/****************************************************************************
**
** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the QtOpenGL 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 Digia.  For licensing terms and
** conditions see http://qt.digia.com/licensing.  For further information
** use the contact form at http://qt.digia.com/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 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Digia gives you certain additional
** rights.  These rights are described in the Digia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef QGL_P_H
#define QGL_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists for the convenience
// of the QGLWidget class.  This header file may change from
// version to version without notice, or even be removed.
//
// We mean it.
//

#include "QtOpenGL/qgl.h"
#include "QtOpenGL/qglcolormap.h"
#include "QtCore/qmap.h"
#include "QtCore/qthread.h"
#include "QtCore/qthreadstorage.h"
#include "QtCore/qhash.h"
#include "private/qwidget_p.h"

#ifndef QT_OPENGL_ES_1_CL
#define q_vertexType float
#define q_vertexTypeEnum GL_FLOAT
#define f2vt(f)     (f)
#define vt2f(x)     (x)
#define i2vt(i)     (float(i))
#else
#define FLOAT2X(f)      (int( (f) * (65536)))
#define X2FLOAT(x)      (float(x) / 65536.0f)
#define f2vt(f)     FLOAT2X(f)
#define i2vt(i)     ((i)*65536)
#define vt2f(x)     X2FLOAT(x)
#define q_vertexType GLfixed
#define q_vertexTypeEnum GL_FIXED
#endif //QT_OPENGL_ES_1_CL

#ifdef QT_OPENGL_ES
QT_BEGIN_INCLUDE_NAMESPACE
#if defined(QT_OPENGL_ES_2)
#include <EGL/egl.h>
#else
#include <GLES/egl.h>
#endif
QT_END_INCLUDE_NAMESPACE
#endif

QT_BEGIN_NAMESPACE

class QGLContext;
class QGLOverlayWidget;
class QPixmap;
class QPixmapFilter;
#ifdef Q_WS_MAC
# ifdef qDebug
#   define old_qDebug qDebug
#   undef qDebug
# endif
QT_BEGIN_INCLUDE_NAMESPACE
#ifndef QT_MAC_USE_COCOA
# include <AGL/agl.h>
#endif
QT_END_INCLUDE_NAMESPACE
# ifdef old_qDebug
#   undef qDebug
#   define qDebug QT_QDEBUG_MACRO
#   undef old_qDebug
# endif
class QMacWindowChangeEvent;
#endif

#ifdef Q_WS_QWS
class QWSGLWindowSurface;
#endif

#if defined(QT_OPENGL_ES)
class QEglContext;
#endif

QT_BEGIN_INCLUDE_NAMESPACE
#include <QtOpenGL/private/qglextensions_p.h>
QT_END_INCLUDE_NAMESPACE

class QGLFormatPrivate
{
public:
    QGLFormatPrivate() {
        opts = QGL::DoubleBuffer | QGL::DepthBuffer | QGL::Rgba | QGL::DirectRendering | QGL::StencilBuffer;
#if defined(QT_OPENGL_ES_2)
        opts |= QGL::SampleBuffers;
#endif
        pln = 0;
        depthSize = accumSize = stencilSize = redSize = greenSize = blueSize = alphaSize = -1;
        numSamples = -1;
        swapInterval = -1;
    }
    QGL::FormatOptions opts;
    int pln;
    int depthSize;
    int accumSize;
    int stencilSize;
    int redSize;
    int greenSize;
    int blueSize;
    int alphaSize;
    int numSamples;
    int swapInterval;
};

class QGLWidgetPrivate : public QWidgetPrivate
{
    Q_DECLARE_PUBLIC(QGLWidget)
public:
    QGLWidgetPrivate() : QWidgetPrivate()
#ifdef Q_WS_QWS
                       , wsurf(0)
#endif
#if defined(Q_WS_X11) && defined(QT_OPENGL_ES)
                       , eglSurfaceWindowId(0)
#endif
    {
        isGLWidget = 1;
    }

    ~QGLWidgetPrivate() {}

    void init(QGLContext *context, const QGLWidget* shareWidget);
    void initContext(QGLContext *context, const QGLWidget* shareWidget);
    bool renderCxPm(QPixmap *pixmap);
    void cleanupColormaps();

    QGLContext *glcx;
    bool autoSwap;

    QGLColormap cmap;
    QMap<QString, int> displayListCache;

#if defined(Q_WS_WIN)
    void updateColormap();
    QGLContext *olcx;
#elif defined(Q_WS_X11)
    QGLOverlayWidget *olw;
#if defined(QT_OPENGL_ES)
    void recreateEglSurface(bool force);
    WId eglSurfaceWindowId;
#endif
#elif defined(Q_WS_MAC)
    QGLContext *olcx;
    void updatePaintDevice();
#elif defined(Q_WS_QWS)
    QWSGLWindowSurface *wsurf;
#endif
};

class QGLContextPrivate
{
    Q_DECLARE_PUBLIC(QGLContext)
public:
    explicit QGLContextPrivate(QGLContext *context) : internal_context(false), q_ptr(context) {}
    ~QGLContextPrivate() {}
    GLuint bindTexture(const QImage &image, GLenum target, GLint format, const qint64 key,
                       bool clean = false);
    GLuint bindTexture(const QPixmap &pixmap, GLenum target, GLint format, bool clean);
    GLuint bindTexture(const QImage &image, GLenum target, GLint format, bool clean);
    bool textureCacheLookup(const qint64 key, GLenum target, GLuint *id);
    void init(QPaintDevice *dev, const QGLFormat &format);
    QImage convertToGLFormat(const QImage &image, bool force_premul, GLenum texture_format);
    int maxTextureSize();

    void cleanup();

#if defined(Q_WS_WIN)
    HGLRC rc;
    HDC dc;
    WId        win;
    int pixelFormatId;
    QGLCmap* cmap;
    HBITMAP hbitmap;
    HDC hbitmap_hdc;
#endif
#if defined(QT_OPENGL_ES)
    QEglContext *eglContext;
#elif defined(Q_WS_X11) || defined(Q_WS_MAC)
    void* cx;
#endif
#if defined(Q_WS_X11) || defined(Q_WS_MAC)
    void* vi;
#endif
#if defined(Q_WS_X11)
    void* pbuf;
    quint32 gpm;
    int screen;
#endif
#if defined(Q_WS_MAC)
    bool update;
    void *tryFormat(const QGLFormat &format);
    void clearDrawable();
#endif
    QGLFormat glFormat;
    QGLFormat reqFormat;
    GLuint pbo;

    uint valid : 1;
    uint sharing : 1;
    uint initDone : 1;
    uint crWin : 1;
    uint clear_on_painter_begin : 1;
    uint internal_context : 1;
    uint version_flags_cached : 1;
    QPaintDevice *paintDevice;
    QColor transpColor;
    QGLContext *q_ptr;
    QGLFormat::OpenGLVersionFlags version_flags;

    QGLExtensionFuncs extensionFuncs;
    GLint max_texture_size;

#ifdef Q_WS_WIN
    static inline QGLExtensionFuncs& qt_get_extension_funcs(const QGLContext *ctx) { return ctx->d_ptr->extensionFuncs; }
#endif

#if defined(Q_WS_X11) || defined(Q_WS_MAC) || defined(Q_WS_QWS)
    static QGLExtensionFuncs qt_extensionFuncs;
    static inline QGLExtensionFuncs& qt_get_extension_funcs(const QGLContext *) { return qt_extensionFuncs; }
#endif

    QPixmapFilter *createPixmapFilter(int type) const;
};

// ### make QGLContext a QObject in 5.0 and remove the proxy stuff
class QGLSignalProxy : public QObject
{
    Q_OBJECT
public:
    QGLSignalProxy() : QObject() {}
    void emitAboutToDestroyContext(const QGLContext *context) {
        emit aboutToDestroyContext(context);
    }
    static QGLSignalProxy *instance();
Q_SIGNALS:
    void aboutToDestroyContext(const QGLContext *context);
};

// GL extension definitions
class QGLExtensions {
public:
    enum Extension {
        TextureRectangle        = 0x00000001,
        SampleBuffers           = 0x00000002,
        GenerateMipmap          = 0x00000004,
        TextureCompression      = 0x00000008,
        FragmentProgram         = 0x00000010,
        MirroredRepeat          = 0x00000020,
        FramebufferObject       = 0x00000040,
        StencilTwoSide          = 0x00000080,
        StencilWrap             = 0x00000100,
        PackedDepthStencil      = 0x00000200,
        NVFloatBuffer           = 0x00000400,
        PixelBufferObject       = 0x00000800
    };
    Q_DECLARE_FLAGS(Extensions, Extension)

    static Extensions glExtensions;
    static bool nvidiaFboNeedsFinish;
    static void init(); // sys dependent
    static void init_extensions(); // general: called by init()
};

Q_DECLARE_OPERATORS_FOR_FLAGS(QGLExtensions::Extensions)


struct QGLThreadContext {
    QGLContext *context;
};
extern QThreadStorage<QGLThreadContext *> qgl_context_storage;

typedef QMultiHash<const QGLContext *, const QGLContext *> QGLSharingHash;
class QGLShareRegister
{
public:
    QGLShareRegister() {}
    ~QGLShareRegister() { reg.clear(); }

    bool checkSharing(const QGLContext *context1, const QGLContext *context2, const QGLContext * skip=0) {
        if (context1 == context2)
            return true;
        QList<const QGLContext *> shares = reg.values(context1);
        for (int k=0; k<shares.size(); ++k) {
            const QGLContext *ctx = shares.at(k);
            if (ctx == skip) // avoid an indirect circular loop (infinite recursion)
                continue;
            if (ctx == context2)
                return true;
            if (checkSharing(ctx, context2, context1))
                return true;
        }
        return false;
    }

    void addShare(const QGLContext *context, const QGLContext *share) {
        reg.insert(context, share); // context sharing works both ways
        reg.insert(share, context);
    }

    void removeShare(const QGLContext *context) {
        QGLSharingHash::iterator it = reg.begin();
        while (it != reg.end()) {
            if (it.key() == context || it.value() == context)
                it = reg.erase(it);
            else
                ++it;
        }
    }

    void replaceShare(const QGLContext *oldContext, const QGLContext *newContext) {
        QGLSharingHash::iterator it = reg.begin();
        while (it != reg.end()) {
            if (it.key() == oldContext)
                reg.insert(newContext, it.value());
            else if (it.value() == oldContext)
                reg.insert(it.key(), newContext);
            ++it;
        }
        removeShare(oldContext);
    }

private:
    QGLSharingHash reg;
};

extern Q_OPENGL_EXPORT QGLShareRegister* qgl_share_reg();

#ifdef Q_WS_QWS
class QOpenGLPaintEngine;
extern QOpenGLPaintEngine* qt_qgl_paint_engine();

extern EGLDisplay qt_qgl_egl_display();
#endif

inline GLenum qt_gl_preferredTextureFormat()
{
    return QSysInfo::ByteOrder == QSysInfo::BigEndian ? GL_RGBA : GL_BGRA;
}

inline GLenum qt_gl_preferredTextureTarget()
{
    return (QGLExtensions::glExtensions & QGLExtensions::TextureRectangle)
           ? GL_TEXTURE_RECTANGLE_NV
           : GL_TEXTURE_2D;
}


QT_END_NAMESPACE

#endif // QGL_P_H