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** This file is part of the plugins of the Qt Toolkit.
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** General Public License version 3 as published by the Free Software
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** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
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** 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
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** 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
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****************************************************************************/

#include <qpa/qplatformtheme.h>

#include "qcocoahelpers.h"
#include "qnsview.h"

#include <QtCore>
#include <QtGui>
#include <qpa/qplatformscreen.h>
#include <private/qguiapplication_p.h>
#include <private/qwindow_p.h>
#include <QtGui/private/qcoregraphics_p.h>

#ifndef QT_NO_WIDGETS
#include <QtWidgets/QWidget>
#endif

#include <algorithm>

#include <Carbon/Carbon.h>

QT_BEGIN_NAMESPACE

Q_LOGGING_CATEGORY(lcQpaCocoaWindow, "qt.qpa.cocoa.window");

//
// Conversion Functions
//

QStringList qt_mac_NSArrayToQStringList(void *nsarray)
{
    QStringList result;
    NSArray *array = static_cast<NSArray *>(nsarray);
    for (NSUInteger i=0; i<[array count]; ++i)
        result << QString::fromNSString([array objectAtIndex:i]);
    return result;
}

void *qt_mac_QStringListToNSMutableArrayVoid(const QStringList &list)
{
    NSMutableArray *result = [NSMutableArray arrayWithCapacity:list.size()];
    for (int i=0; i<list.size(); ++i){
        [result addObject:list[i].toNSString()];
    }
    return result;
}

struct dndenum_mapper
{
    NSDragOperation mac_code;
    Qt::DropAction qt_code;
    bool Qt2Mac;
};

static dndenum_mapper dnd_enums[] = {
    { NSDragOperationLink,  Qt::LinkAction, true },
    { NSDragOperationMove,  Qt::MoveAction, true },
    { NSDragOperationCopy,  Qt::CopyAction, true },
    { NSDragOperationGeneric,  Qt::CopyAction, false },
    { NSDragOperationEvery, Qt::ActionMask, false },
    { NSDragOperationNone, Qt::IgnoreAction, false }
};

NSDragOperation qt_mac_mapDropAction(Qt::DropAction action)
{
    for (int i=0; dnd_enums[i].qt_code; i++) {
        if (dnd_enums[i].Qt2Mac && (action & dnd_enums[i].qt_code)) {
            return dnd_enums[i].mac_code;
        }
    }
    return NSDragOperationNone;
}

NSDragOperation qt_mac_mapDropActions(Qt::DropActions actions)
{
    NSDragOperation nsActions = NSDragOperationNone;
    for (int i=0; dnd_enums[i].qt_code; i++) {
        if (dnd_enums[i].Qt2Mac && (actions & dnd_enums[i].qt_code))
            nsActions |= dnd_enums[i].mac_code;
    }
    return nsActions;
}

Qt::DropAction qt_mac_mapNSDragOperation(NSDragOperation nsActions)
{
    Qt::DropAction action = Qt::IgnoreAction;
    for (int i=0; dnd_enums[i].mac_code; i++) {
        if (nsActions & dnd_enums[i].mac_code)
            return dnd_enums[i].qt_code;
    }
    return action;
}

Qt::DropActions qt_mac_mapNSDragOperations(NSDragOperation nsActions)
{
    Qt::DropActions actions = Qt::IgnoreAction;

    for (int i=0; dnd_enums[i].mac_code; i++) {
        if (dnd_enums[i].mac_code == NSDragOperationEvery)
            continue;

        if (nsActions & dnd_enums[i].mac_code)
            actions |= dnd_enums[i].qt_code;
    }
    return actions;
}

/*!
    Returns the view cast to a QNSview if possible.

    If the view is not a QNSView, nil is returned, which is safe to
    send messages to, effectivly making [qnsview_cast(view) message]
    a no-op.

    For extra verbosity and clearer code, please consider checking
    that window()->type() != Qt::ForeignWindow before using this cast.

    Do not use this method soley to check for foreign windows, as
    that will make the code harder to read for people not working
    primarily on macOS, who do not know the difference between the
    NSView and QNSView cases.
*/
QNSView *qnsview_cast(NSView *view)
{
    if (![view isKindOfClass:[QNSView class]]) {
        qCWarning(lcQpaCocoaWindow) << "NSView is not QNSView, consider checking for Qt::ForeignWindow";
        return nil;
    }

    return static_cast<QNSView *>(view);
}

//
// Misc
//

// Sets the activation policy for this process to NSApplicationActivationPolicyRegular,
// unless either LSUIElement or LSBackgroundOnly is set in the Info.plist.
void qt_mac_transformProccessToForegroundApplication()
{
    bool forceTransform = true;
    CFTypeRef value = CFBundleGetValueForInfoDictionaryKey(CFBundleGetMainBundle(),
                                                           CFSTR("LSUIElement"));
    if (value) {
        CFTypeID valueType = CFGetTypeID(value);
        // Officially it's supposed to be a string, a boolean makes sense, so we'll check.
        // A number less so, but OK.
        if (valueType == CFStringGetTypeID())
            forceTransform = !(QString::fromCFString(static_cast<CFStringRef>(value)).toInt());
        else if (valueType == CFBooleanGetTypeID())
            forceTransform = !CFBooleanGetValue(static_cast<CFBooleanRef>(value));
        else if (valueType == CFNumberGetTypeID()) {
            int valueAsInt;
            CFNumberGetValue(static_cast<CFNumberRef>(value), kCFNumberIntType, &valueAsInt);
            forceTransform = !valueAsInt;
        }
    }

    if (forceTransform) {
        value = CFBundleGetValueForInfoDictionaryKey(CFBundleGetMainBundle(),
                                                     CFSTR("LSBackgroundOnly"));
        if (value) {
            CFTypeID valueType = CFGetTypeID(value);
            if (valueType == CFBooleanGetTypeID())
                forceTransform = !CFBooleanGetValue(static_cast<CFBooleanRef>(value));
            else if (valueType == CFStringGetTypeID())
                forceTransform = !(QString::fromCFString(static_cast<CFStringRef>(value)).toInt());
            else if (valueType == CFNumberGetTypeID()) {
                int valueAsInt;
                CFNumberGetValue(static_cast<CFNumberRef>(value), kCFNumberIntType, &valueAsInt);
                forceTransform = !valueAsInt;
            }
        }
    }

    if (forceTransform) {
        [[NSApplication sharedApplication] setActivationPolicy:NSApplicationActivationPolicyRegular];
    }
}

QString qt_mac_applicationName()
{
    QString appName;
    CFTypeRef string = CFBundleGetValueForInfoDictionaryKey(CFBundleGetMainBundle(), CFSTR("CFBundleName"));
    if (string)
        appName = QString::fromCFString(static_cast<CFStringRef>(string));

    if (appName.isEmpty()) {
        QString arg0 = QGuiApplicationPrivate::instance()->appName();
        if (arg0.contains("/")) {
            QStringList parts = arg0.split(QLatin1Char('/'));
            appName = parts.at(parts.count() - 1);
        } else {
            appName = arg0;
        }
    }
    return appName;
}

int qt_mac_mainScreenHeight()
{
    QMacAutoReleasePool pool;
    NSArray *screens = [NSScreen screens];
    if ([screens count] > 0) {
        // The first screen in the screens array is documented
        // to have the (0,0) origin.
        NSRect screenFrame = [[screens objectAtIndex: 0] frame];
        return screenFrame.size.height;
    }
    return 0;
}

int qt_mac_flipYCoordinate(int y)
{
    return qt_mac_mainScreenHeight() - y;
}

qreal qt_mac_flipYCoordinate(qreal y)
{
    return qt_mac_mainScreenHeight() - y;
}

QPointF qt_mac_flipPoint(const NSPoint &p)
{
    return QPointF(p.x, qt_mac_flipYCoordinate(p.y));
}

NSPoint qt_mac_flipPoint(const QPoint &p)
{
    return NSMakePoint(p.x(), qt_mac_flipYCoordinate(p.y()));
}

NSPoint qt_mac_flipPoint(const QPointF &p)
{
    return NSMakePoint(p.x(), qt_mac_flipYCoordinate(p.y()));
}

NSRect qt_mac_flipRect(const QRect &rect)
{
    int flippedY = qt_mac_flipYCoordinate(rect.y() + rect.height());
    return NSMakeRect(rect.x(), flippedY, rect.width(), rect.height());
}

Qt::MouseButton cocoaButton2QtButton(NSInteger buttonNum)
{
    if (buttonNum == 0)
        return Qt::LeftButton;
    if (buttonNum == 1)
        return Qt::RightButton;
    if (buttonNum == 2)
        return Qt::MiddleButton;
    if (buttonNum >= 3 && buttonNum <= 31) { // handle XButton1 and higher via logical shift
        return Qt::MouseButton(uint(Qt::MiddleButton) << (buttonNum - 3));
    }
    // else error: buttonNum too high, or negative
    return Qt::NoButton;
}

QString qt_mac_removeAmpersandEscapes(QString s)
{
    return QPlatformTheme::removeMnemonics(s).trimmed();
}

QT_END_NAMESPACE

/*! \internal

    This NSView derived class is used to add OK/Cancel
    buttons to NSColorPanel and NSFontPanel. It replaces
    the panel's content view, while reparenting the former
    content view into itself. It also takes care of setting
    the target-action for the OK/Cancel buttons and making
    sure the layout is consistent.
 */
@implementation QNSPanelContentsWrapper

- (instancetype)initWithPanelDelegate:(id<QT_MANGLE_NAMESPACE(QNSPanelDelegate)>)panelDelegate
{
    if ((self = [super initWithFrame:NSZeroRect])) {
        // create OK and Cancel buttons and add these as subviews
        _okButton = [self createButtonWithTitle:"&OK"];
        _okButton.action = @selector(onOkClicked);
        _okButton.target = panelDelegate;

        _cancelButton = [self createButtonWithTitle:"Cancel"];
        _cancelButton.action = @selector(onCancelClicked);
        _cancelButton.target = panelDelegate;

        _panelContents = nil;

        _panelContentsMargins = NSEdgeInsetsMake(0, 0, 0, 0);
    }

    return self;
}

- (void)dealloc
{
    [_okButton release];
    _okButton = nil;
    [_cancelButton release];
    _cancelButton = nil;

    _panelContents = nil;

    [super dealloc];
}

- (NSButton *)createButtonWithTitle:(const char *)title
{
    NSButton *button = [[NSButton alloc] initWithFrame:NSZeroRect];
    button.buttonType = NSMomentaryLightButton;
    button.bezelStyle = NSRoundedBezelStyle;
    const QString &cleanTitle = QPlatformTheme::removeMnemonics(QCoreApplication::translate("QDialogButtonBox", title));
    // FIXME: Not obvious, from Cocoa's documentation, that QString::toNSString() makes a deep copy
    button.title = (NSString *)cleanTitle.toCFString();
    ((NSButtonCell *)button.cell).font =
            [NSFont systemFontOfSize:[NSFont systemFontSizeForControlSize:NSRegularControlSize]];
    [self addSubview:button];
    return button;
}

- (void)layout
{
    static const CGFloat ButtonMinWidth = 78.0; // 84.0 for Carbon
    static const CGFloat ButtonMinHeight = 32.0;
    static const CGFloat ButtonSpacing = 0.0;
    static const CGFloat ButtonTopMargin = 0.0;
    static const CGFloat ButtonBottomMargin = 7.0;
    static const CGFloat ButtonSideMargin = 9.0;

    NSSize frameSize = self.frame.size;

    [self.okButton sizeToFit];
    NSSize okSizeHint = self.okButton.frame.size;

    [self.cancelButton sizeToFit];
    NSSize cancelSizeHint = self.cancelButton.frame.size;

    const CGFloat buttonWidth = qMin(qMax(ButtonMinWidth,
                                          qMax(okSizeHint.width, cancelSizeHint.width)),
                                     CGFloat((frameSize.width - 2.0 * ButtonSideMargin - ButtonSpacing) * 0.5));
    const CGFloat buttonHeight = qMax(ButtonMinHeight,
                                     qMax(okSizeHint.height, cancelSizeHint.height));

    NSRect okRect = { { frameSize.width - ButtonSideMargin - buttonWidth,
                        ButtonBottomMargin },
                      { buttonWidth, buttonHeight } };
    self.okButton.frame = okRect;
    self.okButton.needsDisplay = YES;

    NSRect cancelRect = { { okRect.origin.x - ButtonSpacing - buttonWidth,
                            ButtonBottomMargin },
                            { buttonWidth, buttonHeight } };
    self.cancelButton.frame = cancelRect;
    self.cancelButton.needsDisplay = YES;

    // The third view should be the original panel contents. Cache it.
    if (!self.panelContents)
        for (NSView *view in self.subviews)
            if (view != self.okButton && view != self.cancelButton) {
                _panelContents = view;
                break;
            }

    const CGFloat buttonBoxHeight = ButtonBottomMargin + buttonHeight + ButtonTopMargin;
    const NSRect panelContentsFrame = NSMakeRect(
                self.panelContentsMargins.left,
                buttonBoxHeight + self.panelContentsMargins.bottom,
                frameSize.width - (self.panelContentsMargins.left + self.panelContentsMargins.right),
                frameSize.height - buttonBoxHeight - (self.panelContentsMargins.top + self.panelContentsMargins.bottom));
    self.panelContents.frame = panelContentsFrame;
    self.panelContents.needsDisplay = YES;

    self.needsDisplay = YES;
}

@end