#include "alfpriv.h"

#define BP_PUSHBUTTON 1
#define PBS_NORMAL 1
#define PBS_HOT 2
#define PBS_PRESSED 3
#define PBS_DISABLED 4
#define PBS_DEFAULTED 5
#define PBS_DEFAULTED_ANIMATING 6


typedef struct {
    BOOL isDefault;
    BOOL isHot;
    HTHEME hTheme;
    int uxStatePrev;
    int uxStateCurrent;
    UINT itemStatePrev;
    UINT itemStateCurrent;
    DWORD uxDefaultAnimationDuration;
    BOOL uxIsDefaultAnimating;
    int dpi;
} ALFButtonPriv;

static void CALLBACK
ALF__Button_DefaultAnimatingTimerProc(HWND hwnd, UINT uMsg, UINT_PTR idEvent, DWORD dwTime)
{
    (void)uMsg;
    (void)dwTime;
    ALFButtonPriv *priv = (ALFButtonPriv *)idEvent;

    priv->uxIsDefaultAnimating = !priv->uxIsDefaultAnimating;
    InvalidateRect(hwnd, NULL, FALSE);
}

static BOOL CALLBACK
ALF__Button_Text_DrawStateProc(HDC hdc, LPARAM lData,  WPARAM wData, int cx, int cy)
{
    (void)wData;

    int oldBkMode = SetBkMode(hdc, TRANSPARENT);

    RECT r = { 0, 0, cx, cy };
    DrawText(hdc, (TCHAR*)lData, -1, &r, (UINT)wData);

    SetBkMode(hdc, oldBkMode);

    return TRUE;
}

static void
ALF__Button_RenderUxtheme(HWND hwnd, ALFButtonPriv *priv, int uxstate, UINT itemState, HDC hDC, LPRECT pRcItem)
{
    if (ALF_Compat_IsThemeBackgroundPartiallyTransparent(priv->hTheme, BP_PUSHBUTTON, uxstate)) {
        ALF_Compat_DrawThemeParentBackground(hwnd, hDC, pRcItem);
    }

    RECT r = *pRcItem;
    InflateRect(&r, 1, 1); // HACK! get rid of 1px transparent border

    ALF_Compat_DrawThemeBackground(priv->hTheme, hDC, BP_PUSHBUTTON, uxstate, &r, pRcItem);

    RECT content = r;
    ALF_Compat_GetThemeBackgroundContentRect(priv->hTheme, hDC, BP_PUSHBUTTON, uxstate, &r, &content);

    if ((itemState & ODS_FOCUS) && !(itemState & ODS_NOFOCUSRECT))
        DrawFocusRect(hDC, &content);

    int textlen = GetWindowTextLengthW(hwnd);
    WCHAR *textbuf = ALF_New(WCHAR, (SIZE_T)textlen + 1);
    GetWindowTextW(hwnd, textbuf, textlen+1);

    UINT style = DT_CENTER;

    if (itemState & ODS_NOACCEL)
        style |= DT_HIDEPREFIX;

    RECT textbounds = content;
    ALF_Compat_GetThemeTextExtent(priv->hTheme, hDC, BP_PUSHBUTTON, uxstate, textbuf, -1, style, &content, &textbounds);

    RECT texttarget = content;
    texttarget.top += ((content.bottom - content.top) - (textbounds.bottom - textbounds.top)) / 2;
    texttarget.left += ((content.right - content.left) - (textbounds.right - textbounds.left)) / 2;
    texttarget.right = texttarget.left + (textbounds.right - textbounds.left);
    texttarget.bottom = texttarget.top + (textbounds.bottom - textbounds.top);

    ALF_Compat_DrawThemeText(priv->hTheme, hDC, BP_PUSHBUTTON, uxstate, textbuf, -1, style, 0, &texttarget);

    ALF_Free(textbuf);
}

static void
ALF__Button_Render95(HWND hwnd, ALFButtonPriv *priv, LPDRAWITEMSTRUCT dis)
{
    RECT r = dis->rcItem;

    TCHAR *textbuf = ALF_Text(hwnd);

    if (priv->isDefault) {
        HBRUSH framecolor = GetSysColorBrush(COLOR_WINDOWFRAME);
        FrameRect(dis->hDC, &r, framecolor);
        InflateRect(&r, -1, -1);
    }

    UINT dfcs = DFCS_BUTTONPUSH | DFCS_ADJUSTRECT;
    if (dis->itemState & ODS_SELECTED)
        dfcs |= DFCS_FLAT;
    if (dis->itemState & ODS_DISABLED)
        dfcs |= DFCS_INACTIVE;
    if (dis->itemState & ODS_HOTLIGHT)
        dfcs |= DFCS_HOT;

    DrawFrameControl(dis->hDC, &r, DFC_BUTTON, dfcs);

    if ((dis->itemState & ODS_FOCUS) && !(dis->itemState & ODS_NOFOCUSRECT)) {
        RECT f = r;
        InflateRect(&f, -1, -1);
        DrawFocusRect(dis->hDC, &f);
    }

    RECT textbounds = dis->rcItem;
    DrawText(dis->hDC, textbuf, -1, &textbounds, DT_LEFT | DT_CALCRECT);

    RECT texttarget = dis->rcItem;
    texttarget.top += ((dis->rcItem.bottom - dis->rcItem.top) - (textbounds.bottom - textbounds.top)) / 2 - 1;
    texttarget.left += ((dis->rcItem.right - dis->rcItem.left) - (textbounds.right - textbounds.left)) / 2;
    texttarget.right = texttarget.left + (textbounds.right - textbounds.left);
    texttarget.bottom = texttarget.top + (textbounds.bottom - textbounds.top);

    if (dis->itemState & ODS_SELECTED) {
        texttarget.top += 1;
        texttarget.left += 1;
        texttarget.right += 1;
        texttarget.bottom += 1;
    }

    UINT style = DT_CENTER;

    if (dis->itemState & ODS_NOACCEL)
        style |= DT_HIDEPREFIX;

    if (dis->itemState & ODS_DISABLED) {
        if (ALF_Compat_IsWin9x()) {
            // Win9x just uses gray text. DSS_DISABLED is broken there, too,
            // so we can't get the NT look even if we wanted to
            COLORREF oldTextColor = SetTextColor(dis->hDC, GetSysColor(COLOR_GRAYTEXT));

            POINT oldorg = { 0, 0 };
            SetViewportOrgEx(dis->hDC, texttarget.left, texttarget.top, &oldorg);
            ALF__Button_Text_DrawStateProc(dis->hDC, (LPARAM)textbuf, (WPARAM)style,
                                        texttarget.right - texttarget.left, texttarget.bottom - texttarget.top);
            SetViewportOrgEx(dis->hDC, oldorg.x, oldorg.y, NULL);

            SetTextColor(dis->hDC, oldTextColor);
        } else {
            DrawState(dis->hDC, NULL, ALF__Button_Text_DrawStateProc,
                    (LPARAM)textbuf, (WPARAM)style,
                    texttarget.left, texttarget.top,
                    texttarget.right - texttarget.left, texttarget.bottom - texttarget.top,
                    DST_COMPLEX | DSS_DISABLED);
        }
    } else {
        POINT oldorg = { 0, 0 };

        SetViewportOrgEx(dis->hDC, texttarget.left, texttarget.top, &oldorg);
        ALF__Button_Text_DrawStateProc(dis->hDC, (LPARAM)textbuf, (WPARAM)style,
                                    texttarget.right - texttarget.left, texttarget.bottom - texttarget.top);
        SetViewportOrgEx(dis->hDC, oldorg.x, oldorg.y, NULL);
    }

    ALF_Free(textbuf);
}

static void
ALF__Button_Render3x(HWND hwnd, ALFButtonPriv *priv, LPDRAWITEMSTRUCT dis)
{
    RECT r = dis->rcItem;

    ALF_Compat_DrawThemeParentBackground(hwnd, dis->hDC, &r);

    TCHAR *textbuf = ALF_Text(hwnd);

    HBRUSH framecolor = GetSysColorBrush(COLOR_WINDOWFRAME);
    HBRUSH facecolor = GetSysColorBrush(COLOR_BTNFACE);

    // black frame
    if (priv->isDefault) {
        RECT rt = { r.left + 1, r.top, r.right - 1, r.top + 2 };
        RECT rl = { r.left, r.top + 1, r.left + 2, r.bottom - 1 };
        RECT rr = { r.right - 2, r.top + 1, r.right, r.bottom - 1 };
        RECT rb = { r.left + 1, r.bottom - 2, r.right - 1, r.bottom };
        FillRect(dis->hDC, &rt, framecolor);
        FillRect(dis->hDC, &rl, framecolor);
        FillRect(dis->hDC, &rr, framecolor);
        FillRect(dis->hDC, &rb, framecolor);
        InflateRect(&r, -2, -2);
    } else {
        RECT rt = { r.left + 1, r.top, r.right - 1, r.top + 1 };
        RECT rl = { r.left, r.top + 1, r.left + 1, r.bottom - 1 };
        RECT rr = { r.right - 1, r.top + 1, r.right, r.bottom - 1 };
        RECT rb = { r.left + 1, r.bottom - 1, r.right - 1, r.bottom };
        FillRect(dis->hDC, &rt, framecolor);
        FillRect(dis->hDC, &rl, framecolor);
        FillRect(dis->hDC, &rr, framecolor);
        FillRect(dis->hDC, &rb, framecolor);
        InflateRect(&r, -1, -1);
    }

    // 3d button
    if (dis->itemState & ODS_SELECTED) {
        DrawEdge(dis->hDC, &r, BDR_SUNKENOUTER, BF_TOPLEFT);

        RECT f = r;
        f.left++;
        f.top++;

        FillRect(dis->hDC, &f, facecolor);

        InflateRect(&r, -2, -2);
    } else {
        DrawEdge(dis->hDC, &r, BDR_RAISEDINNER, BF_RECT);
        InflateRect(&r, -1, -1);
        DrawEdge(dis->hDC, &r, BDR_RAISEDINNER, BF_RECT);
        InflateRect(&r, -1, -1);

        FillRect(dis->hDC, &r, facecolor);
    }

    RECT textbounds = dis->rcItem;
    DrawText(dis->hDC, textbuf, -1, &textbounds, DT_LEFT | DT_CALCRECT);

    RECT texttarget = dis->rcItem;
    texttarget.top += ((dis->rcItem.bottom - dis->rcItem.top) - (textbounds.bottom - textbounds.top)) / 2;
    texttarget.left += ((dis->rcItem.right - dis->rcItem.left) - (textbounds.right - textbounds.left)) / 2;
    texttarget.right = texttarget.left + (textbounds.right - textbounds.left);
    texttarget.bottom = texttarget.top + (textbounds.bottom - textbounds.top);

    if (dis->itemState & ODS_SELECTED) {
        texttarget.top += 1;
        texttarget.left += 1;
        texttarget.right += 1;
        texttarget.bottom += 1;
    }

    if (dis->itemState & ODS_FOCUS) {
        DrawFocusRect(dis->hDC, &texttarget);
    }

    int oldBkMode = SetBkMode(dis->hDC, TRANSPARENT);

    if (dis->itemState & ODS_DISABLED) {
        // FIXME! This is how NT 3.51 does it, but Win 3.1 is different
        COLORREF oldTextColor = SetTextColor(dis->hDC, GetSysColor(COLOR_BTNSHADOW));

        DrawText(dis->hDC, textbuf, -1, &texttarget, DT_CENTER);

        SetTextColor(dis->hDC, oldTextColor);
    } else {
        DrawText(dis->hDC, textbuf, -1, &texttarget, DT_CENTER);
    }

    SetBkMode(dis->hDC, oldBkMode);

    ALF_Free(textbuf);
}

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

    ALFButtonPriv *priv = (ALFButtonPriv *)dwRefData;

    if (uMsg == ALF_WM_QUERYSIZE) {
        HDC hdc = GetDC(hwnd);
        HFONT font = (HFONT)SendMessage(hwnd, WM_GETFONT, 0, 0);
        HFONT oldFont = 0;
        if (font)
            oldFont = SelectFont(hdc, font);

        // calc drawtext style
        LONG style = GetWindowLong(hwnd, GWL_STYLE);
        UINT format = DT_LEFT | DT_EXPANDTABS | DT_CALCRECT;
        if ((style & BS_MULTILINE) == 0)
            format |= DT_SINGLELINE;

        RECT r = { 0, 0, 0x7FFFFFFF, 100 };

        TCHAR *textbuf = ALF_Text(hwnd);

        DrawText(hdc, textbuf, -1, &r, format);

        ALF_Free(textbuf);

        int xpadding = ALF_Compat_GetSystemMetricsForDpi(SM_CXEDGE,
            (UINT)priv->dpi) * 2 + 6;
        int ypadding = ALF_Compat_GetSystemMetricsForDpi(SM_CYEDGE,
            (UINT)priv->dpi) * 2 + 4;

        SIZE *pSize = (SIZE*)(void*)lParam;
        if (pSize->cx < r.right - r.left + xpadding) {
            pSize->cx = r.right - r.left + xpadding;
        }
        if (pSize->cy < r.bottom - r.top + ypadding) {
            pSize->cy = r.bottom - r.top + ypadding;
        }
        if (pSize->cx < pSize->cy) {
            pSize->cx = pSize->cy;
        }

        if (font)
            SelectFont(hdc, oldFont);

        ReleaseDC(hwnd, hdc);
    } else if (uMsg == 0x2000 + WM_DRAWITEM) {
        LPDRAWITEMSTRUCT dis = (DRAWITEMSTRUCT *)lParam;

        if (!ALF_Compat_BufferedPaintRenderAnimation(hwnd, dis->hDC)) {
            if (priv->hTheme) {
                // Draw XP style themed button
                int stateid = PBS_NORMAL;

                if (priv->isDefault && IsChild(GetForegroundWindow(), hwnd))
                    stateid = priv->uxIsDefaultAnimating ? PBS_DEFAULTED_ANIMATING : PBS_DEFAULTED;
                if (priv->isHot)
                    stateid = PBS_HOT;
                if (dis->itemState & ODS_SELECTED)
                    stateid = PBS_PRESSED;
                if (dis->itemState & ODS_DISABLED)
                    stateid = PBS_DISABLED;

                if (priv->uxStatePrev == -1) {
                    // initial draw
                    priv->uxStateCurrent = stateid;
                    priv->itemStateCurrent = dis->itemState;

                    if (priv->uxStateCurrent == PBS_DEFAULTED || priv->uxStateCurrent == PBS_DEFAULTED_ANIMATING)
                        priv->uxStateCurrent = PBS_NORMAL;
                }

                priv->uxStatePrev = priv->uxStateCurrent;
                priv->uxStateCurrent = stateid;
                priv->itemStatePrev = priv->itemStateCurrent;
                priv->itemStateCurrent = dis->itemState;

                ALF_Compat_BP_ANIMATIONPARAMS animParams;
                ZeroMemory(&animParams, sizeof(animParams));
                animParams.cbSize = sizeof(animParams);
                animParams.style = ALF_Compat_BPAS_LINEAR;

                if (priv->uxStateCurrent != priv->uxStatePrev) {
                    if ((priv->uxStateCurrent == PBS_DEFAULTED && priv->uxStatePrev == PBS_DEFAULTED_ANIMATING) ||
                         (priv->uxStatePrev == PBS_DEFAULTED && priv->uxStateCurrent == PBS_DEFAULTED_ANIMATING)) {
                        animParams.dwDuration = priv->uxDefaultAnimationDuration;
                    } else if (priv->uxStateCurrent == PBS_DEFAULTED_ANIMATING) {
                        // Win7 misses these transition times, use the one for PBS_DEFAULTED
                        ALF_Compat_GetThemeTransitionDuration(priv->hTheme,
                                                              BP_PUSHBUTTON,
                                                              priv->uxStatePrev,
                                                              PBS_DEFAULTED,
                                                              TMT_TRANSITIONDURATION,
                                                              &animParams.dwDuration);
                    } else if (priv->uxStatePrev == PBS_DEFAULTED_ANIMATING) {
                        // Win7 misses these transition times, use the one for PBS_DEFAULTED
                        ALF_Compat_GetThemeTransitionDuration(priv->hTheme,
                                                              BP_PUSHBUTTON,
                                                              PBS_DEFAULTED,
                                                              priv->uxStateCurrent,
                                                              TMT_TRANSITIONDURATION,
                                                              &animParams.dwDuration);
                    } else {
                        ALF_Compat_GetThemeTransitionDuration(priv->hTheme,
                                                              BP_PUSHBUTTON,
                                                              priv->uxStatePrev,
                                                              priv->uxStateCurrent,
                                                              TMT_TRANSITIONDURATION,
                                                              &animParams.dwDuration);
                    }

                    if ((priv->uxStatePrev == PBS_DEFAULTED || priv->uxStatePrev == PBS_DEFAULTED_ANIMATING)
                         && !(priv->uxStateCurrent == PBS_DEFAULTED || priv->uxStateCurrent == PBS_DEFAULTED_ANIMATING)) {
                        KillTimer(hwnd, (UINT_PTR)priv);
                        priv->uxIsDefaultAnimating = FALSE;
                    }

                    if (!(priv->uxStatePrev == PBS_DEFAULTED || priv->uxStatePrev == PBS_DEFAULTED_ANIMATING)
                         && (priv->uxStateCurrent == PBS_DEFAULTED || priv->uxStateCurrent == PBS_DEFAULTED_ANIMATING)
                         && priv->uxDefaultAnimationDuration) {
                        SetTimer(hwnd, (UINT_PTR)priv, priv->uxDefaultAnimationDuration, ALF__Button_DefaultAnimatingTimerProc);
                    }
                }

                HDC hdcFrom = NULL, hdcTo = NULL;
                ALF_Compat_HANIMATIONBUFFER hbpAnimation;

                hbpAnimation = ALF_Compat_BeginBufferedAnimation(hwnd, dis->hDC, &dis->rcItem, 0, NULL, &animParams, &hdcFrom, &hdcTo);
                if (hbpAnimation) {
                    HFONT font = (HFONT)GetCurrentObject(dis->hDC, OBJ_FONT);

                    if (hdcFrom) {
                        SelectFont(hdcFrom, font);
                        ALF__Button_RenderUxtheme(hwnd, priv, priv->uxStatePrev, priv->itemStatePrev, hdcFrom, &dis->rcItem);
                    }

                    if (hdcTo) {
                        SelectFont(hdcTo, font);
                        ALF__Button_RenderUxtheme(hwnd, priv, priv->uxStateCurrent, priv->itemStateCurrent, hdcTo, &dis->rcItem);
                    }

                    ALF_Compat_EndBufferedAnimation(hbpAnimation, TRUE);
                } else {
                    ALF__Button_RenderUxtheme(hwnd, priv, stateid, dis->itemState, dis->hDC, &dis->rcItem);
                }
            } else if (ALF_Compat_IsMinWindowsVersion(4, 0)) {
                // Draw 95 style button
                ALF__Button_Render95(hwnd, priv, dis);
            } else {
                // Draw pre-95 style button
                ALF__Button_Render3x(hwnd, priv, dis);
            }
        }

        return TRUE;
    } else if (uMsg == WM_GETDLGCODE) {
        if (priv->isDefault) {
            return DLGC_DEFPUSHBUTTON | DLGC_BUTTON;
        } else {
            return DLGC_UNDEFPUSHBUTTON | DLGC_BUTTON;
        }
    } else if (uMsg == BM_SETSTYLE) {
        // HACK! stop windows from resetting the owner draw flag
        priv->isDefault = (wParam & BS_DEFPUSHBUTTON) ? 1 : 0;

        return ALF_Compat_DefSubclassProc(hwnd, BM_SETSTYLE, (wParam & 0xFFFFFFF0) | BS_OWNERDRAW, lParam);
    } else if (uMsg == WM_THEMECHANGED) {
        ALF_Compat_CloseThemeData(priv->hTheme);
        priv->hTheme = NULL;
        if (ALF_Compat_IsAppThemed())
            priv->hTheme = ALF_Compat_OpenThemeData(hwnd, L"Button");
        priv->uxDefaultAnimationDuration = 0;
        ALF_Compat_GetThemeTransitionDuration(priv->hTheme,
                                              BP_PUSHBUTTON,
                                              PBS_DEFAULTED,
                                              PBS_DEFAULTED_ANIMATING,
                                              TMT_TRANSITIONDURATION,
                                              &priv->uxDefaultAnimationDuration);
        InvalidateRect(hwnd, NULL, TRUE);
    } else if (uMsg == WM_MOUSEMOVE) {
        if (!priv->isHot) {
            TRACKMOUSEEVENT tme;
            ZeroMemory(&tme, sizeof(tme));
            tme.cbSize = sizeof(tme);
            tme.dwFlags = TME_LEAVE;
            tme.hwndTrack = hwnd;
            if (ALF_Compat_TrackMouseEvent(&tme)) {
                priv->isHot = TRUE;
                InvalidateRect(hwnd, NULL, FALSE);
            }
        }
    } else if (uMsg == WM_MOUSELEAVE) {
        if (priv->isHot) {
            priv->isHot = FALSE;
            InvalidateRect(hwnd, NULL, FALSE);
        }
    } else if (uMsg == WM_DESTROY) {
        ALF_Compat_CloseThemeData(priv->hTheme);
        ALF_Free(priv);
        ALF_Compat_RemoveWindowSubclass(hwnd, ALF__ButtonSubclassProc, 0);
    } else if (uMsg == WM_ERASEBKGND) {
        return TRUE;
    } else if (uMsg == WM_SETTEXT) {
        ALF_InvalidateLayout(GetParent(hwnd));
    } else if (uMsg == WM_SETFONT) {
        ALF_InvalidateLayout(GetParent(hwnd));
    } else if (uMsg == ALF_WM_DPICHANGE) {
        priv->dpi = (int)lParam;
        ALF_InvalidateLayout(GetParent(hwnd));
        return TRUE;
    }

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

HWND
ALF_AddButton(HWND win, WORD id, int x, int y, const TCHAR *text)
{
    HWND hwndButton  = CreateWindowEx(0,
                                      TEXT("BUTTON"),
                                      text,
                                      WS_CHILD | WS_TABSTOP | WS_VISIBLE | BS_PUSHBUTTON | BS_MULTILINE | BS_OWNERDRAW,
                                      0, 0, 100, 100,
                                      win,
                                      (HMENU)(int)id,
                                      (HINSTANCE)GetWindowLongPtr(win, GWLP_HINSTANCE),
                                      NULL);

    ALFButtonPriv *priv = ALF_New(ALFButtonPriv, 1);
    priv->uxStateCurrent = -1;
    priv->uxStatePrev = -1;
    priv->dpi = 96;

    ALF_Compat_SetWindowSubclass(hwndButton, ALF__ButtonSubclassProc, 0, (DWORD_PTR)priv);

    SendMessage(hwndButton, WM_THEMECHANGED, 0, 0);

    ALF_AddWidget(win, x, y, hwndButton, 0, 0, ALF_LAYOUT_SIZE_QUERY | ALF_LAYOUT_INHERITFONT | ALF_LAYOUT_SENDDPICHANGE);

    return hwndButton;
}


void
ALF_SetDefaultButton(HWND win, WORD id)
{
    SendMessage(win, DM_SETDEFID, (WPARAM)id, 0);
}