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#include <QtGui/qpaintdevice.h>

#include <QtGui/qpixmap.h>

#include <QtGui/qwidget.h>

#include <QtCore/qdebug.h>

#include "qegl_p.h"

#include "qeglcontext_p.h"

QT_BEGIN_NAMESPACE

// Current GL and VG contexts.  These are used to determine if

// we can avoid an eglMakeCurrent() after a call to lazyDoneCurrent().

// If a background thread modifies the value, the worst that will

// happen is a redundant eglMakeCurrent() in the foreground thread.

static QEglContext * volatile currentGLContext = 0;

static QEglContext * volatile currentVGContext = 0;

QEglContext::QEglContext()

    : apiType(QEgl::OpenGL)

    , ctx(EGL_NO_CONTEXT)

    , cfg(QEGL_NO_CONFIG)

    , currentSurface(EGL_NO_SURFACE)

    , current(false)

    , ownsContext(true)

    , sharing(false)

{

}

QEglContext::~QEglContext()

{

    destroyContext();

    if (currentGLContext == this)

        currentGLContext = 0;

    if (currentVGContext == this)

        currentVGContext = 0;

}

bool QEglContext::isValid() const

{

    return (ctx != EGL_NO_CONTEXT);

}

bool QEglContext::isCurrent() const

{

    return current;

}

EGLConfig QEgl::defaultConfig(int devType, API api, ConfigOptions options)

{

    if ( (devType != QInternal::Pixmap) && ((options & Renderable) == 0))

        qWarning("QEgl::defaultConfig() - Only configs for pixmaps make sense to be read-only!");

    EGLConfig* targetConfig = 0;

    static EGLConfig defaultVGConfigs[] = {

        QEGL_NO_CONFIG, // 0    Window  Renderable  Translucent

        QEGL_NO_CONFIG, // 1    Window  Renderable  Opaque

        QEGL_NO_CONFIG, // 2    Pixmap  Renderable  Translucent

        QEGL_NO_CONFIG, // 3    Pixmap  Renderable  Opaque

        QEGL_NO_CONFIG, // 4    Pixmap  ReadOnly    Translucent

        QEGL_NO_CONFIG  // 5    Pixmap  ReadOnly    Opaque

    };

    if (api == OpenVG) {

        if (devType == QInternal::Widget) {

            if (options & Translucent)

                targetConfig = &(defaultVGConfigs[0]);

            else

                targetConfig = &(defaultVGConfigs[1]);

        } else if (devType == QInternal::Pixmap) {

            if (options & Renderable) {

                if (options & Translucent)

                    targetConfig = &(defaultVGConfigs[2]);

                else // Opaque

                    targetConfig = &(defaultVGConfigs[3]);

            } else { // Read-only

                if (options & Translucent)

                    targetConfig = &(defaultVGConfigs[4]);

                else // Opaque

                    targetConfig = &(defaultVGConfigs[5]);

            }

        }

    }

    static EGLConfig defaultGLConfigs[] = {

        QEGL_NO_CONFIG, // 0    Window  Renderable  Translucent

        QEGL_NO_CONFIG, // 1    Window  Renderable  Opaque

        QEGL_NO_CONFIG, // 2    PBuffer Renderable  Translucent

        QEGL_NO_CONFIG, // 3    PBuffer Renderable  Opaque

        QEGL_NO_CONFIG, // 4    Pixmap  Renderable  Translucent

        QEGL_NO_CONFIG, // 5    Pixmap  Renderable  Opaque

        QEGL_NO_CONFIG, // 6    Pixmap  ReadOnly    Translucent

        QEGL_NO_CONFIG  // 7    Pixmap  ReadOnly    Opaque

    };

    if (api == OpenGL) {

        if (devType == QInternal::Widget) {

            if (options & Translucent)

                targetConfig = &(defaultGLConfigs[0]);

            else // Opaque

                targetConfig = &(defaultGLConfigs[1]);

        } else if (devType == QInternal::Pbuffer) {

            if (options & Translucent)

                targetConfig = &(defaultGLConfigs[2]);

            else // Opaque

                targetConfig = &(defaultGLConfigs[3]);

        } else if (devType == QInternal::Pixmap) {

            if (options & Renderable) {

                if (options & Translucent)

                    targetConfig = &(defaultGLConfigs[4]);

                else // Opaque

                    targetConfig = &(defaultGLConfigs[5]);

            } else { // ReadOnly

                if (options & Translucent)

                    targetConfig = &(defaultGLConfigs[6]);

                else // Opaque

                    targetConfig = &(defaultGLConfigs[7]);

            }

        }

    }

    if (!targetConfig) {

        qWarning("QEgl::defaultConfig() - No default config for device/api/options combo");

        return QEGL_NO_CONFIG;

    }

    if (*targetConfig != QEGL_NO_CONFIG)

        return *targetConfig;

    // We haven't found an EGL config for the target config yet, so do it now:

    // Allow overriding from an environment variable:

    QByteArray configId;

    if (api == OpenVG)

        configId = qgetenv("QT_VG_EGL_CONFIG");

    else

        configId = qgetenv("QT_GL_EGL_CONFIG");

    if (!configId.isEmpty()) {

        // Overriden, so get the EGLConfig for the specified config ID:

        EGLint properties[] = {

            EGL_CONFIG_ID, (EGLint)configId.toInt(),

            EGL_NONE

        };

        EGLint configCount = 0;

        eglChooseConfig(display(), properties, targetConfig, 1, &configCount);

        if (configCount > 0)

            return *targetConfig;

        qWarning() << "QEgl::defaultConfig() -" << configId << "appears to be invalid";

    }

    QEglProperties configAttribs;

    configAttribs.setRenderableType(api);

    EGLint surfaceType;

    switch (devType) {

        case QInternal::Widget:

            surfaceType = EGL_WINDOW_BIT;

            break;

        case QInternal::Pixmap:

            surfaceType = EGL_PIXMAP_BIT;

            break;

        case QInternal::Pbuffer:

            surfaceType = EGL_PBUFFER_BIT;

            break;

        default:

            qWarning("QEgl::defaultConfig() - Can't create EGL surface for %d device type", devType);

            return QEGL_NO_CONFIG;

    };

#ifdef EGL_VG_ALPHA_FORMAT_PRE_BIT

    // For OpenVG, we try to create a surface using a pre-multiplied format if

    // the surface needs to have an alpha channel:

    if (api == OpenVG && (options & Translucent))

        surfaceType |= EGL_VG_ALPHA_FORMAT_PRE_BIT;

#endif

    configAttribs.setValue(EGL_SURFACE_TYPE, surfaceType);

#ifdef EGL_BIND_TO_TEXTURE_RGBA

    if (devType == QInternal::Pixmap || devType == QInternal::Pbuffer) {

        if (options & Translucent)

            configAttribs.setValue(EGL_BIND_TO_TEXTURE_RGBA, EGL_TRUE);

        else

            configAttribs.setValue(EGL_BIND_TO_TEXTURE_RGB, EGL_TRUE);

    }

#endif

    // Add paint engine requirements

    if (api == OpenVG) {

#ifndef QVG_SCISSOR_CLIP

        configAttribs.setValue(EGL_ALPHA_MASK_SIZE, 1);

#endif

    } else {

        // Both OpenGL paint engines need to have stencil and sample buffers

        configAttribs.setValue(EGL_STENCIL_SIZE, 1);

        configAttribs.setValue(EGL_SAMPLE_BUFFERS, 1);

#ifndef QT_OPENGL_ES_2

        // Aditionally, the GL1 engine likes to have a depth buffer for clipping

        configAttribs.setValue(EGL_DEPTH_SIZE, 1);

#endif

    }

    if (options & Translucent)

        configAttribs.setValue(EGL_ALPHA_SIZE, 1);

    *targetConfig = chooseConfig(&configAttribs, QEgl::BestPixelFormat);

    return *targetConfig;

}

// Choose a configuration that matches "properties".

EGLConfig QEgl::chooseConfig(const QEglProperties* properties, QEgl::PixelFormatMatch match)

{

    QEglProperties props(*properties);

    EGLConfig cfg = QEGL_NO_CONFIG;

    do {

        // Get the number of matching configurations for this set of properties.

        EGLint matching = 0;

        EGLDisplay dpy = QEgl::display();

        if (!eglChooseConfig(dpy, props.properties(), 0, 0, &matching) || !matching)

            continue;

        // If we want the best pixel format, then return the first

        // matching configuration.

        if (match == QEgl::BestPixelFormat) {

            eglChooseConfig(display(), props.properties(), &cfg, 1, &matching);

            if (matching < 1)

                continue;

            return cfg;

        }

        // Fetch all of the matching configurations and find the

        // first that matches the pixel format we wanted.

        EGLint size = matching;

        EGLConfig *configs = new EGLConfig [size];

        eglChooseConfig(display(), props.properties(), configs, size, &matching);

        for (EGLint index = 0; index < size; ++index) {

            EGLint red, green, blue, alpha;

            eglGetConfigAttrib(display(), configs[index], EGL_RED_SIZE, &red);

            eglGetConfigAttrib(display(), configs[index], EGL_GREEN_SIZE, &green);

            eglGetConfigAttrib(display(), configs[index], EGL_BLUE_SIZE, &blue);

            eglGetConfigAttrib(display(), configs[index], EGL_ALPHA_SIZE, &alpha);

            if (red == props.value(EGL_RED_SIZE) &&

                    green == props.value(EGL_GREEN_SIZE) &&

                    blue == props.value(EGL_BLUE_SIZE) &&

                    (props.value(EGL_ALPHA_SIZE) == 0 ||

                     alpha == props.value(EGL_ALPHA_SIZE))) {

                cfg = configs[index];

                delete [] configs;

                return cfg;

            }

        }

        delete [] configs;

    } while (props.reduceConfiguration());

#ifdef EGL_BIND_TO_TEXTURE_RGBA

    // Don't report an error just yet if we failed to get a pbuffer

    // configuration with texture rendering.  Only report failure if

    // we cannot get any pbuffer configurations at all.

    if (props.value(EGL_BIND_TO_TEXTURE_RGBA) == EGL_DONT_CARE &&

        props.value(EGL_BIND_TO_TEXTURE_RGB) == EGL_DONT_CARE)

#endif

    {

        qWarning() << "QEglContext::chooseConfig(): Could not find a suitable EGL configuration";

        qWarning() << "Requested:" << props.toString();

        qWarning() << "Available:";

        QEgl::dumpAllConfigs();

    }

    return QEGL_NO_CONFIG;

}

bool QEglContext::chooseConfig(const QEglProperties& properties, QEgl::PixelFormatMatch match)

{

    cfg = QEgl::chooseConfig(&properties, match);

    return cfg != QEGL_NO_CONFIG;

}

EGLSurface QEglContext::createSurface(QPaintDevice* device, const QEglProperties *properties)

{

    return QEgl::createSurface(device, cfg, properties);

}

// Create the EGLContext.

bool QEglContext::createContext(QEglContext *shareContext, const QEglProperties *properties)

{

    // We need to select the correct API before calling eglCreateContext().

#ifdef QT_OPENGL_ES

#ifdef EGL_OPENGL_ES_API

    if (apiType == QEgl::OpenGL)

        eglBindAPI(EGL_OPENGL_ES_API);

#endif

#else

#ifdef EGL_OPENGL_API

    if (apiType == QEgl::OpenGL)

        eglBindAPI(EGL_OPENGL_API);

#endif

#endif //defined(QT_OPENGL_ES)

#ifdef EGL_OPENVG_API

    if (apiType == QEgl::OpenVG)

        eglBindAPI(EGL_OPENVG_API);

#endif

    // Create a new context for the configuration.

    QEglProperties contextProps;

    if (properties)

        contextProps = *properties;

#ifdef QT_OPENGL_ES_2

    if (apiType == QEgl::OpenGL)

        contextProps.setValue(EGL_CONTEXT_CLIENT_VERSION, 2);

#endif

    sharing = false;

    if (shareContext && shareContext->ctx == EGL_NO_CONTEXT)

        shareContext = 0;

    if (shareContext) {

        ctx = eglCreateContext(QEgl::display(), cfg, shareContext->ctx, contextProps.properties());

        if (ctx == EGL_NO_CONTEXT) {

            qWarning() << "QEglContext::createContext(): Could not share context:" << QEgl::errorString();

            shareContext = 0;

        } else {

            sharing = true;

        }

    }

    if (ctx == EGL_NO_CONTEXT) {

        ctx = eglCreateContext(display(), cfg, 0, contextProps.properties());

        if (ctx == EGL_NO_CONTEXT) {

            qWarning() << "QEglContext::createContext(): Unable to create EGL context:" << QEgl::errorString();

            return false;

        }

    }

    return true;

}

// Destroy an EGL surface object.  If it was current on this context

// then call doneCurrent() for it first.

void QEglContext::destroySurface(EGLSurface surface)

{

    if (surface != EGL_NO_SURFACE) {

        if (surface == currentSurface)

            doneCurrent();

        eglDestroySurface(display(), surface);

    }

}

// Destroy the context.  Note: this does not destroy the surface.

void QEglContext::destroyContext()

{

    if (ctx != EGL_NO_CONTEXT && ownsContext)

        eglDestroyContext(display(), ctx);

    ctx = EGL_NO_CONTEXT;

    cfg = 0;

}

bool QEglContext::makeCurrent(EGLSurface surface)

{

    if (ctx == EGL_NO_CONTEXT) {

        qWarning() << "QEglContext::makeCurrent(): Cannot make invalid context current";

        return false;

    }

    if (surface == EGL_NO_SURFACE) {

        qWarning() << "QEglContext::makeCurrent(): Cannot make invalid surface current";

        return false;

    }

    // If lazyDoneCurrent() was called on the surface, then we may be able

    // to assume that it is still current within the thread.

    if (surface == currentSurface && currentContext(apiType) == this) {

        current = true;

        return true;

    }

    current = true;

    currentSurface = surface;

    setCurrentContext(apiType, this);

    // Force the right API to be bound before making the context current.

    // The EGL implementation should be able to figure this out from ctx,

    // but some systems require the API to be explicitly set anyway.

#ifdef EGL_OPENGL_ES_API

    if (apiType == QEgl::OpenGL)

        eglBindAPI(EGL_OPENGL_ES_API);

#endif

#ifdef EGL_OPENVG_API

    if (apiType == QEgl::OpenVG)

        eglBindAPI(EGL_OPENVG_API);

#endif

    bool ok = eglMakeCurrent(QEgl::display(), surface, surface, ctx);

    if (!ok)

        qWarning() << "QEglContext::makeCurrent(" << surface << "):" << QEgl::errorString();

    return ok;

}

bool QEglContext::doneCurrent()

{

    // If the context is invalid, we assume that an error was reported

    // when makeCurrent() was called.

    if (ctx == EGL_NO_CONTEXT)

        return false;

    current = false;

    currentSurface = EGL_NO_SURFACE;

    setCurrentContext(apiType, 0);

    // We need to select the correct API before calling eglMakeCurrent()

    // with EGL_NO_CONTEXT because threads can have both OpenGL and OpenVG

    // contexts active at the same time.

#ifdef EGL_OPENGL_ES_API

    if (apiType == QEgl::OpenGL)

        eglBindAPI(EGL_OPENGL_ES_API);

#endif

#ifdef EGL_OPENVG_API

    if (apiType == QEgl::OpenVG)

        eglBindAPI(EGL_OPENVG_API);

#endif

    bool ok = eglMakeCurrent(QEgl::display(), EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);

    if (!ok)

        qWarning() << "QEglContext::doneCurrent():" << QEgl::errorString();

    return ok;

}

// Act as though doneCurrent() was called, but keep the context

// and the surface active for the moment.  This allows makeCurrent()

// to skip a call to eglMakeCurrent() if we are using the same

// surface as the last set of painting operations.  We leave the

// currentContext() pointer as-is for now.

bool QEglContext::lazyDoneCurrent()

{

    current = false;

    return true;

}