qgsproperty.h

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/***************************************************************************
     qgsproperty.h
     -------------
    Date                 : January 2017
    Copyright            : (C) 2017 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 QGSPROPERTY_H
#define QGSPROPERTY_H

#include "qgis_core.h"
#include "qgis.h"
#include "qgsproperty_p.h"
#include "qgsexpression.h"
#include "qgsexpressioncontext.h"
#include "qgscolorramp.h"

#include <QVariant>
#include <QHash>
#include <QString>
#include <QStringList>
#include <QDomElement>
#include <QDomDocument>
#include <QColor>

class QgsPropertyTransformer;

class CORE_EXPORT QgsPropertyDefinition
{
  public:

    enum StandardPropertyTemplate
    {
      Boolean = 0, 
      Integer, 
      IntegerPositive, 
      IntegerPositiveGreaterZero, 
      Double, 
      DoublePositive, 
      Double0To1, 
      Rotation, 
      String, 
      Opacity, 
      RenderUnits, 
      ColorWithAlpha, 
      ColorNoAlpha, 
      PenJoinStyle, 
      BlendMode, 
      Point, 
      Size, 
      Size2D, 
      LineStyle, 
      StrokeWidth, 
      FillStyle, 
      CapStyle, 
      HorizontalAnchor, 
      VerticalAnchor, 
      SvgPath, 
      Offset, 
      Custom = 3000, 
    };

    enum DataType
    {

      DataTypeString = 0,

      DataTypeNumeric,

      DataTypeBoolean,
    };

    QgsPropertyDefinition() = default;

    QgsPropertyDefinition( const QString &name, const QString &description, StandardPropertyTemplate type, const QString &origin = QString(), const QString &comment = QString() );

    QgsPropertyDefinition( const QString &name, DataType dataType, const QString &description, const QString &helpText, const QString &origin = QString(), const QString &comment = QString() );

    QString name() const { return mName; }

    void setName( const QString &name ) { mName = name; }

    QString origin() const { return mOrigin; }

    void setOrigin( const QString &origin ) { mOrigin = origin; }

    QString description() const { return mDescription; }

    QString comment() const { return mComment; }

    void setComment( const QString &comment ) { mComment = comment; }

    QString helpText() const { return mHelpText; }

    void setDataType( DataType type ) { mTypes = type; }

    DataType dataType() const { return mTypes; }

    StandardPropertyTemplate standardTemplate() const { return mStandardType; }

    bool supportsAssistant() const;

  private:

    QString mName;
    QString mDescription;
    DataType mTypes = DataTypeString;
    QString mHelpText;
    StandardPropertyTemplate mStandardType = Custom;
    QString mOrigin;
    QString mComment;

    static QString trString();
};


class CORE_EXPORT QgsProperty
{
  public:

    enum Type
    {
      InvalidProperty, 
      StaticProperty, 
      FieldBasedProperty, 
      ExpressionBasedProperty, 
    };

    QgsProperty();

    virtual ~QgsProperty() = default;

    static QgsProperty fromExpression( const QString &expression, bool isActive = true );

    static QgsProperty fromField( const QString &fieldName, bool isActive = true );

    static QgsProperty fromValue( const QVariant &value, bool isActive = true );

    QgsProperty( const QgsProperty &other );

    QgsProperty &operator=( const QgsProperty &other );

    operator bool() const;

    bool operator==( const QgsProperty &other ) const;
    bool operator!=( const QgsProperty &other ) const;

    Type propertyType() const;

    bool isActive() const;

    void setActive( bool active );

    void setStaticValue( const QVariant &value );

    QVariant staticValue() const;

    void setField( const QString &field );

    QString field() const;

    void setExpressionString( const QString &expression );

    QString expressionString() const;

    QString asExpression() const;

    bool prepare( const QgsExpressionContext &context = QgsExpressionContext() ) const;

    QSet< QString > referencedFields( const QgsExpressionContext &context = QgsExpressionContext() ) const;

    QVariant value( const QgsExpressionContext &context, const QVariant &defaultValue = QVariant(), bool *ok SIP_OUT = nullptr ) const;

    QString valueAsString( const QgsExpressionContext &context, const QString &defaultString = QString(), bool *ok SIP_OUT = nullptr ) const;

    QColor valueAsColor( const QgsExpressionContext &context, const QColor &defaultColor = QColor(), bool *ok SIP_OUT = nullptr ) const;

    double valueAsDouble( const QgsExpressionContext &context, double defaultValue = 0.0, bool *ok SIP_OUT = nullptr ) const;

    int valueAsInt( const QgsExpressionContext &context, int defaultValue = 0, bool *ok SIP_OUT = nullptr ) const;

    bool valueAsBool( const QgsExpressionContext &context, bool defaultValue = false, bool *ok SIP_OUT = nullptr ) const;

    QVariant toVariant() const;

    bool loadVariant( const QVariant &property );

    void setTransformer( QgsPropertyTransformer *transformer SIP_TRANSFER );

    const QgsPropertyTransformer *transformer() const;

    bool convertToTransformer();

    operator QVariant() const
    {
      return QVariant::fromValue( *this );
    }

  private:

    mutable QExplicitlySharedDataPointer<QgsPropertyPrivate> d;

    QVariant propertyValue( const QgsExpressionContext &context, const QVariant &defaultValue = QVariant(), bool *ok = nullptr ) const;

};

Q_DECLARE_METATYPE( QgsProperty )

#endif // QGSPROPERTY_H