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#include "qglengineshadermanager_p.h"

#include "qglengineshadersource_p.h"

#if defined(QT_DEBUG)

#include <QMetaEnum>

#endif

QT_BEGIN_NAMESPACE

static void qt_shared_shaders_free(void *data)

{

    delete reinterpret_cast<QGLEngineSharedShaders *>(data);

}

Q_GLOBAL_STATIC_WITH_ARGS(QGLContextResource, qt_shared_shaders, (qt_shared_shaders_free))

QGLEngineSharedShaders *QGLEngineSharedShaders::shadersForContext(const QGLContext *context)

{

    QGLEngineSharedShaders *p = reinterpret_cast<QGLEngineSharedShaders *>(qt_shared_shaders()->value(context));

    if (!p) {

        QGLShareContextScope scope(context);

        qt_shared_shaders()->insert(context, p = new QGLEngineSharedShaders(context));

    }

    return p;

}

const char* QGLEngineSharedShaders::qShaderSnippets[] = {

    0,0,0,0,0,0,0,0,0,0,

    0,0,0,0,0,0,0,0,0,0,

    0,0,0,0,0,0,0,0,0,0,

    0,0,0,0,0

};

QGLEngineSharedShaders::QGLEngineSharedShaders(const QGLContext* context)

    : ctxGuard(context)

    , blitShaderProg(0)

    , simpleShaderProg(0)

{

/*

    Rather than having the shader source array statically initialised, it is initialised

    here instead. This is to allow new shader names to be inserted or existing names moved

    around without having to change the order of the glsl strings. It is hoped this will

    make future hard-to-find runtime bugs more obvious and generally give more solid code.

*/

    static bool snippetsPopulated = false;

    if (!snippetsPopulated) {

        const char** code = qShaderSnippets; // shortcut

        code[MainVertexShader] = qglslMainVertexShader;

        code[MainWithTexCoordsVertexShader] = qglslMainWithTexCoordsVertexShader;

        code[MainWithTexCoordsAndOpacityVertexShader] = qglslMainWithTexCoordsAndOpacityVertexShader;

        code[UntransformedPositionVertexShader] = qglslUntransformedPositionVertexShader;

        code[PositionOnlyVertexShader] = qglslPositionOnlyVertexShader;

        code[PositionWithPatternBrushVertexShader] = qglslPositionWithPatternBrushVertexShader;

        code[PositionWithLinearGradientBrushVertexShader] = qglslPositionWithLinearGradientBrushVertexShader;

        code[PositionWithConicalGradientBrushVertexShader] = qglslPositionWithConicalGradientBrushVertexShader;

        code[PositionWithRadialGradientBrushVertexShader] = qglslPositionWithRadialGradientBrushVertexShader;

        code[PositionWithTextureBrushVertexShader] = qglslPositionWithTextureBrushVertexShader;

        code[AffinePositionWithPatternBrushVertexShader] = qglslAffinePositionWithPatternBrushVertexShader;

        code[AffinePositionWithLinearGradientBrushVertexShader] = qglslAffinePositionWithLinearGradientBrushVertexShader;

        code[AffinePositionWithConicalGradientBrushVertexShader] = qglslAffinePositionWithConicalGradientBrushVertexShader;

        code[AffinePositionWithRadialGradientBrushVertexShader] = qglslAffinePositionWithRadialGradientBrushVertexShader;

        code[AffinePositionWithTextureBrushVertexShader] = qglslAffinePositionWithTextureBrushVertexShader;

        code[MainFragmentShader_CMO] = qglslMainFragmentShader_CMO;

        code[MainFragmentShader_CM] = qglslMainFragmentShader_CM;

        code[MainFragmentShader_MO] = qglslMainFragmentShader_MO;

        code[MainFragmentShader_M] = qglslMainFragmentShader_M;

        code[MainFragmentShader_CO] = qglslMainFragmentShader_CO;

        code[MainFragmentShader_C] = qglslMainFragmentShader_C;

        code[MainFragmentShader_O] = qglslMainFragmentShader_O;

        code[MainFragmentShader] = qglslMainFragmentShader;

        code[MainFragmentShader_ImageArrays] = qglslMainFragmentShader_ImageArrays;

        code[ImageSrcFragmentShader] = qglslImageSrcFragmentShader;

        code[ImageSrcWithPatternFragmentShader] = qglslImageSrcWithPatternFragmentShader;

        code[NonPremultipliedImageSrcFragmentShader] = qglslNonPremultipliedImageSrcFragmentShader;

        code[CustomImageSrcFragmentShader] = qglslCustomSrcFragmentShader; // Calls "customShader", which must be appended

        code[SolidBrushSrcFragmentShader] = qglslSolidBrushSrcFragmentShader;

        code[TextureBrushSrcFragmentShader] = qglslTextureBrushSrcFragmentShader;

        code[TextureBrushSrcWithPatternFragmentShader] = qglslTextureBrushSrcWithPatternFragmentShader;

        code[PatternBrushSrcFragmentShader] = qglslPatternBrushSrcFragmentShader;

        code[LinearGradientBrushSrcFragmentShader] = qglslLinearGradientBrushSrcFragmentShader;

        code[RadialGradientBrushSrcFragmentShader] = qglslRadialGradientBrushSrcFragmentShader;

        code[ConicalGradientBrushSrcFragmentShader] = qglslConicalGradientBrushSrcFragmentShader;

        code[ShockingPinkSrcFragmentShader] = qglslShockingPinkSrcFragmentShader;

        code[NoMaskFragmentShader] = "";

        code[MaskFragmentShader] = qglslMaskFragmentShader;

        code[RgbMaskFragmentShaderPass1] = qglslRgbMaskFragmentShaderPass1;

        code[RgbMaskFragmentShaderPass2] = qglslRgbMaskFragmentShaderPass2;

        code[RgbMaskWithGammaFragmentShader] = ""; //###

        code[NoCompositionModeFragmentShader] = "";

        code[MultiplyCompositionModeFragmentShader] = ""; //###

        code[ScreenCompositionModeFragmentShader] = ""; //###

        code[OverlayCompositionModeFragmentShader] = ""; //###

        code[DarkenCompositionModeFragmentShader] = ""; //###

        code[LightenCompositionModeFragmentShader] = ""; //###

        code[ColorDodgeCompositionModeFragmentShader] = ""; //###

        code[ColorBurnCompositionModeFragmentShader] = ""; //###

        code[HardLightCompositionModeFragmentShader] = ""; //###

        code[SoftLightCompositionModeFragmentShader] = ""; //###

        code[DifferenceCompositionModeFragmentShader] = ""; //###

        code[ExclusionCompositionModeFragmentShader] = ""; //###

#if defined(QT_DEBUG)

        // Check that all the elements have been filled:

        for (int i = 0; i < TotalSnippetCount; ++i) {

            if (qShaderSnippets[i] == 0) {

                qFatal("Shader snippet for %s (#%d) is missing!",

                       snippetNameStr(SnippetName(i)).constData(), i);

            }

        }

#endif

        snippetsPopulated = true;

    }

    QGLShader* fragShader;

    QGLShader* vertexShader;

    QByteArray source;

    // Compile up the simple shader:

    source.clear();

    source.append(qShaderSnippets[MainVertexShader]);

    source.append(qShaderSnippets[PositionOnlyVertexShader]);

    vertexShader = new QGLShader(QGLShader::Vertex, context, this);

    if (!vertexShader->compileSourceCode(source))

        qWarning("Vertex shader for simpleShaderProg (MainVertexShader & PositionOnlyVertexShader) failed to compile");

    source.clear();

    source.append(qShaderSnippets[MainFragmentShader]);

    source.append(qShaderSnippets[ShockingPinkSrcFragmentShader]);

    fragShader = new QGLShader(QGLShader::Fragment, context, this);

    if (!fragShader->compileSourceCode(source))

        qWarning("Fragment shader for simpleShaderProg (MainFragmentShader & ShockingPinkSrcFragmentShader) failed to compile");

    simpleShaderProg = new QGLShaderProgram(context, this);

    simpleShaderProg->addShader(vertexShader);

    simpleShaderProg->addShader(fragShader);

    simpleShaderProg->bindAttributeLocation("vertexCoordsArray", QT_VERTEX_COORDS_ATTR);

    simpleShaderProg->bindAttributeLocation("pmvMatrix1", QT_PMV_MATRIX_1_ATTR);

    simpleShaderProg->bindAttributeLocation("pmvMatrix2", QT_PMV_MATRIX_2_ATTR);

    simpleShaderProg->bindAttributeLocation("pmvMatrix3", QT_PMV_MATRIX_3_ATTR);

    simpleShaderProg->link();

    if (!simpleShaderProg->isLinked()) {

        qCritical() << "Errors linking simple shader:"

                    << simpleShaderProg->log();

    }

    // Compile the blit shader:

    source.clear();

    source.append(qShaderSnippets[MainWithTexCoordsVertexShader]);

    source.append(qShaderSnippets[UntransformedPositionVertexShader]);

    vertexShader = new QGLShader(QGLShader::Vertex, context, this);

    if (!vertexShader->compileSourceCode(source))

        qWarning("Vertex shader for blitShaderProg (MainWithTexCoordsVertexShader & UntransformedPositionVertexShader) failed to compile");

    source.clear();

    source.append(qShaderSnippets[MainFragmentShader]);

    source.append(qShaderSnippets[ImageSrcFragmentShader]);

    fragShader = new QGLShader(QGLShader::Fragment, context, this);

    if (!fragShader->compileSourceCode(source))

        qWarning("Fragment shader for blitShaderProg (MainFragmentShader & ImageSrcFragmentShader) failed to compile");

    blitShaderProg = new QGLShaderProgram(context, this);

    blitShaderProg->addShader(vertexShader);

    blitShaderProg->addShader(fragShader);

    blitShaderProg->bindAttributeLocation("textureCoordArray", QT_TEXTURE_COORDS_ATTR);

    blitShaderProg->bindAttributeLocation("vertexCoordsArray", QT_VERTEX_COORDS_ATTR);

    blitShaderProg->link();

    if (!blitShaderProg->isLinked()) {

        qCritical() << "Errors linking blit shader:"

                    << simpleShaderProg->log();

    }

}

QGLEngineSharedShaders::~QGLEngineSharedShaders()

{

    QList<QGLEngineShaderProg*>::iterator itr;

    for (itr = cachedPrograms.begin(); itr != cachedPrograms.end(); ++itr)

        delete *itr;

    if (blitShaderProg) {

        delete blitShaderProg;

        blitShaderProg = 0;

    }

    if (simpleShaderProg) {

        delete simpleShaderProg;

        simpleShaderProg = 0;

    }

}

#if defined (QT_DEBUG)

QByteArray QGLEngineSharedShaders::snippetNameStr(SnippetName name)

{

    QMetaEnum m = staticMetaObject.enumerator(staticMetaObject.indexOfEnumerator("SnippetName"));

    return QByteArray(m.valueToKey(name));

}

#endif

// The address returned here will only be valid until next time this function is called.

QGLEngineShaderProg *QGLEngineSharedShaders::findProgramInCache(const QGLEngineShaderProg &prog)

{

    for (int i = 0; i < cachedPrograms.size(); ++i) {

        QGLEngineShaderProg *cachedProg = cachedPrograms[i];

        if (*cachedProg == prog) {

            // Move the program to the top of the list as a poor-man's cache algo

            cachedPrograms.move(i, 0);

            return cachedProg;

        }

    }

    QGLShader *vertexShader = 0;

    QGLShader *fragShader = 0;

    QGLEngineShaderProg *newProg = 0;

    bool success = false;

    do {

        QByteArray source;

        // Insert the custom stage before the srcPixel shader to work around an ATI driver bug

        // where you cannot forward declare a function that takes a sampler as argument.

        if (prog.srcPixelFragShader == CustomImageSrcFragmentShader)

            source.append(prog.customStageSource);

        source.append(qShaderSnippets[prog.mainFragShader]);

        source.append(qShaderSnippets[prog.srcPixelFragShader]);

        if (prog.compositionFragShader)

            source.append(qShaderSnippets[prog.compositionFragShader]);

        if (prog.maskFragShader)

            source.append(qShaderSnippets[prog.maskFragShader]);

        fragShader = new QGLShader(QGLShader::Fragment, ctxGuard.context(), this);

        QByteArray description;

#if defined(QT_DEBUG)

        // Name the shader for easier debugging

        description.append("Fragment shader: main=");

        description.append(snippetNameStr(prog.mainFragShader));

        description.append(", srcPixel=");

        description.append(snippetNameStr(prog.srcPixelFragShader));

        if (prog.compositionFragShader) {

            description.append(", composition=");

            description.append(snippetNameStr(prog.compositionFragShader));

        }

        if (prog.maskFragShader) {

            description.append(", mask=");

            description.append(snippetNameStr(prog.maskFragShader));

        }

        fragShader->setObjectName(QString::fromLatin1(description));

#endif

        if (!fragShader->compileSourceCode(source)) {

            qWarning() << "Warning:" << description << "failed to compile!";

            break;

        }

        source.clear();

        source.append(qShaderSnippets[prog.mainVertexShader]);

        source.append(qShaderSnippets[prog.positionVertexShader]);

        vertexShader = new QGLShader(QGLShader::Vertex, ctxGuard.context(), this);

#if defined(QT_DEBUG)

        // Name the shader for easier debugging

        description.clear();

        description.append("Vertex shader: main=");

        description.append(snippetNameStr(prog.mainVertexShader));

        description.append(", position=");

        description.append(snippetNameStr(prog.positionVertexShader));

        vertexShader->setObjectName(QString::fromLatin1(description));

#endif

        if (!vertexShader->compileSourceCode(source)) {

            qWarning() << "Warning:" << description << "failed to compile!";

            break;

        }

        newProg = new QGLEngineShaderProg(prog);

        // If the shader program's not found in the cache, create it now.

        newProg->program = new QGLShaderProgram(ctxGuard.context(), this);

        newProg->program->addShader(vertexShader);

        newProg->program->addShader(fragShader);

        // We have to bind the vertex attribute names before the program is linked:

        newProg->program->bindAttributeLocation("vertexCoordsArray", QT_VERTEX_COORDS_ATTR);

        if (newProg->useTextureCoords)

            newProg->program->bindAttributeLocation("textureCoordArray", QT_TEXTURE_COORDS_ATTR);

        if (newProg->useOpacityAttribute)

            newProg->program->bindAttributeLocation("opacityArray", QT_OPACITY_ATTR);

            newProg->program->bindAttributeLocation("pmvMatrix1", QT_PMV_MATRIX_1_ATTR);

            newProg->program->bindAttributeLocation("pmvMatrix2", QT_PMV_MATRIX_2_ATTR);

            newProg->program->bindAttributeLocation("pmvMatrix3", QT_PMV_MATRIX_3_ATTR);

        }

        newProg->program->link();

        if (!newProg->program->isLinked()) {

            QLatin1String none("none");

            QLatin1String br("\n");

            QString error;

            error = QLatin1String("Shader program failed to link,")

#if defined(QT_DEBUG)

                + br

                + QLatin1String("  Shaders Used:") + br

                + QLatin1String("    ") + vertexShader->objectName() + QLatin1String(": ") + br

                + QLatin1String(vertexShader->sourceCode()) + br

                + QLatin1String("    ") + fragShader->objectName() + QLatin1String(": ") + br

                + QLatin1String(fragShader->sourceCode()) + br

#endif

                + QLatin1String("  Error Log:\n")

                + QLatin1String("    ") + newProg->program->log();

            qWarning() << error;

            break;

        }

        if (cachedPrograms.count() > 30) {

            // The cache is full, so delete the last 5 programs in the list.

            // These programs will be least used, as a program us bumped to

            // the top of the list when it's used.

            for (int i = 0; i < 5; ++i) {

                delete cachedPrograms.last();

                cachedPrograms.removeLast();

            }

        }

        cachedPrograms.insert(0, newProg);

        success = true;

    } while (false);

    // Clean up everything if we weren't successful

    if (!success) {

        if (newProg) {

            delete newProg; // Also deletes the QGLShaderProgram which in turn deletes the QGLShaders

            newProg = 0;

        }

        else {

            if (vertexShader)

                delete vertexShader;

            if (fragShader)

                delete fragShader;

        }

    }

    return newProg;

}

void QGLEngineSharedShaders::cleanupCustomStage(QGLCustomShaderStage* stage)

{

    // Remove any shader programs which has this as the custom shader src:

    for (int i = 0; i < cachedPrograms.size(); ++i) {

        QGLEngineShaderProg *cachedProg = cachedPrograms[i];

        if (cachedProg->customStageSource == stage->source()) {

            delete cachedProg;

            cachedPrograms.removeAt(i);

            i--;

        }

    }

}

QGLEngineShaderManager::QGLEngineShaderManager(QGLContext* context)

    : ctx(context),

      shaderProgNeedsChanging(true),

      srcPixelType(Qt::NoBrush),

      opacityMode(NoOpacity),

      maskType(NoMask),

      compositionMode(QPainter::CompositionMode_SourceOver),

      customSrcStage(0),

      currentShaderProg(0)

{

    sharedShaders = QGLEngineSharedShaders::shadersForContext(context);

    connect(sharedShaders, SIGNAL(shaderProgNeedsChanging()), this, SLOT(shaderProgNeedsChangingSlot()));

}

QGLEngineShaderManager::~QGLEngineShaderManager()

{

    //###

    removeCustomStage();

}

GLuint QGLEngineShaderManager::getUniformLocation(Uniform id)

{

    if (!currentShaderProg)

        return 0;

    QVector<uint> &uniformLocations = currentShaderProg->uniformLocations;

    if (uniformLocations.isEmpty())

        uniformLocations.fill(GLuint(-1), NumUniforms);

    static const char *uniformNames[] = {

        "imageTexture",

        "patternColor",

        "globalOpacity",

        "depth",

        "maskTexture",

        "fragmentColor",

        "linearData",

        "angle",

        "halfViewportSize",

        "fmp",

        "fmp2_m_radius2",

        "inverse_2_fmp2_m_radius2",

        "invertedTextureSize",

        "brushTransform",

    };

    if (uniformLocations.at(id) == GLuint(-1))

        uniformLocations[id] = currentShaderProg->program->uniformLocation(uniformNames[id]);

    return uniformLocations.at(id);

}

void QGLEngineShaderManager::optimiseForBrushTransform(QTransform::TransformationType transformType)

{

    Q_UNUSED(transformType); // Currently ignored

}

void QGLEngineShaderManager::setDirty()

{

    shaderProgNeedsChanging = true;

}

void QGLEngineShaderManager::setSrcPixelType(Qt::BrushStyle style)

{

    Q_ASSERT(style != Qt::NoBrush);

    if (srcPixelType == PixelSrcType(style))

        return;

    srcPixelType = style;

    shaderProgNeedsChanging = true; //###

}

void QGLEngineShaderManager::setSrcPixelType(PixelSrcType type)

{

    if (srcPixelType == type)

        return;

    srcPixelType = type;

    shaderProgNeedsChanging = true; //###

}

void QGLEngineShaderManager::setOpacityMode(OpacityMode mode)

{

    if (opacityMode == mode)

        return;

    opacityMode = mode;

    shaderProgNeedsChanging = true; //###

}

void QGLEngineShaderManager::setMaskType(MaskType type)

{

    if (maskType == type)

        return;

    maskType = type;

    shaderProgNeedsChanging = true; //###

}

void QGLEngineShaderManager::setCompositionMode(QPainter::CompositionMode mode)