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

#define ALF_NB_ADDTAB       (ALF_WM__BASE + 300)
#define ALF_NB_TABCOUNT     (ALF_WM__BASE + 301)
#define ALF_NB_GETPANEL     (ALF_WM__BASE + 302)
#define ALF_NB_GETSELINDEX  (ALF_WM__BASE + 303)
#define ALF_NB_GETPNLINDEX  (ALF_WM__BASE + 304)

#define TABP_BODY 10
#define TMT_FILLCOLORHINT 3821

TCHAR *_alf_notebookClass = NULL;

typedef struct {
    HWND     hwndTabCtrl;
    HTHEME   hTheme;
    ALFColor themeTabBgColor;
    DWORD    flags;
} ALFNotebookPriv;

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

    priv->themeTabBgColor = ALF_COLOR_SYS(COLOR_BTNFACE);

    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;

    TCITEM tci;
    ZeroMemory(&tci, sizeof(tci));

    tci.mask = TCIF_PARAM;

    if (TabCtrl_GetItem(tabControl, index, &tci)) {
        return (HWND)tci.lParam;
    } 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, HWND hwndTabCtrl)
{
    int selectedIndex = ALF_Notebook_InternalSelectedIndex(hwndNotebook, hwndTabCtrl);
    int n = ALF_Notebook_InternalTabCount(hwndNotebook, hwndTabCtrl);

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

static void
ALF_Notebook_SetSingleTabBackground(HWND hwndNotebook, ALFNotebookPriv *priv, HWND panel)
{
    (void)hwndNotebook;
    if (priv->hTheme && !(priv->flags & ALF_NOTEBOOK_SOLID_TAB_BACKGROUND)) {
        SendMessage(panel, ALF_WM_SETBGCOLOR, 0, (LPARAM)ALF_COLOR_TRANSPARENT);
    } else {
        SendMessage(panel, ALF_WM_SETBGCOLOR, 0, (LPARAM)priv->themeTabBgColor);
    }
}

static void
ALF_Notebook_SetAllTabBackgrounds(HWND hwndNotebook, ALFNotebookPriv *priv)
{
    int n = ALF_Notebook_InternalTabCount(hwndNotebook, priv->hwndTabCtrl);
    for (int i = 0; i < n; ++i) {
        HWND panel = ALF_Notebook_InternalTabPanel(hwndNotebook, priv->hwndTabCtrl, i);
        ALF_Notebook_SetSingleTabBackground(hwndNotebook, priv, panel);
    }
}

static void
ALF_Notebook_InternalHandleThemeChange(HWND hwndNotebook, ALFNotebookPriv *priv)
{
    ALF_Compat_CloseThemeData(priv->hTheme);
    priv->hTheme = NULL;
    if (ALF_Compat_IsAppThemed())
        priv->hTheme = ALF_Compat_OpenThemeData(hwndNotebook, L"Tab");

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

    // tab fill color for solid bg color mode
    priv->themeTabBgColor = ALF_COLOR_SYS(COLOR_BTNFACE);
    if (priv->hTheme) {
        COLORREF c;
        if (SUCCEEDED(ALF_Compat_GetThemeColor(priv->hTheme, TABP_BODY, 0, TMT_FILLCOLORHINT, &c))) {
            priv->themeTabBgColor = (ALFColor)c;
        }
    }

    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);

    ALF_Notebook_SetSingleTabBackground(notebook, priv, hwndPanel);

    TCITEM tie;
    ZeroMemory(&tie, sizeof(tie));

    tie.mask = TCIF_TEXT | TCIF_PARAM;
    tie.pszText = (TCHAR*)title;
    tie.lParam = (LPARAM)hwndPanel;

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

    ALF_InvalidateLayout(notebook);

    return hwndPanel;
}


static LRESULT CALLBACK
ALF_Notebook_TabCtrlSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData)
{
    (void)uIdSubclass;
    (void)dwRefData;

    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 == 0x2000 + WM_NOTIFY) {
        NMHDR *pnmh = (NMHDR*)lParam;
        if (pnmh->code == TCN_SELCHANGE) {
            ALF_Notebook_InternalHandleTabChange(GetParent(hwnd), hwnd);

            return TRUE;
        }
    }
    if (uMsg == WM_DESTROY) {
        ALF_Compat_RemoveWindowSubclass(hwnd, ALF_Notebook_TabCtrlSubclassProc, 0);
    }

    return ALF_Compat_DefSubclassProc(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;

                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 LRESULT CALLBACK
ALF__NotebookWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    if (ALF_ShouldMessageBubble(hwnd, uMsg, wParam, lParam))
        return SendMessage(GetParent(hwnd), uMsg, wParam, lParam);

    ALFNotebookPriv *priv = (ALFNotebookPriv *)GetWindowLongPtr(hwnd, 0);

    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);

        ALF_Compat_SetWindowSubclass(priv->hwndTabCtrl, ALF_Notebook_TabCtrlSubclassProc, 0, 0);

        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);

        int n = ALF_Notebook_InternalTabCount(hwnd, priv->hwndTabCtrl);
        for (int i = 0; i < n; ++i) {
            HWND p = ALF_Notebook_InternalTabPanel(hwnd, priv->hwndTabCtrl, i);
            SendMessage(p, WM_SETFONT, 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) {
            ps->cx = r.right - r.left;
        }

        if (!ps->cy) {
            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);

            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 && ((oldR.bottom - oldR.top) != (r.bottom - r.top))) {
                // only needed when height changes, since bg is tiled horizontally
                HWND panel = ALF_NotebookSelectedPanel(hwnd);
                if (panel != NULL)
                    ALF_InvalidateBackground(panel);
            }
        }
    } else if (uMsg == ALF_NB_ADDTAB) {
        return (LRESULT)ALF_Notebook_InternalAddTab(hwnd, priv, (TCHAR *)lParam);
    } else if (uMsg == ALF_NB_TABCOUNT) {
        return (LRESULT)ALF_Notebook_InternalTabCount(hwnd, priv->hwndTabCtrl);
    } else if (uMsg == ALF_NB_GETPANEL) {
        return (LRESULT)ALF_Notebook_InternalTabPanel(hwnd, priv->hwndTabCtrl, (int)lParam);
    } else if (uMsg == ALF_NB_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_SetAllTabBackgrounds(hwnd, priv);
        }
    }

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

void
ALF_RegisterNotebookClass(void)
{
    WNDCLASS cls;
    ZeroMemory(&cls, sizeof(cls));

    TCHAR  classNameBuf[256];
    ALF_BuildUniqueName(classNameBuf, TEXT("ALFNotebook."), (ULONG_PTR)&_alf_notebookClass);

    cls.hInstance = ALF_HINSTANCE;
    cls.hCursor = LoadCursor(NULL, (LPTSTR)IDC_ARROW);
    cls.lpszClassName = classNameBuf;
    cls.cbWndExtra = sizeof(ALFNotebookPriv*);
    cls.lpfnWndProc = ALF__NotebookWindowProc;

    ATOM classatom = RegisterClass(&cls);
    if (!classatom)
        MessageBox(NULL, TEXT("FATAL: Could not register notebook class"), NULL, MB_OK);

    _alf_notebookClass = MAKEINTATOM(classatom);
}

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

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

    return hwndNtbk;
}

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

int
ALF_NotebookTabCount(HWND notebook)
{
    return (int)SendMessage(notebook, ALF_NB_TABCOUNT, 0, 0);
}

int
ALF_NotebookTabIndex(HWND notebook, HWND tabPanel);

HWND
ALF_NotebookTabPanel(HWND notebook, int index)
{
    return (HWND)SendMessage(notebook, ALF_NB_GETPANEL, 0, (LPARAM)index);
}

int
ALF_NotebookSelectedIndex(HWND notebook)
{
    return (int)SendMessage(notebook, ALF_NB_GETSELINDEX, 0, 0);
}

HWND
ALF_NotebookSelectedPanel(HWND notebook)
{
    int i = ALF_NotebookSelectedIndex(notebook);
    if (i >= 0) {
        return ALF_NotebookTabPanel(notebook, i);
    } else {
        return NULL;
    }
}

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

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