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#ifndef QSSG_RENDER_CUSTOM_MATERIAL_H
#define QSSG_RENDER_CUSTOM_MATERIAL_H

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

#include <QtQuick3DRuntimeRender/private/qssgrenderimage_p.h>
#include <QtQuick3DRuntimeRender/private/qssgrenderlightmaps_p.h>
#include <QtQuick3DRuntimeRender/private/qssgrenderdynamicobjectsystemcommands_p.h>

#include <QtCore/qurl.h>
#include <QtCore/qvector.h>

QT_BEGIN_NAMESPACE

struct Q_QUICK3DRUNTIMERENDER_EXPORT QSSGRenderCustomMaterial : public QSSGRenderGraphObject
{
    QSSGRenderCustomMaterial() : QSSGRenderGraphObject(Type::CustomMaterial) {}

    struct TextureProperty
    {
        QSSGRenderImage *texImage = nullptr;
        QByteArray name;
        QSSGRenderShaderDataType shaderDataType;
        QSSGRenderTextureMagnifyingOp magFilterType = QSSGRenderTextureMagnifyingOp::Linear;
        QSSGRenderTextureMinifyingOp minFilterType = QSSGRenderTextureMinifyingOp::Linear;
        QSSGRenderTextureCoordOp clampType = QSSGRenderTextureCoordOp::ClampToEdge;
    };

    QVector<TextureProperty> textureProperties;

    struct Property
    {
        Property() = default;
        Property(const QByteArray &name, const QVariant &value, QSSGRenderShaderDataType shaderDataType, int pid = -1)
            : name(name), value(value), shaderDataType(shaderDataType), pid(pid)
        { }
        QByteArray name;
        mutable QVariant value;
        QSSGRenderShaderDataType shaderDataType;
        int pid;
    };

    QVector<Property> properties;

    struct ShaderInfo
    {
        QByteArray version;
        QByteArray type; // I.e., GLSL
        QByteArray shaderPrefix;
    };

    ShaderInfo shaderInfo;

    struct Shader
    {
        enum class Stage : quint8
        {
            Shared,
            Vertex,
            Fragment
        };

        QString code;
        Stage stage;
    };

    QVector<Shader> shaders;

    struct Pass
    {
        struct BufferInput
        {
            QString bufferName;
            QString shaderParam;
            // dynamic::QSSGApplyBufferValue(bufferName, shaderParam)
        };

        struct BufferBlit
        {
            QString source;
            QString dest;
            // dynamic::QSSGApplyBlitFramebuffer(source, dest)
        };

        struct Blending
        {
            QSSGRenderSrcBlendFunc source = QSSGRenderSrcBlendFunc::One;
            QSSGRenderDstBlendFunc dest = QSSGRenderDstBlendFunc::One;
            // hasBlending = true; when used
            // dynamic::QSSGApplyBlending(source, dest)
        };

        struct RenderState
        {
            QSSGRenderState renderState = QSSGRenderState::Unknown;
            bool enabled;
            // dynamic::QSSGApplyRenderState(renderState, enabled)
        };

        QString shaderName;
        QString input;
        QString output;
        QSSGRenderTextureFormat::Format outputFormat;
        bool needsClear;

        Pass()
            : input(QLatin1String("[source]"))
            , output(QLatin1String("[dest]"))
            , outputFormat(QSSGRenderTextureFormat::RGBA8)
            , needsClear(false)
        {}
    };

    QVector<Pass> passes;
    QVector<dynamic::QSSGCommand *> commands;

    // IMPORTANT: These flags matches the key produced by a MDL export file
    enum class MaterialShaderKeyValues
    {
        diffuse = 1 << 0,
        specular = 1 << 1,
        cutout = 1 << 2,
        refraction = 1 << 3,
        transparent = 1 << 4,
        displace = 1 << 5,
        transmissive = 1 << 6,
    };
    Q_DECLARE_FLAGS(MaterialShaderKeyFlags, MaterialShaderKeyValues)

    using Flag = QSSGRenderNode::Flag;
    Q_DECLARE_FLAGS(Flags, Flag)

    const char *className = nullptr;

    // lightmap section
    QSSGRenderLightmaps m_lightmaps;
    // material section
    bool m_hasTransparency = false;
    bool m_hasRefraction = false;
    QSSGRenderImage *m_iblProbe = nullptr;
    QSSGRenderImage *m_emissiveMap = nullptr;
    QSSGRenderImage *m_displacementMap = nullptr;
    float m_displaceAmount = 0.0f; ///< depends on the object size
    QSSGCullFaceMode cullingMode = QSSGCullFaceMode::Back;

    QSSGRenderGraphObject *m_nextSibling = nullptr;

    MaterialShaderKeyFlags m_shaderKeyValues; ///< input from MDL files

    Flags flags;
    bool m_alwaysDirty = false;

    bool isDielectric() const { return m_shaderKeyValues & MaterialShaderKeyValues::diffuse; }
    bool isSpecularEnabled() const { return m_shaderKeyValues & MaterialShaderKeyValues::specular; }
    bool isCutOutEnabled() const { return m_shaderKeyValues & MaterialShaderKeyValues::cutout; }
    bool isTransmissive() const { return m_shaderKeyValues & MaterialShaderKeyValues::transmissive; }
    bool hasLighting() const { return true; }

    // Dirty
    bool m_dirtyFlagWithInFrame;
    bool isDirty() const { return flags.testFlag(Flag::Dirty) || m_dirtyFlagWithInFrame || m_alwaysDirty; }
    void updateDirtyForFrame()
    {
        m_dirtyFlagWithInFrame = flags.testFlag(Flag::Dirty);
        flags.setFlag(Flag::Dirty, false);
    }
};

Q_DECLARE_OPERATORS_FOR_FLAGS(QSSGRenderCustomMaterial::MaterialShaderKeyFlags)

QT_END_NAMESPACE

#endif
