qgsvectorlayerutils.h

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/***************************************************************************
  qgsvectorlayerutils.h
  ---------------------
  Date                 : October 2016
  Copyright            : (C) 2016 by Nyall Dawson
  Email                : nyall dot dawson 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 QGSVECTORLAYERUTILS_H
#define QGSVECTORLAYERUTILS_H

#include "qgis_core.h"
#include "qgsgeometry.h"
#include "qgsvectorlayerfeatureiterator.h"

class CORE_EXPORT QgsVectorLayerUtils
{
  public:

    class CORE_EXPORT QgsDuplicateFeatureContext
    {
      public:

        QgsDuplicateFeatureContext() = default;

        QList<QgsVectorLayer *> layers() const;

        QgsFeatureIds duplicatedFeatures( QgsVectorLayer *layer ) const;


      private:
        QMap<QgsVectorLayer *, QgsFeatureIds> mDuplicatedFeatures;
        friend class QgsVectorLayerUtils;

        void setDuplicatedFeatures( QgsVectorLayer *layer, const QgsFeatureIds &ids );
    };

    class CORE_EXPORT QgsFeatureData
    {
      public:

        QgsFeatureData( const QgsGeometry &geometry = QgsGeometry(), const QgsAttributeMap &attributes = QgsAttributeMap() );

        QgsGeometry geometry() const;

        QgsAttributeMap attributes() const;

      private:
        QgsGeometry mGeometry;
        QgsAttributeMap mAttributes;
    };

    // SIP does not like "using", use legacy typedef
    typedef QList<QgsVectorLayerUtils::QgsFeatureData> QgsFeaturesDataList;

    static QgsFeatureIterator getValuesIterator( const QgsVectorLayer *layer, const QString &fieldOrExpression, bool &ok, bool selectedOnly );

    static QList< QVariant > getValues( const QgsVectorLayer *layer, const QString &fieldOrExpression, bool &ok, bool selectedOnly = false, QgsFeedback *feedback = nullptr );

    static QList< double > getDoubleValues( const QgsVectorLayer *layer, const QString &fieldOrExpression, bool &ok, bool selectedOnly = false, int *nullCount = nullptr, QgsFeedback *feedback = nullptr );

    static bool valueExists( const QgsVectorLayer *layer, int fieldIndex, const QVariant &value, const QgsFeatureIds &ignoreIds = QgsFeatureIds() );

    static QVariant createUniqueValue( const QgsVectorLayer *layer, int fieldIndex, const QVariant &seed = QVariant() );

    static QVariant createUniqueValueFromCache( const QgsVectorLayer *layer, int fieldIndex, const QSet<QVariant> &existingValues, const QVariant &seed = QVariant() );

    static bool validateAttribute( const QgsVectorLayer *layer, const QgsFeature &feature, int attributeIndex, QStringList &errors SIP_OUT,
                                   QgsFieldConstraints::ConstraintStrength strength = QgsFieldConstraints::ConstraintStrengthNotSet,
                                   QgsFieldConstraints::ConstraintOrigin origin = QgsFieldConstraints::ConstraintOriginNotSet );

    static QgsFeature createFeature( const QgsVectorLayer *layer,
                                     const QgsGeometry &geometry = QgsGeometry(),
                                     const QgsAttributeMap &attributes = QgsAttributeMap(),
                                     QgsExpressionContext *context = nullptr );

    static QgsFeatureList createFeatures( const QgsVectorLayer *layer,
                                          const QgsFeaturesDataList &featuresData,
                                          QgsExpressionContext *context = nullptr );

    static QgsFeature duplicateFeature( QgsVectorLayer *layer, const QgsFeature &feature, QgsProject *project, int depth, QgsDuplicateFeatureContext &duplicateFeatureContext SIP_OUT );

    static std::unique_ptr<QgsVectorLayerFeatureSource> getFeatureSource( QPointer<QgsVectorLayer> layer, QgsFeedback *feedback = nullptr ) SIP_SKIP;

    static void matchAttributesToFields( QgsFeature &feature, const QgsFields &fields );

    static QgsFeatureList makeFeatureCompatible( const QgsFeature &feature, const QgsVectorLayer *layer );

    static QgsFeatureList makeFeaturesCompatible( const QgsFeatureList &features, const QgsVectorLayer *layer );

};


#endif // QGSVECTORLAYERUTILS_H