<?php
/**
* Single quote string status for the scanner
*
* @license http://www.opensource.org/licenses/mit-license.php The MIT License
* @copyright Copyright 2010-2014 PhpCss Team
*/

namespace PhpCss\Scanner\Status\Text {

  use PhpCss\Scanner;

  /**
  * Single quote string status for the scanner
  */
  class Single extends Scanner\Status {

    /**
    * Try to get token in buffer at offset position.
    *
    * @param string $buffer
    * @param integer $offset
    * @return Scanner\Token
    */
    public function getToken(string $buffer, int $offset): ?Scanner\Token {
      if ("'" === substr($buffer, $offset, 1)) {
        return new Scanner\Token(
          Scanner\Token::SINGLEQUOTE_STRING_END, "'", $offset
        );
      }
      $tokenString = substr($buffer, $offset, 2);
      if ("\\'" === $tokenString || '\\\\' === $tokenString) {
        return new Scanner\Token(
           Scanner\Token::STRING_ESCAPED_CHARACTER, $tokenString, $offset
        );
      }
      $tokenString = $this->matchPattern(
        $buffer, $offset, '([^\\\\\']+)S'
      );
      if (!empty($tokenString)) {
        return new Scanner\Token(
          Scanner\Token::STRING_CHARACTERS, $tokenString, $offset
        );
      }
      return NULL;
    }

    /**
    * Check if token ends status
    *
    * @param Scanner\Token $token
    * @return boolean
    */
    public function isEndToken(Scanner\Token $token): bool {
      return (
        $token->type === Scanner\Token::SINGLEQUOTE_STRING_END
      );
    }

    /**
    * Get new (sub)status if needed.
    *
    * Returns always NULL, because a string never has a sub status
    *
    * @param Scanner\Token $token
    * @return Scanner\Status|NULL
    */
    public function getNewStatus(Scanner\Token $token): ?Scanner\Status {
      return NULL;
    }
  }
}