/***************************************************************************
                         qgsmeshmemorydataprovider.h
                         ---------------------------
    begin                : April 2018
    copyright            : (C) 2018 by Peter Petrik
    email                : zilolv at gmail dot com
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/

#ifndef QGSMESHMEMORYDATAPROVIDER_H
#define QGSMESHMEMORYDATAPROVIDER_H

#define SIP_NO_FILE

///@cond PRIVATE

#include <QString>
#include <memory>

#include "qgis_core.h"
#include "qgis.h"
#include "qgsmeshdataprovider.h"
#include "qgsrectangle.h"

struct CORE_EXPORT QgsMeshMemoryDataset
{
  QgsMeshMemoryDataset();
  QgsMeshDataBlock datasetValues( bool isScalar, int valueIndex, int count ) const;
  QgsMeshDataBlock areFacesActive( int faceIndex, int count ) const;

  QVector<QgsMeshDatasetValue> values;
  QVector<int> active;
  double time = -1;
  bool valid = false;
  double minimum = std::numeric_limits<double>::quiet_NaN();
  double maximum = std::numeric_limits<double>::quiet_NaN();
};

struct CORE_EXPORT QgsMeshMemoryDatasetGroup
{
  QgsMeshMemoryDatasetGroup( const QString &nm, QgsMeshDatasetGroupMetadata::DataType dataType );
  QgsMeshMemoryDatasetGroup( const QString &nm );
  QgsMeshMemoryDatasetGroup();
  QgsMeshDatasetGroupMetadata groupMetadata() const;
  int datasetCount() const;
  void addDataset( std::shared_ptr<QgsMeshMemoryDataset> dataset );
  void clearDatasets();
  std::shared_ptr<const QgsMeshMemoryDataset> constDataset( int index ) const;

  QMap<QString, QString> metadata;
  QVector<std::shared_ptr<QgsMeshMemoryDataset>> datasets;
  QString name;
  bool isScalar = true;
  QgsMeshDatasetGroupMetadata::DataType type = QgsMeshDatasetGroupMetadata::DataOnVertices;
  double minimum = std::numeric_limits<double>::quiet_NaN();
  double maximum = std::numeric_limits<double>::quiet_NaN();
};

/**
 * \ingroup core
 * Provides data stored in-memory for QgsMeshLayer. Useful for plugins or tests.
 * \since QGIS 3.2
 */
class CORE_EXPORT QgsMeshMemoryDataProvider final: public QgsMeshDataProvider
{
    Q_OBJECT

  public:

    /**
     * Construct a mesh in-memory data provider from data string
     *
     * Data string contains simple definition of vertices and faces
     * Each entry is separated by "\n" sign and section deliminer "---"
     * vertex is x and y coordinate separated by comma
     * face is list of vertex indexes, numbered from 0
     * For example:
     *
     *  \code
     *    QString uri(
     *      "1.0, 2.0 \n" \
     *      "2.0, 2.0 \n" \
     *      "3.0, 2.0 \n" \
     *      "2.0, 3.0 \n" \
     *      "1.0, 3.0 \n" \
     *      "---"
     *      "0, 1, 3, 4 \n" \
     *      "1, 2, 3 \n"
     *    );
     * \endcode
     */
    QgsMeshMemoryDataProvider( const QString &uri, const QgsDataProvider::ProviderOptions &providerOptions );

    bool isValid() const override;
    QString name() const override;
    QString description() const override;
    QgsCoordinateReferenceSystem crs() const override;

    int vertexCount() const override;
    int faceCount() const override;
    void populateMesh( QgsMesh *mesh ) const override;
    QgsRectangle extent() const override;

    /**
     * Adds dataset to a mesh in-memory data provider from data string
     *
     * Data string contains simple definition of datasets
     * Each entry is separated by "\n" sign and section deliminer "---"
     * First section defines the dataset group: Vertex/Face Vector/Scalar Name
     * Second section defines the group metadata: key: value pairs
     * Third section defines the datasets (timesteps). First line is time,
     * other lines are values (one value on line). For vectors separated by comma
     *
     * For example:
     *
     *  \code
     *    QString uri(
     *      "Vertex Vector MyVertexVectorDataset\n" \
     *      "---"
     *      "description: My great dataset \n" \
     *      "reference_time: Midnight  \n" \
     *      "---"
     *      "0 \n"
     *      "3, 2 \n" \
     *      "1, -2 \n"
     *      "---"
     *      "1 \n"
     *      "2, 2 \n" \
     *      "2, -2 \n"
     *    );
     * \endcode
     */
    bool addDataset( const QString &uri ) override;
    QStringList extraDatasets() const override;
    int datasetGroupCount() const override;
    int datasetCount( int groupIndex ) const override;

    QgsMeshDatasetGroupMetadata datasetGroupMetadata( int groupIndex ) const override;
    QgsMeshDatasetMetadata datasetMetadata( QgsMeshDatasetIndex index ) const override;
    QgsMeshDatasetValue datasetValue( QgsMeshDatasetIndex index, int valueIndex ) const override;
    QgsMeshDataBlock datasetValues( QgsMeshDatasetIndex index, int valueIndex, int count ) const override;
    QgsMesh3dDataBlock dataset3dValues( QgsMeshDatasetIndex index, int faceIndex, int count ) const override;

    bool isFaceActive( QgsMeshDatasetIndex index, int faceIndex ) const override;
    QgsMeshDataBlock areFacesActive( QgsMeshDatasetIndex index, int faceIndex, int count ) const override;
    bool persistDatasetGroup( const QString &path,
                              const QgsMeshDatasetGroupMetadata &meta,
                              const QVector<QgsMeshDataBlock> &datasetValues,
                              const QVector<QgsMeshDataBlock> &datasetActive,
                              const QVector<double> &times
                            ) override;

    //! Returns the memory provider key
    static QString providerKey();
    //! Returns the memory provider description
    static QString providerDescription();
    //! Provider factory
    static QgsMeshMemoryDataProvider *createProvider( const QString &uri, const QgsDataProvider::ProviderOptions &providerOptions );

  private:
    void calculateMinMaxForDatasetGroup( QgsMeshMemoryDatasetGroup &grp ) const;
    void calculateMinMaxForDataset( std::shared_ptr<QgsMeshMemoryDataset> &dataset ) const;
    QgsRectangle calculateExtent( ) const;

    bool splitMeshSections( const QString &uri );
    bool addMeshVertices( const QString &def );
    bool addMeshFaces( const QString &def );

    bool splitDatasetSections( const QString &uri, QgsMeshMemoryDatasetGroup &datasetGroup );
    bool setDatasetGroupType( const QString &uri, QgsMeshMemoryDatasetGroup &datasetGroup );
    bool addDatasetGroupMetadata( const QString &def, QgsMeshMemoryDatasetGroup &datasetGroup );
    bool addDatasetValues( const QString &def, std::shared_ptr<QgsMeshMemoryDataset> &dataset, bool isScalar );
    bool checkDatasetValidity( std::shared_ptr<QgsMeshMemoryDataset> &dataset, bool isOnVertices );

    QVector<QgsMeshVertex> mVertices;
    QVector<QgsMeshFace> mFaces;
    QVector<QgsMeshMemoryDatasetGroup> mDatasetGroups;

    bool mIsValid = false;
    QStringList mExtraDatasetUris;
};

///@endcond

#endif // QGSMESHMEMORYDATAPROVIDER_H
