roadmap_metadata.c

/* roadmap_metadata.c - Manage the map metadata information.
 *
 * LICENSE:
 *
 *   Copyright 2002 Pascal F. Martin
 *
 *   This file is part of RoadMap.
 *
 *   RoadMap 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.
 *
 *   RoadMap is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with RoadMap; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * SYNOPSYS:
 *
 *   const char *roadmap_metadata_get_attribute (const char *category,
 *                                               const char *name);
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

#include "roadmap.h"
#include "roadmap_dictionary.h"
#include "roadmap_metadata.h"
#include "roadmap_tile_model.h"

#include "roadmap_db_metadata.h"


static const char *RoadMapMetadataType = "RoadMapMetadataContext";

typedef struct {

   const char *type;

   RoadMapAttribute *Attributes;
   int               AttributesCount;

   RoadMapDictionary RoadMapAttributeStrings;

} RoadMapMetadataContext;

static RoadMapMetadataContext *RoadMapMetadataActive = NULL;


static void *roadmap_metadata_map (const roadmap_db_data_file *file) {

   RoadMapMetadataContext *context;

   context = (RoadMapMetadataContext *) malloc (sizeof(RoadMapMetadataContext));
   if (context == NULL) {
      roadmap_log (ROADMAP_ERROR, "no more memory");
      return NULL;
   }
   context->type = RoadMapMetadataType;
   context->RoadMapAttributeStrings = NULL;

   if (!roadmap_db_get_data (file,
   								  model__tile_metadata_attributes,
   								  sizeof (RoadMapAttribute),
   								  (void**)&(context->Attributes),
   								  &(context->AttributesCount))) {
      roadmap_log (ROADMAP_ERROR, "invalid metadata/attributes structure");
      goto roadmap_metadata_map_abort;
   }

   return context;

roadmap_metadata_map_abort:

   free(context);
   return NULL;
}

static void roadmap_metadata_activate (void *context) {

   RoadMapMetadataContext *this = (RoadMapMetadataContext *) context;

   if (this != NULL) {

      if (this->type != RoadMapMetadataType) {
         roadmap_log (ROADMAP_FATAL, "invalid metadata context activated");
      }

      if (this->RoadMapAttributeStrings == NULL) {
         this->RoadMapAttributeStrings =
            roadmap_dictionary_open ("attributes");
      }

      if (this->RoadMapAttributeStrings == NULL) {
         roadmap_log (ROADMAP_FATAL, "cannot open dictionary");
      }
   }

   RoadMapMetadataActive = this;
}

static void roadmap_metadata_unmap (void *context) {

   RoadMapMetadataContext *this = (RoadMapMetadataContext *) context;

   if (this->type != RoadMapMetadataType) {
      roadmap_log (ROADMAP_FATAL, "unmapping invalid line context");
   }
   if (RoadMapMetadataActive == this) {
      RoadMapMetadataActive = NULL;
   }
   free (this);
}

roadmap_db_handler RoadMapMetadataHandler = {
   "metadata",
   roadmap_metadata_map,
   roadmap_metadata_activate,
   roadmap_metadata_unmap
};


const char *roadmap_metadata_get_attribute (const char *category,
                                            const char *name) {

   int i;

   if (RoadMapMetadataActive == NULL) return "";

   for (i = RoadMapMetadataActive->AttributesCount - 1; i >= 0; --i) {

	   const char *attr_category = 
	   	roadmap_dictionary_get (RoadMapMetadataActive->RoadMapAttributeStrings, RoadMapMetadataActive->Attributes[i].category);
	   const char *attr_name = 
	   	roadmap_dictionary_get (RoadMapMetadataActive->RoadMapAttributeStrings, RoadMapMetadataActive->Attributes[i].name);

      if (strcmp (name, attr_name) == 0 &&
          strcmp (category, attr_category) == 0) {
         return roadmap_dictionary_get
                   (RoadMapMetadataActive->RoadMapAttributeStrings,
                    RoadMapMetadataActive->Attributes[i].value);
      }
   }
   return "";
}