<?php

/*

 * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between

 * Copyright (C) 2006-2009 Dan Fuhry

 * Installation package

 * sql_parse.php - SQL query splitter and templater

 *

 * This program is Free Software; you can redistribute and/or modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied

 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for details.

 */

/**

 * Parses a full file of SQL into individual queries. Also includes substitution (template) functions.

 * @package Enano

 * @subpackage Installer

 * @author Dan Fuhry

 */

class SQL_Parser

{

  /**

   * The SQL to be parsed.

   * @var string

   * @access private

   */

  private $sql_string;

  /**

   * Parsed SQL array

   * @var array

   * @access private

   */

  private $sql_array;

  /**

   * Template variables.

   * @var array

   * @access private

   */

  private $tpl_strings;

  /**

   * Constructor.

   * @param string If this contains newlines, it will be treated as the target SQL. If not, will be treated as a filename.

   * @param string If true, force as raw SQL, i.e. don't treat as a filename no matter what

   */

  public function __construct($sql, $force_file = false)

  {

    if ( strpos($sql, "\n") || $force_file )

    {

      $this->sql_string = $sql;

    }

    else

    {

      if ( file_exists($sql) )

      {

        $this->sql_string = @file_get_contents($sql);

        if ( empty($this->sql_string) )

        {

          throw new Exception('SQL file is blank or permissions are bad');

        }

      }

      else

      {

        throw new Exception('SQL file doesn\'t exist');

      }

    }

    $this->sql_array = false;

    $this->tpl_strings = array();

    // convert \r\n in the schema to \n, in case some FTP client or zip utility ran unix2dos for us

    // thanks to InvisGhost for reporting this error

    $this->sql_string = str_replace("\r\n", "\n", $this->sql_string);

  }

  /**

   * Sets template variables.

   * @param array Associative array of template variables to assign

   */

  public function assign_vars($vars)

  {

    if ( !is_array($vars) )

      return false;

    $this->tpl_strings = array_merge($this->tpl_strings, $vars);

  }

  /**

   * Internal function to parse the SQL.

   * @access private

   */

  private function parse_sql()

  {

    $this->sql_array = $this->sql_string;

    foreach ( $this->tpl_strings as $key => $value )

    {

      $this->sql_array = str_replace("{{{$key}}}", $value, $this->sql_array);

    }

    // Strip out comments

    $this->sql_array = explode("\n", $this->sql_array);

    foreach ( $this->sql_array as $i => $sql )

    {

      $query =& $this->sql_array[$i];

      $t = trim($query);

      if ( preg_match('/^(\#|--)/i', $t) )

      {

        unset($this->sql_array[$i]);

        unset($query);

      }

    }

    unset($query);

    $this->sql_array = array_values($this->sql_array);

    $this->sql_array = implode("\n", $this->sql_array);

    $this->sql_array = explode(";\n", trim($this->sql_array));

    foreach ( $this->sql_array as $i => $sql )

    {

      $query =& $this->sql_array[$i];

      $query = trim($query);

      if ( substr($query, ( strlen($query) - 1 ), 1 ) != ';' )

      {

        $query .= ';';

      }

    }

    unset($query);

  }

  /**

   * Returns the parsed array of SQL queries.

   * @param bool Optional. Defaults to false. If true, a parse is performed even if it already happened.

   * @return array

   */

  public function parse($force_reparse = false)

  {

    if ( !$this->sql_array || $force_reparse )

      $this->parse_sql();

    return $this->sql_array;

  }

}

?>