/******************************************************************************
 * $Id: ogr2gmlgeometry.cpp,v 1.6 2003/04/17 08:22:06 dron Exp $
 *
 * Project:  GML Translator
 * Purpose:  Code to translate OGRGeometry to GML string representation.
 * Author:   Frank Warmerdam, warmerdam@pobox.com
 *
 ******************************************************************************
 * Copyright (c) 2002, 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.
 *****************************************************************************
 *
 * Independent Security Audit 2003/04/17 Andrey Kiselev:
 *   Completed audit of this module. All functions may be used without buffer
 *   overflows and stack corruptions if caller could be trusted.
 *
 * Security Audit 2003/03/28 warmerda:
 *   Completed security audit.  I believe that this module may be safely used 
 *   to generate GML from arbitrary but well formed OGRGeomety objects that
 *   come from a potentially hostile source, but through a trusted OGR importer
 *   without compromising the system.
 *
 * $Log: ogr2gmlgeometry.cpp,v $
 * Revision 1.6  2003/04/17 08:22:06  dron
 * Completed secutity audit, fix in MakeGMLCoordinate().
 *
 * Revision 1.5  2003/03/28 06:00:14  warmerda
 * Completed security audit.  Fixed issue with very large coordinate values
 * potentially causing a buffer overrun.
 *
 * Revision 1.4  2003/03/18 17:13:03  warmerda
 * Improve precision (and use %g) for latlong coordinates.
 *
 * Revision 1.3  2003/03/12 20:52:07  warmerda
 * implemented support for gml:Box
 *
 * Revision 1.2  2003/03/07 21:30:15  warmerda
 * expand tabs
 *
 * Revision 1.1  2003/03/06 20:28:38  warmerda
 * Migrated to here (gdal/ogr) from gdal/ogr/ogrsf_frmts/gml.
 * Changed to implement the C API entry points (OGR_G_*).
 * Added API to take/return CPLXMLNode's directly.
 *
 * Revision 1.5  2002/03/11 22:34:08  warmerda
 * Avoid multiple defining iMember.
 *
 * Revision 1.4  2002/03/11 17:29:04  warmerda
 * added multipolygon support
 *
 * Revision 1.3  2002/03/07 22:38:04  warmerda
 * use ogr_gml_geom.h
 *
 * Revision 1.2  2002/01/25 21:00:31  warmerda
 * fix some small bugs found by MS VC++
 *
 * Revision 1.1  2002/01/25 20:37:02  warmerda
 * New
 */

#include "cpl_minixml.h"
#include "ogr_geometry.h"
#include "ogr_api.h"
#include "cpl_error.h"
#include "cpl_conv.h"

/************************************************************************/
/*                        MakeGMLCoordinate()                           */
/************************************************************************/

static void MakeGMLCoordinate( char *pszTarget, 
                               double x, double y, double z, int b3D )

{
    if( !b3D )
    {
        if( x == (int) x && y == (int) y )
            sprintf( pszTarget, "%d,%d", (int) x, (int) y );
        else if( fabs(x) < 370 && fabs(y) < 370 )
            sprintf( pszTarget, "%.16g,%.16g", x, y );
        else if( fabs(x) > 100000000.0 || fabs(y) > 100000000.0 )
            sprintf( pszTarget, "%.16g,%.16g", x, y );
        else
            sprintf( pszTarget, "%.3f,%.3f", x, y );
    }
    else
    {
        if( x == (int) x && y == (int) y && z == (int) z )
            sprintf( pszTarget, "%d,%d,%d", (int) x, (int) y, (int) z );
        else if( fabs(x) < 370 && fabs(y) < 370 )
            sprintf( pszTarget, "%.16g,%.16g,%.16g", x, y, z );
        else if( fabs(x) > 100000000.0 || fabs(y) > 100000000.0 
                 || fabs(z) > 100000000.0 )
            sprintf( pszTarget, "%.16g,%.16g,%.16g", x, y, z );
        else
            sprintf( pszTarget, "%.3f,%.3f,%.3f", x, y, z );
    }
}

/************************************************************************/
/*                            _GrowBuffer()                             */
/************************************************************************/

static void _GrowBuffer( int nNeeded, char **ppszText, int *pnMaxLength )

{
    if( nNeeded+1 >= *pnMaxLength )
    {
        *pnMaxLength = MAX(*pnMaxLength * 2,nNeeded+1);
        *ppszText = (char *) CPLRealloc(*ppszText, *pnMaxLength);
    }
}

/************************************************************************/
/*                            AppendString()                            */
/************************************************************************/

static void AppendString( char **ppszText, int *pnLength, int *pnMaxLength,
                          const char *pszTextToAppend )

{
    _GrowBuffer( *pnLength + strlen(pszTextToAppend) + 1, 
                 ppszText, pnMaxLength );

    strcat( *ppszText + *pnLength, pszTextToAppend );
    *pnLength += strlen( *ppszText + *pnLength );
}


/************************************************************************/
/*                        AppendCoordinateList()                        */
/************************************************************************/

static void AppendCoordinateList( OGRLineString *poLine, 
                                  char **ppszText, int *pnLength, 
                                  int *pnMaxLength )

{
    char        szCoordinate[256];
    int         b3D = (poLine->getGeometryType() & 0x8000);

    *pnLength += strlen(*ppszText + *pnLength);
    _GrowBuffer( *pnLength + 20, ppszText, pnMaxLength );

    strcat( *ppszText + *pnLength, "<gml:coordinates>" );
    *pnLength += strlen(*ppszText + *pnLength);

    
    for( int iPoint = 0; iPoint < poLine->getNumPoints(); iPoint++ )
    {
        MakeGMLCoordinate( szCoordinate, 
                           poLine->getX(iPoint),
                           poLine->getY(iPoint),
                           poLine->getZ(iPoint),
                           b3D );
        _GrowBuffer( *pnLength + strlen(szCoordinate)+1, 
                     ppszText, pnMaxLength );

        if( iPoint != 0 )
            strcat( *ppszText + *pnLength, " " );
            
        strcat( *ppszText + *pnLength, szCoordinate );
        *pnLength += strlen(*ppszText + *pnLength);
    }
    
    _GrowBuffer( *pnLength + 20, ppszText, pnMaxLength );
    strcat( *ppszText + *pnLength, "</gml:coordinates>" );
    *pnLength += strlen(*ppszText + *pnLength);
}

/************************************************************************/
/*                       OGR2GMLGeometryAppend()                        */
/************************************************************************/

static int OGR2GMLGeometryAppend( OGRGeometry *poGeometry, 
                                  char **ppszText, int *pnLength, 
                                  int *pnMaxLength )

{
/* -------------------------------------------------------------------- */
/*      2D Point                                                        */
/* -------------------------------------------------------------------- */
    if( poGeometry->getGeometryType() == wkbPoint )
    {
        char    szCoordinate[256];
        OGRPoint *poPoint = (OGRPoint *) poGeometry;

        MakeGMLCoordinate( szCoordinate, 
                           poPoint->getX(), poPoint->getY(), 0.0, FALSE );
                           
        _GrowBuffer( *pnLength + strlen(szCoordinate) + 60, 
                     ppszText, pnMaxLength );

        sprintf( *ppszText + *pnLength, 
                "<gml:Point><gml:coordinates>%s</gml:coordinates></gml:Point>",
                 szCoordinate );

        *pnLength += strlen( *ppszText + *pnLength );
    }
/* -------------------------------------------------------------------- */
/*      3D Point                                                        */
/* -------------------------------------------------------------------- */
    else if( poGeometry->getGeometryType() == wkbPoint25D )
    {
        char    szCoordinate[256];
        OGRPoint *poPoint = (OGRPoint *) poGeometry;

        MakeGMLCoordinate( szCoordinate, 
                           poPoint->getX(), poPoint->getY(), poPoint->getZ(), 
                           TRUE );
                           
        _GrowBuffer( *pnLength + strlen(szCoordinate) + 70, 
                     ppszText, pnMaxLength );

        sprintf( *ppszText + *pnLength, 
                "<gml:Point><gml:coordinates>%s</gml:coordinates></gml:Point>",
                 szCoordinate );

        *pnLength += strlen( *ppszText + *pnLength );
    }

/* -------------------------------------------------------------------- */
/*      LineString and LinearRing                                       */
/* -------------------------------------------------------------------- */
    else if( poGeometry->getGeometryType() == wkbLineString 
             || poGeometry->getGeometryType() == wkbLineString25D )
    {
        int bRing = EQUAL(poGeometry->getGeometryName(),"LINEARRING");

        if( bRing )
            AppendString( ppszText, pnLength, pnMaxLength,
                          "<gml:LinearRing>" );
        else
            AppendString( ppszText, pnLength, pnMaxLength,
                          "<gml:LineString>" );

        AppendCoordinateList( (OGRLineString *) poGeometry, 
                              ppszText, pnLength, pnMaxLength );
        
        if( bRing )
            AppendString( ppszText, pnLength, pnMaxLength,
                          "</gml:LinearRing>" );
        else
            AppendString( ppszText, pnLength, pnMaxLength,
                          "</gml:LineString>" );
    }

/* -------------------------------------------------------------------- */
/*      Polygon                                                         */
/* -------------------------------------------------------------------- */
    else if( poGeometry->getGeometryType() == wkbPolygon 
             || poGeometry->getGeometryType() == wkbPolygon25D )
    {
        OGRPolygon      *poPolygon = (OGRPolygon *) poGeometry;

        AppendString( ppszText, pnLength, pnMaxLength,
                      "<gml:Polygon>" );

        if( poPolygon->getExteriorRing() != NULL )
        {
            AppendString( ppszText, pnLength, pnMaxLength,
                          "<gml:outerBoundaryIs>" );

            if( !OGR2GMLGeometryAppend( poPolygon->getExteriorRing(), 
                                        ppszText, pnLength, pnMaxLength ) )
                return FALSE;
            
            AppendString( ppszText, pnLength, pnMaxLength,
                          "</gml:outerBoundaryIs>" );
        }

        for( int iRing = 0; iRing < poPolygon->getNumInteriorRings(); iRing++ )
        {
            OGRLinearRing *poRing = poPolygon->getInteriorRing(iRing);

            AppendString( ppszText, pnLength, pnMaxLength,
                          "<gml:innerBoundaryIs>" );
            
            if( !OGR2GMLGeometryAppend( poRing, ppszText, pnLength, 
                                        pnMaxLength ) )
                return FALSE;
            
            AppendString( ppszText, pnLength, pnMaxLength,
                          "</gml:innerBoundaryIs>" );
        }

        AppendString( ppszText, pnLength, pnMaxLength,
                      "</gml:Polygon>" );
    }

/* -------------------------------------------------------------------- */
/*      MultiPolygon                                                    */
/* -------------------------------------------------------------------- */
    else if( poGeometry->getGeometryType() == wkbMultiPolygon 
             || poGeometry->getGeometryType() == wkbMultiPolygon25D )
    {
        OGRMultiPolygon *poMPoly = (OGRMultiPolygon *) poGeometry;
        int             iMember;

        AppendString( ppszText, pnLength, pnMaxLength,
                      "<gml:MultiPolygon>" );

        for( iMember = 0; iMember < poMPoly->getNumGeometries(); iMember++)
        {
            OGRGeometry *poMember = poMPoly->getGeometryRef( iMember );

            AppendString( ppszText, pnLength, pnMaxLength,
                          "<gml:polygonMember>" );
            
            if( !OGR2GMLGeometryAppend( poMember, 
                                        ppszText, pnLength, pnMaxLength ) )
                return FALSE;
            
            AppendString( ppszText, pnLength, pnMaxLength,
                          "</gml:polygonMember>" );
        }

        AppendString( ppszText, pnLength, pnMaxLength,
                      "</gml:MultiPolygon>" );
    }
    else
        return FALSE;

    return TRUE;
}

/************************************************************************/
/*                   OGR_G_ExportEnvelopeToGMLTree()                    */
/*                                                                      */
/*      Export the envelope of a geometry as a gml:Box.                 */
/************************************************************************/

CPLXMLNode *OGR_G_ExportEnvelopeToGMLTree( OGRGeometryH hGeometry )

{
    CPLXMLNode *psBox, *psCoord;
    OGREnvelope sEnvelope;
    char        szCoordinate[256];
    char       *pszY;

    memset( &sEnvelope, 0, sizeof(sEnvelope) );
    ((OGRGeometry *) hGeometry)->getEnvelope( &sEnvelope );

    if( sEnvelope.MinX == 0 && sEnvelope.MaxX == 0 
        && sEnvelope.MaxX == 0 && sEnvelope.MaxY == 0 )
    {
        /* there is apparently a special way of representing a null box
           geometry ... we should use it here eventually. */

        return NULL;
    }

    psBox = CPLCreateXMLNode( NULL, CXT_Element, "gml:Box" );

/* -------------------------------------------------------------------- */
/*      Add minxy coordinate.                                           */
/* -------------------------------------------------------------------- */
    psCoord = CPLCreateXMLNode( psBox, CXT_Element, "gml:coord" );
    
    MakeGMLCoordinate( szCoordinate, sEnvelope.MinX, sEnvelope.MinY, 0.0, 
                       FALSE );
    pszY = strstr(szCoordinate,",") + 1;
    pszY[-1] = '\0';

    CPLCreateXMLElementAndValue( psCoord, "gml:X", szCoordinate );
    CPLCreateXMLElementAndValue( psCoord, "gml:Y", pszY );

/* -------------------------------------------------------------------- */
/*      Add maxxy coordinate.                                           */
/* -------------------------------------------------------------------- */
    psCoord = CPLCreateXMLNode( psBox, CXT_Element, "gml:coord" );
    
    MakeGMLCoordinate( szCoordinate, sEnvelope.MaxX, sEnvelope.MaxY, 0.0, 
                       FALSE );
    pszY = strstr(szCoordinate,",") + 1;
    pszY[-1] = '\0';

    CPLCreateXMLElementAndValue( psCoord, "gml:X", szCoordinate );
    CPLCreateXMLElementAndValue( psCoord, "gml:Y", pszY );

    return psBox;
}

/************************************************************************/
/*                       OGR_G_ExportToGMLTree()                        */
/************************************************************************/

CPLXMLNode *OGR_G_ExportToGMLTree( OGRGeometryH hGeometry )

{
    char        *pszText;
    CPLXMLNode  *psTree;

    pszText = OGR_G_ExportToGML( hGeometry );
    if( pszText == NULL )
        return NULL;

    psTree = CPLParseXMLString( pszText );

    CPLFree( pszText );

    return psTree;
}

/************************************************************************/
/*                         OGR_G_ExportToGML()                          */
/************************************************************************/

char *OGR_G_ExportToGML( OGRGeometryH hGeometry )

{
    char        *pszText;
    int         nLength = 0, nMaxLength = 1;

    if( hGeometry == NULL )
        return CPLStrdup( "" );

    pszText = (char *) CPLMalloc(nMaxLength);
    pszText[0] = '\0';

    if( !OGR2GMLGeometryAppend( (OGRGeometry *) hGeometry, &pszText, 
                                &nLength, &nMaxLength ))
    {
        CPLFree( pszText );
        return NULL;
    }
    else
        return pszText;
}
