/* Implements the mid-layer processing for osm2pgsql
 * using several PostgreSQL tables
 * 
 * This layer stores data read in from the planet.osm file
 * and is then read by the backend processing code to
 * emit the final geometry-enabled output formats
*/

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <errno.h>

#ifdef HAVE_PTHREAD
#include <pthread.h>
#endif

#include <libpq-fe.h>

#include "osmtypes.h"
#include "output.h"
#include "reprojection.h"
#include "output-pgsql.h"
#include "build_geometry.h"
#include "middle.h"
#include "pgsql.h"
#include "expire-tiles.h"

#define SRID (project_getprojinfo()->srs)

/* FIXME: Shouldn't malloc this all to begin with but call realloc()
   as required. The program will most likely segfault if it reads a
   style file with more styles than this */
#define MAX_STYLES 1000

enum table_id {
    t_point, t_line, t_poly, t_roads
};

static const struct output_options *Options;

/* Tables to output */
static struct s_table {
    //enum table_id table;
    char *name;
    const char *type;
    PGconn *sql_conn;
    char buffer[1024];
    unsigned int buflen;
    int copyMode;
    char *columns;
} tables [] = {
    { name: "%s_point",   type: "POINT"     },
    { name: "%s_line",    type: "LINESTRING"},
    { name: "%s_polygon", type: "POLYGON"  },
    { name: "%s_roads",   type: "LINESTRING"}
};
#define NUM_TABLES ((signed)(sizeof(tables) / sizeof(tables[0])))

#define FLAG_POLYGON 1    /* For polygon table */
#define FLAG_LINEAR  2    /* For lines table */
#define FLAG_NOCACHE 4    /* Optimisation: don't bother remembering this one */
#define FLAG_DELETE  8    /* These tags should be simply deleted on sight */
#define FLAG_IGNORE  16   /* Store value of tag only *if* object is stored */
static struct flagsname {
    char *name;
    int flag;
} tagflags[] = {
    { name: "polygon",    flag: FLAG_POLYGON },
    { name: "linear",     flag: FLAG_LINEAR },
    { name: "nocache",    flag: FLAG_NOCACHE },
    { name: "delete",     flag: FLAG_DELETE },
    { name: "ignore",     flag: FLAG_IGNORE }
};
#define NUM_FLAGS ((signed)(sizeof(tagflags) / sizeof(tagflags[0])))

/* Table columns, representing key= tags */
struct taginfo {
    char *name;
    char *type;
    int flags;
    int count;
};

static struct taginfo *exportList[4]; /* Indexed by enum table_id */
static int exportListCount[4];

/* Data to generate z-order column and road table
 * The name of the roads table is misleading, this table
 * is used for any feature to be shown at low zoom.
 * This includes railways and administrative boundaries too
 */
static struct {
    int offset;
    const char *highway;
    int roads;
} layers[] = {
    { 3, "minor",         0 },
    { 3, "road",          0 },
    { 3, "unclassified",  0 },
    { 3, "residential",   0 },
    { 4, "tertiary_link", 0 },
    { 4, "tertiary",      0 },
   // 5 = railway
    { 6, "secondary_link",1 },
    { 6, "secondary",     1 },
    { 7, "primary_link",  1 },
    { 7, "primary",       1 },
    { 8, "trunk_link",    1 },
    { 8, "trunk",         1 },
    { 9, "motorway_link", 1 },
    { 9, "motorway",      1 }
};
static const unsigned int nLayers = (sizeof(layers)/sizeof(*layers));

static int pgsql_delete_way_from_output(int osm_id);
static int pgsql_delete_relation_from_output(int osm_id);
static int pgsql_process_relation(int id, struct member *members, int member_count, struct keyval *tags, int exists);

void read_style_file( const char *filename )
{
  FILE *in;
  int lineno = 0;

  exportList[OSMTYPE_NODE] = malloc( sizeof(struct taginfo) * MAX_STYLES );
  exportList[OSMTYPE_WAY]  = malloc( sizeof(struct taginfo) * MAX_STYLES );

  in = fopen( filename, "rt" );
  if( !in )
  {
    fprintf( stderr, "Couldn't open style file '%s': %s\n", filename, strerror(errno) );
    exit_nicely();
  }
  
  char buffer[1024];
  while( fgets( buffer, sizeof(buffer), in) != NULL )
  {
    lineno++;
    
    char osmtype[24];
    char tag[24];
    char datatype[24];
    char flags[128];
    int i;
    char *str;

    str = strchr( buffer, '#' );
    if( str )
      *str = '\0';
      
    int fields = sscanf( buffer, "%23s %23s %23s %127s", osmtype, tag, datatype, flags );
    if( fields <= 0 )  /* Blank line */
      continue;
    if( fields < 3 )
    {
      fprintf( stderr, "Error reading style file line %d (fields=%d)\n", lineno, fields );
      exit_nicely();
    }
    struct taginfo temp;
    temp.name = strdup(tag);
    temp.type = strdup(datatype);
    
    temp.flags = 0;
    for( str = strtok( flags, ",\r\n" ); str; str = strtok(NULL, ",\r\n") )
    {
      for( i=0; i<NUM_FLAGS; i++ )
      {
        if( strcmp( tagflags[i].name, str ) == 0 )
        {
          temp.flags |= tagflags[i].flag;
          break;
        }
      }
      if( i == NUM_FLAGS )
        fprintf( stderr, "Unknown flag '%s' line %d, ignored\n", str, lineno );
    }
    temp.count = 0;
//    printf("%s %s %d %d\n", temp.name, temp.type, temp.polygon, offset );
    
    int flag = 0;
    if( strstr( osmtype, "node" ) )
    {
      memcpy( &exportList[ OSMTYPE_NODE ][ exportListCount[ OSMTYPE_NODE ] ], &temp, sizeof(temp) );
      exportListCount[ OSMTYPE_NODE ]++;
      flag = 1;
    }
    if( strstr( osmtype, "way" ) )
    {
      memcpy( &exportList[ OSMTYPE_WAY ][ exportListCount[ OSMTYPE_WAY ] ], &temp, sizeof(temp) );
      exportListCount[ OSMTYPE_WAY ]++;
      flag = 1;
    }
    if( !flag )
    {
      fprintf( stderr, "Weird style line %d\n", lineno );
      exit_nicely();
    }
  }
  fclose(in);
}

static void free_style_refs(const char *name, const char *type)
{
    // Find and remove any other references to these pointers
    // This would be way easier if we kept a single list of styles
    // Currently this scales with n^2 number of styles
    int i,j;

    for (i=0; i<NUM_TABLES; i++) {
        for(j=0; j<exportListCount[i]; j++) {
            if (exportList[i][j].name == name)
                exportList[i][j].name = NULL;
            if (exportList[i][j].type == type)
                exportList[i][j].type = NULL;
        }
    }
}

static void free_style(void)
{
    int i, j;
    for (i=0; i<NUM_TABLES; i++) {
        for(j=0; j<exportListCount[i]; j++) {
            free(exportList[i][j].name);
            free(exportList[i][j].type);
            free_style_refs(exportList[i][j].name, exportList[i][j].type);
        }
    }
    for (i=0; i<NUM_TABLES; i++)
        free(exportList[i]);
}

/* Handles copying out, but coalesces the data into large chunks for
 * efficiency. PostgreSQL doesn't actually need this, but each time you send
 * a block of data you get 5 bytes of overhead. Since we go column by column
 * with most empty and one byte delimiters, without this optimisation we
 * transfer three times the amount of data necessary.
 */
void copy_to_table(enum table_id table, const char *sql)
{
    PGconn *sql_conn = tables[table].sql_conn;
    unsigned int len = strlen(sql);
    unsigned int buflen = tables[table].buflen;
    char *buffer = tables[table].buffer;

    /* Return to copy mode if we dropped out */
    if( !tables[table].copyMode )
    {
        pgsql_exec(sql_conn, PGRES_COPY_IN, "COPY %s (%s,way) FROM STDIN", tables[table].name, tables[table].columns);
        tables[table].copyMode = 1;
    }
    /* If the combination of old and new data is too big, flush old data */
    if( (unsigned)(buflen + len) > sizeof( tables[table].buffer )-10 )
    {
      pgsql_CopyData(tables[table].name, sql_conn, buffer);
      buflen = 0;

      /* If new data by itself is also too big, output it immediately */
      if( (unsigned)len > sizeof( tables[table].buffer )-10 )
      {
        pgsql_CopyData(tables[table].name, sql_conn, sql);
        len = 0;
      }
    }
    /* Normal case, just append to buffer */
    if( len > 0 )
    {
      strcpy( buffer+buflen, sql );
      buflen += len;
      len = 0;
    }

    /* If we have completed a line, output it */
    if( buflen > 0 && buffer[buflen-1] == '\n' )
    {
      pgsql_CopyData(tables[table].name, sql_conn, buffer);
      buflen = 0;
    }

    tables[table].buflen = buflen;
}

static int add_z_order(struct keyval *tags, int *roads)
{
    const char *layer   = getItem(tags, "layer");
    const char *highway = getItem(tags, "highway");
    const char *bridge  = getItem(tags, "bridge");
    const char *tunnel  = getItem(tags, "tunnel");
    const char *railway = getItem(tags, "railway");
    const char *boundary= getItem(tags, "boundary");

    int z_order = 0;
    int l;
    unsigned int i;
    char z[13];

    l = layer ? strtol(layer, NULL, 10) : 0;
    z_order = 10 * l;
    *roads = 0;

    if (highway) {
        for (i=0; i<nLayers; i++) {
            if (!strcmp(layers[i].highway, highway)) {
                z_order += layers[i].offset;
                *roads   = layers[i].roads;
                break;
            }
        }
    }

    if (railway && strlen(railway)) {
        z_order += 5;
        *roads = 1;
    }
    // Administrative boundaries are rendered at low zooms so we prefer to use the roads table
    if (boundary && !strcmp(boundary, "administrative"))
        *roads = 1;

    if (bridge && (!strcmp(bridge, "true") || !strcmp(bridge, "yes") || !strcmp(bridge, "1")))
        z_order += 10;

    if (tunnel && (!strcmp(tunnel, "true") || !strcmp(tunnel, "yes") || !strcmp(tunnel, "1")))
        z_order -= 10;

    snprintf(z, sizeof(z), "%d", z_order);
    addItem(tags, "z_order", z, 0);

    return 0;
}


static void fix_motorway_shields(struct keyval *tags)
{
    const char *highway = getItem(tags, "highway");
    const char *name    = getItem(tags, "name");
    const char *ref     = getItem(tags, "ref");

    /* The current mapnik style uses ref= for motorway shields but some roads just have name= */
    if (!highway || strcmp(highway, "motorway"))
        return;

    if (name && !ref)
        addItem(tags, "ref", name, 0);
}


/* Append all alternate name:xx on to the name tag with space sepatators.
 * name= always comes first, the alternates are in no particular order
 * Note: A new line may be better but this does not work with Mapnik
 *
 *    <tag k="name" v="Ben Nevis" />
 *    <tag k="name:gd" v="Ben Nibheis" />
 * becomes:
 *    <tag k="name" v="Ben Nevis Ben Nibheis" />
 */
void compress_tag_name(struct keyval *tags)
{
    const char *name = getItem(tags, "name");
    struct keyval *name_ext = getMatches(tags, "name:");
    struct keyval *p;
    char out[2048];

    if (!name_ext)
        return;

    out[0] = '\0';
    if (name) {
        strncat(out, name, sizeof(out)-1);
        strncat(out, " ", sizeof(out)-1);
    }
    while((p = popItem(name_ext)) != NULL) {
        /* Exclude name:source = "dicataphone" and duplicates */
        if (strcmp(p->key, "name:source") && !strstr(out, p->value)) {
            strncat(out, p->value, sizeof(out)-1);
            strncat(out, " ", sizeof(out)-1);
        }
        freeItem(p);
    }
    free(name_ext);

    // Remove trailing space
    out[strlen(out)-1] = '\0';
    //fprintf(stderr, "*** New name: %s\n", out);
    updateItem(tags, "name", out);
}



static void pgsql_out_cleanup(void)
{
    int i;

    for (i=0; i<NUM_TABLES; i++) {
        if (tables[i].sql_conn) {
            PQfinish(tables[i].sql_conn);
            tables[i].sql_conn = NULL;
        }
    }
}

/* Escape data appropriate to the type */
static void escape_type(char *sql, int len, const char *value, const char *type) {
    int items, from, to;

    if ( !strcmp(type, "int4") ) {
        /* For integers we take the first number, or the average if it's a-b */
        items = sscanf(value, "%d-%d", &from, &to);
        if ( items == 1 ) {
            sprintf(sql, "%d", from);
        } else if ( items == 2 ) {
            sprintf(sql, "%d", (from + to) / 2);
        } else {
            sprintf(sql, "\\N");
        }
    } else {
        escape(sql, len, value);
    }
}


/* example from: pg_dump -F p -t planet_osm gis
COPY planet_osm (osm_id, name, place, landuse, leisure, "natural", man_made, waterway, highway, railway, amenity, tourism, learning, building, bridge, layer, way) FROM stdin;
17959841        \N      \N      \N      \N      \N      \N      \N      bus_stop        \N      \N      \N      \N      \N      \N    -\N      0101000020E610000030CCA462B6C3D4BF92998C9B38E04940
17401934        The Horn        \N      \N      \N      \N      \N      \N      \N      \N      pub     \N      \N      \N      \N    -\N      0101000020E6100000C12FC937140FD5BFB4D2F4FB0CE04940
...

mine - 01 01000000 48424298424242424242424256427364
psql - 01 01000020 E6100000 30CCA462B6C3D4BF92998C9B38E04940
       01 01000020 E6100000 48424298424242424242424256427364
0x2000_0000 = hasSRID, following 4 bytes = srid, not supported by geos WKBWriter
Workaround - output SRID=4326;<WKB>
*/

static int pgsql_out_node(int id, struct keyval *tags, double node_lat, double node_lon)
{
    char sql[2048], *v;
    int i;

    expire_tiles_from_bbox(node_lon, node_lat, node_lon, node_lat);
    sprintf(sql, "%d\t", id);
    copy_to_table(t_point, sql);

    for (i=0; i < exportListCount[OSMTYPE_NODE]; i++) {
        if( exportList[OSMTYPE_NODE][i].flags & FLAG_DELETE )
            continue;
        if ((v = getItem(tags, exportList[OSMTYPE_NODE][i].name)))
        {
            escape_type(sql, sizeof(sql), v, exportList[OSMTYPE_NODE][i].type);
            exportList[OSMTYPE_NODE][i].count++;
        }
        else
            sprintf(sql, "\\N");

        copy_to_table(t_point, sql);
        copy_to_table(t_point, "\t");
    }

    sprintf(sql, "SRID=%d;POINT(%.15g %.15g)", SRID, node_lon, node_lat);
    copy_to_table(t_point, sql);
    copy_to_table(t_point, "\n");

    return 0;
}



static void write_wkts(int id, struct keyval *tags, const char *wkt, enum table_id table)
{
    int j;
    char sql[2048];
    const char*v;

    sprintf(sql, "%d\t", id);
    copy_to_table(table, sql);

    for (j=0; j < exportListCount[OSMTYPE_WAY]; j++) {
            if( exportList[OSMTYPE_WAY][j].flags & FLAG_DELETE )
                continue;
            if ((v = getItem(tags, exportList[OSMTYPE_WAY][j].name)))
            {
                exportList[OSMTYPE_WAY][j].count++;
                escape_type(sql, sizeof(sql), v, exportList[OSMTYPE_WAY][j].type);
            }
            else
                sprintf(sql, "\\N");

            copy_to_table(table, sql);
            copy_to_table(table, "\t");
    }

    sprintf(sql, "SRID=%d;", SRID);
    copy_to_table(table, sql);
    copy_to_table(table, wkt);
    copy_to_table(table, "\n");
}

void add_parking_node(int id, struct keyval *tags, double node_lat, double node_lon)
{
// insert into planet_osm_point(osm_id,name,amenity,way) select osm_id,name,amenity,centroid(way) from planet_osm_polygon where amenity='parking';
	const char *access  = getItem(tags, "access");
	const char *amenity = getItem(tags, "amenity");
	const char *name    = getItem(tags, "name");
	struct keyval nodeTags;
	
	if (!amenity || strcmp(amenity, "parking"))
		return;
        
	// Do not add a 'P' symbol if access is defined and something other than public.
	if (access && strcmp(access, "public"))
		return;

	initList(&nodeTags);
	addItem(&nodeTags, "amenity", amenity, 0);
	if (name)
		addItem(&nodeTags, "name",    name,    0);
	if (access)
		addItem(&nodeTags, "access",  access,    0);
	
	pgsql_out_node(id, &nodeTags, node_lat, node_lon);
	resetList(&nodeTags);
}

static int tag_indicates_polygon(enum OsmType type, const char *key)
{
    int i;

    if (!strcmp(key, "area"))
        return 1;

    for (i=0; i < exportListCount[type]; i++) {
        if( strcmp( exportList[type][i].name, key ) == 0 )
            return exportList[type][i].flags & FLAG_POLYGON;
    }

    return 0;
}

#define uint64_t long long unsigned int
static struct photo_s {
	enum OsmType type;
	uint64_t osmid;
	const char *flickr;
	const char *foursquare;
	const char *dopplr;
	const char *lastfm;
	const char *upcoming;
	const char *openplaques;
	const char *openlibrary;
} photos[] = {
#include "../flickr-data"
}, *photo_sorted[3];
static int photos_num[3];

static int photo_find_compare(const void *a, const void *b)
{
	const uint64_t *ap = a;
	const struct photo_s *bp = b;

	return *ap - bp->osmid;
}

/* Go through the given tags and determine the union of flags. Also remove
 * any tags from the list that we don't know about */
unsigned int pgsql_filter_tags(uint64_t id, enum OsmType type,
                struct keyval *tags, int *polygon)
{
    int i, filter = 1;
    int flags = 0;
    int add_area_tag = 0;
    char *wp;
    struct photo_s *pic;

    const char *area;
    struct keyval *item;
    struct keyval temp;
    initList(&temp);

    pic = bsearch(&id, photo_sorted[type], photos_num[type],
                    sizeof(*photos), photo_find_compare);
    if (pic) {
        addItem(tags, "flickr", pic->flickr, 0);
        addItem(tags, "foursquare", pic->foursquare, 0);
        addItem(tags, "dopplr", pic->dopplr, 0);
        addItem(tags, "lastfm", pic->lastfm, 0);
        addItem(tags, "upcoming", pic->upcoming, 0);
        addItem(tags, "openplaques", pic->openplaques, 0);
        addItem(tags, "openlibrary", pic->openlibrary, 0);
    }

    /* We used to only go far enough to determine if it's a polygon or not, but now we go through and filter stuff we don't need */
    while( (item = popItem(tags)) != NULL )
    {
        /* Discard natural=coastline tags (we render these from a shapefile instead) */
        if (!strcmp("natural",item->key) && !strcmp("coastline",item->value))
        {		
            freeItem( item );
            item = NULL;
            add_area_tag = 1; /* Allow named islands to appear as polygons */
            continue;
        }    

	if (!strncmp("wikipedia:", item->key, 10))
        {
            if (!getItem(tags, "url") && !getItem(&temp, "url"))
            {
                wp = malloc(strlen(item->value) + 50);
                sprintf(wp, "http://%s.wikipedia.org/wiki/%s",
                        item->key + 10, item->value);
                addItem(tags, "url", wp, 0);
                free(wp);
            }

            freeItem(item);
            continue;
        }

        for (i=0; i < exportListCount[type]; i++)
        {
            if( strcmp( exportList[type][i].name, item->key ) == 0 )
            {
                if( exportList[type][i].flags & FLAG_DELETE )
                {
                    freeItem( item );
                    item = NULL;
                    break;
                }

                if( !(exportList[type][i].flags & FLAG_IGNORE) )
                    filter = 0;

                flags |= exportList[type][i].flags;

                pushItem( &temp, item );
                item = NULL;
                break;
            }
        }
        if( i == exportListCount[type] )
        {
            freeItem( item );
            item = NULL;
        }
    }

    /* Move from temp list back to original list */
    while( (item = popItem(&temp)) != NULL )
        pushItem( tags, item );

    *polygon = flags & FLAG_POLYGON;

    /* Special case allowing area= to override anything else */
    if ((area = getItem(tags, "area"))) {
        if (!strcmp(area, "yes") || !strcmp(area, "true") ||!strcmp(area, "1"))
            *polygon = 1;
        else if (!strcmp(area, "no") || !strcmp(area, "false") || !strcmp(area, "0"))
            *polygon = 0;
    } else {
        /* If we need to force this as a polygon, append an area tag */
        if (add_area_tag) {
            addItem(tags, "area", "yes", 0);
            *polygon = 1;
        }
    }

    return filter;
}

/*
COPY planet_osm (osm_id, name, place, landuse, leisure, "natural", man_made, waterway, highway, railway, amenity, tourism, learning, bu
ilding, bridge, layer, way) FROM stdin;
198497  Bedford Road    \N      \N      \N      \N      \N      \N      residential     \N      \N      \N      \N      \N      \N    \N       0102000020E610000004000000452BF702B342D5BF1C60E63BF8DF49406B9C4D470037D5BF5471E316F3DF4940DFA815A6EF35D5BF9AE95E27F5DF4940B41EB
E4C1421D5BF24D06053E7DF4940
212696  Oswald Road     \N      \N      \N      \N      \N      \N      minor   \N      \N      \N      \N      \N      \N      \N    0102000020E610000004000000467D923B6C22D5BFA359D93EE4DF4940B3976DA7AD11D5BF84BBB376DBDF4940997FF44D9A06D5BF4223D8B8FEDF49404D158C4AEA04D
5BF5BB39597FCDF4940
*/
static int pgsql_out_way(int id, struct keyval *tags, struct osmNode *nodes, int count, int exists)
{
    int polygon = 0, roads = 0;
    char *wkt;
    double area, interior_lat, interior_lon;
    
    /* If the flag says this object may exist already, delete it first */
    if(exists)
        pgsql_delete_way_from_output(id);

    if (pgsql_filter_tags(id, OSMTYPE_WAY, tags, &polygon) || add_z_order(tags, &roads))
        return 0;

    //compress_tag_name(tags);

    fix_motorway_shields(tags);

    wkt = get_wkt_simple(nodes, count, polygon, &area, &interior_lon, &interior_lat);
    if (wkt && strlen(wkt)) {
	/* FIXME: there should be a better way to detect polygons */
	if (!strncmp(wkt, "POLYGON", strlen("POLYGON"))) {
            expire_tiles_from_nodes_poly(nodes, count, id);
	    if (area > 0.0) {
		char tmp[32];
		snprintf(tmp, sizeof(tmp), "%f", area);
		addItem(tags, "way_area", tmp, 0);
	    }
	    write_wkts(id, tags, wkt, t_poly);
	    //add_parking_node(id, tags, interior_lat, interior_lon);
	} else {
            expire_tiles_from_nodes_line(nodes, count);
	    write_wkts(id, tags, wkt, t_line);
	    if (roads)
		write_wkts(id, tags, wkt, t_roads);
	}
    }
    free(wkt);
	
    return 0;
}

static int pgsql_out_relation(int id, struct keyval *rel_tags, struct osmNode **xnodes, struct keyval *xtags, int *xcount, int *xid, const char **xrole)
{
    int i, wkt_size;
    double interior_lat, interior_lon;
    int polygon = 0, roads = 0;
    int make_polygon = 0;
    int make_boundary = 0;
    struct keyval tags, *p, poly_tags;
    char *type;
#if 0
    fprintf(stderr, "Got relation with counts:");
    for (i=0; xcount[i]; i++)
        fprintf(stderr, " %d", xcount[i]);
    fprintf(stderr, "\n");
#endif
    /* Get the type, if there's no type we don't care */
    type = getItem(rel_tags, "type");
    if( !type )
        return 0;

    initList(&tags);
    initList(&poly_tags);

    /* Clone tags from relation */
    p = rel_tags->next;
    while (p != rel_tags) {
        // For routes, we convert name to route_name
        if ((strcmp(type, "route") == 0) && (strcmp(p->key, "name") ==0))
            addItem(&tags, "route_name", p->value, 1);
        else if (strcmp(p->key, "type")) // drop type=
            addItem(&tags, p->key, p->value, 1);
        p = p->next;
    }

    if( strcmp(type, "route") == 0 )
    {
        const char *state = getItem(rel_tags, "state");
        const char *netw = getItem(rel_tags, "network");
        int networknr = -1;

        if (state == NULL) {
            state = "";
        }

        if (netw != NULL) {
            if (strcmp(netw, "lcn") == 0) {
                networknr = 10;
                if (strcmp(state, "alternate") == 0) {
                    addItem(&tags, "lcn", "alternate", 1);
                } else if (strcmp(state, "connection") == 0) {
                    addItem(&tags, "lcn", "connection", 1);
                } else {
                    addItem(&tags, "lcn", "yes", 1);
                }
            } else if (strcmp(netw, "rcn") == 0) {
                networknr = 11;
                if (strcmp(state, "alternate") == 0) {
                    addItem(&tags, "rcn", "alternate", 1);
                } else if (strcmp(state, "connection") == 0) {
                    addItem(&tags, "rcn", "connection", 1);
                } else {
                    addItem(&tags, "rcn", "yes", 1);
                }
            } else if (strcmp(netw, "ncn") == 0) {
                networknr = 12;
                if (strcmp(state, "alternate") == 0) {
                    addItem(&tags, "ncn", "alternate", 1);
                } else if (strcmp(state, "connection") == 0) {
                    addItem(&tags, "ncn", "connection", 1);
                } else {
                    addItem(&tags, "ncn", "yes", 1);
                }


            } else if (strcmp(netw, "lwn") == 0) {
                networknr = 20;
                if (strcmp(state, "alternate") == 0) {
                    addItem(&tags, "lwn", "alternate", 1);
                } else if (strcmp(state, "connection") == 0) {
                    addItem(&tags, "lwn", "connection", 1);
                } else {
                    addItem(&tags, "lwn", "yes", 1);
                }
            } else if (strcmp(netw, "rwn") == 0) {
                networknr = 21;
                if (strcmp(state, "alternate") == 0) {
                    addItem(&tags, "rwn", "alternate", 1);
                } else if (strcmp(state, "connection") == 0) {
                    addItem(&tags, "rwn", "connection", 1);
                } else {
                    addItem(&tags, "rwn", "yes", 1);
                }
            } else if (strcmp(netw, "nwn") == 0) {
                networknr = 22;
                if (strcmp(state, "alternate") == 0) {
                    addItem(&tags, "nwn", "alternate", 1);
                } else if (strcmp(state, "connection") == 0) {
                    addItem(&tags, "nwn", "connection", 1);
                } else {
                    addItem(&tags, "nwn", "yes", 1);
                }
            }
        }

        if (getItem(rel_tags, "preferred_color") != NULL) {
            const char *a = getItem(rel_tags, "preferred_color");
            if (strcmp(a, "0") == 0 || strcmp(a, "1") == 0 || strcmp(a, "2") == 0 || strcmp(a, "3") == 0 || strcmp(a, "4") == 0) {
                addItem(&tags, "route_pref_color", a, 1);
            } else {
                addItem(&tags, "route_pref_color", "0", 1);
            }
        } else {
            addItem(&tags, "route_pref_color", "0", 1);
        }

        if (getItem(rel_tags, "ref") != NULL) {
            if (networknr == 10) {
                addItem(&tags, "lcn_ref", getItem(rel_tags, "ref"), 1);
            } else if (networknr == 11) {
                addItem(&tags, "rcn_ref", getItem(rel_tags, "ref"), 1);
            } else if (networknr == 12) {
                addItem(&tags, "ncn_ref", getItem(rel_tags, "ref"), 1);
            } else if (networknr == 20) {
                addItem(&tags, "lwn_ref", getItem(rel_tags, "ref"), 1);
            } else if (networknr == 21) {
                addItem(&tags, "rwn_ref", getItem(rel_tags, "ref"), 1);
            } else if (networknr == 22) {
                addItem(&tags, "nwn_ref", getItem(rel_tags, "ref"), 1);
            }
        }
    }
    else if( strcmp( type, "multipolygon" ) == 0 )
    {
        make_polygon = 1;

        /* Copy the tags from the outer way(s) if the relation is untagged */
        /* or if there is just a name tag, people seem to like naming relations */
        if (!listHasData(&tags) || ((countList(&tags)==1) && getItem(&tags, "name"))) {
            for (i=0; xcount[i]; i++) {
                if (xrole[i] && !strcmp(xrole[i], "inner"))
                    continue;

                p = xtags[i].next;
                while (p != &(xtags[i])) {
                    addItem(&tags, p->key, p->value, 1);
                    p = p->next;
                }
            }
        }

        // Collect a list of polygon-like tags, these are used later to
        // identify if an inner rings looks like it should be rendered seperately
        p = tags.next;
        while (p != &tags) {
            if (tag_indicates_polygon(OSMTYPE_WAY, p->key)) {
                addItem(&poly_tags, p->key, p->value, 1);
                //fprintf(stderr, "found a polygon tag: %s=%s\n", p->key, p->value);
            }
            p = p->next;
        }
    }
    else if( strcmp( type, "boundary" ) == 0 )
    {
        // Boundaries will get converted into multiple geometries:
        // - Linear features will end up in the line and roads tables (useful for admin boundaries)
        // - Polygon features also go into the polygon table (useful for national_forests)
        // The edges of the polygon also get treated as linear fetaures allowing these to be rendered seperately.
        make_boundary = 1;
    }
    else
    {
        /* Unknown type, just exit */
        resetList(&tags);
        resetList(&poly_tags);
        return 0;
    }

    if (pgsql_filter_tags(id, OSMTYPE_WAY, &tags, &polygon) || add_z_order(&tags, &roads)) {
        resetList(&tags);
        resetList(&poly_tags);
        return 0;
    }

    wkt_size = build_geometry(id, xnodes, xcount, make_polygon);

    if (!wkt_size) {
        resetList(&tags);
        resetList(&poly_tags);
        return 0;
    }

    for (i=0;i<wkt_size;i++)
    {
        char *wkt = get_wkt(i);

        if (strlen(wkt)) {
            expire_tiles_from_wkt(wkt, -id);
            /* FIXME: there should be a better way to detect polygons */
            if (!strncmp(wkt, "POLYGON", strlen("POLYGON"))) {
                double area = get_area(i);
                if (area > 0.0) {
                    char tmp[32];
                    snprintf(tmp, sizeof(tmp), "%f", area);
                    addItem(&tags, "way_area", tmp, 0);
                }
                write_wkts(-id, &tags, wkt, t_poly);
                get_interior(i, &interior_lat, &interior_lon);
                //add_parking_node(-id, &tags, interior_lat, interior_lon);
        } else {
                write_wkts(-id, &tags, wkt, t_line);
                if (roads)
                    write_wkts(-id, &tags, wkt, t_roads);
            }
    }
        free(wkt);
    }

    clear_wkts();

    // If we are creating a multipolygon then we
    // mark each member so that we can skip them during iterate_ways
    // but only if the polygon-tags look the same as the outer ring
    if (make_polygon) {
        for (i=0; xcount[i]; i++) {
            int match = 0;
            struct keyval *p = poly_tags.next;
            while (p != &poly_tags) {
                const char *v = getItem(&xtags[i], p->key);
                //fprintf(stderr, "compare polygon tag: %s=%s vs %s\n", p->key, p->value, v ? v : "null");
                if (!v || strcmp(v, p->value)) {
                    match = 0;
                    break;
                }
                match = 1;
                p = p->next;
            }
            if (match) {
                //fprintf(stderr, "match for %d\n", xid[i]);
                Options->mid->ways_done(xid[i]);
                pgsql_delete_way_from_output(xid[i]);
            }
        }
    }

    // If we are making a boundary then also try adding any relations which form complete rings
    // The linear variants will have already been processed above
    if (make_boundary) {
        wkt_size = build_geometry(id, xnodes, xcount, 1);
        for (i=0;i<wkt_size;i++)
        {
            char *wkt = get_wkt(i);

            if (strlen(wkt)) {
                expire_tiles_from_wkt(wkt, -id);
                /* FIXME: there should be a better way to detect polygons */
                if (!strncmp(wkt, "POLYGON", strlen("POLYGON"))) {
                    double area = get_area(i);
                    if (area > 0.0) {
                        char tmp[32];
                        snprintf(tmp, sizeof(tmp), "%f", area);
                        addItem(&tags, "way_area", tmp, 0);
                    }
                    write_wkts(-id, &tags, wkt, t_poly);
                }
            }
            free(wkt);
        }
        clear_wkts();
    }

    resetList(&tags);
    resetList(&poly_tags);
    return 0;
}

static int photo_sort_compare(const void *a, const void *b)
{
	const struct photo_s *ap = a;
	const struct photo_s *bp = b;

	return (ap->type - bp->type) ?: (ap->osmid - bp->osmid);
}

static int pgsql_out_start(const struct output_options *options)
{
    char *sql, tmp[128];
    PGresult   *res;
    int i,j;
    unsigned int sql_len;

    Options = options;

    read_style_file( options->style );

    sql_len = 1024;
    sql = malloc(sql_len);
    assert(sql);

    for (i=0; i<NUM_TABLES; i++) {
        PGconn *sql_conn;

        /* Substitute prefix into name of table */
        {
            char *temp = malloc( strlen(options->prefix) + strlen(tables[i].name) + 1 );
            sprintf( temp, tables[i].name, options->prefix );
            tables[i].name = temp;
        }
        fprintf(stderr, "Setting up table: %s\n", tables[i].name);
        sql_conn = PQconnectdb(options->conninfo);

        /* Check to see that the backend connection was successfully made */
        if (PQstatus(sql_conn) != CONNECTION_OK) {
            fprintf(stderr, "Connection to database failed: %s\n", PQerrorMessage(sql_conn));
            exit_nicely();
        }
        tables[i].sql_conn = sql_conn;

        if (!options->append) {
            sprintf( sql, "DROP TABLE %s;", tables[i].name);
            /* Will be an error if table does not exist and will abort a transaction
             * DROP TABLE IF EXISTS is not present until PostgreSQL-8.2
             */
            res = PQexec(sql_conn, sql);
            PQclear(res);
        }
        else
        {
            sprintf(sql, "SELECT srid FROM geometry_columns WHERE f_table_name='%s';", tables[i].name);
            res = PQexec(sql_conn, sql);
            if (!((PQntuples(res) == 1) && (PQnfields(res) == 1)))
            {
                fprintf(stderr, "Problem reading geometry information for table %s - does it exist?\n", tables[i].name);
                exit_nicely();
            }
            int their_srid = atoi(PQgetvalue(res, 0, 0));
            PQclear(res);
            if (their_srid != SRID)
            {
                fprintf(stderr, "SRID mismatch: cannot append to table %s (SRID %d) using selected SRID %d\n", tables[i].name, their_srid, SRID);
                exit_nicely();
            }
        }

        /* These _tmp tables can be left behind if we run out of disk space */
        sprintf( sql, "DROP TABLE %s_tmp;", tables[i].name);
        res = PQexec(sql_conn, sql);
        PQclear(res);

        pgsql_exec(sql_conn, PGRES_COMMAND_OK, "BEGIN");

        enum OsmType type = (i == t_point)?OSMTYPE_NODE:OSMTYPE_WAY;
        int numTags = exportListCount[type];
        struct taginfo *exportTags = exportList[type];
        if (!options->append) {
            sprintf(sql, "CREATE TABLE %s ( osm_id int4", tables[i].name );
            for (j=0; j < numTags; j++) {
                if( exportTags[j].flags & FLAG_DELETE )
                    continue;
                sprintf(tmp, ",\"%s\" %s", exportTags[j].name, exportTags[j].type);
                if (strlen(sql) + strlen(tmp) + 1 > sql_len) {
                    sql_len *= 2;
                    sql = realloc(sql, sql_len);
                    assert(sql);
                }
                strcat(sql, tmp);
            }
            strcat(sql, " );\n");
            pgsql_exec(sql_conn, PGRES_COMMAND_OK, "%s", sql);
            pgsql_exec(sql_conn, PGRES_TUPLES_OK, "SELECT AddGeometryColumn('%s', 'way', %d, '%s', 2 );\n",
                        tables[i].name, SRID, tables[i].type );
            pgsql_exec(sql_conn, PGRES_COMMAND_OK, "ALTER TABLE %s ALTER COLUMN way SET NOT NULL;\n", tables[i].name);
            /* slim mode needs this to be able to apply diffs */
            if( Options->slim )
                pgsql_exec(sql_conn, PGRES_COMMAND_OK, "CREATE INDEX %s_pkey ON %s USING BTREE (osm_id);\n", tables[i].name, tables[i].name);
        } else {
            /* Add any new columns referenced in the default.style */
            PGresult *res;
            sprintf(sql, "SELECT * FROM %s LIMIT 0;\n", tables[i].name);
            res = PQexec(sql_conn, sql);
            if (PQresultStatus(res) != PGRES_TUPLES_OK) {
                fprintf(stderr, "Error, failed to query table %s\n%s\n", tables[i].name, sql);
                exit_nicely();
            }
            for (j=0; j < numTags; j++) {
                if( exportTags[j].flags & FLAG_DELETE )
                    continue;
                if (PQfnumber(res, exportTags[j].name) < 0) {
#if 0
                    fprintf(stderr, "Append failed. Column \"%s\" is missing from \"%s\"\n", exportTags[j].name, tables[i].name);
                    exit_nicely();
#else
                    fprintf(stderr, "Adding new column \"%s\" to \"%s\"\n", exportTags[j].name, tables[i].name);
                    pgsql_exec(sql_conn, PGRES_COMMAND_OK, "ALTER TABLE %s ADD COLUMN \"%s\" %s;\n", tables[i].name, exportTags[j].name, exportTags[j].type);
#endif
                }
                /* Note: we do not verify the type or delete unused columns */
            }
            PQclear(res);
        }
        pgsql_exec(sql_conn, PGRES_COMMAND_OK, "PREPARE get_way (int4) AS SELECT AsText(way) FROM %s WHERE osm_id = $1;\n", tables[i].name);
        
        /* Generate column list for COPY */
        strcpy(sql, "osm_id");
        for (j=0; j < numTags; j++) {
            if( exportTags[j].flags & FLAG_DELETE )
                continue;
            sprintf(tmp, ",\"%s\"", exportTags[j].name);

            if (strlen(sql) + strlen(tmp) + 1 > sql_len) {
                sql_len *= 2;
                sql = realloc(sql, sql_len);
                assert(sql);
            }
            strcat(sql, tmp);
        }
        tables[i].columns = strdup(sql);
        pgsql_exec(sql_conn, PGRES_COPY_IN, "COPY %s (%s,way) FROM STDIN", tables[i].name, tables[i].columns);

        tables[i].copyMode = 1;
    }
    free(sql);

    qsort(photos, sizeof(photos) / sizeof(*photos), sizeof(*photos),
                    photo_sort_compare);
    for (i = 0; i < (int) (sizeof(photos) / sizeof(*photos)); i ++) {
        photos_num[photos[i].type] ++;
        if (!photo_sorted[photos[i].type])
            photo_sorted[photos[i].type] = photos + i;
    }

    expire_tiles_init(options);

    options->mid->start(options);

    return 0;
}

static void pgsql_pause_copy(struct s_table *table)
{
    PGresult   *res;
    if( !table->copyMode )
        return;
        
    /* Terminate any pending COPY */
    int stop = PQputCopyEnd(table->sql_conn, NULL);
    if (stop != 1) {
       fprintf(stderr, "COPY_END for %s failed: %s\n", table->name, PQerrorMessage(table->sql_conn));
       exit_nicely();
    }

    res = PQgetResult(table->sql_conn);
    if (PQresultStatus(res) != PGRES_COMMAND_OK) {
       fprintf(stderr, "COPY_END for %s failed: %s\n", table->name, PQerrorMessage(table->sql_conn));
       PQclear(res);
       exit_nicely();
    }
    PQclear(res);
    table->copyMode = 0;
}

static void *pgsql_out_stop_one(void *arg)
{
    struct s_table *table = arg;
    PGconn *sql_conn = table->sql_conn;

    if( table->buflen != 0 )
    {
       fprintf( stderr, "Internal error: Buffer for %s has %d bytes after end copy", table->name, table->buflen );
       exit_nicely();
    }

    pgsql_pause_copy(table);
    // Commit transaction
    fprintf(stderr, "Committing transaction for %s\n", table->name);
    pgsql_exec(sql_conn, PGRES_COMMAND_OK, "COMMIT");
    if( !Options->append )
    {
      fprintf(stderr, "Sorting data and creating indexes for %s\n", table->name);
      pgsql_exec(sql_conn, PGRES_COMMAND_OK, "ANALYZE %s;\n", table->name);
      pgsql_exec(sql_conn, PGRES_COMMAND_OK, "CREATE TABLE %s_tmp AS SELECT * FROM %s ORDER BY way;\n", table->name, table->name);
      pgsql_exec(sql_conn, PGRES_COMMAND_OK, "DROP TABLE %s;\n", table->name);
      pgsql_exec(sql_conn, PGRES_COMMAND_OK, "ALTER TABLE %s_tmp RENAME TO %s;\n", table->name, table->name);
      pgsql_exec(sql_conn, PGRES_COMMAND_OK, "CREATE INDEX %s_index ON %s USING GIST (way GIST_GEOMETRY_OPS);\n", table->name, table->name);
      /* slim mode needs this to be able to apply diffs */
      if( Options->slim )
          pgsql_exec(sql_conn, PGRES_COMMAND_OK, "CREATE INDEX %s_pkey ON %s USING BTREE (osm_id);\n", table->name, table->name);
      pgsql_exec(sql_conn, PGRES_COMMAND_OK, "GRANT SELECT ON %s TO PUBLIC;\n", table->name);
      pgsql_exec(sql_conn, PGRES_COMMAND_OK, "ANALYZE %s;\n", table->name);
    }
    PQfinish(sql_conn);
    table->sql_conn = NULL;
    fprintf(stderr, "Completed %s\n", table->name);
    free(table->name);
    free(table->columns);
    return NULL;
}
static void pgsql_out_stop()
{
    int i;
#ifdef HAVE_PTHREAD
    pthread_t threads[NUM_TABLES];
#endif

    /* Processing any remaing to be processed ways */
    Options->mid->iterate_ways( pgsql_out_way );
    Options->mid->iterate_relations( pgsql_process_relation );

#ifdef HAVE_PTHREAD
    for (i=0; i<NUM_TABLES; i++) {
        int ret = pthread_create(&threads[i], NULL, pgsql_out_stop_one, &tables[i]);
        if (ret) {
            fprintf(stderr, "pthread_create() returned an error (%d)", ret);
            exit_nicely();
        }
    }

    /* No longer need to access middle layer -- release memory */
    Options->mid->stop();

    for (i=0; i<NUM_TABLES; i++) {
        int ret = pthread_join(threads[i], NULL);
        if (ret) {
            fprintf(stderr, "pthread_join() returned an error (%d)", ret);
            exit_nicely();
        }
    }
#else
    /* No longer need to access middle layer -- release memory */
    Options->mid->stop();
    for (i=0; i<NUM_TABLES; i++)
        pgsql_out_stop_one(&tables[i]);
#endif

    pgsql_out_cleanup();
    free_style();

    expire_tiles_stop();
}

static int pgsql_add_node(int id, double lat, double lon, struct keyval *tags)
{
  int polygon;
  int filter = pgsql_filter_tags(id, OSMTYPE_NODE, tags, &polygon);
  
  Options->mid->nodes_set(id, lat, lon, tags);
  if( !filter )
      pgsql_out_node(id, tags, lat, lon);
  return 0;
}

static int pgsql_add_way(int id, int *nds, int nd_count, struct keyval *tags)
{
  int polygon = 0;

  // Check whether the way is: (1) Exportable, (2) Maybe a polygon
  int filter = pgsql_filter_tags(id, OSMTYPE_WAY, tags, &polygon);

  // If this isn't a polygon then it can not be part of a multipolygon
  // Hence only polygons are "pending"
  Options->mid->ways_set(id, nds, nd_count, tags, (!filter && polygon) ? 1 : 0);

  if( !polygon && !filter )
  {
    /* Get actual node data and generate output */
    struct osmNode *nodes = malloc( sizeof(struct osmNode) * nd_count );
    int count = Options->mid->nodes_get_list( nodes, nds, nd_count );
    pgsql_out_way(id, tags, nodes, count, 0);
    free(nodes);
  }
  return 0;
}

/* This is the workhorse of pgsql_add_relation, split out because it is used as the callback for iterate relations */
static int pgsql_process_relation(int id, struct member *members, int member_count, struct keyval *tags, int exists)
{
  // (int id, struct keyval *rel_tags, struct osmNode **xnodes, struct keyval **xtags, int *xcount)
  int i, count;
  int *xid = malloc( (member_count+1) * sizeof(int) );
  const char **xrole = malloc( (member_count+1) * sizeof(const char *) );
  int *xcount = malloc( (member_count+1) * sizeof(int) );
  struct keyval *xtags  = malloc( (member_count+1) * sizeof(struct keyval) );
  struct osmNode **xnodes = malloc( (member_count+1) * sizeof(struct osmNode*) );

  /* If the flag says this object may exist already, delete it first */
  if(exists)
      pgsql_delete_relation_from_output(id);

  count = 0;
  for( i=0; i<member_count; i++ )
  {
    /* Need to handle more than just ways... */
    if( members[i].type != OSMTYPE_WAY )
        continue;

    initList(&(xtags[count]));
    if( Options->mid->ways_get( members[i].id, &(xtags[count]), &(xnodes[count]), &(xcount[count]) ) )
      continue;
    xid[count] = members[i].id;
    xrole[count] = members[i].role;
    count++;
  }
  xnodes[count] = NULL;
  xcount[count] = 0;
  xid[count] = 0;
  xrole[count] = NULL;

  // At some point we might want to consider storing the retreived data in the members, rather than as seperate arrays
  pgsql_out_relation(id, tags, xnodes, xtags, xcount, xid, xrole);

  for( i=0; i<count; i++ )
  {
    resetList( &(xtags[i]) );
    free( xnodes[i] );
  }

  free(xid);
  free(xrole);
  free(xcount);
  free(xtags);
  free(xnodes);
  return 0;
}

static int pgsql_add_relation(int id, struct member *members, int member_count, struct keyval *tags)
{
  const char *type = getItem(tags, "type");

  // Must have a type field or we ignore it
  if (!type)
      return 0;

  /* In slim mode we remember these*/
  if(Options->mid->relations_set)
    Options->mid->relations_set(id, members, member_count, tags);
  // (int id, struct keyval *rel_tags, struct osmNode **xnodes, struct keyval **xtags, int *xcount)

  return pgsql_process_relation(id, members, member_count, tags, 0);
}
#define UNUSED  __attribute__ ((unused))

/* Delete is easy, just remove all traces of this object. We don't need to
 * worry about finding objects that depend on it, since the same diff must
 * contain the change for that also. */
static int pgsql_delete_node(int osm_id)
{
    if( !Options->slim )
    {
        fprintf( stderr, "Cannot apply diffs unless in slim mode\n" );
        exit_nicely();
    }
    pgsql_pause_copy(&tables[t_point]);
    expire_tiles_from_db(tables[t_point].sql_conn, osm_id);
    pgsql_exec(tables[t_point].sql_conn, PGRES_COMMAND_OK, "DELETE FROM %s WHERE osm_id = %d", tables[t_point].name, osm_id );
    Options->mid->nodes_delete(osm_id);
    return 0;
}

/* Seperated out because we use it elsewhere */
static int pgsql_delete_way_from_output(int osm_id)
{
    /* Optimisation: we only need this is slim mode */
    if( !Options->slim )
        return 0;
    pgsql_pause_copy(&tables[t_roads]);
    pgsql_pause_copy(&tables[t_line]);
    pgsql_pause_copy(&tables[t_poly]);
    expire_tiles_from_db(tables[t_roads].sql_conn, osm_id);
    expire_tiles_from_db(tables[t_line].sql_conn, osm_id);
    expire_tiles_from_db(tables[t_poly].sql_conn, osm_id);
    pgsql_exec(tables[t_roads].sql_conn, PGRES_COMMAND_OK, "DELETE FROM %s WHERE osm_id = %d", tables[t_roads].name, osm_id );
    pgsql_exec(tables[t_line].sql_conn, PGRES_COMMAND_OK, "DELETE FROM %s WHERE osm_id = %d", tables[t_line].name, osm_id );
    pgsql_exec(tables[t_poly].sql_conn, PGRES_COMMAND_OK, "DELETE FROM %s WHERE osm_id = %d", tables[t_poly].name, osm_id );
    return 0;
}

static int pgsql_delete_way(int osm_id)
{
    if( !Options->slim )
    {
        fprintf( stderr, "Cannot apply diffs unless in slim mode\n" );
        exit_nicely();
    }
    pgsql_delete_way_from_output(osm_id);
    Options->mid->ways_delete(osm_id);
    return 0;
}

/* Relations are identified by using negative IDs */
static int pgsql_delete_relation_from_output(int osm_id)
{
    pgsql_pause_copy(&tables[t_roads]);
    pgsql_pause_copy(&tables[t_line]);
    pgsql_pause_copy(&tables[t_poly]);
    expire_tiles_from_db(tables[t_roads].sql_conn, -osm_id);
    expire_tiles_from_db(tables[t_line].sql_conn, -osm_id);
    expire_tiles_from_db(tables[t_poly].sql_conn, -osm_id);
    pgsql_exec(tables[t_roads].sql_conn, PGRES_COMMAND_OK, "DELETE FROM %s WHERE osm_id = %d", tables[t_roads].name, -osm_id );
    pgsql_exec(tables[t_line].sql_conn, PGRES_COMMAND_OK, "DELETE FROM %s WHERE osm_id = %d", tables[t_line].name, -osm_id );
    pgsql_exec(tables[t_poly].sql_conn, PGRES_COMMAND_OK, "DELETE FROM %s WHERE osm_id = %d", tables[t_poly].name, -osm_id );
    return 0;
}

static int pgsql_delete_relation(int osm_id)
{
    if( !Options->slim )
    {
        fprintf( stderr, "Cannot apply diffs unless in slim mode\n" );
        exit_nicely();
    }
    pgsql_delete_relation_from_output(osm_id);
    Options->mid->relations_delete(osm_id);
    return 0;
}

/* Modify is slightly trickier. The basic idea is we simply delete the
 * object and create it with the new parameters. Then we need to mark the
 * objects that depend on this one */
static int pgsql_modify_node(int osm_id, double lat, double lon, struct keyval *tags)
{
    if( !Options->slim )
    {
        fprintf( stderr, "Cannot apply diffs unless in slim mode\n" );
        exit_nicely();
    }
    pgsql_delete_node(osm_id);
    pgsql_add_node(osm_id, lat, lon, tags);
    Options->mid->node_changed(osm_id);
    return 0;
}

static int pgsql_modify_way(int osm_id, int *nodes, int node_count, struct keyval *tags)
{
    if( !Options->slim )
    {
        fprintf( stderr, "Cannot apply diffs unless in slim mode\n" );
        exit_nicely();
    }
    pgsql_delete_way(osm_id);
    pgsql_add_way(osm_id, nodes, node_count, tags);
    Options->mid->way_changed(osm_id);
    return 0;
}

static int pgsql_modify_relation(int osm_id, struct member *members, int member_count, struct keyval *tags)
{
    if( !Options->slim )
    {
        fprintf( stderr, "Cannot apply diffs unless in slim mode\n" );
        exit_nicely();
    }
    pgsql_delete_relation(osm_id);
    pgsql_add_relation(osm_id, members, member_count, tags);
    Options->mid->relation_changed(osm_id);
    return 0;
}

struct output_t out_pgsql = {
        start:     pgsql_out_start,
        stop:      pgsql_out_stop,
        cleanup:   pgsql_out_cleanup,
        node_add:      pgsql_add_node,
        way_add:       pgsql_add_way,
        relation_add:  pgsql_add_relation,
        
        node_modify: pgsql_modify_node,
        way_modify: pgsql_modify_way,
        relation_modify: pgsql_modify_relation,

        node_delete: pgsql_delete_node,
        way_delete: pgsql_delete_way,
        relation_delete: pgsql_delete_relation
};