class Statement

class Statement extends StatementBase {
  
  /**
   * Holds the index position of named parameters.
   *
   * The mysqli driver only allows positional placeholders '?', whereas in
   * Drupal the SQL is generated with named placeholders ':name'. In order to
   * execute the SQL, the string containing the named placeholders is converted
   * to using positional ones, and the position (index) of each named
   * placeholder in the string is stored here.
   */
  protected array $paramsPositions;
  
  /**
   * Constructs a Statement object.
   *
   * @param \Drupal\Core\Database\Connection $connection
   *   Drupal database connection object.
   * @param \mysqli $clientConnection
   *   Client database connection object.
   * @param string $queryString
   *   The SQL query string.
   * @param array $driverOpts
   *   (optional) Array of query options.
   * @param bool $rowCountEnabled
   *   (optional) Enables counting the rows affected. Defaults to FALSE.
   */
  public function __construct(Connection $connection, \mysqli $clientConnection, string $queryString, protected array $driverOpts = [], bool $rowCountEnabled = FALSE) {
    parent::__construct($connection, $clientConnection, $queryString, $rowCountEnabled);
    $this->setFetchMode(FetchAs::Object);
  }
  
  /**
   * Returns the client-level database statement object.
   *
   * This method should normally be used only within database driver code.
   *
   * @return \mysqli_stmt
   *   The client-level database statement.
   */
  public function getClientStatement() : \mysqli_stmt {
    if ($this->hasClientStatement()) {
      assert($this->clientStatement instanceof \mysqli_stmt);
      return $this->clientStatement;
    }
    throw new \LogicException('\\mysqli_stmt not initialized');
  }
  
  /**
   * {@inheritdoc}
   */
  public function execute($args = [], $options = []) {
    if (isset($options['fetch'])) {
      if (is_string($options['fetch'])) {
        $this->setFetchMode(FetchAs::ClassObject, $options['fetch']);
      }
      else {
        $this->setFetchMode($options['fetch']);
      }
    }
    $startEvent = $this->dispatchStatementExecutionStartEvent($args ?? []);
    try {
      // Prepare the lower-level statement if it's not been prepared already.
      if (!$this->hasClientStatement()) {
        // Replace named placeholders with positional ones if needed.
        $this->paramsPositions = array_flip(array_keys($args));
        $converter = new NamedPlaceholderConverter();
        $converter->parse($this->queryString, $args);
        [$convertedQueryString, $args] = [
          $converter->getConvertedSQL(),
          $converter->getConvertedParameters(),
        ];
        $this->clientStatement = $this->clientConnection
          ->prepare($convertedQueryString);
      }
      else {
        // Transform the $args to positional.
        $tmp = [];
        foreach ($this->paramsPositions as $param => $pos) {
          $tmp[$pos] = $args[$param];
        }
        $args = $tmp;
      }
      // In mysqli, the results of the statement execution are returned in a
      // different object than the statement itself.
      $return = $this->getClientStatement()
        ->execute($args);
      $this->result = new Result($this->fetchMode, $this->fetchOptions, $this->getClientStatement()
        ->get_result(), $this->clientConnection);
      $this->markResultsetIterable($return);
    } catch (\Exception $e) {
      $this->dispatchStatementExecutionFailureEvent($startEvent, $e);
      throw $e;
    }
    $this->dispatchStatementExecutionEndEvent($startEvent);
    return $return;
  }

}