/**
* Get paginated row data
*
* Returns the Nth "page" of objects, assuming Y objects per page.
* Defaults to assuming the first page, with 50 objects per page, is
* desired.
*
* @param integer $num The page number to retrieve
* @param integer $count The number of rows to retrieve
* @param string $sorts How the results should be sorted
* @return array
*/
public static function page($num = 1, $count = 50, $sorts = 'pkeys')
{
$class = get_called_class();
$table = static::table_for_class($class);
$cols = static::column_names($class);
$pkeys = static::primary_keys($class);
$order = array();
if ($sorts == 'pkeys') {
$name = "_page_{$table}_pkeys";
foreach ($pkeys as $pkey) {
array_push($order, "{$pkey} ASC");
}
} else {
$idx = array();
foreach ($sorts as $sort) {
if (preg_match('/^(.*)\\s*(ASC|DESC)$/i', $sort, $matches)) {
$sort = $matches[1];
$order = strtoupper($matches[2]);
} else {
$order = 'ASC';
}
$index = array_search($sort, $cols);
if ($index === false) {
$msg = "{$sort} is not a valid column for sorting";
throw new BadColumnException($table, $sort, $msg);
}
$sort = Database::quote_identifier($sort);
array_push($idx, $index . ($order == 'ASC' ? '+' : '-'));
array_push($order, "{$sort} {$order}");
}
$name = "_page_{$table}_" . join($idx, ',');
}
$cols = array_values(Database::quote_identifiers($cols));
$table = Database::quote_identifier($table);
if (Database::prepared($name)) {
$query = '';
} else {
$cols = join(', ', $cols);
$ords = join(', ', $order);
$query = "SELECT {$cols} FROM {$table} ORDER BY {$ords} " . 'LIMIT $1 OFFSET $2';
}
$offset = ($num - 1) * $count;
$return = array();
$result = Database::prefetch($query, array($count, $offset), $name);
foreach ($result as $row) {
$obj = new $class();
$obj->_set_all($row);
array_push($return, $obj);
}
return $return;
}
