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#include "qeglfswindow.h"
#include "qeglfshooks.h"
#include "qeglfscursor.h"
#include "qeglfsbackingstore.h"
#include <qpa/qwindowsysteminterface.h>
#include <qpa/qplatformintegration.h>
#include <private/qguiapplication_p.h>
#include <QtGui/QOpenGLContext>

#include <QtPlatformSupport/private/qeglconvenience_p.h>

#include <QtDebug>

QT_BEGIN_NAMESPACE

QEglFSWindow::QEglFSWindow(QWindow *w)
    : QPlatformWindow(w)
    , m_surface(0)
    , m_window(0)
    , m_wid(0)
    , m_backingStore(0)
    , m_flags(0)
{
#ifdef QEGL_EXTRA_DEBUG
    qWarning("QEglWindow %p: %p 0x%x\n", this, w, uint(m_window));
#endif
}

QEglFSWindow::~QEglFSWindow()
{
    destroy();
}

static WId newWId()
{
    static WId id = 0;

    if (id == std::numeric_limits<WId>::max())
        qWarning("EGLFS: Out of window IDs");

    return ++id;
}

void QEglFSWindow::create()
{
    if (m_flags.testFlag(Created))
        return;

    m_flags = Created;
    m_wid = newWId();

    if (window()->type() == Qt::Desktop) {
        QRect rect(QPoint(), QEglFSHooks::hooks()->screenSize());
        QPlatformWindow::setGeometry(rect);
        QWindowSystemInterface::handleGeometryChange(window(), rect);
        return;
    }

    // Save the original surface type before changing to OpenGLSurface.
    if (window()->surfaceType() == QSurface::RasterSurface)
        m_flags |= IsRaster;

    // Stop if there is already a window backed by a native window and surface. Additional
    // raster windows will not have their own native window, surface and context. Instead,
    // they will be composited onto the root window's surface.
    QEglFSScreen *screen = this->screen();
    if (screen->primarySurface() != EGL_NO_SURFACE) {
        if (m_flags.testFlag(IsRaster) && screen->rootWindow()->m_flags.testFlag(IsRaster))
            return;

#if !defined(Q_OS_ANDROID) || defined(Q_OS_ANDROID_NO_SDK)
        // We can have either a single OpenGL window or multiple raster windows.
        // Other combinations cannot work.
        qFatal("EGLFS: OpenGL windows cannot be mixed with others.");
#endif

        return;
    }

    window()->setSurfaceType(QSurface::OpenGLSurface);
    m_flags |= HasNativeWindow;
    setGeometry(QRect()); // will become fullscreen
    QWindowSystemInterface::handleExposeEvent(window(), geometry());

    EGLDisplay display = static_cast<QEglFSScreen *>(screen)->display();
    QSurfaceFormat platformFormat = QEglFSHooks::hooks()->surfaceFormatFor(window()->requestedFormat());
    m_config = QEglFSIntegration::chooseConfig(display, platformFormat);
    m_format = q_glFormatFromConfig(display, m_config);

    resetSurface();

    screen->setPrimarySurface(m_surface);

    if (m_flags.testFlag(IsRaster)) {
        QOpenGLContext *context = new QOpenGLContext(QGuiApplication::instance());
        context->setFormat(window()->requestedFormat());
        context->setScreen(window()->screen());
        context->create();
        screen->setRootContext(context);
    }
}

void QEglFSWindow::destroy()
{
    QEglFSScreen *screen = this->screen();
    if (m_flags.testFlag(HasNativeWindow)) {
        QEglFSCursor *cursor = static_cast<QEglFSCursor *>(screen->cursor());
        if (cursor)
            cursor->resetResources();

        if (screen->primarySurface() == m_surface)
            screen->setPrimarySurface(EGL_NO_SURFACE);

        invalidateSurface();
    }

    m_flags = 0;
    screen->removeWindow(this);
}

// The virtual functions resetSurface and invalidateSurface may get overridden
// in derived classes, for example in the Android port, to perform the native
// window and surface creation differently.

void QEglFSWindow::invalidateSurface()
{
    if (m_surface != EGL_NO_SURFACE) {
        EGLDisplay display = static_cast<QEglFSScreen *>(screen())->display();
        eglDestroySurface(display, m_surface);
        m_surface = EGL_NO_SURFACE;
    }
    QEglFSHooks::hooks()->destroyNativeWindow(m_window);
    m_window = 0;
}

void QEglFSWindow::resetSurface()
{
    EGLDisplay display = static_cast<QEglFSScreen *>(screen())->display();
    m_window = QEglFSHooks::hooks()->createNativeWindow(this, QEglFSHooks::hooks()->screenSize(), m_format);
    m_surface = eglCreateWindowSurface(display, m_config, m_window, NULL);
    if (m_surface == EGL_NO_SURFACE) {
        EGLint error = eglGetError();
        eglTerminate(display);
        qFatal("EGL Error : Could not create the egl surface: error = 0x%x\n", error);
    }
}

void QEglFSWindow::setVisible(bool visible)
{
    QList<QEglFSWindow *> windows = screen()->windows();

    if (window()->type() != Qt::Desktop) {
        if (visible) {
            screen()->addWindow(this);
        } else {
            screen()->removeWindow(this);
            windows = screen()->windows();
            if (windows.size())
                windows.last()->requestActivateWindow();
        }
    }

    QWindowSystemInterface::handleExposeEvent(window(), window()->geometry());

    if (visible)
        QWindowSystemInterface::flushWindowSystemEvents();
}

void QEglFSWindow::setGeometry(const QRect &r)
{
    QRect rect;
    if (m_flags.testFlag(HasNativeWindow))
        rect = screen()->availableGeometry();
    else
        rect = r;

    QPlatformWindow::setGeometry(rect);

    if (rect != r)
        QWindowSystemInterface::handleGeometryChange(window(), rect);
}

QRect QEglFSWindow::geometry() const
{
    // For yet-to-become-fullscreen windows report the geometry covering the entire
    // screen. This is particularly important for Quick where the root object may get
    // sized to some geometry queried before calling create().
    if (!m_flags.testFlag(Created) && screen()->primarySurface() == EGL_NO_SURFACE)
        return screen()->availableGeometry();

    return QPlatformWindow::geometry();
}

WId QEglFSWindow::winId() const
{
    return m_wid;
}

void QEglFSWindow::requestActivateWindow()
{
    if (window()->type() != Qt::Desktop)
        screen()->moveToTop(this);

    QWindowSystemInterface::handleWindowActivated(window());
    QWindowSystemInterface::handleExposeEvent(window(), window()->geometry());
}

void QEglFSWindow::raise()
{
    if (window()->type() != Qt::Desktop) {
        screen()->moveToTop(this);
        QWindowSystemInterface::handleExposeEvent(window(), window()->geometry());
    }
}

void QEglFSWindow::lower()
{
    QList<QEglFSWindow *> windows = screen()->windows();
    if (window()->type() != Qt::Desktop && windows.count() > 1) {
        int idx = windows.indexOf(this);
        if (idx > 0) {
            screen()->changeWindowIndex(this, idx - 1);
            QWindowSystemInterface::handleExposeEvent(windows.last()->window(), windows.last()->geometry());
        }
    }
}

EGLSurface QEglFSWindow::surface() const
{
    return m_surface != EGL_NO_SURFACE ? m_surface : screen()->primarySurface();
}

QSurfaceFormat QEglFSWindow::format() const
{
    return m_format;
}

EGLNativeWindowType QEglFSWindow::eglWindow() const
{
    return m_window;
}

QEglFSScreen *QEglFSWindow::screen() const
{
    return static_cast<QEglFSScreen *>(QPlatformWindow::screen());
}

uint QEglFSWindow::texture() const
{
    if (m_backingStore)
        return m_backingStore->texture();

    return 0;
}

QT_END_NAMESPACE