path: root/alf/alfnotebook.cpp

#include "alfpriv.h"
#include "alfcompat.h"

#define TABP_BODY 10
#define TMT_FILLCOLORHINT 3821

typedef struct {
    HWND     hwndTabCtrl;
    HTHEME   hTheme;
    ALFColor tabPaneBgColor;
    DWORD    flags;
    int      dpi;
    int      prevSelectedIndex;
} ALFNotebookPriv;

typedef struct {
    TCITEMHEADER header;
    DWORD        layoutFlags;
    HWND         panel;
} ALFNotebookPage;

static ALFNotebookPriv *
ALF_Notebook_CreatePriv(void)
{
    ALFNotebookPriv *priv = ALF_New(ALFNotebookPriv, 1);

    priv->tabPaneBgColor = ALF_COLOR_SYS(COLOR_BTNFACE);
    priv->prevSelectedIndex = -1;

    return priv;
}

void
ALF_Notebook_FreePriv(ALFNotebookPriv *priv)
{
    ALF_Compat_CloseThemeData(priv->hTheme);
    priv->hTheme = NULL;
    ALF_Free(priv);
}

static int
ALF_Notebook_InternalTabCount(HWND notebook, HWND tabControl)
{
    (void)notebook;
    return TabCtrl_GetItemCount(tabControl);
}

static HWND
ALF_Notebook_InternalTabPanel(HWND notebook, HWND tabControl, int index)
{
    (void)notebook;

    ALFNotebookPage p;
    ZeroMemory(&p, sizeof(p));

    p.header.mask = TCIF_PARAM;

    if (TabCtrl_GetItem(tabControl, index, &p)) {
        return p.panel;
    } else {
        return NULL;
    }
}

static int
ALF_Notebook_InternalSelectedIndex(HWND notebook, HWND tabControl)
{
    (void)notebook;

    return TabCtrl_GetCurSel(tabControl);
}


static void
ALF_Notebook_InternalHandleTabChange(HWND hwndNotebook, ALFNotebookPriv *priv)
{
    int selectedIndex = ALF_Notebook_InternalSelectedIndex(hwndNotebook, priv->hwndTabCtrl);
    int n = ALF_Notebook_InternalTabCount(hwndNotebook, priv->hwndTabCtrl);

    for (int i = 0; i < n; ++i) {
        if (i == selectedIndex) {
            SetWindowPos(ALF_Notebook_InternalTabPanel(hwndNotebook, priv->hwndTabCtrl, i), HWND_TOP, 0, 0, 0, 0, SWP_NOACTIVATE | SWP_NOSIZE | SWP_NOMOVE | SWP_SHOWWINDOW);
        } else {
            ShowWindow(ALF_Notebook_InternalTabPanel(hwndNotebook, priv->hwndTabCtrl, i), SW_HIDE);
        }
    }

    if (selectedIndex != priv->prevSelectedIndex) {
        HWND currentFocus = GetFocus();
        if (currentFocus != priv->hwndTabCtrl) {
            HWND focusControl = GetNextDlgTabItem(hwndNotebook, priv->hwndTabCtrl, FALSE);
            ALF_SetFocus(focusControl);
        }
    }

    priv->prevSelectedIndex = selectedIndex;
}

static void
ALF_Notebook_SetSingleTabBackground(HWND hwndNotebook, ALFNotebookPriv *priv, HWND panel)
{
    (void)hwndNotebook;
    SendMessage(panel, ALF_WM_SETBGCOLOR, 0, (LPARAM)priv->tabPaneBgColor);
}

static void
ALF_Notebook_SetAllTabBackgrounds(HWND hwndNotebook, ALFNotebookPriv *priv)
{
    int n = ALF_Notebook_InternalTabCount(hwndNotebook, priv->hwndTabCtrl);
    for (int i = 0; i < n; ++i) {
        ALFNotebookPage p;
        ZeroMemory(&p, sizeof(p));
        p.header.mask = TCIF_PARAM;

        if (TabCtrl_GetItem(priv->hwndTabCtrl, i, &p)) {
            if (p.layoutFlags & ALF_LAYOUT_INHERITBGCOLOR) {
                ALF_Notebook_SetSingleTabBackground(hwndNotebook, priv, p.panel);
            }
        }
    }
}

static void
ALF_Notebook_PropagateFontToPages(HWND hwndNotebook, ALFNotebookPriv *priv, HFONT font, LPARAM lparam)
{
    int n = ALF_Notebook_InternalTabCount(hwndNotebook, priv->hwndTabCtrl);
    for (int i = 0; i < n; ++i) {
        ALFNotebookPage p;
        ZeroMemory(&p, sizeof(p));
        p.header.mask = TCIF_PARAM;

        if (TabCtrl_GetItem(priv->hwndTabCtrl, i, &p)) {
            if (p.layoutFlags & ALF_LAYOUT_INHERITFONT) {
                SendMessage(p.panel, WM_SETFONT, (WPARAM)font, lparam);
            }
        }
    }
}

static void
ALF_Notebook_PropagateDpiChange(HWND hwndNotebook, ALFNotebookPriv *priv, WPARAM wparam, LPARAM lparam)
{
    int n = ALF_Notebook_InternalTabCount(hwndNotebook, priv->hwndTabCtrl);
    for (int i = 0; i < n; ++i) {
        HWND hwndPanel = ALF_Notebook_TabPanel(hwndNotebook, i);
        SendMessage(hwndPanel, ALF_WM_DPICHANGE, wparam, lparam);
    }
}

static BOOL
ALF_Notebook_CheckSingleColorBits(void *bits, SIZE s, COLORREF *outColor)
{
    int l = s.cx * s.cy;

    DWORD c;
    CopyMemory(&c, bits, 4);
    c &= 0x00FFFFFF;

    for (int i = 1; i < l; ++i) {
        DWORD c2;
        CopyMemory(&c2, (char*)bits + i*4, 4);
        c2 &= 0x00FFFFFF;

        if (c2 != c)
            return FALSE;
    }

    *outColor = c;
    return TRUE;
}

static void
ALF_Notebook_InternalHandleThemeChange(HWND hwndNotebook, ALFNotebookPriv *priv)
{
    ALF_Compat_CloseThemeData(priv->hTheme);
    priv->hTheme = NULL;
    priv->tabPaneBgColor = ALF_COLOR_SYS(COLOR_BTNFACE);

    if (ALF_Compat_IsAppThemed())
        priv->hTheme = ALF_Compat_OpenThemeData(hwndNotebook, L"Tab");

    InvalidateRect(hwndNotebook, NULL, TRUE);
    ALF_InvalidateLayout(hwndNotebook);

    if (priv->hTheme) {
        if (priv->flags & ALF_NOTEBOOK_SOLID_TAB_BACKGROUND) {
            COLORREF c;
            if (SUCCEEDED(ALF_Compat_GetThemeColor(priv->hTheme, TABP_BODY, 0, TMT_FILLCOLORHINT, &c))) {
                priv->tabPaneBgColor = (ALFColor)c;
            }
        } else {
            priv->tabPaneBgColor = ALF_COLOR_TRANSPARENT;

            // SPEED HACK: check if tab pane background is a single solid color
            // Windows 10 really sucks at stretching a completely white bitmap
            HDC dcNotebook = GetDC(hwndNotebook);
            HDC dcMem = CreateCompatibleDC(dcNotebook);
            SIZE s;
            if (SUCCEEDED(ALF_Compat_GetThemePartSize(priv->hTheme, dcNotebook, TABP_BODY, 0, NULL, TS_TRUE, &s))) {
                BITMAPINFO bi;
                ZeroMemory(&bi, sizeof(bi));

                bi.bmiHeader.biSize = sizeof(bi.bmiHeader);
                bi.bmiHeader.biWidth = s.cx;
                bi.bmiHeader.biHeight = s.cy;
                bi.bmiHeader.biPlanes = 1;
                bi.bmiHeader.biBitCount = 32;
                bi.bmiHeader.biCompression = BI_RGB;

                void *bits = NULL;
                HBITMAP hDib = CreateDIBSection(dcMem, &bi, DIB_RGB_COLORS, &bits, NULL, 0);
                if (hDib) {
                    HBITMAP hbmOld = SelectBitmap(dcMem, hDib);

                    RECT r = { 0, 0, s.cx, s.cy };
                    if (SUCCEEDED(ALF_Compat_DrawThemeBackground(priv->hTheme, dcMem, TABP_BODY, 0, &r, NULL))) {
                        GdiFlush();

                        COLORREF c = 0;
                        if (ALF_Notebook_CheckSingleColorBits(bits, s, &c)) {
                            priv->tabPaneBgColor = (ALFColor)c;
                        }
                    }

                    SelectBitmap(dcMem, hbmOld);
                    DeleteObject(hDib);
                }
            }

            DeleteDC(dcMem);
            ReleaseDC(hwndNotebook, dcNotebook);
        }
    }

    ALF_Notebook_SetAllTabBackgrounds(hwndNotebook, priv);
}


static HWND
ALF_Notebook_InternalAddTab(HWND notebook, ALFNotebookPriv *priv, const TCHAR *title)
{
    RECT r;
    GetClientRect(priv->hwndTabCtrl, &r);
    TabCtrl_AdjustRect(priv->hwndTabCtrl, FALSE, &r);
    MapWindowRect(priv->hwndTabCtrl, notebook, &r);

    HWND hwndPanel = ALF_CreatePanelWindow(notebook, (WORD)-1);
    SetWindowPos(hwndPanel, NULL, r.left, r.top, r.right - r.left, r.bottom - r.top, SWP_HIDEWINDOW|SWP_NOACTIVATE|SWP_NOZORDER|SWP_NOOWNERZORDER);

    SendMessage(hwndPanel, WM_SETFONT, (WPARAM)SendMessage(priv->hwndTabCtrl, WM_GETFONT, 0, 0), 0);
    SendMessage(hwndPanel, ALF_WM_DPICHANGE, 0, (LPARAM)priv->dpi);

    ALF_Notebook_SetSingleTabBackground(notebook, priv, hwndPanel);

    ALFNotebookPage p;
    ZeroMemory(&p, sizeof(p));

    p.header.mask = TCIF_TEXT | TCIF_PARAM;
    p.header.pszText = (TCHAR*)title;
    p.layoutFlags = ALF_LAYOUT_INHERITBGCOLOR | ALF_LAYOUT_INHERITFONT;
    p.panel = hwndPanel;

    TabCtrl_InsertItem(priv->hwndTabCtrl, ALF_Notebook_InternalTabCount(notebook, priv->hwndTabCtrl), &p);
    ALF_Notebook_InternalHandleTabChange(notebook, priv);

    ALF_InvalidateLayout(notebook);

    return hwndPanel;
}


static LRESULT CALLBACK
ALF_Notebook_TabCtrlWndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    WNDPROC oldWndProc = (WNDPROC)GetWindowLongPtr(hwnd, GWLP_USERDATA);

    if (uMsg == WM_ERASEBKGND) {
        // see: http://www.virtualdub.org/blog/pivot/entry.php?id=291
        HDC hdc = (HDC)wParam;

        RECT r;
        GetClientRect(hwnd, &r);
        TabCtrl_AdjustRect(hwnd, FALSE, &r);

        ExcludeClipRect(hdc, r.left, r.top, r.right, r.bottom);
    }
    if (uMsg == WM_DESTROY) {
        SetWindowLongPtr(hwnd, GWLP_WNDPROC, (LONG_PTR)oldWndProc);
        SetWindowLongPtr(hwnd, GWLP_USERDATA, 0);
    }

    return CallWindowProc(oldWndProc, hwnd, uMsg, wParam, lParam);
}

static void
ALF_Notebook_InternalPaint(HWND hwnd, ALFNotebookPriv *priv, HDC dc, RECT *f)
{
    if (priv->hTheme != NULL) {
        RECT r;
        GetClientRect(priv->hwndTabCtrl, &r);
        TabCtrl_AdjustRect(priv->hwndTabCtrl, FALSE, &r);
        MapWindowRect(priv->hwndTabCtrl, hwnd, &r);

        SIZE s;
        if (SUCCEEDED(ALF_Compat_GetThemePartSize(priv->hTheme, dc, TABP_BODY, 0, NULL, TS_TRUE, &s))) {
            // windows dialog tab panes tile the background horizontally
            for (int x = r.left; x < r.right; x += s.cx) {
                RECT r2 = { x, r.top, x + s.cx, r.bottom };
                if (r2.right > r.right)
                    r2.right = r.right;

                if (f && r2.left > f->right && r2.right < f->left)
                    continue;

                if (RectVisible(dc, &r2))
                    ALF_Compat_DrawThemeBackground(priv->hTheme, dc, TABP_BODY, 0, &r2, NULL);
            }
        } else {
            // old version - let uxtheme stretch it
            ALF_Compat_DrawThemeBackground(priv->hTheme, dc, TABP_BODY, 0, &r, NULL);
        }

        ExcludeClipRect(dc, r.left, r.top, r.right, r.bottom);
    }

    FillRect(dc, f, GetSysColorBrush(COLOR_BTNFACE));
}

static DWORD
ALF_Notebook_GetWidgetFlags(HWND hwndNotebook, ALFNotebookPriv *priv, HWND widget)
{
    int n = ALF_Notebook_InternalTabCount(hwndNotebook, priv->hwndTabCtrl);
    for (int i = 0; i < n; ++i) {
        ALFNotebookPage p;
        ZeroMemory(&p, sizeof(p));
        p.header.mask = TCIF_PARAM;

        if (TabCtrl_GetItem(priv->hwndTabCtrl, i, &p)) {
            if (p.panel == widget) {
                return p.layoutFlags;
            }
        }
    }

    return 0;
}

static BOOL
ALF_Notebook_SetWidgetFlags(HWND hwndNotebook, ALFNotebookPriv *priv, HWND widget, DWORD flags)
{
    int n = ALF_Notebook_InternalTabCount(hwndNotebook, priv->hwndTabCtrl);
    for (int i = 0; i < n; ++i) {
        ALFNotebookPage p;
        ZeroMemory(&p, sizeof(p));
        p.header.mask = TCIF_PARAM;

        if (TabCtrl_GetItem(priv->hwndTabCtrl, i, &p)) {
            if (p.panel == widget) {
                if (p.layoutFlags == flags)
                    return TRUE;

                if ((flags & ALF_LAYOUT_INHERITFONT) && !(p.layoutFlags & ALF_LAYOUT_INHERITFONT)) {
                    SendMessage(p.panel, WM_SETFONT, (WPARAM)SendMessage(priv->hwndTabCtrl, WM_GETFONT, 0, 0), TRUE);
                }
                if ((flags & ALF_LAYOUT_INHERITBGCOLOR) && !(p.layoutFlags & ALF_LAYOUT_INHERITBGCOLOR)) {
                    ALF_Notebook_SetSingleTabBackground(hwndNotebook, priv, p.panel);
                }

                p.layoutFlags = flags;

                return TabCtrl_SetItem(priv->hwndTabCtrl, i, &p);
            }
        }
    }

    return FALSE;
}

static LRESULT CALLBACK
ALF_Notebook_WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    ALFNotebookPriv *priv = (ALFNotebookPriv *)GetWindowLongPtr(hwnd, 0);

    if (uMsg == WM_NOTIFY) {
        NMHDR *pnmh = (NMHDR*)lParam;
        if (pnmh->hwndFrom == priv->hwndTabCtrl && pnmh->code == TCN_SELCHANGE) {
            ALF_Notebook_InternalHandleTabChange(hwnd, priv);

            return TRUE;
        }
    }

    if (ALF_ShouldMessageBubble(hwnd, uMsg, wParam, lParam))
        return SendMessage(GetParent(hwnd), uMsg, wParam, lParam);

    if (uMsg == WM_CREATE && priv == NULL) {
        priv = ALF_Notebook_CreatePriv();
        priv->hwndTabCtrl = CreateWindowEx(0,
                                           WC_TABCONTROL,
                                           TEXT(""),
                                           WS_CHILD | WS_VISIBLE | WS_TABSTOP | WS_CLIPSIBLINGS,
                                           0, 0, 100, 100,
                                           hwnd,
                                           NULL,
                                           ALF_HINSTANCE,
                                           NULL);

        TabCtrl_SetItemExtra(priv->hwndTabCtrl, sizeof(ALFNotebookPage) - sizeof(TCITEMHEADER));

        LONG_PTR wndProc = GetWindowLongPtr(priv->hwndTabCtrl, GWLP_WNDPROC);
        SetWindowLongPtr(priv->hwndTabCtrl, GWLP_USERDATA, wndProc);
        SetWindowLongPtr(priv->hwndTabCtrl, GWLP_WNDPROC, (LONG_PTR)ALF_Notebook_TabCtrlWndProc);

        SetWindowLongPtr(hwnd, 0, (LONG_PTR)priv);
        ALF_Notebook_InternalHandleThemeChange(hwnd, priv);
    }

    if (!priv)
        return DefWindowProc(hwnd, uMsg, wParam, lParam);

    if (uMsg == WM_DESTROY) {
        ALF_Notebook_FreePriv(priv);
        SetWindowLongPtr(hwnd, 0, 0);
        priv = NULL;
    } else if (uMsg == WM_SETFONT) {
        SendMessage(priv->hwndTabCtrl, WM_SETFONT, wParam, lParam);

        ALF_Notebook_PropagateFontToPages(hwnd, priv, (HFONT)wParam, lParam);

        ALF_InvalidateLayout(hwnd);
    } else if (uMsg == WM_GETFONT) {
        return SendMessage(priv->hwndTabCtrl, WM_GETFONT, wParam, lParam);
    } else if (uMsg == ALF_WM_QUERYSIZE) {
        int n = ALF_Notebook_InternalTabCount(hwnd, priv->hwndTabCtrl);
        RECT r = { 0, 0, 0, 0 };
        for (int i = 0; i < n; ++i) {
            HWND p = ALF_Notebook_InternalTabPanel(hwnd, priv->hwndTabCtrl, i);
            SIZE s = { 0, 0 };
            SendMessage(p, ALF_WM_QUERYSIZE, 0, (LPARAM)&s);
            if (s.cx > r.right)
                r.right = s.cx;
            if (s.cy > r.bottom)
                r.bottom = s.cy;
        }

        if (!r.right)
            r.right = 100; // FIXME!
        if (!r.bottom)
            r.bottom = 100; // FIXME!

        TabCtrl_AdjustRect(priv->hwndTabCtrl, TRUE, &r);

        SIZE *ps = (SIZE*)lParam;
        if (ps->cx < r.right - r.left) {
            ps->cx = r.right - r.left;
        }

        if (ps->cy < r.bottom - r.top) {
            ps->cy = r.bottom - r.top;
        }

        return 0;
    } else if (uMsg == WM_WINDOWPOSCHANGED) {
        WINDOWPOS *pos = (WINDOWPOS *)lParam;
        if (!(pos->flags & SWP_NOSIZE)) {
            RECT r;
            GetClientRect(hwnd, &r);
            int n = ALF_Notebook_InternalTabCount(hwnd, priv->hwndTabCtrl);

            RECT oldR;
            GetWindowRect(priv->hwndTabCtrl, &oldR);
            TabCtrl_AdjustRect(priv->hwndTabCtrl, FALSE, &oldR);

            HDWP hdwp = BeginDeferWindowPos(n+1);

            // SWP_COPYBITS: NT 3.51 sadness, will not invalidate bottom edge properly on resize
            // even though it redraws everything else with great flicker
            // the flicker problem is present in every other version of windows, too
            hdwp = DeferWindowPos(hdwp, priv->hwndTabCtrl, NULL,
                                  0, 0, r.right-r.left, r.bottom-r.top,
                                  SWP_NOMOVE|SWP_NOACTIVATE|SWP_NOZORDER|SWP_NOCOPYBITS);

            TabCtrl_AdjustRect(priv->hwndTabCtrl, FALSE, &r);

            for (int i = 0; i < n; ++i) {
                HWND p = ALF_Notebook_InternalTabPanel(hwnd, priv->hwndTabCtrl, i);

                hdwp = DeferWindowPos(hdwp, p, NULL,
                                      r.left, r.top, r.right - r.left, r.bottom - r.top,
                                      SWP_NOACTIVATE|SWP_NOZORDER);
            }

            EndDeferWindowPos(hdwp);

            if (priv->hTheme
                    && priv->tabPaneBgColor == ALF_COLOR_TRANSPARENT
                    && ((oldR.bottom - oldR.top) != (r.bottom - r.top))) {
                // only needed when height changes, since bg is tiled horizontally
                HWND panel = ALF_Notebook_SelectedPanel(hwnd);
                if (panel != NULL)
                    ALF_InvalidateBackground(panel);
            }
        }
    } else if (uMsg == ALF_WM_NTBK_ADDTAB) {
        return (LRESULT)ALF_Notebook_InternalAddTab(hwnd, priv, (TCHAR *)lParam);
    } else if (uMsg == ALF_WM_NTBK_TABCOUNT) {
        return (LRESULT)ALF_Notebook_InternalTabCount(hwnd, priv->hwndTabCtrl);
    } else if (uMsg == ALF_WM_NTBK_GETPANEL) {
        return (LRESULT)ALF_Notebook_InternalTabPanel(hwnd, priv->hwndTabCtrl, (int)lParam);
    } else if (uMsg == ALF_WM_NTBK_GETSELINDEX) {
        return (LRESULT)ALF_Notebook_InternalSelectedIndex(hwnd, priv->hwndTabCtrl);
    } else if (uMsg == WM_THEMECHANGED) {
        ALF_Notebook_InternalHandleThemeChange(hwnd, priv);
    } else if (uMsg == WM_ERASEBKGND) {
        return TRUE;
    } else if (uMsg == WM_PRINTCLIENT) {
        RECT r = {0, 0, 0, 0};
        GetClientRect(hwnd, &r);

        ALF_Notebook_InternalPaint(hwnd, priv, (HDC)wParam, &r);
        return TRUE;
    } else if (uMsg == WM_PAINT) {
        PAINTSTRUCT ps;
        HDC dc = BeginPaint(hwnd, &ps);

        ALF_Notebook_InternalPaint(hwnd, priv, dc, &ps.rcPaint);

        EndPaint(hwnd, &ps);
        return 0;
    } else if (uMsg == ALF_WM_INVALIDATELAYOUT) {
        ALF_InvalidateLayout(GetParent(hwnd));
    } else if (uMsg == ALF_WM_NTBK_GETFLAGS) {
        return (LRESULT)priv->flags;
    } else if (uMsg == ALF_WM_NTBK_SETFLAGS) {
        DWORD oldFlags = priv->flags;
        priv->flags = (DWORD)lParam;

        if ((oldFlags & ALF_NOTEBOOK_SOLID_TAB_BACKGROUND) != (priv->flags & ALF_NOTEBOOK_SOLID_TAB_BACKGROUND)) {
            ALF_Notebook_InternalHandleThemeChange(hwnd, priv);
        }
    } else if (uMsg == ALF_WM_LYT_GETWDGTFLAGS) {
        return (LRESULT)ALF_Notebook_GetWidgetFlags(hwnd, priv, (HWND)wParam);
    } else if (uMsg == ALF_WM_LYT_SETWDGTFLAGS) {
        return (LRESULT)ALF_Notebook_SetWidgetFlags(hwnd, priv, (HWND)wParam, (DWORD)lParam);
    } else if (uMsg == ALF_WM_DPICHANGE) {
        priv->dpi = (int)lParam;
        ALF_Notebook_PropagateDpiChange(hwnd, priv, wParam, lParam);
        return TRUE;
    }

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

// tab control
HWND
ALF_AddNotebook(HWND parent, WORD id, int x, int y)
{
    HWND hwndNtbk  = ALF_CreateControlWindow(WS_EX_CONTROLPARENT,
                                             TEXT(""),
                                             WS_CHILD | WS_VISIBLE | WS_CLIPCHILDREN,
                                             0, 0, 100, 100,
                                             parent,
                                             (HMENU)(ULONG_PTR)id,
                                             ALF_Notebook_WindowProc,
                                             NULL);

    ALF_AddWidget(parent, x, y, hwndNtbk, 0, 0, ALF_LAYOUT_SIZE_QUERY | ALF_LAYOUT_INHERITFONT | ALF_LAYOUT_SENDDPICHANGE);

    return hwndNtbk;
}

HWND
ALF_Notebook_AddTab(HWND notebook, const TCHAR *title)
{
    return (HWND)SendMessage(notebook, ALF_WM_NTBK_ADDTAB, 0, (LPARAM)title);
}

int
ALF_Notebook_TabCount(HWND notebook)
{
    return (int)SendMessage(notebook, ALF_WM_NTBK_TABCOUNT, 0, 0);
}

int
ALF_Notebook_TabIndex(HWND notebook, HWND tabPanel);

HWND
ALF_Notebook_TabPanel(HWND notebook, int index)
{
    return (HWND)SendMessage(notebook, ALF_WM_NTBK_GETPANEL, 0, (LPARAM)index);
}

int
ALF_Notebook_SelectedIndex(HWND notebook)
{
    return (int)SendMessage(notebook, ALF_WM_NTBK_GETSELINDEX, 0, 0);
}

HWND
ALF_Notebook_SelectedPanel(HWND notebook)
{
    int i = ALF_Notebook_SelectedIndex(notebook);
    if (i >= 0) {
        return ALF_Notebook_TabPanel(notebook, i);
    } else {
        return NULL;
    }
}

DWORD
ALF_Notebook_Flags(HWND notebook)
{
    return (DWORD)SendMessage(notebook, ALF_WM_NTBK_GETFLAGS, 0, 0);
}

void
ALF_Notebook_SetFlags(HWND notebook, DWORD flags)
{
    SendMessage(notebook, ALF_WM_NTBK_SETFLAGS, 0, (LPARAM)flags);
}