/**
* Convert a raw coverage value to WKT.
*
* @param string $coverage The raw coverage.
* @return string|null The WKT.
*/
function nl_extractWkt($coverage)
{
$wkt = null;
// Get coverage format.
$format = geoPHP::detectFormat($coverage);
// Convert / reduce to WKT.
if (in_array($format, array('wkt', 'kml'))) {
$wkt = geoPHP::load($coverage)->out('wkt');
}
return $wkt;
}
/**
* Return record coverage data from the NeatlineFeatures plugin.
*
* @param $record NeatlineRecord The record to get the feature for.
* @return string|null
*/
function nl_getNeatlineFeaturesWkt($record)
{
// Halt if Features is not present.
if (!plugin_is_active('NeatlineFeatures')) {
return;
}
$db = get_db();
// Get raw coverage.
$result = $db->fetchOne("SELECT geo FROM `{$db->prefix}neatline_features`\n WHERE is_map=1 AND item_id=?;", $record->item_id);
if ($result) {
// If KML, convert to WKT.
if (geoPHP::detectFormat($result) == 'kml') {
$result = nl_kml2wkt(trim($result));
} else {
$result = 'GEOMETRYCOLLECTION(' . implode(',', explode('|', $result)) . ')';
}
}
return $result;
}
static function detectFormat(&$input)
{
$mem = fopen('php://memory', 'r+');
fwrite($mem, $input, 11);
// Write 11 bytes - we can detect the vast majority of formats in the first 11 bytes
fseek($mem, 0);
$bytes = unpack("c*", fread($mem, 11));
// If bytes is empty, then we were passed empty input
if (empty($bytes)) {
return FALSE;
}
// First char is a tab, space or carriage-return. trim it and try again
if ($bytes[1] == 9 || $bytes[1] == 10 || $bytes[1] == 32) {
return geoPHP::detectFormat(ltrim($input));
}
// Detect WKB or EWKB -- first byte is 1 (little endian indicator)
if ($bytes[1] == 1) {
// If SRID byte is TRUE (1), it's EWKB
if ($bytes[5]) {
return 'ewkb';
} else {
return 'wkb';
}
}
// Detect HEX encoded WKB or EWKB (PostGIS format) -- first byte is 48, second byte is 49 (hex '01' => first-byte = 1)
if ($bytes[1] == 48 && $bytes[2] == 49) {
// The shortest possible WKB string (LINESTRING EMPTY) is 18 hex-chars (9 encoded bytes) long
// This differentiates it from a geohash, which is always shorter than 18 characters.
if (strlen($input) >= 18) {
//@@TODO: Differentiate between EWKB and WKB -- check hex-char 10 or 11 (SRID bool indicator at encoded byte 5)
return 'ewkb:1';
}
}
// Detect GeoJSON - first char starts with {
if ($bytes[1] == 123) {
return 'json';
}
// Detect EWKT - first char is S
if ($bytes[1] == 83) {
return 'ewkt';
}
// Detect WKT - first char starts with P (80), L (76), M (77), or G (71)
$wkt_chars = array(80, 76, 77, 71);
if (in_array($bytes[1], $wkt_chars)) {
return 'wkt';
}
// Detect XML -- first char is <
if ($bytes[1] == 60) {
// grab the first 256 characters
$string = substr($input, 0, 256);
if (strpos($string, '<kml') !== FALSE) {
return 'kml';
}
if (strpos($string, '<coordinate') !== FALSE) {
return 'kml';
}
if (strpos($string, '<gpx') !== FALSE) {
return 'gpx';
}
if (strpos($string, '<georss') !== FALSE) {
return 'georss';
}
if (strpos($string, '<rss') !== FALSE) {
return 'georss';
}
if (strpos($string, '<feed') !== FALSE) {
return 'georss';
}
}
// We need an 8 byte string for geohash and unpacked WKB / WKT
fseek($mem, 0);
$string = trim(fread($mem, 8));
// Detect geohash - geohash ONLY contains lowercase chars and numerics
preg_match('/[a-z0-9]+/', $string, $matches);
if ($matches[0] == $string) {
return 'geohash';
}
// What do you get when you cross an elephant with a rhino?
// http://youtu.be/RCBn5J83Poc
return FALSE;
}
function test_detection($value, $format, $file)
{
$detected = geoPHP::detectFormat($value);
if ($detected != $format) {
if ($detected) {
print 'detected as ' . $detected . "\n";
} else {
print "format not detected\n";
}
}
// Make sure it loads using auto-detect
geoPHP::load($value);
}
