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#include "qiosglobal.h"
#include "qioswindow.h"
#include "qioscontext.h"
#include "qiosinputcontext.h"
#include "qiosscreen.h"
#include "qiosapplicationdelegate.h"
#include "qiosviewcontroller.h"
#include "qiosintegration.h"
#include <QtGui/private/qguiapplication_p.h>
#include <qpa/qplatformintegration.h>

#import <QuartzCore/CAEAGLLayer.h>

#include <QtGui/QKeyEvent>
#include <qpa/qwindowsysteminterface.h>

#include <QtDebug>

@interface EAGLView : UIView <UIKeyInput>
{
@public
    UITextAutocapitalizationType autocapitalizationType;
    UITextAutocorrectionType autocorrectionType;
    BOOL enablesReturnKeyAutomatically;
    UIKeyboardAppearance keyboardAppearance;
    UIKeyboardType keyboardType;
    UIReturnKeyType returnKeyType;
    BOOL secureTextEntry;
    QIOSWindow *m_qioswindow;
    QHash<UITouch *, QWindowSystemInterface::TouchPoint> m_activeTouches;
    int m_nextTouchId;
}

@property(nonatomic) UITextAutocapitalizationType autocapitalizationType;
@property(nonatomic) UITextAutocorrectionType autocorrectionType;
@property(nonatomic) BOOL enablesReturnKeyAutomatically;
@property(nonatomic) UIKeyboardAppearance keyboardAppearance;
@property(nonatomic) UIKeyboardType keyboardType;
@property(nonatomic) UIReturnKeyType returnKeyType;
@property(nonatomic, getter=isSecureTextEntry) BOOL secureTextEntry;

@end

@implementation EAGLView

+ (Class)layerClass
{
    return [CAEAGLLayer class];
}

-(id)initWithQIOSWindow:(QIOSWindow *)window
{
    if (self = [self initWithFrame:toCGRect(window->geometry())])
        m_qioswindow = window;

    return self;
}

- (id)initWithFrame:(CGRect)frame
{
    if ((self = [super initWithFrame:frame])) {
        // Set up EAGL layer
        CAEAGLLayer *eaglLayer = static_cast<CAEAGLLayer *>(self.layer);
        eaglLayer.opaque = TRUE;
        eaglLayer.drawableProperties = [NSDictionary dictionaryWithObjectsAndKeys:
            [NSNumber numberWithBool:YES], kEAGLDrawablePropertyRetainedBacking,
            kEAGLColorFormatRGBA8, kEAGLDrawablePropertyColorFormat, nil];

        // Set up text input
        autocapitalizationType = UITextAutocapitalizationTypeNone;
        autocorrectionType = UITextAutocorrectionTypeNo;
        enablesReturnKeyAutomatically = NO;
        keyboardAppearance = UIKeyboardAppearanceDefault;
        keyboardType = UIKeyboardTypeDefault;
        returnKeyType = UIReturnKeyDone;
        secureTextEntry = NO;
        m_nextTouchId = 0;

        if (isQtApplication())
            self.hidden = YES;

        self.multipleTouchEnabled = YES;
    }

    return self;
}

- (void)layoutSubviews
{
    // This method is the de facto way to know that view has been resized,
    // or otherwise needs invalidation of its buffers. Note though that we
    // do not get this callback when the view just changes its position, so
    // the position of our QWindow (and platform window) will only get updated
    // when the size is also changed.

    if (!CGAffineTransformIsIdentity(self.transform))
        qWarning() << m_qioswindow->window()
            << "is backed by a UIView that has a transform set. This is not supported.";

    QRect geometry = fromCGRect(self.frame);
    m_qioswindow->QPlatformWindow::setGeometry(geometry);
    QWindowSystemInterface::handleGeometryChange(m_qioswindow->window(), geometry);

    // If we have a new size here we need to resize the FBO's corresponding buffers,
    // but we defer that to when the application calls makeCurrent.

    [super layoutSubviews];
}

- (void)updateTouchList:(NSSet *)touches withState:(Qt::TouchPointState)state
{
    // We deliver touch events with global coordinates. But global in this respect means
    // the coordinate system where this QWindow lives. And that is our superview.
    CGSize parentSize = self.superview.frame.size;
    foreach (UITouch *uiTouch, m_activeTouches.keys()) {
        QWindowSystemInterface::TouchPoint &touchPoint = m_activeTouches[uiTouch];
        if (![touches containsObject:uiTouch]) {
            touchPoint.state = Qt::TouchPointStationary;
        } else {
            touchPoint.state = state;
            touchPoint.pressure = (state == Qt::TouchPointReleased) ? 0.0 : 1.0;
            QPoint touchPos = fromCGPoint([uiTouch locationInView:self.superview]);
            touchPoint.area = QRectF(touchPos, QSize(0, 0));
            touchPoint.normalPosition = QPointF(touchPos.x() / parentSize.width, touchPos.y() / parentSize.height);
        }
    }
}

- (void) sendTouchEventWithTimestamp:(ulong)timeStamp
{
    // Send touch event synchronously
    QIOSIntegration *iosIntegration = static_cast<QIOSIntegration *>(QGuiApplicationPrivate::platformIntegration());
    QWindowSystemInterface::handleTouchEvent(m_qioswindow->window(), timeStamp, iosIntegration->touchDevice(), m_activeTouches.values());
    QWindowSystemInterface::flushWindowSystemEvents();
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    // UIKit generates [Began -> Moved -> Ended] event sequences for
    // each touch point. Internally we keep a hashmap of active UITouch
    // points to QWindowSystemInterface::TouchPoints, and assigns each TouchPoint
    // an id for use by Qt.
    for (UITouch *touch in touches) {
        Q_ASSERT(!m_activeTouches.contains(touch));
        m_activeTouches[touch].id = m_nextTouchId++;
    }

    [self updateTouchList:touches withState:Qt::TouchPointPressed];
    [self sendTouchEventWithTimestamp:ulong(event.timestamp * 1000)];
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    [self updateTouchList:touches withState:Qt::TouchPointMoved];
    [self sendTouchEventWithTimestamp:ulong(event.timestamp * 1000)];
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
    QWindow *window = m_qioswindow->window();
    if (window != QGuiApplication::focusWindow() && m_activeTouches.size() == 1) {
        // Activate the touched window if the last touch was released inside it:
        UITouch *touch = static_cast<UITouch *>([[touches allObjects] lastObject]);
        if (CGRectContainsPoint([self bounds], [touch locationInView:self]))
            m_qioswindow->requestActivateWindow();
    }

    [self updateTouchList:touches withState:Qt::TouchPointReleased];
    [self sendTouchEventWithTimestamp:ulong(event.timestamp * 1000)];

    // Remove ended touch points from the active set:
    for (UITouch *touch in touches)
        m_activeTouches.remove(touch);
    if (m_activeTouches.isEmpty())
        m_nextTouchId = 0;
}

- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
    Q_UNUSED(touches) // ### can a subset of the active touches be cancelled?

    // Clear current touch points
    m_activeTouches.clear();
    m_nextTouchId = 0;

    // Send cancel touch event synchronously
    QIOSIntegration *iosIntegration = static_cast<QIOSIntegration *>(QGuiApplicationPrivate::platformIntegration());
    QWindowSystemInterface::handleTouchCancelEvent(m_qioswindow->window(), ulong(event.timestamp * 1000), iosIntegration->touchDevice());
    QWindowSystemInterface::flushWindowSystemEvents();
}

@synthesize autocapitalizationType;
@synthesize autocorrectionType;
@synthesize enablesReturnKeyAutomatically;
@synthesize keyboardAppearance;
@synthesize keyboardType;
@synthesize returnKeyType;
@synthesize secureTextEntry;

- (BOOL)canBecomeFirstResponder
{
    return YES;
}

- (BOOL)becomeFirstResponder
{
    // On iOS, a QWindow should only have input focus when the input panel is
    // open. This is to stop cursors and focus rects from being drawn when the
    // user cannot type. And since the keyboard will open when a view becomes
    // the first responder, it's now a good time to inform QPA that the QWindow
    // this view backs became active:
    QWindowSystemInterface::handleWindowActivated(m_qioswindow->window());
    return [super becomeFirstResponder];
}

- (BOOL)resignFirstResponder
{
    QWindowSystemInterface::handleWindowActivated(0);
    return [super resignFirstResponder];
}

- (BOOL)hasText
{
    return YES;
}

- (void)insertText:(NSString *)text
{
    QString string = QString::fromUtf8([text UTF8String]);
    int key = 0;
    if ([text isEqualToString:@"\n"])
        key = (int)Qt::Key_Return;

    // Send key event to window system interface
    QWindowSystemInterface::handleKeyEvent(
        0, QEvent::KeyPress, key, Qt::NoModifier, string, false, int(string.length()));
    QWindowSystemInterface::handleKeyEvent(
        0, QEvent::KeyRelease, key, Qt::NoModifier, string, false, int(string.length()));
}

- (void)deleteBackward
{
    // Send key event to window system interface
    QWindowSystemInterface::handleKeyEvent(
        0, QEvent::KeyPress, (int)Qt::Key_Backspace, Qt::NoModifier);
    QWindowSystemInterface::handleKeyEvent(
        0, QEvent::KeyRelease, (int)Qt::Key_Backspace, Qt::NoModifier);
}

@end

@implementation UIView (QIOS)

- (QWindow *)qwindow
{
    if ([self isKindOfClass:[EAGLView class]])
        return static_cast<EAGLView *>(self)->m_qioswindow->window();
    return nil;
}

@end

QT_BEGIN_NAMESPACE

QIOSWindow::QIOSWindow(QWindow *window)
    : QPlatformWindow(window)
    , m_view([[EAGLView alloc] initWithQIOSWindow:this])
    , m_requestedGeometry(QPlatformWindow::geometry())
    , m_windowLevel(0)
    , m_devicePixelRatio(1.0)
{
    setParent(parent());
    setWindowState(window->windowState());

    // Retina support: get screen scale factor and set it in the content view.
    // This will make framebufferObject() create a 2x frame buffer on retina
    // displays. Also set m_devicePixelRatio which is used for scaling the
    // paint device.
    if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)] == YES) {
        m_devicePixelRatio = [[UIScreen mainScreen] scale];
        [m_view setContentScaleFactor: m_devicePixelRatio];
    }
}

QIOSWindow::~QIOSWindow()
{
    [m_view removeFromSuperview];
    [m_view release];
}

bool QIOSWindow::blockedByModal()
{
    QWindow *modalWindow = QGuiApplication::modalWindow();
    return modalWindow && modalWindow != window();
}

void QIOSWindow::setVisible(bool visible)
{
    QPlatformWindow::setVisible(visible);
    m_view.hidden = !visible;

    if (!isQtApplication())
        return;

    // Since iOS doesn't do window management the way a Qt application
    // expects, we need to raise and activate windows ourselves:
    if (visible)
        updateWindowLevel();

    if (blockedByModal()) {
        if (visible)
            raise();
        return;
    }

    if (visible) {
        requestActivateWindow();
    } else {
        // Activate top-most visible QWindow:
        NSArray *subviews = qiosViewController().view.subviews;
        for (int i = int(subviews.count) - 1; i >= 0; --i) {
            UIView *view = [subviews objectAtIndex:i];
            if (!view.hidden) {
                if (QWindow *window = view.qwindow) {
                    static_cast<QIOSWindow *>(window->handle())->requestActivateWindow();
                    break;
                }
            }
        }
    }
}

void QIOSWindow::setGeometry(const QRect &rect)
{
    // If the window is in fullscreen, just bookkeep the requested
    // geometry in case the window goes into Qt::WindowNoState later:
    m_requestedGeometry = rect;
    if (window()->windowState() & (Qt::WindowMaximized | Qt::WindowFullScreen))
        return;

    // Since we don't support transformations on the UIView, we can set the frame
    // directly and let UIKit deal with translating that into bounds and center.
    // Changing the size of the view will end up in a call to -[EAGLView layoutSubviews]
    // which will update QWindowSystemInterface with the new size.
    m_view.frame = toCGRect(rect);
}

void QIOSWindow::setWindowState(Qt::WindowState state)
{
    // FIXME: Figure out where or how we should disable/enable the statusbar.
    // Perhaps setting QWindow to maximized should also mean that we'll show
    // the statusbar, and vice versa for fullscreen?

    switch (state) {
    case Qt::WindowMaximized:
    case Qt::WindowFullScreen: {
        // Since UIScreen does not take orientation into account when
        // reporting geometry, we need to look at the top view instead:
        CGSize fullscreenSize = m_view.window.rootViewController.view.bounds.size;
        m_view.frame = CGRectMake(0, 0, fullscreenSize.width, fullscreenSize.height);
        m_view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
        break; }
    default:
        m_view.frame = toCGRect(m_requestedGeometry);
        m_view.autoresizingMask = UIViewAutoresizingNone;
        break;
    }
}

void QIOSWindow::setParent(const QPlatformWindow *parentWindow)
{
    if (parentWindow) {
        UIView *parentView = reinterpret_cast<UIView *>(parentWindow->winId());
        [parentView addSubview:m_view];
    } else if (isQtApplication()) {
        [qiosViewController().view addSubview:m_view];
    }
}

void QIOSWindow::requestActivateWindow()
{
    // Note that several windows can be active at the same time if they exist in the same
    // hierarchy (transient children). But only one window can be QGuiApplication::focusWindow().
    // Dispite the name, 'requestActivateWindow' means raise and transfer focus to the window:
    if (!window()->isTopLevel() || blockedByModal())
        return;

    raise();
    QPlatformInputContext *context = QGuiApplicationPrivate::platformIntegration()->inputContext();
    static_cast<QIOSInputContext *>(context)->focusViewChanged(m_view);
}

void QIOSWindow::raiseOrLower(bool raise)
{
    // Re-insert m_view at the correct index among its sibling views
    // (QWindows) according to their current m_windowLevel:
    if (!isQtApplication())
        return;

    NSArray *subviews = m_view.superview.subviews;
    if (subviews.count == 1)
        return;

    for (int i = int(subviews.count) - 1; i >= 0; --i) {
        UIView *view = static_cast<UIView *>([subviews objectAtIndex:i]);
        if (view.hidden || view == m_view)
            continue;
        int level = static_cast<QIOSWindow *>(view.qwindow->handle())->m_windowLevel;
        if (m_windowLevel > level || (raise && m_windowLevel == level)) {
            [m_view.superview insertSubview:m_view aboveSubview:view];
            return;
        }
    }
    [m_view.superview insertSubview:m_view atIndex:0];
}

void QIOSWindow::updateWindowLevel()
{
    Qt::WindowType type = windowType();

    if (type == Qt::ToolTip)
        m_windowLevel = 120;
    else if (window()->flags() & Qt::WindowStaysOnTopHint)
        m_windowLevel = 100;
    else if (window()->isModal())
        m_windowLevel = 40;
    else if (type == Qt::Popup)
        m_windowLevel = 30;
    else if (type == Qt::SplashScreen)
        m_windowLevel = 20;
    else if (type == Qt::Tool)
        m_windowLevel = 10;
    else
        m_windowLevel = 0;

    // A window should be in at least the same m_windowLevel as its parent:
    QWindow *transientParent = window()->transientParent();
    QIOSWindow *transientParentWindow = transientParent ? static_cast<QIOSWindow *>(transientParent->handle()) : 0;
    if (transientParentWindow)
        m_windowLevel = qMax(transientParentWindow->m_windowLevel, m_windowLevel);
}

void QIOSWindow::handleContentOrientationChange(Qt::ScreenOrientation orientation)
{
    // Keep the status bar in sync with content orientation. This will ensure
    // that the task bar (and associated gestures) are aligned correctly:
    UIInterfaceOrientation uiOrientation = UIInterfaceOrientation(fromQtScreenOrientation(orientation));
    [[UIApplication sharedApplication] setStatusBarOrientation:uiOrientation animated:NO];
}

qreal QIOSWindow::devicePixelRatio() const
{
    return m_devicePixelRatio;
}

int QIOSWindow::effectiveWidth() const
{
    return geometry().width() * m_devicePixelRatio;
}

int QIOSWindow::effectiveHeight() const
{
    return geometry().height() * m_devicePixelRatio;
}

QT_END_NAMESPACE