home/alospiesjs/www/apis/youtube/vendor/ramsey/uuid/src/Generator/CombGenerator.php000060400000006547151163565140024663 0ustar00 * @license http://opensource.org/licenses/MIT MIT */ declare(strict_types=1); namespace Ramsey\Uuid\Generator; use Ramsey\Uuid\Converter\NumberConverterInterface; use Ramsey\Uuid\Exception\InvalidArgumentException; use function bin2hex; use function explode; use function hex2bin; use function microtime; use function str_pad; use function substr; use const STR_PAD_LEFT; /** * CombGenerator generates COMBs (combined UUID/timestamp) * * The CombGenerator, when used with the StringCodec (and, by proxy, the * TimestampLastCombCodec) or the TimestampFirstCombCodec, combines the current * timestamp with a UUID (hence the name "COMB"). The timestamp either appears * as the first or last 48 bits of the COMB, depending on the codec used. * * By default, COMBs will have the timestamp set as the last 48 bits of the * identifier. * * ``` php * $factory = new UuidFactory(); * * $factory->setRandomGenerator(new CombGenerator( * $factory->getRandomGenerator(), * $factory->getNumberConverter() * )); * * $comb = $factory->uuid4(); * ``` * * To generate a COMB with the timestamp as the first 48 bits, set the * TimestampFirstCombCodec as the codec. * * ``` php * $factory->setCodec(new TimestampFirstCombCodec($factory->getUuidBuilder())); * ``` * * @link https://www.informit.com/articles/printerfriendly/25862 The Cost of GUIDs as Primary Keys */ class CombGenerator implements RandomGeneratorInterface { public const TIMESTAMP_BYTES = 6; /** * @var RandomGeneratorInterface */ private $randomGenerator; /** * @var NumberConverterInterface */ private $converter; public function __construct( RandomGeneratorInterface $generator, NumberConverterInterface $numberConverter ) { $this->converter = $numberConverter; $this->randomGenerator = $generator; } /** * @throws InvalidArgumentException if $length is not a positive integer * greater than or equal to CombGenerator::TIMESTAMP_BYTES * * @inheritDoc */ public function generate(int $length): string { if ($length < self::TIMESTAMP_BYTES) { throw new InvalidArgumentException( 'Length must be a positive integer greater than or equal to ' . self::TIMESTAMP_BYTES ); } $hash = ''; if (self::TIMESTAMP_BYTES > 0 && $length > self::TIMESTAMP_BYTES) { $hash = $this->randomGenerator->generate($length - self::TIMESTAMP_BYTES); } $lsbTime = str_pad( $this->converter->toHex($this->timestamp()), self::TIMESTAMP_BYTES * 2, '0', STR_PAD_LEFT ); return (string) hex2bin( str_pad( bin2hex($hash), $length - self::TIMESTAMP_BYTES, '0' ) . $lsbTime ); } /** * Returns current timestamp a string integer, precise to 0.00001 seconds */ private function timestamp(): string { $time = explode(' ', microtime(false)); return $time[1] . substr($time[0], 2, 5); } }