qgsalgorithmaddtablefield.cpp

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/***************************************************************************
                         qgsalgorithmaddtablefield.cpp
                         -----------------------------------
    begin                : November 2019
    copyright            : (C) 2019 by Alexander Bruy
    email                : alexander dot bruy 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.                                   *
 *                                                                         *
 ***************************************************************************/
 
#include "qgsalgorithmaddtablefield.h"
 
#include "qgsvariantutils.h"
 
#include <QString>
 
using namespace Qt::StringLiterals;

 
QString QgsAddTableFieldAlgorithm::name() const
{
  return u"addfieldtoattributestable"_s;
}
 
QString QgsAddTableFieldAlgorithm::displayName() const
{
  return QObject::tr( "Add field to attributes table" );
}
 
QString QgsAddTableFieldAlgorithm::shortHelpString() const
{
  return QObject::tr(
    "This algorithm adds a new attribute to a vector layer.\n\n"
    "The name and characteristics of the attribute are defined as parameters. The new attribute "
    "is not added to the input layer but a new layer is generated instead."
  );
}
 
QString QgsAddTableFieldAlgorithm::shortDescription() const
{
  return QObject::tr( "Adds a new attribute to a vector layer." );
}
 
QStringList QgsAddTableFieldAlgorithm::tags() const
{
  return QObject::tr( "add,create,new,attribute,fields" ).split( ',' );
}
 
QString QgsAddTableFieldAlgorithm::group() const
{
  return QObject::tr( "Vector table" );
}
 
QString QgsAddTableFieldAlgorithm::groupId() const
{
  return u"vectortable"_s;
}
 
QString QgsAddTableFieldAlgorithm::outputName() const
{
  return QObject::tr( "Added" );
}
 
QList<int> QgsAddTableFieldAlgorithm::inputLayerTypes() const
{
  return QList<int>() << static_cast<int>( Qgis::ProcessingSourceType::Vector );
}
 
Qgis::ProcessingFeatureSourceFlags QgsAddTableFieldAlgorithm::sourceFlags() const
{
  return Qgis::ProcessingFeatureSourceFlag::SkipGeometryValidityChecks;
}
 
QgsAddTableFieldAlgorithm *QgsAddTableFieldAlgorithm::createInstance() const
{
  return new QgsAddTableFieldAlgorithm();
}
 
void QgsAddTableFieldAlgorithm::initParameters( const QVariantMap & )
{
  addParameter( new QgsProcessingParameterString( u"FIELD_NAME"_s, QObject::tr( "Field name" ) ) );
 
  QStringList typeStrings;
  QVariantList icons;
  typeStrings.reserve( 11 );
  icons.reserve( 11 );
  for ( const auto &type : std::vector<std::pair<QMetaType::Type, QMetaType::Type>> {
          { QMetaType::Type::Int, QMetaType::Type::UnknownType },
          { QMetaType::Type::Double, QMetaType::Type::UnknownType },
          { QMetaType::Type::QString, QMetaType::Type::UnknownType },
          { QMetaType::Type::Bool, QMetaType::Type::UnknownType },
          { QMetaType::Type::QDate, QMetaType::Type::UnknownType },
          { QMetaType::Type::QTime, QMetaType::Type::UnknownType },
          { QMetaType::Type::QDateTime, QMetaType::Type::UnknownType },
          { QMetaType::Type::QByteArray, QMetaType::Type::UnknownType },
          { QMetaType::Type::QStringList, QMetaType::Type::UnknownType },
          { QMetaType::Type::QVariantList, QMetaType::Type::Int },
          { QMetaType::Type::QVariantList, QMetaType::Type::Double }
        } )
  {
    typeStrings << QgsVariantUtils::typeToDisplayString( type.first, type.second );
    icons << QgsFields::iconForFieldType( type.first, type.second );
  }
 
  auto fieldTypes = std::make_unique<QgsProcessingParameterEnum>( u"FIELD_TYPE"_s, QObject::tr( "Field type" ), typeStrings, false, 0 );
  fieldTypes->setMetadata( { QVariantMap( { { u"widget_wrapper"_s, QVariantMap( { { u"icons"_s, icons } } ) } } ) } );
  addParameter( fieldTypes.release() );
  addParameter( new QgsProcessingParameterNumber( u"FIELD_LENGTH"_s, QObject::tr( "Field length" ), Qgis::ProcessingNumberParameterType::Integer, 10, false, 1, 255 ) );
  addParameter( new QgsProcessingParameterNumber( u"FIELD_PRECISION"_s, QObject::tr( "Field precision" ), Qgis::ProcessingNumberParameterType::Integer, 0, false, 0, 10 ) );
 
  addParameter( new QgsProcessingParameterString( u"FIELD_ALIAS"_s, QObject::tr( "Field alias" ), QVariant(), false, true ) );
  addParameter( new QgsProcessingParameterString( u"FIELD_COMMENT"_s, QObject::tr( "Field comment" ), QVariant(), false, true ) );
}
 
QgsFields QgsAddTableFieldAlgorithm::outputFields( const QgsFields &inputFields ) const
{
  QgsFields outFields = inputFields;
  outFields.append( QgsField( mField ) );
  return outFields;
}
 
bool QgsAddTableFieldAlgorithm::prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback * )
{
  std::unique_ptr<QgsProcessingFeatureSource> source( parameterAsSource( parameters, u"INPUT"_s, context ) );
  const QString name = parameterAsString( parameters, u"FIELD_NAME"_s, context );
  const int type = parameterAsInt( parameters, u"FIELD_TYPE"_s, context );
  const int length = parameterAsInt( parameters, u"FIELD_LENGTH"_s, context );
  const int precision = parameterAsInt( parameters, u"FIELD_PRECISION"_s, context );
  const QString alias = parameterAsString( parameters, u"FIELD_ALIAS"_s, context );
  const QString comment = parameterAsString( parameters, u"FIELD_COMMENT"_s, context );
 
  if ( source->fields().lookupField( name ) >= 0 )
  {
    throw QgsProcessingException( QObject::tr( "A field with the same name (%1) already exists" ).arg( name ) );
  }
 
  mField.setName( name );
  mField.setLength( length );
  mField.setPrecision( precision );
  mField.setAlias( alias );
  mField.setComment( comment );
 
  switch ( type )
  {
    case 0: // Integer
      mField.setType( QMetaType::Type::Int );
      break;
    case 1: // Float
      mField.setType( QMetaType::Type::Double );
      break;
    case 2: // String
      mField.setType( QMetaType::Type::QString );
      break;
    case 3: // Boolean
      mField.setType( QMetaType::Type::Bool );
      break;
    case 4: // Date
      mField.setType( QMetaType::Type::QDate );
      break;
    case 5: // Time
      mField.setType( QMetaType::Type::QTime );
      break;
    case 6: // DateTime
      mField.setType( QMetaType::Type::QDateTime );
      break;
    case 7: // Binary
      mField.setType( QMetaType::Type::QByteArray );
      break;
    case 8: // StringList
      mField.setType( QMetaType::Type::QStringList );
      mField.setSubType( QMetaType::Type::QString );
      break;
    case 9: // IntegerList
      mField.setType( QMetaType::Type::QVariantList );
      mField.setSubType( QMetaType::Type::Int );
      break;
    case 10: // DoubleList
      mField.setType( QMetaType::Type::QVariantList );
      mField.setSubType( QMetaType::Type::Double );
      break;
  }
 
  return true;
}
 
QgsFeatureList QgsAddTableFieldAlgorithm::processFeature( const QgsFeature &feature, QgsProcessingContext &, QgsProcessingFeedback * )
{
  QgsFeature f = feature;
  QgsAttributes attributes = f.attributes();
  attributes.append( QVariant() );
  f.setAttributes( attributes );
  return QgsFeatureList() << f;
}
 
bool QgsAddTableFieldAlgorithm::supportInPlaceEdit( const QgsMapLayer *layer ) const
{
  Q_UNUSED( layer )
  return false;
}