/**
- * Collects search constraints that are independent of the
+ * Collection of search constraints that are independent of the
* actual interpretation of the search query.
*
* The search context is shared between all SearchDescriptions. This
*/
class SearchContext
{
+ /// Search radius around a given Near reference point.
private $fNearRadius = false;
+ /// True if search must be restricted to viewbox only.
+ public $bViewboxBounded = false;
- // cached SQL
-
+ /// Reference point for search (as SQL).
public $sqlNear = '';
+ /// Viewbox selected for search (as SQL).
+ public $sqlViewboxSmall = '';
+ /// Viewbox with a larger buffer around (as SQL).
+ public $sqlViewboxLarge = '';
+ /// Reference along a route (as SQL).
+ public $sqlViewboxCentre = '';
+ /// List of countries to restrict search to (as SQL).
+ public $sqlCountryList = '';
+ /// List of place IDs to exclude (as SQL).
+ private $sqlExcludeList = '';
+
+ /**
+ * Check if a reference point is defined.
+ *
+ * @return bool True if a reference point is defined.
+ */
public function hasNearPoint()
{
return $this->fNearRadius !== false;
}
+ /**
+ * Get radius around reference point.
+ *
+ * @return float Search radius around reference point.
+ */
public function nearRadius()
{
return $this->fNearRadius;
}
+ /**
+ * Set search reference point in WGS84.
+ *
+ * If set, then only places around this point will be taken into account.
+ *
+ * @param float $fLat Latitude of point.
+ * @param float $fLon Longitude of point.
+ * @param float $fRadius Search radius around point.
+ *
+ * @return void
+ */
public function setNearPoint($fLat, $fLon, $fRadius = 0.1)
{
$this->fNearRadius = $fRadius;
}
/**
- * Extract a coordinate point from a query string.
+ * Check if the search is geographically restricted.
+ *
+ * Searches are restricted if a reference point is given or if
+ * a bounded viewbox is set.
+ *
+ * @return bool True, if the search is geographically bounded.
+ */
+ public function isBoundedSearch()
+ {
+ return $this->hasNearPoint() || ($this->sqlViewboxSmall && $this->bViewboxBounded);
+ }
+
+ /**
+ * Set rectangular viewbox.
+ *
+ * The viewbox may be bounded which means that no search results
+ * must be outside the viewbox.
+ *
+ * @param float[4] $aViewBox Coordinates of the viewbox.
+ * @param bool $bBounded True if the viewbox is bounded.
+ *
+ * @return void
+ */
+ public function setViewboxFromBox(&$aViewBox, $bBounded)
+ {
+ $this->bViewboxBounded = $bBounded;
+ $this->sqlViewboxCentre = '';
+
+ $this->sqlViewboxSmall = sprintf(
+ 'ST_SetSRID(ST_MakeBox2D(ST_Point(%F,%F),ST_Point(%F,%F)),4326)',
+ $aViewBox[0],
+ $aViewBox[1],
+ $aViewBox[2],
+ $aViewBox[3]
+ );
+
+ $fHeight = abs($aViewBox[0] - $aViewBox[2]);
+ $fWidth = abs($aViewBox[1] - $aViewBox[3]);
+
+ $this->sqlViewboxLarge = sprintf(
+ 'ST_SetSRID(ST_MakeBox2D(ST_Point(%F,%F),ST_Point(%F,%F)),4326)',
+ max($aViewBox[0], $aViewBox[2]) + $fHeight,
+ max($aViewBox[1], $aViewBox[3]) + $fWidth,
+ min($aViewBox[0], $aViewBox[2]) - $fHeight,
+ min($aViewBox[1], $aViewBox[3]) - $fWidth
+ );
+ }
+
+ /**
+ * Set viewbox along a route.
+ *
+ * The viewbox may be bounded which means that no search results
+ * must be outside the viewbox.
+ *
+ * @param object $oDB Nominatim::DB instance to use for computing the box.
+ * @param string[] $aRoutePoints List of x,y coordinates along a route.
+ * @param float $fRouteWidth Buffer around the route to use.
+ * @param bool $bBounded True if the viewbox bounded.
+ *
+ * @return void
+ */
+ public function setViewboxFromRoute(&$oDB, $aRoutePoints, $fRouteWidth, $bBounded)
+ {
+ $this->bViewboxBounded = $bBounded;
+ $this->sqlViewboxCentre = "ST_SetSRID('LINESTRING(";
+ $sSep = '';
+ foreach ($aRoutePoints as $aPoint) {
+ $fPoint = (float)$aPoint;
+ $this->sqlViewboxCentre .= $sSep.$fPoint;
+ $sSep = ($sSep == ' ') ? ',' : ' ';
+ }
+ $this->sqlViewboxCentre .= ")'::geometry,4326)";
+
+ $sSQL = 'ST_BUFFER('.$this->sqlViewboxCentre.','.($fRouteWidth/69).')';
+ $sGeom = $oDB->getOne('select '.$sSQL, null, 'Could not get small viewbox');
+ $this->sqlViewboxSmall = "'".$sGeom."'::geometry";
+
+ $sSQL = 'ST_BUFFER('.$this->sqlViewboxCentre.','.($fRouteWidth/30).')';
+ $sGeom = $oDB->getOne('select '.$sSQL, null, 'Could not get large viewbox');
+ $this->sqlViewboxLarge = "'".$sGeom."'::geometry";
+ }
+
+ /**
+ * Set list of excluded place IDs.
+ *
+ * @param integer[] $aExcluded List of IDs.
+ *
+ * @return void
+ */
+ public function setExcludeList($aExcluded)
+ {
+ $this->sqlExcludeList = ' not in ('.join(',', $aExcluded).')';
+ }
+
+ /**
+ * Set list of countries to restrict search to.
+ *
+ * @param string[] $aCountries List of two-letter lower-case country codes.
+ *
+ * @return void
+ */
+ public function setCountryList($aCountries)
+ {
+ $this->sqlCountryList = '('.join(',', array_map('addQuotes', $aCountries)).')';
+ }
+
+ /**
+ * Extract a reference point from a query string.
*
* @param string $sQuery Query to scan.
*
- * @return The remaining query string.
+ * @return string The remaining query string.
*/
public function setNearPointFromQuery($sQuery)
{
return $sQuery;
}
+ /**
+ * Get an SQL snippet for computing the distance from the reference point.
+ *
+ * @param string $sObj SQL variable name to compute the distance from.
+ *
+ * @return string An SQL string.
+ */
public function distanceSQL($sObj)
{
return 'ST_Distance('.$this->sqlNear.", $sObj)";
}
+ /**
+ * Get an SQL snippet for checking if something is within range of the
+ * reference point.
+ *
+ * @param string $sObj SQL variable name to compute if it is within range.
+ *
+ * @return string An SQL string.
+ */
public function withinSQL($sObj)
{
return sprintf('ST_DWithin(%s, %s, %F)', $sObj, $this->sqlNear, $this->fNearRadius);
}
+
+ /**
+ * Get an SQL snippet of the importance factor of the viewbox.
+ *
+ * The importance factor is computed by checking if an object is within
+ * the viewbox and/or the extended version of the viewbox.
+ *
+ * @param string $sObj SQL variable name of object to weight the importance
+ *
+ * @return string SQL snippet of the factor with a leading multiply sign.
+ */
+ public function viewboxImportanceSQL($sObj)
+ {
+ $sSQL = '';
+
+ if ($this->sqlViewboxSmall) {
+ $sSQL = " * CASE WHEN ST_Contains($this->sqlViewboxSmall, $sObj) THEN 1 ELSE 0.5 END";
+ }
+ if ($this->sqlViewboxLarge) {
+ $sSQL = " * CASE WHEN ST_Contains($this->sqlViewboxLarge, $sObj) THEN 1 ELSE 0.5 END";
+ }
+
+ return $sSQL;
+ }
+
+ /**
+ * SQL snippet checking if a place ID should be excluded.
+ *
+ * @param string $sVariable SQL variable name of place ID to check,
+ * potentially prefixed with more SQL.
+ *
+ * @return string SQL snippet.
+ */
+ public function excludeSQL($sVariable)
+ {
+ if ($this->sqlExcludeList) {
+ return $sVariable.$this->sqlExcludeList;
+ }
+
+ return '';
+ }
+
+ public function debugInfo()
+ {
+ return array(
+ 'Near radius' => $this->fNearRadius,
+ 'Near point (SQL)' => $this->sqlNear,
+ 'Bounded viewbox' => $this->bViewboxBounded,
+ 'Viewbox (SQL, small)' => $this->sqlViewboxSmall,
+ 'Viewbox (SQL, large)' => $this->sqlViewboxLarge,
+ 'Viewbox (SQL, centre)' => $this->sqlViewboxCentre,
+ 'Countries (SQL)' => $this->sqlCountryList,
+ 'Excluded IDs (SQL)' => $this->sqlExcludeList
+ );
+ }
}
projects / nominatim.git / blobdiff