid;
        } else
            return;
    }

    InvalidateRect(np->ci.hwnd, &rc, fErase);
}

void UD_OnMouseMove(PUDSTATE np, DWORD dwPos)
{
    if (np->ci.style & UDS_HOTTRACK) {

        UINT uHot = UD_HitTest(np, GET_X_LPARAM(dwPos), GET_Y_LPARAM(dwPos));

        if (uHot != np->uHot) {
            UD_Invalidate(np, np->uHot, FALSE);
            UD_Invalidate(np, uHot, FALSE);
            np->uHot = uHot;
        }
    }
}

/////////////////////////////////////////////////////////////////////////////

// UpDownWndProc:
//

// UpDownWndProc is theme aware
LRESULT CALLBACK UpDownWndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    RECT rc;
    int i;
    BOOL f;
    LRESULT lres;
    PUDSTATE np = GetWindowPtr(hwnd, 0);

    if (np) {
        if ((uMsg >= WM_MOUSEFIRST) && (uMsg <= WM_MOUSELAST) &&
            (np->ci.style & UDS_HOTTRACK) && !np->fTrackSet) {

            TRACKMOUSEEVENT tme;

            np->fTrackSet = TRUE;

            tme.cbSize = sizeof(tme);
            tme.hwndTrack = np->ci.hwnd;
            tme.dwFlags = TME_LEAVE;

            TrackMouseEvent(&tme);
        }
        else if (uMsg == WM_THEMECHANGED)  // Check for theme changes
        {
            if (np->hTheme)
                CloseThemeData(np->hTheme);

            np->hTheme = OpenThemeData(np->ci.hwnd, L"Spin");

            if (np->hTheme)
            {
                // Ensure style is applied
                np->ci.style |= UDS_HOTTRACK;
            }

            if (np->hThemeBuddy)
            {
                CloseThemeData(np->hThemeBuddy);
                np->hThemeBuddy = NULL;
            }

            if (np->hwndBuddy && (np->uClass == CLASS_EDIT))
            {
                np->hThemeBuddy = OpenThemeData(np->hwndBuddy, WC_EDIT);
            }

            InvalidateRect(np->ci.hwnd, NULL, TRUE);
        }

    } else if (uMsg != WM_CREATE)
        goto DoDefault;

    switch (uMsg)
    {

    case WM_MOUSEMOVE:
        UD_OnMouseMove(np, (DWORD) lParam);
        break;

    case WM_MOUSELEAVE:
        np->fTrackSet = FALSE;
        UD_Invalidate(np, np->uHot, FALSE);
        np->uHot = UD_HITNOWHERE;
        break;

    case WM_LBUTTONDOWN:
    {
        // Don't set a timer if on the middle border
        BOOL bTimeIt = TRUE;

        if (np->hwndBuddy && !IsWindowEnabled(np->hwndBuddy))
            break;

        SetCapture(hwnd);
        getint(np, NULL);

        switch (np->uClass)
        {
        case CLASS_EDIT:
        case CLASS_LISTBOX:
            SetFocus(np->hwndBuddy);
            break;
        }

        switch(UD_HitTest(np, GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam))) {
        case UD_HITDOWN:
            np->bDown = TRUE;
            squish(np, FALSE, TRUE);
            break;

        case UD_HITUP:
            np->bDown = FALSE;
            squish(np, TRUE, FALSE);
            break;

        case UD_HITNOWHERE:
            bTimeIt = FALSE;
            break;
        }

        if (bTimeIt)
        {
            SetTimer(hwnd, 1, GetProfileInt(TEXT("windows"), TEXT("CursorBlinkRate"), 530), NULL);
            bump(np);
        }
        break;
    }

    case WM_TIMER:
    {
        POINT pt;

        if (GetCapture() != hwnd)
        {
            goto EndScroll;
        }

        SetTimer(hwnd, 1, 100, NULL);

        GetWindowRect(hwnd, &rc);
        if (np->ci.style & UDS_HORZ) {
            i = (rc.left + rc.right) / 2;
            if (np->bDown)
            {
                rc.right = i;
            }
            else
            {
                rc.left = i;
            }
        } else {
            i = (rc.top + rc.bottom) / 2;
            if (np->bDown)
            {
                rc.top = i;
            }
            else
            {
                rc.bottom = i;
            }
        }
        InflateRect(&rc, (g_cxFrame+1)/2, (g_cyFrame+1)/2);
        GetCursorPos(&pt);
        if (PtInRect(&rc, pt))
        {
            squish(np, !np->bDown, np->bDown);
            bump(np);
        }
        else
        {
            squish(np, FALSE, FALSE);
        }
        break;
    }

    case WM_LBUTTONUP:
        if (np->hwndBuddy && !IsWindowEnabled(np->hwndBuddy))
            break;

        if (GetCapture() == hwnd)
        {
EndScroll:
            squish(np, FALSE, FALSE);
            // We cannot call CCReleaseCapture() here, because it busts a lot of apps.
            ReleaseCapture();
            KillTimer(hwnd, 1);

            if (np->uClass == CLASS_EDIT)
                Edit_SetSel(np->hwndBuddy, 0, -1);

                        if (np->ci.style & UDS_HORZ)
                            FORWARD_WM_HSCROLL(np->ci.hwndParent, np->ci.hwnd,
                                      SB_ENDSCROLL, np->nPos, SendMessage);
                        else
                            FORWARD_WM_VSCROLL(np->ci.hwndParent, np->ci.hwnd,
                                      SB_ENDSCROLL, np->nPos, SendMessage);
        }
        break;

    case WM_ENABLE:
        InvalidateRect(hwnd, NULL, TRUE);
        break;

    case WM_WININICHANGE:
        if (np && (!wParam ||
            (wParam == SPI_SETNONCLIENTMETRICS) ||
            (wParam == SPI_SETICONTITLELOGFONT))) {
            InitGlobalMetrics(wParam);
            unachor(np);
            anchor(np);
        }
        break;

    case WM_PRINTCLIENT:
    case WM_PAINT:
        PaintUpDownControl(np, (HDC)wParam);
        break;

    case WM_UPDATEUISTATE:
        //not sure need to set bit, will probably not use it, on the other hand this
        //  is consistent with remaining of common controls and not very expensive
        CCOnUIState(&(np->ci), WM_UPDATEUISTATE, wParam, lParam);

        goto DoDefault;

    case UDM_SETRANGE:
        np->nUpper = GET_X_LPARAM(lParam);
        np->nLower = GET_Y_LPARAM(lParam);
        nudge(np);
        break;
        
    case UDM_SETRANGE32:
        np->nUpper = (int)lParam;
        np->nLower = (int)wParam;
        break;
        
    case UDM_GETRANGE32:
        if (lParam) {
            *((LPINT)lParam) = np->nUpper;
        }
        if (wParam) {
            *((LPINT)wParam) = np->nLower;
        }
        break;
        
    case UDM_GETRANGE:
        return MAKELONG(np->nUpper, np->nLower);

    case UDM_SETBASE:
        // wParam: new base
        // lParam: not used
        // return: 0 if invalid base is specified,
        //         previous base otherwise
        return (LRESULT)setbase(np, (UINT)wParam);

    case UDM_GETBASE:
        return np->nBase;

    case UDM_SETPOS:
        lParam = GET_X_LPARAM(lParam);
        // FALL THROUGH

    case UDM_SETPOS32:
    {
        int iNewPos = (int)lParam;
        if (compare(np, np->nLower, np->nUpper, DONTCARE) < 0) {

            if (compare(np, iNewPos, np->nUpper, DONTCARE) > 0) {
                iNewPos = np->nUpper;
            }

            if (compare(np, iNewPos, np->nLower, DONTCARE) < 0) {
                iNewPos = np->nLower;
            }
        } else {
            if (compare(np, iNewPos, np->nUpper, DONTCARE) < 0) {
                iNewPos = np->nUpper;
            }

            if (compare(np, iNewPos, np->nLower, DONTCARE) > 0) {
                iNewPos = np->nLower;
            }
        }

        i = np->nPos;
        np->nPos = iNewPos;
        setint(np);
        NotifyWinEvent(EVENT_OBJECT_VALUECHANGE, np->ci.hwnd, OBJID_CLIENT, 0);
        return (LRESULT)i;
    }

    case UDM_GETPOS:
        lres = getint(np, &f);
        return MAKELRESULT(lres, f);

    case UDM_GETPOS32:
        return getint(np, (BOOL *)lParam);

    case UDM_SETBUDDY:
        return setbuddy(np, (HWND)wParam);

    case UDM_GETBUDDY:
        return (LRESULT)np->hwndBuddy;

    case UDM_SETACCEL:
        if (wParam == 0)
        {
            return FALSE;
        }

        if (wParam >= NUM_UDACCELS)
        {
            UDACCEL *puda;
            puda = (UDACCEL *)LocalReAlloc((HLOCAL)np->udAccel, sizeof(UDACCEL)*wParam, LMEM_MOVEABLE);
            if (!puda)
            {
                return FALSE;
            }
            else
            {
                np->udAccel = puda;
            }
        }

        if (np->udAccel != NULL)
        {
            np->nAccel = (UINT)wParam;

            for (i = 0; i < (int)wParam; i++)
            {
                np->udAccel[i] = ((LPUDACCEL)lParam)[i];
            }
        }

        return TRUE;

    case UDM_GETACCEL:
        if (wParam > np->nAccel)
        {
            wParam = np->nAccel;
        }

        if (np->udAccel)
        {
            for (i=0; i<(int)wParam; ++i)
            {
                ((LPUDACCEL)lParam)[i] = np->udAccel[i];
            }
        }

        return np->nAccel;

    case WM_NOTIFYFORMAT:
        return CIHandleNotifyFormat(&np->ci, lParam);

    case WM_CREATE:
        // Allocate the instance data space.
        np = (PUDSTATE)LocalAlloc(LPTR, sizeof(UDSTATE));
        if (!np)
            return -1;

        SetWindowPtr(hwnd, 0, np);

        #define lpCreate ((CREATESTRUCT *)lParam)
        CIInitialize(&np->ci, hwnd, lpCreate);

        np->hTheme = OpenThemeData(np->ci.hwnd, L"Spin");

        // np->fUp =
        // np->fDown =
            // np->fUnsigned =
            // np->fSharedBorder =
            // np->fSunkenBorder =
        //  FALSE;

        if (lpCreate->style & UDS_UNSIGNED)
            np->fUnsigned = TRUE;

        if (lpCreate->dwExStyle & WS_EX_CLIENTEDGE)
            np->fSunkenBorder = TRUE;

        np->nBase = BASE_DECIMAL;
        np->nUpper = 0;
        np->nLower = 100;
        np->nPos = 0;
        np->hwndBuddy = NULL;
        np->uClass = CLASS_UNKNOWN;
        ASSERT(np->cReenterSetint == 0);

        np->udAccel = (UDACCEL *)LocalAlloc(LPTR, sizeof(UDACCEL) * NUM_UDACCELS);
        if (np->udAccel)
        {
            np->nAccel = NUM_UDACCELS;

            np->udAccel[0].nSec = 0;
            np->udAccel[0].nInc = 1;

            np->udAccel[1].nSec = 2;
            np->udAccel[1].nInc = 5;

            np->udAccel[2].nSec = 5;
            np->udAccel[2].nInc = 20;
        }
        else
        {
            np->nAccel = 0;
        }

        /* This does the pickbuddy and anchor
         */
        setbuddy(np, NULL);
        setint(np);

        // Automatically enable hot tracking if themes are being used
        if (np->hTheme)
            np->ci.style |= UDS_HOTTRACK;

        break;

    case WM_DESTROY:
        if (np) 
        {

            if (np->hTheme)
            {
                CloseThemeData(np->hTheme);
                np->hTheme = NULL;
            }

            if (np->hThemeBuddy)
            {
                CloseThemeData(np->hThemeBuddy);
                np->hThemeBuddy = NULL;
            }

            if (np->udAccel)
            {
                LocalFree((HLOCAL)np->udAccel);
            }

            if (np->hwndBuddy)
            {
                //  Our buddy needs to be unsubclassed, which we'll do
                //  in response to WM_NCDESTROY;  doing so now would 
                //  bust any subsequent call to the suclass proc.
                DebugMsg(DM_TRACE, TEXT("UpDown Destroyed while buddy subclassed"));
                np->fUpDownDestroyed = TRUE;
            }
            else
            {
                LocalFree((HLOCAL)np);
            }

            SetWindowPtr(hwnd, 0, 0);
        }

        break;

    case WM_GETOBJECT:
        if( lParam == OBJID_QUERYCLASSNAMEIDX )
            return MSAA_CLASSNAMEIDX_UPDOWN;
        goto DoDefault;

    default:
    {
        if (CCWndProc(&np->ci, uMsg, wParam, lParam, &lres))
            return lres;
    }

DoDefault:
        return DefWindowProc(hwnd, uMsg, wParam, lParam);
    }

    return 0L;
}

/////////////////////////////////////////////////////////////////////////////

// InitUpDownClass:
// Adds our WNDCLASS to the system.
//
#pragma code_seg(CODESEG_INIT)

BOOL InitUpDownClass(HINSTANCE hInst)
{
    WNDCLASS wndclass;

    wndclass.lpfnWndProc    = UpDownWndProc;
    wndclass.lpszClassName  = s_szUpdownClass;
    wndclass.hInstance  = hInst;
    wndclass.hCursor    = LoadCursor(NULL, IDC_ARROW);
    wndclass.hIcon      = NULL;
    wndclass.lpszMenuName   = NULL;
    wndclass.hbrBackground  = (HBRUSH)(COLOR_BTNFACE + 1);
    wndclass.style      = CS_HREDRAW | CS_VREDRAW | CS_GLOBALCLASS;
    wndclass.cbClsExtra = 0;
    wndclass.cbWndExtra = sizeof(PUDSTATE);

    if (!RegisterClass(&wndclass) && !GetClassInfo(hInst, s_szUpdownClass, &wndclass))
        return FALSE;
    return TRUE;
}
#pragma code_seg()