<?php
/**
 * Crystal DBAL
 *
 * An open source application for database manipulation
 *
 * @package		Crystal DBAL
 * @author		Martin Rusev
 * @link		http://crystal.martinrusev.net
 * @since		Version 0.1
 * @version     0.1
 */

// ------------------------------------------------------------------------
class Crystal_Query_Postgres_Groupby
{

    

    function __construct($method, $groupby)
    {
    	
		
	 
		$this->groupby = '';
			
		if(is_array($groupby) && !empty($groupby))
		{
			
				$this->groupby = " GROUP BY ";	
	
				/** WORKS FOR ARRAYS group_by(array('product_id', 'category_id')) **/
				if(isset($groupby[1]))
				{
						
			      	end($groupby);
				    $last_element = key($groupby);
				    reset($groupby);
				    
				    
				    foreach($groupby as $key => $value)
				    {
				    	
				    	$this->groupby  .= Crystal_Helper_Postgres::sanitize_string($value); 
			            
				    	if($key != $last_element)
				    	{
				    		$this->groupby  .= ' , ';
				    		
				    	}
			
			        }
					
				}
				else
				{		$filtered_params = Crystal_Parser_String::parse($groupby[0]);
				
						if(is_string($filtered_params))
						{
							$this->groupby  .= Crystal_Helper_Postgres::sanitize_string($filtered_params);
						}
						elseif(is_array($filtered_params) && !empty($filtered_params))
						{
							
							end($filtered_params);
							$last_element = key($filtered_params);
							reset($filtered_params);
							
							
							foreach($filtered_params as $key => $value)
							{
								
								$this->groupby  .= Crystal_Helper_Postgres::sanitize_string($value);
								
								if($key != $last_element)
								{
									$this->groupby .= ' , ';
								}
								
							}
							
							
						}
						else
						{
							throw new Crystal_Query_Exception('Invalid parameters in order_by function');
						}
											
					
				}	
	
	          
	        }
    	
		
      
    }

    public function __toString() 
	{
        return $this->groupby;
    }
    
    
}