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#include "qnswindow.h"
#include "qnswindowdelegate.h"
#include "qcocoawindow.h"
#include "qcocoahelpers.h"
#include "qcocoaeventdispatcher.h"

#include <qpa/qwindowsysteminterface.h>
#include <qoperatingsystemversion.h>

static bool isMouseEvent(NSEvent *ev)
{
    switch ([ev type]) {
    case NSLeftMouseDown:
    case NSLeftMouseUp:
    case NSRightMouseDown:
    case NSRightMouseUp:
    case NSMouseMoved:
    case NSLeftMouseDragged:
    case NSRightMouseDragged:
        return true;
    default:
        return false;
    }
}

@implementation NSWindow (FullScreenProperty)

+ (void)load
{
    NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
    [center addObserverForName:NSWindowDidEnterFullScreenNotification object:nil queue:nil
        usingBlock:^(NSNotification *notification) {
            objc_setAssociatedObject(notification.object, @selector(qt_fullScreen),
                [NSNumber numberWithBool:YES], OBJC_ASSOCIATION_RETAIN);
        }
    ];
    [center addObserverForName:NSWindowDidExitFullScreenNotification object:nil queue:nil
        usingBlock:^(NSNotification *notification) {
            objc_setAssociatedObject(notification.object, @selector(qt_fullScreen),
                nil, OBJC_ASSOCIATION_RETAIN);
        }
    ];
}

- (BOOL)qt_fullScreen
{
    NSNumber *number = objc_getAssociatedObject(self, @selector(qt_fullScreen));
    return [number boolValue];
}
@end

#define super USE_qt_objcDynamicSuper_INSTEAD

@implementation QNSWindow

+ (void)load
{
    const Class windowClass = [self class];
    const Class panelClass = [QNSPanel class];

    unsigned int methodDescriptionsCount;
    objc_method_description *methods = protocol_copyMethodDescriptionList(
        objc_getProtocol("QNSWindowProtocol"), NO, YES, &methodDescriptionsCount);

    for (unsigned int i = 0; i < methodDescriptionsCount; ++i) {
        objc_method_description method = methods[i];
        class_addMethod(panelClass, method.name,
            class_getMethodImplementation(windowClass, method.name),
            method.types);
    }

    free(methods);
}

- (QCocoaWindow *)platformWindow
{
    return qnsview_cast(self.contentView).platformWindow;
}

- (BOOL)canBecomeKeyWindow
{
    QCocoaWindow *pw = self.platformWindow;
    if (!pw)
        return NO;

    if (pw->shouldRefuseKeyWindowAndFirstResponder())
        return NO;

    if ([self isKindOfClass:[QNSPanel class]]) {
        // Only tool or dialog windows should become key:
        Qt::WindowType type = pw->window()->type();
        if (type == Qt::Tool || type == Qt::Dialog)
            return YES;

        return NO;
    } else {
        // The default implementation returns NO for title-bar less windows,
        // override and return yes here to make sure popup windows such as
        // the combobox popup can become the key window.
        return YES;
    }
}

- (BOOL)canBecomeMainWindow
{
    BOOL canBecomeMain = YES; // By default, windows can become the main window

    // Windows with a transient parent (such as combobox popup windows)
    // cannot become the main window:
    QCocoaWindow *pw = self.platformWindow;
    if (!pw || pw->window()->transientParent())
        canBecomeMain = NO;

    return canBecomeMain;
}

- (BOOL)isOpaque
{
    return self.platformWindow ?
        self.platformWindow->isOpaque() : qt_objcDynamicSuper();
}

/*!
    Borderless windows need a transparent background

    Technically windows with NSTexturedBackgroundWindowMask (such
    as windows with unified toolbars) need to draw the textured
    background of the NSWindow, and can't have a transparent
    background, but as NSBorderlessWindowMask is 0, you can't
    have a window with NSTexturedBackgroundWindowMask that is
    also borderless.
*/
- (NSColor *)backgroundColor
{
    return self.styleMask == NSBorderlessWindowMask
        ? [NSColor clearColor] : qt_objcDynamicSuper();
}

- (void)sendEvent:(NSEvent*)theEvent
{
    // We might get events for a NSWindow after the corresponding platform
    // window has been deleted, as the NSWindow can outlive the QCocoaWindow
    // e.g. if being retained by other parts of AppKit, or in an auto-release
    // pool. We guard against this in QNSView as well, as not all callbacks
    // come via events, but if they do there's no point in propagating them.
    if (!self.platformWindow)
        return;

    const char *eventType = object_getClassName(theEvent);
    if (QWindowSystemInterface::handleNativeEvent(self.platformWindow->window(),
        QByteArray::fromRawData(eventType, qstrlen(eventType)), theEvent, nullptr)) {
        return;
    }

    qt_objcDynamicSuper(theEvent);

    if (!self.platformWindow)
        return; // Platform window went away while processing event

    QCocoaWindow *pw = self.platformWindow;
    if (pw->frameStrutEventsEnabled() && isMouseEvent(theEvent)) {
        NSPoint loc = [theEvent locationInWindow];
        NSRect windowFrame = [self convertRectFromScreen:self.frame];
        NSRect contentFrame = self.contentView.frame;
        if (NSMouseInRect(loc, windowFrame, NO) && !NSMouseInRect(loc, contentFrame, NO))
            [qnsview_cast(pw->view()) handleFrameStrutMouseEvent:theEvent];
    }
}

- (void)closeAndRelease
{
    qCDebug(lcQpaCocoaWindow) << "closeAndRelease" << self;

    [self.delegate release];
    self.delegate = nil;

    [self close];
    [self release];
}

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wobjc-missing-super-calls"
- (void)dealloc
{
    qt_objcDynamicSuper();
}
#pragma clang diagnostic pop

+ (void)applicationActivationChanged:(NSNotification*)notification
{
    const id sender = self;
    NSEnumerator<NSWindow*> *windowEnumerator = nullptr;
    NSApplication *application = [NSApplication sharedApplication];

#if QT_MACOS_PLATFORM_SDK_EQUAL_OR_ABOVE(__MAC_10_12)
    if (QOperatingSystemVersion::current() >= QOperatingSystemVersion::MacOSSierra) {
        // Unfortunately there's no NSWindowListOrderedBackToFront,
        // so we have to manually reverse the order using an array.
        NSMutableArray *windows = [[[NSMutableArray alloc] init] autorelease];
        [application enumerateWindowsWithOptions:NSWindowListOrderedFrontToBack
            usingBlock:^(NSWindow *window, BOOL *) {
                // For some reason AppKit will give us nil-windows, skip those
                if (!window)
                    return;

                [(NSMutableArray*)windows addObject:window];
            }
        ];

        windowEnumerator = windows.reverseObjectEnumerator;
    } else
#endif
    {
        // No way to get ordered list of windows, so fall back to unordered,
        // list, which typically corresponds to window creation order.
        windowEnumerator = application.windows.objectEnumerator;
    }

    for (NSWindow *window in windowEnumerator) {
        // We're meddling with normal and floating windows, so leave others alone
        if (!(window.level == NSNormalWindowLevel || window.level == NSFloatingWindowLevel))
            continue;

        // Windows that hide automatically will keep their NSFloatingWindowLevel,
        // and hence be on top of the window stack. We don't want to affect these
        // windows, as otherwise we might end up with key windows being ordered
        // behind these auto-hidden windows when activating the application by
        // clicking on a new tool window.
        if (window.hidesOnDeactivate)
            continue;

        if ([window conformsToProtocol:@protocol(QNSWindowProtocol)]) {
            QCocoaWindow *cocoaWindow = static_cast<QCocoaNSWindow *>(window).platformWindow;
            window.level = notification.name == NSApplicationWillResignActiveNotification ?
                NSNormalWindowLevel : cocoaWindow->windowLevel(cocoaWindow->window()->flags());
        }

        // The documentation says that "when a window enters a new level, it’s ordered
        // in front of all its peers in that level", but that doesn't seem to be the
        // case in practice. To keep the order correct after meddling with the window
        // levels, we explicitly order each window to the front. Since we are iterating
        // the windows in back-to-front order, this is okey. The call also triggers AppKit
        // to re-evaluate the level in relation to windows from other applications,
        // working around an issue where our tool windows would stay on top of other
        // application windows if activation was transferred to another application by
        // clicking on it instead of via the application switcher or Dock. Finally, we
        // do this re-ordering for all windows (except auto-hiding ones), otherwise we would
        // end up triggering a bug in AppKit where the tool windows would disappear behind
        // the application window.
        [window orderFront:sender];
    }
}

@end

@implementation QNSPanel
// Implementation shared with QNSWindow, see +[QNSWindow load] above
@end

#undef super