Pluginize the platform styles

This enforces decoupling and in the case of QMacStyle, isolates
QtWidgets and therefore end user applications, from Carbon/HITheme.

Windows and Fusion are platform independent, so they remain built-in
(but mostly because the Windows style is tightly coupled to other styles
like QStylesheetStyle).

Task-number: QTBUG-59428
Change-Id: Id6519fe0c5269c1bce5b5921f9db06257032a1c9
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@qt.io>

1 files changed, 341 insertions, 0 deletions

diff --git a/src/plugins/styles/windowsvista/qwindowsxpstyle_p_p.h b/src/plugins/styles/windowsvista/qwindowsxpstyle_p_p.h
new file mode 100644
index 0000000000..721a734829
--- /dev/null
+++ b/src/plugins/styles/windowsvista/qwindowsxpstyle_p_p.h
@@ -0,0 +1,341 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWidgets module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QWINDOWSXPSTYLE_P_P_H
+#define QWINDOWSXPSTYLE_P_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists for the convenience
+// of qapplication_*.cpp, qwidget*.cpp and qfiledialog.cpp.  This header
+// file may change from version to version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtWidgets/private/qtwidgetsglobal_p.h>
+#include "qwindowsxpstyle_p.h"
+#include <QtWidgets/private/qwindowsstyle_p_p.h>
+#include <qmap.h>
+#include <qt_windows.h>
+
+#include <uxtheme.h>
+#include <vssym32.h>
+
+#include <limits.h>
+
+QT_BEGIN_NAMESPACE
+
+// TMT_TEXTSHADOWCOLOR is wrongly defined in mingw
+#if TMT_TEXTSHADOWCOLOR != 3818
+#undef TMT_TEXTSHADOWCOLOR
+#define TMT_TEXTSHADOWCOLOR 3818
+#endif
+#ifndef TST_NONE
+#  define TST_NONE 0
+#endif
+
+// These defines are missing from the tmschema, but still exist as
+// states for their parts
+#ifndef MINBS_INACTIVE
+#define MINBS_INACTIVE 5
+#endif
+#ifndef MAXBS_INACTIVE
+#define MAXBS_INACTIVE 5
+#endif
+#ifndef RBS_INACTIVE
+#define RBS_INACTIVE 5
+#endif
+#ifndef HBS_INACTIVE
+#define HBS_INACTIVE 5
+#endif
+#ifndef CBS_INACTIVE
+#define CBS_INACTIVE 5
+#endif
+
+// Uncomment define below to build debug assisting code, and output
+// #define DEBUG_XP_STYLE
+
+// Declarations -----------------------------------------------------------------------------------
+class XPThemeData
+{
+public:
+    explicit XPThemeData(const QWidget *w = 0, QPainter *p = 0, int themeIn = -1,
+                         int part = 0, int state = 0, const QRect &r = QRect())
+        : widget(w), painter(p), theme(themeIn), htheme(0), partId(part), stateId(state),
+          mirrorHorizontally(false), mirrorVertically(false), noBorder(false),
+          noContent(false), rotate(0), rect(r)
+    {}
+
+    HRGN mask(QWidget *widget);
+    HTHEME handle();
+
+    static RECT toRECT(const QRect &qr);
+    bool isValid();
+
+    QSizeF size();
+    QMarginsF margins(const QRect &rect, int propId = TMT_CONTENTMARGINS);
+    QMarginsF margins(int propId = TMT_CONTENTMARGINS);
+
+    static QSizeF themeSize(const QWidget *w = 0, QPainter *p = 0, int themeIn = -1, int part = 0, int state = 0);
+    static QMarginsF themeMargins(const QRect &rect, const QWidget *w = 0, QPainter *p = 0, int themeIn = -1,
+                                  int part = 0, int state = 0, int propId = TMT_CONTENTMARGINS);
+    static QMarginsF themeMargins(const QWidget *w = 0, QPainter *p = 0, int themeIn = -1,
+                                  int part = 0, int state = 0, int propId = TMT_CONTENTMARGINS);
+
+    const QWidget *widget;
+    QPainter *painter;
+
+    int theme;
+    HTHEME htheme;
+    int partId;
+    int stateId;
+
+    uint mirrorHorizontally : 1;
+    uint mirrorVertically : 1;
+    uint noBorder : 1;
+    uint noContent : 1;
+    uint rotate;
+    QRect rect;
+};
+
+struct ThemeMapKey {
+    int theme;
+    int partId;
+    int stateId;
+    bool noBorder;
+    bool noContent;
+
+    ThemeMapKey() : partId(-1), stateId(-1) {}
+    ThemeMapKey(const XPThemeData &data)
+        : theme(data.theme), partId(data.partId), stateId(data.stateId),
+        noBorder(data.noBorder), noContent(data.noContent) {}
+
+};
+
+inline uint qHash(const ThemeMapKey &key)
+{ return key.theme ^ key.partId ^ key.stateId; }
+
+inline bool operator==(const ThemeMapKey &k1, const ThemeMapKey &k2)
+{
+    return k1.theme == k2.theme
+           && k1.partId == k2.partId
+           && k1.stateId == k2.stateId;
+}
+
+enum AlphaChannelType {
+    UnknownAlpha = -1,          // Alpha of part & state not yet known
+    NoAlpha,                    // Totally opaque, no need to touch alpha (RGB)
+    MaskAlpha,                  // Alpha channel must be fixed            (ARGB)
+    RealAlpha                   // Proper alpha values from Windows       (ARGB_Premultiplied)
+};
+
+struct ThemeMapData {
+    AlphaChannelType alphaType; // Which type of alpha on part & state
+
+    bool dataValid         : 1; // Only used to detect if hash value is ok
+    bool partIsTransparent : 1;
+    bool hasAlphaChannel   : 1; // True =  part & state has real Alpha
+    bool wasAlphaSwapped   : 1; // True =  alpha channel needs to be swapped
+    bool hadInvalidAlpha   : 1; // True =  alpha channel contained invalid alpha values
+
+    ThemeMapData() : dataValid(false), partIsTransparent(false),
+                     hasAlphaChannel(false), wasAlphaSwapped(false), hadInvalidAlpha(false) {}
+};
+
+class QWindowsXPStylePrivate : public QWindowsStylePrivate
+{
+    Q_DECLARE_PUBLIC(QWindowsXPStyle)
+public:
+    enum Theme {
+        ButtonTheme,
+        ComboboxTheme,
+        EditTheme,
+        HeaderTheme,
+        ListViewTheme,
+        MenuTheme,
+        ProgressTheme,
+        RebarTheme,
+        ScrollBarTheme,
+        SpinTheme,
+        TabTheme,
+        TaskDialogTheme,
+        ToolBarTheme,
+        ToolTipTheme,
+        TrackBarTheme,
+        XpTreeViewTheme, // '+'/'-' shape treeview indicators (XP)
+        WindowTheme,
+        StatusTheme,
+        VistaTreeViewTheme, // arrow shape treeview indicators (Vista) obtained from "explorer" theme.
+        NThemes
+    };
+
+    QWindowsXPStylePrivate()
+        : QWindowsStylePrivate(), hasInitColors(false), bufferDC(0), bufferBitmap(0), nullBitmap(0),
+          bufferPixels(0), bufferW(0), bufferH(0)
+    { init(); }
+
+    ~QWindowsXPStylePrivate()
+    { cleanup(); }
+
+    static int pixelMetricFromSystemDp(QStyle::PixelMetric pm, const QStyleOption *option = 0, const QWidget *widget = 0);
+    static int fixedPixelMetric(QStyle::PixelMetric pm, const QStyleOption *option = 0, const QWidget *widget = 0);
+
+    static HWND winId(const QWidget *widget);
+
+    void init(bool force = false);
+    void cleanup(bool force = false);
+    void cleanupHandleMap();
+    const QPixmap *tabBody(QWidget *widget);
+
+    HBITMAP buffer(int w = 0, int h = 0);
+    HDC bufferHDC()
+    { return bufferDC;}
+
+    static bool useXP(bool update = false);
+    static QRect scrollBarGripperBounds(QStyle::State flags, const QWidget *widget, XPThemeData *theme);
+
+    bool isTransparent(XPThemeData &themeData);
+    QRegion region(XPThemeData &themeData);
+
+    void setTransparency(QWidget *widget, XPThemeData &themeData);
+    bool drawBackground(XPThemeData &themeData);
+    bool drawBackgroundThruNativeBuffer(XPThemeData &themeData, qreal aditionalDevicePixelRatio);
+    bool drawBackgroundDirectly(HDC dc, XPThemeData &themeData, qreal aditionalDevicePixelRatio);
+
+    bool hasAlphaChannel(const QRect &rect);
+    bool fixAlphaChannel(const QRect &rect);
+    bool swapAlphaChannel(const QRect &rect, bool allPixels = false);
+
+    QRgb groupBoxTextColor;
+    QRgb groupBoxTextColorDisabled;
+    QRgb sliderTickColor;
+    bool hasInitColors;
+
+    static HTHEME createTheme(int theme, HWND hwnd);
+    static QString themeName(int theme);
+    static inline bool hasTheme(int theme) { return theme >= 0 && theme < NThemes && m_themes[theme]; }
+    static bool isItemViewDelegateLineEdit(const QWidget *widget);
+    static bool isLineEditBaseColorSet(const QStyleOption *option, const QWidget *widget);
+
+    QIcon dockFloat, dockClose;
+
+private:
+#ifdef DEBUG_XP_STYLE
+    void dumpNativeDIB(int w, int h);
+    void showProperties(XPThemeData &themeData);
+#endif
+
+    static bool initVistaTreeViewTheming();
+    static void cleanupVistaTreeViewTheming();
+
+    static QBasicAtomicInt ref;
+    static bool use_xp;
+    static QPixmap *tabbody;
+
+    QHash<ThemeMapKey, ThemeMapData> alphaCache;
+    HDC bufferDC;
+    HBITMAP bufferBitmap;
+    HBITMAP nullBitmap;
+    uchar *bufferPixels;
+    int bufferW, bufferH;
+
+    static HWND m_vistaTreeViewHelper;
+    static HTHEME m_themes[NThemes];
+};
+
+inline QSizeF XPThemeData::size()
+{
+    QSizeF result(0, 0);
+    if (isValid()) {
+        SIZE size;
+        if (SUCCEEDED(GetThemePartSize(handle(), 0, partId, stateId, 0, TS_TRUE, &size)))
+            result = QSize(size.cx, size.cy);
+    }
+    return result;
+}
+
+inline QMarginsF XPThemeData::margins(const QRect &qRect, int propId)
+{
+    QMarginsF result(0, 0, 0 ,0);
+    if (isValid()) {
+        MARGINS margins;
+        RECT rect = XPThemeData::toRECT(qRect);
+        if (SUCCEEDED(GetThemeMargins(handle(), 0, partId, stateId, propId, &rect, &margins)))
+            result = QMargins(margins.cxLeftWidth, margins.cyTopHeight, margins.cxRightWidth, margins.cyBottomHeight);
+    }
+    return result;
+}
+
+inline QMarginsF XPThemeData::margins(int propId)
+{
+    QMarginsF result(0, 0, 0 ,0);
+    if (isValid()) {
+        MARGINS margins;
+        if (SUCCEEDED(GetThemeMargins(handle(), 0, partId, stateId, propId, NULL, &margins)))
+            result = QMargins(margins.cxLeftWidth, margins.cyTopHeight, margins.cxRightWidth, margins.cyBottomHeight);
+    }
+    return result;
+}
+
+inline QSizeF XPThemeData::themeSize(const QWidget *w, QPainter *p, int themeIn, int part, int state)
+{
+    XPThemeData theme(w, p, themeIn, part, state);
+    return theme.size();
+}
+
+inline QMarginsF XPThemeData::themeMargins(const QRect &rect, const QWidget *w, QPainter *p, int themeIn,
+                                           int part, int state, int propId)
+{
+    XPThemeData theme(w, p, themeIn, part, state);
+    return theme.margins(rect, propId);
+}
+
+inline QMarginsF XPThemeData::themeMargins(const QWidget *w, QPainter *p, int themeIn,
+                                           int part, int state, int propId)
+{
+    XPThemeData theme(w, p, themeIn, part, state);
+    return theme.margins(propId);
+}
+
+QT_END_NAMESPACE
+
+#endif //QWINDOWSXPSTYLE_P_P_H