/******************************************************************************

 *

 * Project:  GDAL/OGR Geography Network support (Geographic Network Model)

 * Purpose:  GNM general public declarations.

 * Authors:  Mikhail Gusev (gusevmihs at gmail dot com)

 *           Dmitry Baryshnikov, polimax@mail.ru

 *

 ******************************************************************************

 * Copyright (c) 2014, Mikhail Gusev

 * Copyright (c) 2014-2015, NextGIS <info@nextgis.com>

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the "Software"),

 * to deal in the Software without restriction, including without limitation

 * the rights to use, copy, modify, merge, publish, distribute, sublicense,

 * and/or sell copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included

 * in all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER

 * DEALINGS IN THE SOFTWARE.

 ****************************************************************************/

#ifndef GNM

#define GNM

#if defined(__cplusplus) && !defined(CPL_SUPRESS_CPLUSPLUS)

#include "ogrsf_frmts.h"

#endif

#include "gnmgraph.h"

// Direction of an edge.

typedef int GNMDirection;  // We use int values in order to save them to the

                           // network data.

// Network's metadata parameters names.

#define GNM_MD_NAME "net_name"

#define GNM_MD_DESCR "net_description"

#define GNM_MD_SRS "net_srs"

#define GNM_MD_VERSION "net_version"

#define GNM_MD_RULE "net_rule"

#define GNM_MD_FORMAT "FORMAT"

#define GNM_MD_FETCHEDGES "fetch_edge"

#define GNM_MD_FETCHVERTEX "fetch_vertex"

#define GNM_MD_NUM_PATHS "num_paths"

#define GNM_MD_EMITTER "emitter"

// TODO: Constants for capabilities.

// #define GNMCanChangeConnections "CanChangeConnections"

typedef enum

{

    /** Dijkstra shortest path */ GATDijkstraShortestPath = 1,

    /** KShortest Paths        */ GATKShortestPath,

    /** Recursive Breadth-first search */ GATConnectedComponents

} GNMGraphAlgorithmType;

#if defined(__cplusplus) && !defined(CPL_SUPRESS_CPLUSPLUS)

/**

 * General GNM class which represents a geography network of common format.

 *

 * @since GDAL 2.1

 */

class CPL_DLL GNMNetwork : public GDALDataset

{

  public:

    GNMNetwork();

    virtual ~GNMNetwork();

    // GDALDataset Interface

    const OGRSpatialReference *GetSpatialRef() const override;

    virtual char **GetFileList(void) override;

    // GNMNetwork Interface

    /**

     * @brief Create network system layers

     *

     * Creates the connectivity (the "network path" of data) over the dataset

     * and returns the resulting network.

     * NOTE: This method does not create any connections among features

     * but creates the necessary set of fields, layers, etc.

     * NOTE: After the successful creation the passed dataset must not be

     * modified outside (but can be read as usual).

     * NOTE: For the common network format the creation is forbidden if the

     * passed dataset already has network system layers and OVERWRITE creation

     * option is FALSE.

     *

     * @param pszFilename - A path there the network folder (schema, etc.) will

     *                      be created. The folder (schema, etc.) name get

     *                      options.

     * @param papszOptions - create network options. The create options

     *                       specific for gnm driver.

     * @return CE_None on success

     */

    virtual CPLErr Create(const char *pszFilename, char **papszOptions) = 0;

    /**

     * @brief Open a network

     * @param poOpenInfo GDALOpenInfo pointer

     * @return CE_None on success

     */

    virtual CPLErr Open(GDALOpenInfo *poOpenInfo) = 0;

    /**

     * @brief Delete network. Delete all dependent layers

     * @return CE_None on success

     */

    virtual CPLErr Delete() = 0;

    /**

     * @brief GetName - a network name. The value provided to create function

     *        in GNM_MD_NAME key. While creation this value used to create the

     *        folder or db schema name. But can be changed after creation.

     * @return Network name string

     */

    virtual const char *GetName() const;

    /**

     * @brief GetVersion return the network version if applicable

     * @return version value

     */

    virtual int GetVersion() const

    {

        return 0;

    }

    /**

     * @brief DisconnectAll method clears the network graph

     * @return CE_None on success

     */

    virtual CPLErr DisconnectAll() = 0;

    /**

     * @brief GetFeatureByGlobalFID search all network layers for given feature

     *        identificator.

     * @param nGFID feature identificator.

     * @return OGRFeature pointer or NULL. The pointer should be freed via

     *         OGRFeature::DestroyFeature().

     */

    virtual OGRFeature *GetFeatureByGlobalFID(GNMGFID nGFID) = 0;

    /**

     * @brief Create path between start and end GFIDs.

     * @param nStartFID - start identificator

     * @param nEndFID - end identificator

     * @param eAlgorithm - The algorithm to get path

     * @param papszOptions - algorithm specific options

     * @return In memory OGRLayer pointer with features constituting

     *         the shortest path (or paths). The caller have to free

     *         the pointer via @see ReleaseResultSet().

     */

    virtual OGRLayer *GetPath(GNMGFID nStartFID, GNMGFID nEndFID,

                              GNMGraphAlgorithmType eAlgorithm,

                              char **papszOptions) = 0;

    /** Casts a handle to a pointer */

    static inline GNMNetwork *FromHandle(GNMGenericNetworkH hNet)

    {

        return static_cast<GNMNetwork *>(hNet);

    }

    /** Casts a pointer to a handle */

    static inline GNMGenericNetworkH ToHandle(GNMNetwork *poNetwork)

    {

        return static_cast<GNMGenericNetworkH>(poNetwork);

    }

  protected:

    /**

     * @brief Check if network already exist

     * @param pszFilename - path to network (folder or database

     * @param papszOptions - create options

     * @return TRUE if exist and not overwrite or FALSE

     */

    virtual int CheckNetworkExist(const char *pszFilename,

                                  char **papszOptions) = 0;

  protected:

    //! @cond Doxygen_Suppress

    CPLString m_soName{};

    OGRSpatialReference m_oSRS{};

    //! @endcond

};

class GNMRule;

class OGRGNMWrappedResultLayer;

/**

 * GNM class which represents a geography network of generic format.

 *

 * @since GDAL 2.1

 */

class CPL_DLL GNMGenericNetwork : public GNMNetwork

{

  public:

    GNMGenericNetwork();

    virtual ~GNMGenericNetwork();

    // GDALDataset Interface

    virtual int GetLayerCount() override;

    virtual OGRLayer *GetLayer(int) override;

    virtual OGRErr DeleteLayer(int) override;

    virtual int TestCapability(const char *) override;

    virtual OGRLayer *CopyLayer(OGRLayer *poSrcLayer, const char *pszNewName,

                                char **papszOptions = nullptr) override;

    virtual int CloseDependentDatasets() override;

    virtual CPLErr FlushCache(bool bAtClosing) override;

    // GNMNetwork Interface

    virtual CPLErr Create(const char *pszFilename,

                          char **papszOptions) override = 0;

    virtual CPLErr Delete() override;

    virtual int GetVersion() const override;

    /**

     * @brief GetNewGlobalFID increase the global ID counter.

     * @return New global feature ID.

     */

    virtual GNMGFID GetNewGlobalFID();

    /**

     * @brief Get the algorithm name

     * @param eAlgorithm GNM algorithm type

     * @param bShortName Indicator which name to return - short or long

     * @return String with algorithm name

     */

    virtual CPLString GetAlgorithmName(GNMDirection eAlgorithm,

                                       bool bShortName);

    /**

     * @brief AddFeatureGlobalFID add the FID <-> Layer name link to fast access

     *        features by global FID.

     * @param nFID - global FID

     * @param pszLayerName - layer name

     * @return CE_None on success

     */

    virtual CPLErr AddFeatureGlobalFID(GNMGFID nFID, const char *pszLayerName);

    /**

     * @brief Connects two features via third feature (may be virtual, so the

     *        identificator should be -1). The features may be at the same layer

     *        or different layers.

     * @param nSrcFID - source feature identificator

     * @param nTgtFID - target feature identificator

     * @param nConFID - connection feature identificator (-1 for virtual

     * connection)

     * @param dfCost - cost moving from source to target (default 1)

     * @param dfInvCost - cost moving from target to source (default 1)

     * @param eDir - direction, may be source to target, target to source or

     * both. (default - both)

     * @return CE_None on success

     */

    virtual CPLErr ConnectFeatures(GNMGFID nSrcFID, GNMGFID nTgtFID,

                                   GNMGFID nConFID = -1, double dfCost = 1,

                                   double dfInvCost = 1,

                                   GNMDirection eDir = GNM_EDGE_DIR_BOTH);

    /**

     * @brief Remove features connection

     * @param nSrcFID - source feature identificator

     * @param nTgtFID - target feature identificator

     * @param nConFID - connection feature identificator

     * @return CE_None on success

     */

    virtual CPLErr DisconnectFeatures(GNMGFID nSrcFID, GNMGFID nTgtFID,

                                      GNMGFID nConFID);

    /**

     * @brief Find the corresponding identificator in graph (source, target,

     *        connector) and remove such connections.

     * @param nFID - identificator to find.

     * @return CE_None on success

     */

    virtual CPLErr DisconnectFeaturesWithId(GNMGFID nFID);

    /**

     * @brief Change connection attributes. Search the connection by source

     *        feature identificator, target feature identificator and connection

     *        identificator.

     * @param nSrcFID - source feature identificator

     * @param nTgtFID - target feature identificator

     * @param nConFID - connection feature identificator

     * @param dfCost - new cost moving from source to target

     * @param dfInvCost - new cost moving from target to source

     * @param eDir - new direction

     * @return CE_None on success

     */

    virtual CPLErr ReconnectFeatures(GNMGFID nSrcFID, GNMGFID nTgtFID,

                                     GNMGFID nConFID, double dfCost = 1,

                                     double dfInvCost = 1,

                                     GNMDirection eDir = GNM_EDGE_DIR_BOTH);

    virtual CPLErr DisconnectAll() override;

    virtual OGRFeature *GetFeatureByGlobalFID(GNMGFID nFID) override;

    /**

     * @brief Create network rule

     *

     * Creates the rule in the network according to the special syntax. These

     * rules are declarative and make an effect for the network when they exist.

     * Each rule for layer can be created only if the corresponding layer

     * existed and removed when the layer is being deleted.

     *

     * Rules syntax for the common network format in GNM contains the key words

     * (words in capital letters or signs) and the modifiers which refers to the

     * network objects. All the following combinations are available:

     *

     *  Notation:

     *  layer1, layer2, layer3 - a layer names (the corresponding layers must be

     *                           exist;

     *  field1 - a field name (field must be exist);

     *  constant1 - any double constant;

     *  string1 - any string;

     *

     *  Rules describing which layer can be connected or not connected with each

     *  other, and (optional) which layer must serve as a connector. By default

     *  all connections are forbidden. But while network creation process the

     *  rule to allow any connection added. During the connection process each

     *  rule tested if this connection can be created.

     *

     *    "ALLOW CONNECTS ANY"

     *    "DENY CONNECTS ANY"

     *    "DENY CONNECTS layer1 WITH layer2"

     *    "ALLOW CONNECTS layer1 WITH layer2 VIA layer3"

     *

     * @param pszRuleStr Rule string which will parsed. If the parsing was

     *        successful, the rule will start having effect immediately.

     * @return CE_None on success.

     */

    virtual CPLErr CreateRule(const char *pszRuleStr);

    /**

     * @brief Delete all rules from network

     * @return CE_None on success.

     */

    virtual CPLErr DeleteAllRules();

    /**

     * @brief Delete the specified rule

     * @param pszRuleStr - the rule to delete

     * @return CE_None on success.

     */

    virtual CPLErr DeleteRule(const char *pszRuleStr);

    /**

     * @brief Get the rule list

     * @return list of rule strings. The caller have to free the lis via

     * CPLDestroy.

     */

    virtual char **GetRules() const;

    /**

     * @brief Attempts to build the network topology automatically

     *

     * The method simply gets point and line or multiline layers from the

     * papszLayerList and searches for each line which connects two points:

     * start and end, so it can be not so effective in performance when it is

     * called on huge networks. Note, when passing your tolerance value: this

     * value will depend of spatial reference system of the network, and

     * especially of its 0,0 position because dfTolerance is just divided by 2

     * and added/subtracted to/from both sides of each line-feature end point

     * forming thus the square area around it. The first point-feature occurred

     * inside this area will be given as a start/end point for the current

     * connection. So it is also desirable that at least two layers are passed

     * in papszLayerList (one point and one line), and they are already

     * connected "visually" ("geometrically").

     *

     * @param papszLayerList A list of layers to connect. The list should be

     *                       freed via CSLDestroy.

     * @param dfTolerance Snapping tolerance.

     * @param dfCost Direct cost.

     * @param dfInvCost Inverse cost.

     * @param eDir Direction.

     * @return CE_None on success

     */

    virtual CPLErr ConnectPointsByLines(char **papszLayerList,

                                        double dfTolerance, double dfCost,

                                        double dfInvCost, GNMDirection eDir);

    /**

     * @brief Change the block state of edge or vertex

     * @param nFID Identificator

     * @param bIsBlock Block or unblock

     * @return CE_None on success

     */

    virtual CPLErr ChangeBlockState(GNMGFID nFID, bool bIsBlock);

    /**

     * @brief Change all vertices and edges block state.

     *

     * This is mainly use for unblock all vertices and edges.

     *

     * @param bIsBlock Block or unblock

     * @return CE_None on success

     */

    virtual CPLErr ChangeAllBlockState(bool bIsBlock = false);

    virtual OGRLayer *GetPath(GNMGFID nStartFID, GNMGFID nEndFID,

                              GNMGraphAlgorithmType eAlgorithm,

                              char **papszOptions) override;

    /** Casts a handle to a pointer */

    static inline GNMGenericNetwork *FromHandle(GNMGenericNetworkH hNet)

    {

        return static_cast<GNMGenericNetwork *>(hNet);

    }

    /** Casts a pointer to a handle */

    static inline GNMGenericNetworkH ToHandle(GNMGenericNetwork *poNetwork)

    {

        return static_cast<GNMGenericNetworkH>(poNetwork);

    }

  protected:

    /**

     * @brief Check or create layer OGR driver

     * @param pszDefaultDriverName - default driver name

     * @param papszOptions - create options

     * @return CE_None if driver is exist or CE_Failure

     */

    virtual CPLErr CheckLayerDriver(const char *pszDefaultDriverName,

                                    char **papszOptions);

    /**

     * @brief Check if provided OGR driver accepted as storage for network data

     * @param pszDriverName The driver name

     * @return true if supported, else false

     */

    virtual bool CheckStorageDriverSupport(const char *pszDriverName) = 0;

  protected:

    //! @cond Doxygen_Suppress

    virtual CPLErr CreateMetadataLayer(GDALDataset *const pDS, int nVersion,

                                       size_t nFieldSize = 1024);

    virtual CPLErr StoreNetworkSrs();

    virtual CPLErr LoadNetworkSrs();

    virtual CPLErr CreateGraphLayer(GDALDataset *const pDS);

    virtual CPLErr CreateFeaturesLayer(GDALDataset *const pDS);

    virtual CPLErr LoadMetadataLayer(GDALDataset *const pDS);

    virtual CPLErr LoadGraphLayer(GDALDataset *const pDS);

    virtual CPLErr LoadGraph();

    virtual CPLErr LoadFeaturesLayer(GDALDataset *const pDS);

    virtual CPLErr DeleteMetadataLayer() = 0;

    virtual CPLErr DeleteGraphLayer() = 0;

    virtual CPLErr DeleteFeaturesLayer() = 0;

    virtual CPLErr LoadNetworkLayer(const char *pszLayername) = 0;

    virtual CPLErr DeleteNetworkLayers() = 0;

    virtual void ConnectPointsByMultiline(

        GIntBig nFID, const OGRMultiLineString *poMultiLineString,

        const std::vector<OGRLayer *> &paPointLayers, double dfTolerance,

        double dfCost, double dfInvCost, GNMDirection eDir);

    virtual void

    ConnectPointsByLine(GIntBig nFID, const OGRLineString *poLineString,

                        const std::vector<OGRLayer *> &paPointLayers,

                        double dfTolerance, double dfCost, double dfInvCost,

                        GNMDirection eDir);

    virtual GNMGFID

    FindNearestPoint(const OGRPoint *poPoint,

                     const std::vector<OGRLayer *> &paPointLayers,

                     double dfTolerance);

    virtual OGRFeature *FindConnection(GNMGFID nSrcFID, GNMGFID nTgtFID,

                                       GNMGFID nConFID);

    virtual bool SaveRules();

    virtual GNMGFID GetNewVirtualFID();

    virtual void FillResultLayer(OGRGNMWrappedResultLayer *poResLayer,

                                 const GNMPATH &path, int nNoOfPath,

                                 bool bReturnVertices, bool bReturnEdges);

    //! @endcond

  protected:

    //! @cond Doxygen_Suppress

    int m_nVersion = 0;

    GNMGFID m_nGID = 0;

    GNMGFID m_nVirtualConnectionGID = -1;

    OGRLayer *m_poMetadataLayer = nullptr;

    OGRLayer *m_poGraphLayer = nullptr;

    OGRLayer *m_poFeaturesLayer = nullptr;

    GDALDriver *m_poLayerDriver = nullptr;

    std::map<GNMGFID, CPLString> m_moFeatureFIDMap{};

    std::vector<OGRLayer *> m_apoLayers{};

    std::vector<GNMRule> m_asRules{};

    bool m_bIsRulesChanged = false;

    GNMGraph m_oGraph{};

    bool m_bIsGraphLoaded = false;

    //! @endcond

  private:

    CPL_DISALLOW_COPY_ASSIGN(GNMGenericNetwork)

};

/**

 * GNM layer which represents a geography network layer of generic format.

 * The class override some OGRLayer methods to fulfill the network requirements.

 *

 * @since GDAL 2.1

 */

class GNMGenericLayer : public OGRLayer

{

  public:

    GNMGenericLayer(OGRLayer *poLayer, GNMGenericNetwork *poNetwork);

    virtual ~GNMGenericLayer();

    // OGRLayer Interface

    virtual OGRGeometry *GetSpatialFilter() override;

    virtual OGRErr ISetSpatialFilter(int iGeomField,

                                     const OGRGeometry *) override;

    virtual OGRErr SetAttributeFilter(const char *) override;

    virtual void ResetReading() override;

    virtual OGRFeature *GetNextFeature() override;

    virtual OGRErr SetNextByIndex(GIntBig nIndex) override;

    virtual OGRErr DeleteFeature(GIntBig nFID) override;

    virtual const char *GetName() override;

    virtual OGRwkbGeometryType GetGeomType() override;

    virtual OGRFeatureDefn *GetLayerDefn() override;

    virtual int FindFieldIndex(const char *pszFieldName,

                               int bExactMatch) override;

    virtual OGRSpatialReference *GetSpatialRef() override;

    virtual GIntBig GetFeatureCount(int bForce = TRUE) override;

    virtual OGRErr IGetExtent(int iGeomField, OGREnvelope *psExtent,

                              bool bForce = true) override;

    virtual int TestCapability(const char *) override;

    virtual OGRErr CreateField(const OGRFieldDefn *poField,

                               int bApproxOK = TRUE) override;

    virtual OGRErr DeleteField(int iField) override;

    virtual OGRErr ReorderFields(int *panMap) override;

    virtual OGRErr AlterFieldDefn(int iField, OGRFieldDefn *poNewFieldDefn,

                                  int nFlagsIn) override;

    virtual OGRErr CreateGeomField(const OGRGeomFieldDefn *poField,

                                   int bApproxOK = TRUE) override;

    virtual OGRErr SyncToDisk() override;

    virtual OGRStyleTable *GetStyleTable() override;

    virtual void SetStyleTableDirectly(OGRStyleTable *poStyleTable) override;

    virtual void SetStyleTable(OGRStyleTable *poStyleTable) override;

    virtual OGRErr StartTransaction() override;

    virtual OGRErr CommitTransaction() override;

    virtual OGRErr RollbackTransaction() override;

    virtual const char *GetFIDColumn() override;

    virtual const char *GetGeometryColumn() override;

    virtual OGRErr SetIgnoredFields(CSLConstList papszFields) override;

    /** Intersection */

    OGRErr Intersection(OGRLayer *pLayerMethod, OGRLayer *pLayerResult,

                        char **papszOptions = nullptr,

                        GDALProgressFunc pfnProgress = nullptr,

                        void *pProgressArg = nullptr);

    /** Union */

    OGRErr Union(OGRLayer *pLayerMethod, OGRLayer *pLayerResult,

                 char **papszOptions = nullptr,

                 GDALProgressFunc pfnProgress = nullptr,

                 void *pProgressArg = nullptr);

    /** SymDifference */

    OGRErr SymDifference(OGRLayer *pLayerMethod, OGRLayer *pLayerResult,

                         char **papszOptions, GDALProgressFunc pfnProgress,

                         void *pProgressArg);

    /** Identity */

    OGRErr Identity(OGRLayer *pLayerMethod, OGRLayer *pLayerResult,

                    char **papszOptions = nullptr,

                    GDALProgressFunc pfnProgress = nullptr,

                    void *pProgressArg = nullptr);

    /** Update */

    OGRErr Update(OGRLayer *pLayerMethod, OGRLayer *pLayerResult,

                  char **papszOptions = nullptr,

                  GDALProgressFunc pfnProgress = nullptr,

                  void *pProgressArg = nullptr);

    /** Clip */

    OGRErr Clip(OGRLayer *pLayerMethod, OGRLayer *pLayerResult,

                char **papszOptions = nullptr,

                GDALProgressFunc pfnProgress = nullptr,

                void *pProgressArg = nullptr);

    /** Erase */

    OGRErr Erase(OGRLayer *pLayerMethod, OGRLayer *pLayerResult,

                 char **papszOptions = nullptr,

                 GDALProgressFunc pfnProgress = nullptr,

                 void *pProgressArg = nullptr);

    /** GetFeaturesRead */

    GIntBig GetFeaturesRead();

    /** AttributeFilterEvaluationNeedsGeometry */

    int AttributeFilterEvaluationNeedsGeometry();

    //! @cond Doxygen_Suppress

    /* consider these private */

    OGRErr InitializeIndexSupport(const char *);

    OGRLayerAttrIndex *GetIndex();

    //! @endcond

  protected:

    //! @cond Doxygen_Suppress

    virtual OGRErr ISetFeature(OGRFeature *poFeature) override;

    virtual OGRErr ICreateFeature(OGRFeature *poFeature) override;

  protected:

    CPLString m_soLayerName{};

    OGRLayer *m_poLayer = nullptr;

    GNMGenericNetwork *m_poNetwork = nullptr;

    std::map<GNMGFID, GIntBig> m_mnFIDMap{};

    //! @endcond

  private:

    CPL_DISALLOW_COPY_ASSIGN(GNMGenericLayer)

};

typedef enum

{

    /** Rule for connect features */ GRTConnection = 0

} GNMRuleType;

/**

 * @brief The simple class for rules

 *

 * By now we have only connect rules, so the one class is enough. Maybe in

 * future the set of classes for different rule types will be needed.

 *

 * @since GDAL 2.1

 */

class CPL_DLL GNMRule

{

  public:

    /** Constructor */

    GNMRule();

    /** Constructor */

    explicit GNMRule(const std::string &oRule);

    /** Constructor */

    explicit GNMRule(const char *pszRule);

    /** Copy constructor */

    GNMRule(const GNMRule &) = default;

    /** Move constructor */

    GNMRule(GNMRule &&) = default;

    /** Assignment operator */

    GNMRule &operator=(const GNMRule &) = default;

    /** Move assignment operator */

    GNMRule &operator=(GNMRule &&) = default;

    /** Destructor */

    virtual ~GNMRule();

    /**

     * @brief  This function indicate if rule string was parsed successfully

     * @return true if rule is valid

     */

    virtual bool IsValid() const;

    /**

     * @brief Indicator of any layer state

     * @return true if accept any layer

     */

    virtual bool IsAcceptAny() const;

    /**

     * @brief This is for future use to indicate the rule type/ Now return only

     * GRTConnection type.

     * @return the rule type

     */

    virtual GNMRuleType GetType() const;

    /**

     * @brief Check if connection can take place.

     * @param soSrcLayerName - the layer name

     * @param soTgtLayerName - the layer name

     * @param soConnLayerName - the layer name

     * @return true if can connect features from soSrcLayerName and

     * soTgtLayerName via soConnLayerName

     */

    virtual bool CanConnect(const CPLString &soSrcLayerName,

                            const CPLString &soTgtLayerName,

                            const CPLString &soConnLayerName = "");

    /** Return source layer name */

    virtual CPLString GetSourceLayerName() const;

    /** Return target layer name */

    virtual CPLString GetTargetLayerName() const;

    /** Return connector layer name */

    virtual CPLString GetConnectorLayerName() const;

    /** Return rule as a string */

    const char *c_str() const;

    /** Return rule as a string */

    operator const char *(void) const;

  protected:

    //! @cond Doxygen_Suppress

    virtual bool ParseRuleString();

  protected:

    CPLString m_soSrcLayerName{};

    CPLString m_soTgtLayerName{};

    CPLString m_soConnLayerName{};

    bool m_bAllow = false;

    bool m_bValid = false;

    bool m_bAny = false;

    CPLString m_soRuleString{};

    //! @endcond

};

/**

 * @brief The OGRGNMWrappedResultLayer class for search paths queries results.

 *

 * @since GDAL 2.1

 */

class OGRGNMWrappedResultLayer : public OGRLayer

{

  public:

    OGRGNMWrappedResultLayer(GDALDataset *poDS, OGRLayer *poLayer);

    ~OGRGNMWrappedResultLayer();

    // OGRLayer

    virtual void ResetReading() override;

    virtual OGRFeature *GetNextFeature() override;

    virtual OGRErr SetNextByIndex(GIntBig nIndex) override;

    virtual OGRFeature *GetFeature(GIntBig nFID) override;

    virtual OGRFeatureDefn *GetLayerDefn() override;

    virtual GIntBig GetFeatureCount(int bForce = TRUE) override;

    virtual int TestCapability(const char *pszCap) override;

    virtual OGRErr CreateField(const OGRFieldDefn *poField,

                               int bApproxOK = TRUE) override;

    virtual OGRErr CreateGeomField(const OGRGeomFieldDefn *poField,

                                   int bApproxOK = TRUE) override;

    virtual const char *GetFIDColumn() override;

    virtual const char *GetGeometryColumn() override;

    virtual OGRSpatialReference *GetSpatialRef() override;

    // OGRGNMWrappedResultLayer

    virtual OGRErr InsertFeature(OGRFeature *poFeature,

                                 const CPLString &soLayerName, int nPathNo,

                                 bool bIsEdge);

  protected:

    virtual OGRErr ISetFeature(OGRFeature *poFeature) override;

    virtual OGRErr ICreateFeature(OGRFeature *poFeature) override;

  protected:

    //! @cond Doxygen_Suppress

    GDALDataset *poDS = nullptr;

    OGRLayer *poLayer = nullptr;

    //! @endcond

  private:

    CPL_DISALLOW_COPY_ASSIGN(OGRGNMWrappedResultLayer)

};

#endif  // __cplusplus

#endif  // GNM