<?php defined('SYSPATH') OR die('No direct access allowed.');

class Database extends Database_Core
{
  public function __construct($config = array())
  {
    parent::__construct($config);
  }

  /**
   * Selects the column names for a database query.
   *
   * @param   string  string or array of column names to select
   * @return  Database_Core  This Database object.
   */
  public function select($sql = '*')
  {
    if (func_num_args() > 1)
    {
      $sql = func_get_args();
    }
    elseif (is_string($sql))
    {
      $sql = explode(',', $sql);
    }
    else
    {
      $sql = (array) $sql;
    }

    foreach ($sql as $val)
    {
      if (($val = trim($val)) === '') continue;

      if (strpos($val, '(') === FALSE AND $val !== '*')
      {
        if (preg_match('/^DISTINCT\s++(.+)$/i', $val, $matches))
        {
          // Only prepend with table prefix if table name is specified
          $val = (strpos($matches[1], '.') !== FALSE) ? $this->config['table_prefix'].$matches[1] : $matches[1];

          $this->distinct = TRUE;
        }
        else
        {

          $val = (strpos($val, '.') !== FALSE) ? $this->config['table_prefix'].$val : $val;
        }
        $val = $this->driver->escape_column($val);
      }

      # RK: table_prefix & escape_column for COUNT($value) AS $alias
      if (stripos($val, 'count(') !== FALSE AND stripos($val, 'count(*)') === FALSE)
      {

        $val = preg_replace('/(count|COUNT)\((.+)\)/','$2', $val);
        $val = (strpos($val, '.') !== FALSE) ? $this->config['table_prefix'].$val : $val;
        $val = $this->driver->escape_column($val);
        if(stripos($val, ' AS ') !== FALSE)
        {
          list($column, $alias) = explode(' AS ', $val);
          $val = "COUNT($column) AS $alias";
        }
        else
        {
          $val = "COUNT($val)";
        }
      }
      $this->select[] = $val;
    }

    return $this;
  }


}