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#include "qshaderprogrambuilder.h"
#include "qshaderprogrambuilder_p.h"
#include "qshaderprogram.h"
#include <Qt3DCore/qpropertyupdatedchange.h>
#include <Qt3DRender/private/qurlhelper_p.h>
#include <QDebug>
#include <QFile>
#include <QFileInfo>
#include <QUrl>

/*!
    \class Qt3DRender::QShaderProgramBuilder
    \inmodule Qt3DRender
    \brief Generates a Shader Program content from loaded graphs.
    \inherits Qt3DCore::QNode
    \since 5.10

    A shader program builder consists of several different shader graphs
    used to generate shader code.
*/

/*!
    \qmltype ShaderProgramBuilder
    \instantiates Qt3DRender::QShaderProgramBuilder
    \inqmlmodule Qt3D.Render
    \brief Generates a Shader Program content from loaded graphs.
    \since 5.10

    A shader program builder consists of several different shader graphs
    used to generate shader code.
*/

QT_BEGIN_NAMESPACE

namespace Qt3DRender {

QShaderProgramBuilderPrivate::QShaderProgramBuilderPrivate()
    : QNodePrivate(),
      m_shaderProgram(nullptr)
{
}

QShaderProgramBuilder::QShaderProgramBuilder(QNode *parent)
    : QNode(*new QShaderProgramBuilderPrivate, parent)
{
}

QShaderProgramBuilder::~QShaderProgramBuilder()
{
}

/*! \internal */
QShaderProgramBuilder::QShaderProgramBuilder(QShaderProgramBuilderPrivate &dd, QNode *parent)
    : QNode(dd, parent)
{
}

void QShaderProgramBuilder::sceneChangeEvent(const Qt3DCore::QSceneChangePtr &change)
{
    Q_D(QShaderProgramBuilder);
    if (change->type() == Qt3DCore::PropertyUpdated) {
        const Qt3DCore::QPropertyUpdatedChangePtr e = qSharedPointerCast<Qt3DCore::QPropertyUpdatedChange>(change);
        if (e->propertyName() == QByteArrayLiteral("generatedShaderCode")) {
            const bool blocked = blockNotifications(true);
            const QPair<int, QByteArray> data = e->value().value<QPair<int, QByteArray>>();

            switch (data.first) {
            case QShaderProgram::Vertex: {
                d->m_vertexShaderCode = data.second;
                emit vertexShaderCodeChanged(d->m_vertexShaderCode);
                break;
            }
            case QShaderProgram::Fragment:{
                d->m_fragmentShaderCode = data.second;
                emit fragmentShaderCodeChanged(d->m_fragmentShaderCode);
                break;
            }
            case QShaderProgram::Geometry: {
                d->m_geometryShaderCode = data.second;
                emit geometryShaderCodeChanged(d->m_geometryShaderCode);
                break;
            }
            case QShaderProgram::Compute: {
                d->m_computeShaderCode = data.second;
                emit computeShaderCodeChanged(d->m_computeShaderCode);
                break;
            }
            case QShaderProgram::TessellationControl: {
                d->m_tessControlShaderCode = data.second;
                emit tessellationControlShaderCodeChanged(d->m_tessControlShaderCode);
                break;
            }
            case QShaderProgram::TessellationEvaluation: {
                d->m_tessEvalShaderCode = data.second;
                emit tessellationEvaluationShaderCodeChanged(d->m_tessEvalShaderCode);
                break;
            }
            }

            blockNotifications(blocked);
        }
    }
}

/*!
    \qmlproperty string ShaderProgramBuilder::shaderProgram

    Holds the shader program on which this builder generates code.
*/
/*!
    \property QShaderProgramBuilder::shaderProgram

    Holds the shader program on which this builder generates code.
*/
void QShaderProgramBuilder::setShaderProgram(QShaderProgram *program)
{
    Q_D(QShaderProgramBuilder);
    if (program != d->m_shaderProgram) {

        if (d->m_shaderProgram)
            d->unregisterDestructionHelper(d->m_shaderProgram);

        // We need to add it as a child of the current node if it has been declared inline
        // Or not previously added as a child of the current node so that
        // 1) The backend gets notified about it's creation
        // 2) When the current node is destroyed, it gets destroyed as well
        if (program && !program->parent())
            program->setParent(this);
        d->m_shaderProgram = program;

        // Ensures proper bookkeeping
        if (d->m_shaderProgram)
            d->registerDestructionHelper(d->m_shaderProgram, &QShaderProgramBuilder::setShaderProgram, d->m_shaderProgram);

        emit shaderProgramChanged(program);
    }
}

QShaderProgram *QShaderProgramBuilder::shaderProgram() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_shaderProgram;
}

/*!
    \qmlproperty stringlist ShaderProgramBuilder::enabledLayers

    Holds the list of layers this builder will activate on the shader graphs
    during code generation.
*/
/*!
    \property QShaderProgramBuilder::enabledLayers

    Holds the list of layers this builder will activate on the shader graphs
    during code generation.
*/
void QShaderProgramBuilder::setEnabledLayers(const QStringList &layers)
{
    Q_D(QShaderProgramBuilder);
    if (layers != d->m_enabledLayers) {
        d->m_enabledLayers = layers;
        emit enabledLayersChanged(layers);
    }
}

QStringList QShaderProgramBuilder::enabledLayers() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_enabledLayers;
}

/*!
    \qmlproperty string ShaderProgram::vertexShaderGraph

    Holds the URL to the vertex shader graph used by this shader program builder.
*/
/*!
    \property QShaderProgramBuilder::vertexShaderGraph

    Holds the URL to the vertex shader graph used by this shader program builder.
*/
void QShaderProgramBuilder::setVertexShaderGraph(const QUrl &vertexShaderGraph)
{
    Q_D(QShaderProgramBuilder);
    if (vertexShaderGraph != d->m_vertexShaderGraph) {
        d->m_vertexShaderGraph = vertexShaderGraph;
        emit vertexShaderGraphChanged(vertexShaderGraph);
    }
}

QUrl QShaderProgramBuilder::vertexShaderGraph() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_vertexShaderGraph;
}

/*!
    \qmlproperty string ShaderProgram::tessellationControlShaderGraph

    Holds the URL to the tesselation control shader graph used by this shader program builder.
*/
/*!
    \property QShaderProgramBuilder::tessellationControlShaderGraph

    Holds the URL to the tesselation control shader graph used by this shader program builder.
*/
void QShaderProgramBuilder::setTessellationControlShaderGraph(const QUrl &tessellationControlShaderGraph)
{
    Q_D(QShaderProgramBuilder);
    if (tessellationControlShaderGraph != d->m_tessControlShaderGraph) {
        d->m_tessControlShaderGraph = tessellationControlShaderGraph;
        emit tessellationControlShaderGraphChanged(tessellationControlShaderGraph);
    }
}

QUrl QShaderProgramBuilder::tessellationControlShaderGraph() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_tessControlShaderGraph;
}

/*!
    \qmlproperty string ShaderProgram::tessellationEvaluationShaderGraph

    Holds the URL to the tesselation evaluation shader graph used by this shader program builder.
*/
/*!
    \property QShaderProgramBuilder::tessellationEvaluationShaderGraph

    Holds the URL to the tesselation evaluation shader graph used by this shader program builder.
*/
void QShaderProgramBuilder::setTessellationEvaluationShaderGraph(const QUrl &tessellationEvaluationShaderGraph)
{
    Q_D(QShaderProgramBuilder);
    if (tessellationEvaluationShaderGraph != d->m_tessEvalShaderGraph) {
        d->m_tessEvalShaderGraph = tessellationEvaluationShaderGraph;
        emit tessellationEvaluationShaderGraphChanged(tessellationEvaluationShaderGraph);
    }
}

QUrl QShaderProgramBuilder::tessellationEvaluationShaderGraph() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_tessEvalShaderGraph;
}

/*!
    \qmlproperty string ShaderProgram::geometryShaderGraph

    Holds the URL to the geometry shader graph used by this shader program builder.
*/
/*!
    \property QShaderProgramBuilder::geometryShaderGraph

    Holds the URL to the geometry shader graph used by this shader program builder.
*/
void QShaderProgramBuilder::setGeometryShaderGraph(const QUrl &geometryShaderGraph)
{
    Q_D(QShaderProgramBuilder);
    if (geometryShaderGraph != d->m_geometryShaderGraph) {
        d->m_geometryShaderGraph = geometryShaderGraph;
        emit geometryShaderGraphChanged(geometryShaderGraph);
    }
}

QUrl QShaderProgramBuilder::geometryShaderGraph() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_geometryShaderGraph;
}

/*!
    \qmlproperty string ShaderProgram::fragmentShaderGraph

    Holds the URL to the fragment shader graph used by this shader program builder.
*/
/*!
    \property QShaderProgramBuilder::fragmentShaderGraph

    Holds the URL to the fragment shader graph used by this shader program builder.
*/
void QShaderProgramBuilder::setFragmentShaderGraph(const QUrl &fragmentShaderGraph)
{
    Q_D(QShaderProgramBuilder);
    if (fragmentShaderGraph != d->m_fragmentShaderGraph) {
        d->m_fragmentShaderGraph = fragmentShaderGraph;
        emit fragmentShaderGraphChanged(fragmentShaderGraph);
    }
}

QUrl QShaderProgramBuilder::fragmentShaderGraph() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_fragmentShaderGraph;
}

/*!
    \qmlproperty string ShaderProgram::computeShaderGraph

    Holds the URL to the compute shader graph used by this shader program builder.
*/
/*!
    \property QShaderProgramBuilder::computeShaderGraph

    Holds the URL to the compute shader graph used by this shader program builder.
*/
void QShaderProgramBuilder::setComputeShaderGraph(const QUrl &computeShaderGraph)
{
    Q_D(QShaderProgramBuilder);
    if (computeShaderGraph != d->m_computeShaderGraph) {
        d->m_computeShaderGraph = computeShaderGraph;
        emit computeShaderGraphChanged(computeShaderGraph);
    }
}

QUrl QShaderProgramBuilder::computeShaderGraph() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_computeShaderGraph;
}

/*!
    \qmlproperty string ShaderProgramBuilder:vertexShaderCode

    Holds the generated vertex shader code
    \since 2.13
*/
/*!
    \property QShaderProgram:Builder:vertexShaderCode

    Holds the generate vertex shader code.
    \since 5.13
*/
QByteArray QShaderProgramBuilder::vertexShaderCode() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_vertexShaderCode;
}

/*!
    \qmlproperty string ShaderProgramBuilder:tessellationControlShaderCode

    Holds the generated tessellation control shader code
    \since 2.13
*/
/*!
    \property QShaderProgram:Builder:tessellationControlShaderCode

    Holds the generate tessellation control shader code.
    \since 5.13
*/
QByteArray QShaderProgramBuilder::tessellationControlShaderCode() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_tessControlShaderCode;
}

/*!
    \qmlproperty string ShaderProgramBuilder:tessellationEvaluationShaderCode

    Holds the generated tessellation evaluation shader code
    \since 2.13
*/
/*!
    \property QShaderProgram:Builder:tessellationEvaluationShaderCode

    Holds the generate tessellation evaluation shader code.
    \since 5.13
*/
QByteArray QShaderProgramBuilder::tessellationEvaluationShaderCode() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_tessEvalShaderCode;
}

/*!
    \qmlproperty string ShaderProgramBuilder:geometryShaderCode

    Holds the generated geometry shader code
    \since 2.13
*/
/*!
    \property QShaderProgram:Builder:geometryShaderCode

    Holds the generate geometry shader code.
    \since 5.13
*/
QByteArray QShaderProgramBuilder::geometryShaderCode() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_geometryShaderCode;
}

/*!
    \qmlproperty string ShaderProgramBuilder::fragmentShaderCode

    Holds the generated fragment shader code
    \since 2.13
*/
/*!
    \property QShaderProgram:Builder:fragmentShaderCode

    Holds the generate fragment shader code.
    \since 5.13
*/
QByteArray QShaderProgramBuilder::fragmentShaderCode() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_fragmentShaderCode;
}

/*!
    \qmlproperty string ShaderProgramBuilder::computeShaderCode

    Holds the generated compute shader code
    \since 2.13
*/
/*!
    \property QShaderProgram:Builder:computeShaderCode

    Holds the generate compute shader code.
    \since 5.13
*/
QByteArray QShaderProgramBuilder::computeShaderCode() const
{
    Q_D(const QShaderProgramBuilder);
    return d->m_computeShaderCode;
}

Qt3DCore::QNodeCreatedChangeBasePtr QShaderProgramBuilder::createNodeCreationChange() const
{
    auto creationChange = Qt3DCore::QNodeCreatedChangePtr<QShaderProgramBuilderData>::create(this);
    auto &data = creationChange->data;
    Q_D(const QShaderProgramBuilder);
    data.shaderProgramId = d->m_shaderProgram ? d->m_shaderProgram->id() : Qt3DCore::QNodeId();
    data.enabledLayers = d->m_enabledLayers;
    data.vertexShaderGraph = d->m_vertexShaderGraph;
    data.tessellationControlShaderGraph = d->m_tessControlShaderGraph;
    data.tessellationEvaluationShaderGraph = d->m_tessEvalShaderGraph;
    data.geometryShaderGraph = d->m_geometryShaderGraph;
    data.fragmentShaderGraph = d->m_fragmentShaderGraph;
    data.computeShaderGraph = d->m_computeShaderGraph;
    return creationChange;
}

} // of namespace Qt3DRender

QT_END_NAMESPACE