/*
* Set a given bbox matching a feature collection's outerboundaries
* or a simple feature's outerboundaries
* Bbox is set from a list containing one or several layer names
* and optionnaly one or several WHERE SQL statement following each layer name
*/
ows_bbox *ows_bbox_boundaries(ows * o, list * from, list * where, ows_srs * srs)
{
ows_bbox *bb;
buffer *sql;
list *geom;
list_node *ln_from, *ln_where, *ln_geom;
PGresult *res;
assert(o && from && where && srs);
bb = ows_bbox_init();
if (from->size != where->size) return bb;
sql = buffer_init();
/* Put into a buffer the SQL request calculating an extent */
buffer_add_str(sql, "SELECT ST_xmin(g.extent), ST_ymin(g.extent), ST_xmax(g.extent), ST_ymax(g.extent) FROM ");
buffer_add_str(sql, "(SELECT ST_Extent(foo.the_geom) as extent FROM ( ");
/* For each layer name or each geometry column, make an union between retrieved features */
for (ln_from = from->first, ln_where = where->first;
ln_from;
ln_from = ln_from->next, ln_where = ln_where->next) {
geom = ows_psql_geometry_column(o, ln_from->value);
for (ln_geom = geom->first ; ln_geom ; ln_geom = ln_geom->next) {
buffer_add_str(sql, " (SELECT ST_Transform(\"");
buffer_copy(sql, ln_geom->value);
buffer_add_str(sql, "\"::geometry, ");
buffer_add_int(sql, srs->srid);
buffer_add_str(sql, ") AS \"the_geom\" FROM \"");
buffer_copy(sql, ows_psql_schema_name(o, ln_from->value));
buffer_add_str(sql, "\".\"");
buffer_copy(sql, ows_psql_table_name(o, ln_from->value));
buffer_add_str(sql, "\" ");
buffer_copy(sql, ln_where->value);
buffer_add_str(sql, ")");
if (ln_geom->next) buffer_add_str(sql, " UNION ALL ");
}
if (ln_from->next) buffer_add_str(sql, " UNION ALL ");
}
buffer_add_str(sql, " ) AS foo) AS g");
res = ows_psql_exec(o, sql->buf);
buffer_free(sql);
if (PQresultStatus(res) != PGRES_TUPLES_OK || PQntuples(res) != 4) {
PQclear(res);
return bb;
}
bb->xmin = strtod(PQgetvalue(res, 0, 0), NULL);
bb->ymin = strtod(PQgetvalue(res, 0, 1), NULL);
bb->xmax = strtod(PQgetvalue(res, 0, 2), NULL);
bb->ymax = strtod(PQgetvalue(res, 0, 3), NULL);
/* FIXME Error handling */
ows_srs_copy(bb->srs, srs);
PQclear(res);
return bb;
}
/*
* Set a geobbox matching a layer's extent
*/
ows_geobbox *ows_geobbox_compute(ows * o, buffer * layer_name)
{
double xmin, ymin, xmax, ymax;
buffer *sql;
PGresult *res;
ows_geobbox *g;
ows_bbox *bb;
list *geom;
list_node *ln;
bool first = true;
assert(o);
assert(layer_name);
sql = buffer_init();
geom = ows_psql_geometry_column(o, layer_name);
assert(geom);
g = ows_geobbox_init();
xmin = ymin = xmax = ymax = 0.0;
for (ln = geom->first; ln ; ln = ln->next)
{
buffer_add_str(sql, "SELECT ST_xmin(g), ST_ymin(g), ST_xmax(g), ST_ymax(g) FROM ");
if (o->estimated_extent)
{
buffer_add_str(sql, "(SELECT ST_Transform(ST_SetSRID(ST_Estimated_Extent('");
buffer_copy(sql, ows_psql_schema_name(o, layer_name));
buffer_add_str(sql, "','");
buffer_copy(sql, ows_psql_table_name(o, layer_name));
buffer_add_str(sql, "','");
buffer_copy(sql, ln->value);
buffer_add_str(sql, "'), (SELECT ST_SRID(\"");
buffer_copy(sql, ln->value);
buffer_add_str(sql, "\") FROM ");
buffer_copy(sql, ows_psql_schema_name(o, layer_name));
buffer_add_str(sql, ".\"");
buffer_copy(sql, ows_psql_table_name(o, layer_name));
buffer_add_str(sql, "\" LIMIT 1)) ,4326) AS g) AS foo");
} else {
buffer_add_str(sql, "(SELECT ST_Transform(ST_SetSRID(ST_Extent(\"");
buffer_copy(sql, ln->value);
buffer_add_str(sql, "\"), (SELECT ST_SRID(\"");
buffer_copy(sql, ln->value);
buffer_add_str(sql, "\") FROM ");
buffer_copy(sql, ows_psql_schema_name(o, layer_name));
buffer_add_str(sql, ".\"");
buffer_copy(sql, ows_psql_table_name(o, layer_name));
buffer_add_str(sql, "\" LIMIT 1)), 4326) AS g ");
buffer_add_str(sql, " FROM ");
buffer_copy(sql, ows_psql_schema_name(o, layer_name));
buffer_add_str(sql, ".\"");
buffer_copy(sql, ows_psql_table_name(o, layer_name));
buffer_add_str(sql, "\" ) AS foo");
}
res = ows_psql_exec(o, sql->buf);
buffer_empty(sql);
if (PQresultStatus(res) != PGRES_TUPLES_OK) {
PQclear(res);
buffer_free(sql);
return g;
}
if (first || atof(PQgetvalue(res, 0, 0)) < xmin) xmin = atof(PQgetvalue(res, 0, 0));
if (first || atof(PQgetvalue(res, 0, 1)) < ymin) ymin = atof(PQgetvalue(res, 0, 1));
if (first || atof(PQgetvalue(res, 0, 2)) > xmax) xmax = atof(PQgetvalue(res, 0, 2));
if (first || atof(PQgetvalue(res, 0, 3)) > ymax) ymax = atof(PQgetvalue(res, 0, 3));
first = false;
PQclear(res);
}
buffer_free(sql);
bb = ows_bbox_init();
ows_bbox_set(o, bb, xmin, ymin, xmax, ymax, 4326);
ows_geobbox_set_from_bbox(o, g, bb);
ows_bbox_free(bb);
return g;
}
