/****************************************************************************
*
* MODULE:       Vector library 
*   	    	
* AUTHOR(S):    Radim Blazek, Piero Cavalieri 
*
* PURPOSE:      Higher level functions for reading/writing/manipulating vectors.
*
* COPYRIGHT:    (C) 2001 by the GRASS Development Team
*
*               This program is free software under the GNU General Public
*   	    	License (>=v2). Read the file COPYING that comes with GRASS
*   	    	for details.
*
*****************************************************************************/
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <grass/Vect.h>
#include <grass/gis.h>

#ifdef HAVE_OGR
#include <ogr_api.h>

/* Open old file.
*  Map->name and Map->mapset must be set before
*
*  Return: 0 success
*         -1 error
*/
int
V1_open_old_ogr (struct Map_info *Map, int update)
{
    int i, layer, nLayers;
    OGRDataSourceH Ogr_ds;
    OGRLayerH Ogr_layer=NULL;
    OGRFeatureDefnH Ogr_featuredefn;

    if (update) {
	G_warning ("OGR format cannot be updated.");
	return -1;
    }

    G_debug (2, "V1_open_old_ogr(): dsn = %s layer = %s", Map->fInfo.ogr.dsn,
	     Map->fInfo.ogr.layer_name);

    OGRRegisterAll ();

    /*Data source handle */
    Ogr_ds = OGROpen (Map->fInfo.ogr.dsn, FALSE, NULL);
    if (Ogr_ds == NULL)
	G_fatal_error ("Cannot open OGR data source '%s'", Map->fInfo.ogr.dsn);
    Map->fInfo.ogr.ds = Ogr_ds;

    /* Layer number */
    layer = -1;
    nLayers = OGR_DS_GetLayerCount (Ogr_ds);
    G_debug (2, "%d layers found in data source", nLayers);

    for (i = 0; i < nLayers; i++) {
	Ogr_layer = OGR_DS_GetLayer (Ogr_ds, i);
	Ogr_featuredefn = OGR_L_GetLayerDefn (Ogr_layer);
	if ( strcmp( OGR_FD_GetName (Ogr_featuredefn), Map->fInfo.ogr.layer_name) == 0) {
	    layer = i;
	    break;
	}
    }
    if (layer == -1) {
	OGR_DS_Destroy (Ogr_ds);
	G_fatal_error ("Cannot open layer '%s'", Map->fInfo.ogr.layer_name);
    }
    G_debug (2, "OGR layer %d opened", layer);

    Map->fInfo.ogr.layer = Ogr_layer;

    Map->fInfo.ogr.lines = NULL;
    Map->fInfo.ogr.lines_types = NULL;
    Map->fInfo.ogr.lines_alloc = 0;
    Map->fInfo.ogr.lines_num = 0;
    Map->fInfo.ogr.lines_next = 0;

    Map->head.with_z = WITHOUT_Z; /* TODO: 3D */

    Map->fInfo.ogr.feature_cache = NULL;
    Map->fInfo.ogr.feature_cache_id = -1; /* FID >= 0 */

    return (0);
}

/* Open OGR specific level 2 files (feature index).
*
*  Return: 0 success
*         -1 error
*/
int
V2_open_old_ogr (struct Map_info *Map )
{
    char elem[1000];
    char buf[5];
    long length; 
    GVFILE fp;
    struct Port_info port;
    int Version_Major, Version_Minor, Back_Major, Back_Minor, byte_order;
	
    G_debug (3, "V2_open_old_ogr()" );
    
    sprintf (elem, "%s/%s", GRASS_VECT_DIRECTORY, Map->name);
    dig_file_init ( &fp );
    fp.file = G_fopen_old ( elem, "fidx", Map->mapset);
    if ( fp.file ==  NULL) {
	G_warning("Can't open fidx file for vector '%s@%s'.", Map->name, Map->mapset);
	return -1;
    }
    
    /* Header */
    if (0 >= dig__fread_port_C (buf, 5, &fp))  return (-1);
    Version_Major = buf[0];
    Version_Minor = buf[1];
    Back_Major    = buf[2];
    Back_Minor    = buf[3];
    byte_order    = buf[4];


    /* check version numbers */
    if ( Version_Major > 5 || Version_Minor > 0 ) {
        if ( Back_Major > 5 || Back_Minor > 0 ) {
            G_fatal_error ( "Feature index format version %d.%d is not supported by this release."
                            " Try to rebuild topology or upgrade GRASS.", Version_Major, Version_Minor);
            return (-1);
        }
        G_warning ( "Your GRASS version does not fully support feature index format %d.%d of the vector."
	            " Consider to rebuild topology or upgrade GRASS.",
                    Version_Major, Version_Minor );
    }

    dig_init_portable ( &port, byte_order );
    dig_set_cur_port ( &port );

    /* Body */
    /* bytes 6 - 9 : header size */
    if (0 >= dig__fread_port_L (&length, 1, &fp)) return (-1);
    G_debug (3, "  header size %d", length );
    
    fseek ( fp.file, length, SEEK_SET);
    
    /* number of records  */
    if (0 >= dig__fread_port_I (&(Map->fInfo.ogr.offset_num), 1, &fp)) return (-1);

    /* alloc space */
    Map->fInfo.ogr.offset = (int *) G_malloc ( Map->fInfo.ogr.offset_num * sizeof(int) );
    Map->fInfo.ogr.offset_alloc = Map->fInfo.ogr.offset_num;

    /* offsets */
    if (0 >= dig__fread_port_I ( Map->fInfo.ogr.offset, 
				 Map->fInfo.ogr.offset_num, &fp)) return (-1);

    fclose( fp.file );

    G_debug (3, "%d records read from fidx", Map->fInfo.ogr.offset_num );


    Map->fInfo.ogr.next_line = 1;

    return 0;
}

#endif