/******************************************************************************
 * $Id: ogrdxf_blockmap.cpp 23668 2011-12-30 21:44:47Z rouault $
 *
 * Project:  DXF Translator
 * Purpose:  Implements BlockMap reading and management portion of 
 *           OGRDXFDataSource class
 * Author:   Frank Warmerdam, warmerdam@pobox.com
 *
 ******************************************************************************
 * Copyright (c) 2009, Frank Warmerdam <warmerdam@pobox.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.
 ****************************************************************************/

#include "ogr_dxf.h"
#include "cpl_conv.h"
#include "cpl_string.h"
#include "cpl_csv.h"

CPL_CVSID("$Id: ogrdxf_blockmap.cpp 23668 2011-12-30 21:44:47Z rouault $");

/************************************************************************/
/*                          ReadBlockSection()                          */
/************************************************************************/

void OGRDXFDataSource::ReadBlocksSection()

{
    char szLineBuf[257];
    int  nCode;
    OGRDXFLayer *poReaderLayer = (OGRDXFLayer *) GetLayerByName( "Entities" );
    int bMergeBlockGeometries = CSLTestBoolean(
        CPLGetConfigOption( "DXF_MERGE_BLOCK_GEOMETRIES", "TRUE" ) );

    iEntitiesSectionOffset = oReader.iSrcBufferFileOffset + oReader.iSrcBufferOffset;

    while( (nCode = ReadValue( szLineBuf, sizeof(szLineBuf) )) > -1 
           && !EQUAL(szLineBuf,"ENDSEC") )
    {
        // We are only interested in extracting blocks.
        if( nCode != 0 || !EQUAL(szLineBuf,"BLOCK") )
            continue;

        // Process contents of BLOCK definition till we find the 
        // first entity.
        CPLString osBlockName;

        while( (nCode = ReadValue( szLineBuf,sizeof(szLineBuf) )) > 0 )
        {
            if( nCode == 2 )
                osBlockName = szLineBuf;

            // anything else we want? 
        }

        if( EQUAL(szLineBuf,"ENDBLK") )
            continue;

        if (nCode >= 0)
            UnreadValue();

        // Now we will process entities till we run out at the ENDBLK code.
        // we aggregate the geometries of the features into a multi-geometry,
        // but throw away other stuff attached to the features.

        OGRFeature *poFeature;
        OGRGeometryCollection *poColl = new OGRGeometryCollection();
        std::vector<OGRFeature*> apoFeatures;

        while( (poFeature = poReaderLayer->GetNextUnfilteredFeature()) != NULL )
        {
            if( (poFeature->GetStyleString() != NULL
                 && strstr(poFeature->GetStyleString(),"LABEL") != NULL)
                || !bMergeBlockGeometries )
            {
                apoFeatures.push_back( poFeature );
            }
            else
            {
                poColl->addGeometryDirectly( poFeature->StealGeometry() );
                delete poFeature;
            }
        }

        if( poColl->getNumGeometries() == 0 )
            delete poColl;
        else
            oBlockMap[osBlockName].poGeometry = SimplifyBlockGeometry(poColl);

        if( apoFeatures.size() > 0 )
            oBlockMap[osBlockName].apoFeatures = apoFeatures;
    }

    CPLDebug( "DXF", "Read %d blocks with meaningful geometry.", 
              (int) oBlockMap.size() );
}

/************************************************************************/
/*                       SimplifyBlockGeometry()                        */
/************************************************************************/

OGRGeometry *OGRDXFDataSource::SimplifyBlockGeometry( 
    OGRGeometryCollection *poCollection )

{
/* -------------------------------------------------------------------- */
/*      If there is only one geometry in the collection, just return    */
/*      it.                                                             */
/* -------------------------------------------------------------------- */
    if( poCollection->getNumGeometries() == 1 )
    {
        OGRGeometry *poReturn = poCollection->getGeometryRef(0);
        poCollection->removeGeometry(0,FALSE);
        delete poCollection;
        return poReturn;
    }

/* -------------------------------------------------------------------- */
/*      Eventually we likely ought to have logic to convert to          */
/*      polygon, multipolygon, multilinestring or multipoint but        */
/*      I'll put that off till it would be meaningful.                  */
/* -------------------------------------------------------------------- */
    
    return poCollection;
}

/************************************************************************/
/*                            LookupBlock()                             */
/*                                                                      */
/*      Find the geometry collection corresponding to a name if it      */
/*      exists.  Note that the returned geometry pointer is to a        */
/*      geometry that continues to be owned by the datasource.  It      */
/*      should be cloned for use.                                       */
/************************************************************************/

DXFBlockDefinition *OGRDXFDataSource::LookupBlock( const char *pszName )

{
    CPLString osName = pszName;

    if( oBlockMap.count( osName ) == 0 )
        return NULL;
    else
        return &(oBlockMap[osName]);
}

/************************************************************************/
/*                        ~DXFBlockDefinition()                         */
/*                                                                      */
/*      Safe cleanup of a block definition.                             */
/************************************************************************/

DXFBlockDefinition::~DXFBlockDefinition()

{
    delete poGeometry;

    while( !apoFeatures.empty() )
    {
        delete apoFeatures.back();
        apoFeatures.pop_back();
    }
}
