qgsgmlschema.h

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/***************************************************************************
     qgsgmlschema.h
     --------------------------------------
    Date                 : Sun Sep 16 12:19:55 AKDT 2007
    Copyright            : (C) 2007 by Gary E. Sherman
    Email                : sherman at mrcc 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 QGSGMLSCHEMA_H
#define QGSGMLSCHEMA_H

#include <expat.h>
#include "qgis.h"
#include "qgsapplication.h"
#include "qgsdataprovider.h"
#include "qgserror.h"
#include "qgsfeature.h"
#include "qgsfield.h"
#include "qgslogger.h"
#include "qgspoint.h"
#include <list>
#include <set>
#include <stack>
#include <QPair>
#include <QByteArray>
#include <QDomElement>
#include <QStringList>
#include <QStack>
class QgsRectangle;
class QgsCoordinateReferenceSystem;

/* Description of feature class in GML */
class CORE_EXPORT QgsGmlFeatureClass
{
  public:
    QgsGmlFeatureClass( );
    QgsGmlFeatureClass( QString name, QString path );

    ~QgsGmlFeatureClass();

    QList<QgsField> & fields() { return  mFields; }

    int fieldIndex( const QString & name );

    QString path() const { return mPath; }

    QStringList & geometryAttributes() { return mGeometryAttributes; }

  private:
    /* Feature class name:
     *  - element name without NS or known prefix/suffix (_feature)
     *  - typeName attribute name */
    QString mName;

    //QString mElementName;

    /* Dot separated path to element including the name */
    QString mPath;

    /* Fields */
    // Do not use QMap to keep original fields order. If it gets to performance,
    // add a field index map
    QList<QgsField> mFields;

    /* Geometry attribute */
    QStringList mGeometryAttributes;
};

class CORE_EXPORT QgsGmlSchema : public QObject
{
    Q_OBJECT
  public:
    QgsGmlSchema();

    ~QgsGmlSchema();

    bool parseXSD( const QByteArray &xml );

    bool guessSchema( const QByteArray &data );

    QStringList typeNames() const;

    QList<QgsField> fields( const QString & typeName );

    QStringList geometryAttributes( const QString & typeName );

    QgsError error() const { return mError; }

  private:

    enum ParseMode
    {
      none,
      boundingBox,
      featureMembers, // gml:featureMembers
      featureMember, // gml:featureMember
      feature,  // feature element containint attrs and geo (inside gml:featureMember)
      attribute,
      geometry
    };

    void startElement( const XML_Char* el, const XML_Char** attr );
    void endElement( const XML_Char* el );
    void characters( const XML_Char* chars, int len );
    static void start( void* data, const XML_Char* el, const XML_Char** attr )
    {
      static_cast<QgsGmlSchema*>( data )->startElement( el, attr );
    }
    static void end( void* data, const XML_Char* el )
    {
      static_cast<QgsGmlSchema*>( data )->endElement( el );
    }
    static void chars( void* data, const XML_Char* chars, int len )
    {
      static_cast<QgsGmlSchema*>( data )->characters( chars, len );
    }

    //helper routines

    QString readAttribute( const QString& attributeName, const XML_Char** attr ) const;

    QWidget* findMainWindow() const;

    QList<QDomElement> domElements( const QDomElement &element, const QString & path );

    QDomElement domElement( const QDomElement &element, const QString & path );

    QList<QDomElement> domElements( QList<QDomElement> &elements, const QString & attr, const QString & attrVal );

    QDomElement domElement( const QDomElement &element, const QString & path, const QString & attr, const QString & attrVal );

    QString stripNS( const QString & name );

    QString xsdComplexTypeGmlBaseType( const QDomElement &element, const QString & name );

    bool xsdFeatureClass( const QDomElement &element, const QString & typeName, QgsGmlFeatureClass & featureClass );


    ParseMode modeStackTop() { return mParseModeStack.isEmpty() ? none : mParseModeStack.top(); }

    ParseMode modeStackPop() { return mParseModeStack.isEmpty() ? none : mParseModeStack.pop(); }

    //std::stack<ParseMode> mParseModeStack;
    QStack<ParseMode> mParseModeStack;
    QString mStringCash;
    QgsFeature* mCurrentFeature;
    QString mCurrentFeatureId;
    int mFeatureCount;
    QString mAttributeName;
    QString mCoordinateSeparator;
    QString mTupleSeparator;

    /* Schema information guessed/parsed from GML in getSchema() */

    int mLevel;

    int mSkipLevel;

    QStringList mParsePathStack;

    QString mCurrentFeatureName;

    // List of know geometries (Point, Multipoint,...)
    QStringList mGeometryTypes;

    /* Feature classes map with element paths as keys */
    QMap<QString, QgsGmlFeatureClass> mFeatureClassMap;

    /* Error set if something failed */
    QgsError mError;
};

#endif