FrxSyntaxEngine.inc in Forena Reports 6

FrXSytnaxEngine defines how regular expression procesing/token substitution takes place. It includes support for passing in a formatter oobject that will escape strings properly before substituting them.

File

FrxSyntaxEngine.inc

<?php

// $Id$

/**
 * @file
 * FrXSytnaxEngine defines how regular expression procesing/token substitution takes place.
 * It includes support for passing in a formatter oobject that will escape strings properly
 * before substituting them.
 *
 */
define('FRX_TOKEN_EXP', '/\\{[^\\n^\\r^}]+}/');
define('FRX_SQL_TOKEN', '/:([a-z]|[0-9]|{A-Z]|[_])+/');
class FrxSyntaxEngine {
  private $tpattern;
  private $trim_chars;
  private $formatter;

  // Object used to format the data
  private $data_stack;
  private $data_sources;

  /**
   * Class for doing syntax replacements;
   * @param $regexp
   * @return unknown_type
   */
  public function __construct($regexp, $trim, $formatter = NULL) {
    $this->tpattern = $regexp;
    $this->trim_chars = $trim;
    if (is_object($formatter)) {
      $this->formatter = $formatter;
    }
    $this->data_stack = array();
    $this->data_sources = array();
  }

  /**
   * Push a data context onto the data stacks
   * to make sure that we can address these using an
   * appropriate syntax.  I think we don't need data_stack
   * but i'm holding it there in case we develop a "relative" path syntax.
   * @param $data
   * @param $id
   * @return unknown_type
   */
  public function push_data($data, $id = '') {
    $this->data_stack[] = $data;
    if ($id) {
      $this->data_sources[$id] = $data;
    }
  }

  /**
   * Remove data from the data stack.  This will make data unavaiable
   * when we leave the context of the current nested reports.
   * @param $id
   * @return unknown_type
   */
  public function pop_data($id = '') {
    array_pop($this->data_stack);
    if ($id) {
      unset($this->data_stack[$id]);
    }
  }

  /**
   * Provides an api to the {=xpath} syntax that can be used
   * to evaluat expressions such as sum and count in a report.  We
   * need to use the DOM object here, because this method isn't exposed
   * with simplexml.
   *
   * @param $xml
   * @param $path
   * @return unknown_type
   */
  protected function simplexml_evaluate($xml, $path) {
    $dom_node = dom_import_simplexml($xml);
    $dom_doc = new DOMDocument('');
    $dom_node = $dom_doc
      ->importNode($dom_node, TRUE);
    $dom_doc
      ->appendChild($dom_node);

    // Do we also need to call AppendChild?
    $xpath = new DOMXpath($dom_doc);
    $ret = $xpath
      ->evaluate($path, $dom_node);
    return $ret;
  }

  /**
   * Get the value from the data.
   * This is used by token_replace method to extract the data based on the path provided.
   * @param $data
   * @param $key
   * @return unknown_type
   */
  protected function get_value($key, $raw = FALSE) {
    $retvar = '';

    // Determne which $data var we're going to get
    $data = array();
    if ($this->data_stack) {
      $i = count($this->data_stack) - 1;
      $data = $this->data_stack[$i];
    }
    $raw_key = $key;

    // Determine if we have a . syntax for the id.
    if ($key && strpos($key, '.')) {
      @(list($id, $path) = explode('.', $key, 2));
      if ($data && isset($this->data_sources[$id])) {
        $data = $this->data_sources[$id];
        $key = $path;
      }
    }
    if (is_array($data)) {
      $retvar = @$data[$key];
    }
    elseif (is_object($data)) {
      if (strpos($key, '=') === 0) {
        $retvar = $this
          ->simplexml_evaluate($data, ltrim($key, '='));
      }
      else {
        $rows = $data
          ->xpath($key);
        $x = '';
        if ($rows) {
          $x = $rows[0];
        }
        if ($x) {
          $retvar = $x
            ->asXML();
        }

        // Check to see if there are child nodes
        // If so use asXML otherwise string cast.
        if ($retvar && strpos($retvar, '<') !== FALSE) {

          // Find the end of the first tag.
          $p = strpos($retvar, '>');
          $retvar = substr_replace($retvar, '', 0, $p + 1);
          $p = strrpos($retvar, '<', -1);
          $retvar = substr_replace($retvar, '', $p, strlen($retvar) - $p);
        }
        else {
          $retvar = (string) $x;
        }
      }
    }

    // Call the formatter object if neccessary
    $f = $this->formatter;
    if (!$raw && is_object($f) && method_exists($f, 'format')) {
      $retvar = $f
        ->format($retvar, $raw_key, $data);
    }
    $retvar = trim((string) $retvar);
    return $retvar;
  }

  /**
   *
   * @param $text text that needs replacing
   * @param $data
   * @return unknown_type
   */
  public function replace($text, $data = '', $raw = FALSE) {
    $match = array();
    $o_text = $text;

    // Put the data on the stack.
    if ($data) {
      $this
        ->push_data($data);
    }
    if (preg_match_all($this->tpattern, $o_text, $match)) {

      //list($params) = $match[1];
      $i = 0;
      foreach ($match[0] as $match_num => $token) {
        $path = trim($token, $this->trim_chars);
        $value = $this
          ->get_value($path, $raw);
        $pos = strpos($text, $token);
        if ($pos !== FALSE) {
          $text = substr_replace($text, $value, $pos, strlen($token));
        }
      }
    }
    if ($data) {
      $this
        ->pop_data();
    }
    return $text;
  }

  /**
   * List all of the tokens used in a piece of text, ignoring duplicates.
   *
   * @param string $text
   * @return array tokens contained in the text according to the regular expression.
   */
  public function tokens($text) {
    $match = array();
    $tokens = array();
    if (preg_match_all($this->tpattern, $text, $match)) {
      $i = 0;
      foreach ($match[0] as $match_num => $token) {
        $path = trim($token, $this->trim_chars);
        if (array_search($path, $tokens) === FALSE) {
          $tokens[] = $path;
        }
      }
    }
    return $tokens;
  }

  /**
   * Convert an object into an array
   * @param mixed $data
   * Iterates the object and builds an array of strings from it.
   * If the object appears to be an xml object and has an attributes
   * method, do the same for it.
   */
  public function object_to_array($data) {
    if (is_object($data)) {
      $ar = array();
      foreach ($data as $key => $value) {
        $ar[$key] = (string) $value;
      }
      if (method_exists($data, 'attributes')) {
        foreach ($data
          ->attributes() as $key => $value) {
          $ar[$key] = (string) $value;
        }
      }
      return $ar;
    }
    else {
      return $data;
    }
  }

}

Constants

Name	Description
FRX_SQL_TOKEN
FRX_TOKEN_EXP	@file FrXSytnaxEngine defines how regular expression procesing/token substitution takes place. It includes support for passing in a formatter oobject that will escape strings properly before substituting them.

Classes

Name	Description
FrxSyntaxEngine