| 1 |
<?php
|
| 2 |
|
| 3 |
|
| 4 |
function letters_location_nearby_postalcodes_bylocation($location, $distance, $distance_unit = 'km') {
|
| 5 |
// DEBUG: commented code is for testing/debugging purposes
|
| 6 |
//$start_time = microtime();
|
| 7 |
|
| 8 |
$latlon = location_latlon_rough($location);
|
| 9 |
|
| 10 |
// If we could not get lat/lon coordinates for the given location, return an empty search result set.
|
| 11 |
if (!isset($latlon['lat']) || !isset($latlon['lon'])) {
|
| 12 |
return array();
|
| 13 |
}
|
| 14 |
|
| 15 |
// If the distance parameters did not make sense, return an empty search result set.
|
| 16 |
if (!($distance_float = _location_convert_distance_to_meters($distance, $distance_unit))) {
|
| 17 |
return array();
|
| 18 |
}
|
| 19 |
|
| 20 |
$search_results = _letters_location_nearby_postalcodes($latlon['lon'], $latlon['lat'], $distance_float);
|
| 21 |
|
| 22 |
//DEBUG: commented code is for testing/debugging
|
| 23 |
//$format_start_time = microtime();
|
| 24 |
|
| 25 |
_letters_location_format_search_result_distances($search_results, $distance_unit);
|
| 26 |
|
| 27 |
//$format_end_time = microtime();
|
| 28 |
//print 'Time for FORMATTING to complete: '. _letters_location_time_difference($format_end_time, $format_start_time) ."<br/>\n";
|
| 29 |
|
| 30 |
// DEBUG: commented code is for testing/debugging purposes
|
| 31 |
//$end_time = microtime();
|
| 32 |
//print 'Time for this search to complete: '. _letters_location_time_difference($end_time, $start_time) ."<br/>\n";
|
| 33 |
|
| 34 |
return $search_results;
|
| 35 |
}
|
| 36 |
|
| 37 |
|
| 38 |
function _letters_location_nearby_postalcodes($lon, $lat, $distance) {
|
| 39 |
# $search_results = _letters_location_search_results_from_cache($lon, $lat, $distance);
|
| 40 |
|
| 41 |
// If there were usable cached search_results then return those and go no further... awwwww yeah.
|
| 42 |
# if (count($search_results)) {
|
| 43 |
# return $search_results;
|
| 44 |
# }
|
| 45 |
//------------------------------------------------------------------------------------------
|
| 46 |
// Pulling from the cache takes place right here.
|
| 47 |
// The cache id ("cid", to be inserted into the cache table) will be a concatenation of
|
| 48 |
// -> "letters_location_prox_search:".
|
| 49 |
// -> round($lon, 3) . ':'.
|
| 50 |
// -> round($lat, 3) . ":".
|
| 51 |
// -> $distance
|
| 52 |
// The value of the cached item will be a serialize($result_array)
|
| 53 |
//
|
| 54 |
// The cache will be cleared of proximity searches when there is a change in countries that have
|
| 55 |
// been configured into the system.
|
| 56 |
//------------------------------------------------------------------------------------------
|
| 57 |
|
| 58 |
$search_results = array();
|
| 59 |
|
| 60 |
$latrange = earth_latitude_range($lon, $lat, $distance);
|
| 61 |
$lonrange = earth_longitude_range($lon, $lat, $distance);
|
| 62 |
|
| 63 |
//$query_start_time = microtime();
|
| 64 |
|
| 65 |
$result = db_query('SELECT zip, city, state, country, '. earth_distance_sql($lon, $lat) .' as distance FROM {zipcodes} WHERE latitude > %f AND latitude < %f AND longitude > %f AND longitude < %f AND '. earth_distance_sql($lon, $lat) .' < %f ORDER by distance', $latrange[0], $latrange[1], $lonrange[0], $lonrange[1], $distance);
|
| 66 |
|
| 67 |
while ($result_row = db_fetch_object($result)) {
|
| 68 |
$search_results[$result_row->country . $result_row->zip] = array('city' => $result_row->city, 'province' => $result_row->state, 'distance' => $result_row->distance);
|
| 69 |
}
|
| 70 |
|
| 71 |
//DEBUG: commented code for testing/debugging purposes
|
| 72 |
//$query_end_time = microtime();
|
| 73 |
|
| 74 |
//print 'TOTAL TIME FOR _letters_location_nearby_postalcodes() '. _letters_location_time_difference($query_end_time, $query_start_time) ."<br/>\n";
|
| 75 |
//--------------------------------------------------------------------------------------------
|
| 76 |
// This is the spot where search results are cached
|
| 77 |
|
| 78 |
#cache_set('letters_location_prox_search:'. round($lon, 3) .':'. round($lat, 3) .':'. $distance, 'cache', serialize($search_results));
|
| 79 |
|
| 80 |
// DEBUG: commented code is for testing/debugging purposes
|
| 81 |
//print 'POSTAL CODE SEARCH CACHING: Wrote new search results to cache'."<br/>\n";
|
| 82 |
//--------------------------------------------------------------------------------------------
|
| 83 |
return $search_results;
|
| 84 |
}
|
| 85 |
|
| 86 |
|
| 87 |
|
| 88 |
function _letters_location_search_results_from_cache($lon, $lat, $distance) {
|
| 89 |
$cache_id_prefix = 'letters_location_prox_search:'. round($lon, 3) .':'. round($lat, 3) .':';
|
| 90 |
|
| 91 |
$result = db_query("SELECT cid FROM {cache} WHERE cid LIKE '%s%%'", $cache_id_prefix);
|
| 92 |
|
| 93 |
if ($result_row = db_fetch_object($result)) {
|
| 94 |
// A previous search has been done on the same search point, possibily with the an equal or different
|
| 95 |
// search radius.
|
| 96 |
$cached_key_fields = explode(':', $result_row->cid);
|
| 97 |
$previous_search_radius = $cached_key_fields[3];
|
| 98 |
|
| 99 |
// If the search-radius is less than or equal to the previous search-radius, then just use
|
| 100 |
// the appropriate subset of the previous search result.
|
| 101 |
// This is very convenient since previous search results are sorted in ascending order
|
| 102 |
// by their distance from the search point.
|
| 103 |
if ($distance <= $previous_search_radius) {
|
| 104 |
|
| 105 |
$cached_search_results = cache_get($result_row->cid);
|
| 106 |
$cached_search_results = unserialize($cached_search_results->data);
|
| 107 |
// If the cached-search had the exact same search-radius, just return the entire search result's
|
| 108 |
// array from before,
|
| 109 |
// otherwise, go through the distance-sorted search results and pick them out until the distances
|
| 110 |
// of each search result start being something greater than the current search-radius
|
| 111 |
if ($distance == $previous_search_radius) {
|
| 112 |
// DEBUG: commented code is for testing/debugging purposes
|
| 113 |
//print 'POSTAL CODE SEARCH CACHING: Returning EXACT SAME of search results from before'."<br/>\n";
|
| 114 |
return $cached_search_results;
|
| 115 |
}
|
| 116 |
else {
|
| 117 |
$current_search_results = array();
|
| 118 |
foreach ($cached_search_results as $key => $cached_result) {
|
| 119 |
if ($cached_result['distance'] <= $distance) {
|
| 120 |
$current_search_results[$key] = $cached_result;
|
| 121 |
}
|
| 122 |
else {
|
| 123 |
break;
|
| 124 |
}
|
| 125 |
}
|
| 126 |
// DEBUG: commented code is for testing/debugging purposes
|
| 127 |
//print 'POSTAL CODE SEARCH CACHING: Returning SUBSET of a previous search\'s results'."<br/>\n";
|
| 128 |
return $current_search_results;
|
| 129 |
}
|
| 130 |
}
|
| 131 |
else {
|
| 132 |
// If the previous search-radius on the same point is smaller than the current search-radius,
|
| 133 |
// then delete the previous search from the cache to make way in the cache for the results of
|
| 134 |
// the current, more comprehensive search being done on the same point, but on a larger radius.
|
| 135 |
// Return an empty array to let the calling function know that it will have to do a new search.
|
| 136 |
|
| 137 |
// DEBUG: commented code is for testing/debugging purposes
|
| 138 |
//print 'POSTAL CODE SEARCH CACHING: Throwing out old search on a point because new search uses larger search-radius'."<br/>\n";
|
| 139 |
cache_clear_all($result_row->cid, 'cache');
|
| 140 |
return array();
|
| 141 |
}
|
| 142 |
|
| 143 |
}
|
| 144 |
else {
|
| 145 |
// This else-clause ties back to the first if-clause in this function.
|
| 146 |
// It executes if no search has been done on this point.
|
| 147 |
// If the {cache} table did not contain any useful cache id's, return the empty array.
|
| 148 |
// This will let the calling function know that it has to do an original search.
|
| 149 |
return array();
|
| 150 |
}
|
| 151 |
}
|
| 152 |
|
| 153 |
|
| 154 |
function _letters_location_format_search_result_distances(&$results_array, $distance_unit = 'km') {
|
| 155 |
if ($distance_unit != 'km' && $distance_unit != 'mile') {
|
| 156 |
$distance_unit = 'km';
|
| 157 |
}
|
| 158 |
|
| 159 |
// $conversion_factor = number to divide by to convert meters to $distance_unit
|
| 160 |
// At this point, $distance_unit == 'km' or 'mile' and nothing else
|
| 161 |
$conversion_factor = ($distance_unit == 'km') ? 1000.0 : 1609.347;
|
| 162 |
|
| 163 |
foreach ($results_array as $index => $single_result) {
|
| 164 |
$results_array[$index]['distance'] = round($single_result['distance']/$conversion_factor, 1);
|
| 165 |
}
|
| 166 |
}
|
| 167 |
|
Parent Directory
| 
Revision Log
| 
Revision Graph