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#ifndef QQUICKSHADEREFFECTNODE_P_H
#define QQUICKSHADEREFFECTNODE_P_H

#include <QtQuick/qsgnode.h>
#include <QtQuick/qsgmaterial.h>
#include <QtQuick/qsgtextureprovider.h>
#include <QtQuick/qquickitem.h>

#include <QtCore/qsharedpointer.h>
#include <QtCore/qpointer.h>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

struct QQuickShaderEffectMaterialKey {
    QByteArray vertexCode;
    QByteArray fragmentCode;
    const char *className;

    bool operator == (const QQuickShaderEffectMaterialKey &other) const;
};

uint qHash(const QQuickShaderEffectMaterialKey &key);

// TODO: Implement support for multisampling.
struct QQuickShaderEffectProgram : public QQuickShaderEffectMaterialKey
{
    QQuickShaderEffectProgram() : respectsOpacity(false), respectsMatrix(false) {}

    QVector<QByteArray> attributeNames;
    QSet<QByteArray> uniformNames;

    uint respectsOpacity : 1;
    uint respectsMatrix : 1;
};


class QQuickCustomMaterialShader;
class QQuickShaderEffectNode;
class QQuickShaderEffectMaterial : public QSGMaterial
{
public:
    enum CullMode
    {
        NoCulling,
        BackFaceCulling,
        FrontFaceCulling
    };

    explicit QQuickShaderEffectMaterial(QQuickShaderEffectNode *node = 0);
    virtual QSGMaterialType *type() const;
    virtual QSGMaterialShader *createShader() const;
    virtual int compare(const QSGMaterial *other) const;

    void setCullMode(CullMode face);
    CullMode cullMode() const;

    void setProgramSource(const QQuickShaderEffectProgram &);
    void setUniforms(const QVector<QPair<QByteArray, QVariant> > &uniformValues);
    void setTextureProviders(const QVector<QPair<QByteArray, QSGTextureProvider *> > &textures);
    const QVector<QPair<QByteArray, QSGTextureProvider *> > &textureProviders() const;
    void updateTextures() const;

protected:
    friend class QQuickCustomMaterialShader;

    // The type pointer needs to be unique. It is not safe to let the type object be part of the
    // QQuickShaderEffectMaterial, since it can be deleted and a new one constructed on top of the old
    // one. The new QQuickShaderEffectMaterial would then get the same type pointer as the old one, and
    // CustomMaterialShaders based on the old one would incorrectly be used together with the new
    // one. To guarantee that the type pointer is unique, the type object must live as long as
    // there are any CustomMaterialShaders of that type.
    QSharedPointer<QSGMaterialType> m_type;

    QQuickShaderEffectProgram m_source;
    QVector<QPair<QByteArray, QVariant> > m_uniformValues;
    QVector<QPair<QByteArray, QSGTextureProvider *> > m_textures;
    CullMode m_cullMode;
    QQuickShaderEffectNode *m_node;
    bool m_emittedLogChanged;

    static QHash<QQuickShaderEffectMaterialKey, QSharedPointer<QSGMaterialType> > materialMap;
};


class QSGShaderEffectMesh;

class QQuickShaderEffectNode : public QObject, public QSGGeometryNode
{
    Q_OBJECT
public:
    QQuickShaderEffectNode();
    virtual ~QQuickShaderEffectNode();

    virtual void preprocess();

    QQuickShaderEffectMaterial *shaderMaterial() { return &m_material; }

Q_SIGNALS:
    void logAndStatusChanged(const QString &, int status);

private Q_SLOTS:
    void markDirtyTexture();

private:
    QQuickShaderEffectMaterial m_material;
};

QT_END_NAMESPACE

QT_END_HEADER

#endif // QQUICKSHADEREFFECTNODE_P_H