/magmi/plugins/base/itemprocessors/columnmapper/000_columnmapper.php

<?php
/**
 * Class SampleItemProcessor
 * @author dweeves
 *
 * This class is a sample for item processing   
*/ 
class ColumnMappingItemProcessor extends Magmi_ItemProcessor
{

	protected $_dcols=array();
	
    public function getPluginInfo()
    {
        return array(
            "name" => "Column mapper",
            "author" => "Dweeves",
            "version" => "0.0.3",
        	"url"=>"http://sourceforge.net/apps/mediawiki/magmi/index.php?title=Column_mapper"
        );
    }
	
	/**
	 * you can add/remove columns for the item passed since it is passed by reference
	 * @param Magmi_Engine $mmi : reference to magmi engine(convenient to perform database operations)
	 * @param unknown_type $item : modifiable reference to item before import
	 * the $item is a key/value array with column names as keys and values as read from csv file.
	 * @return bool : 
	 * 		true if you want the item to be imported after your custom processing
	 * 		false if you want to skip item import after your processing
	 */
	
	public function processColumnList(&$cols,$params=null)
	{
		$icols=$cols;
		$ocols=array();
		$scols=array();
		foreach($icols as $cname)
		{

			if(isset($this->_dcols[$cname]))
			{
				$mlist=array_unique(explode(",",$this->_dcols[$cname]));
				$ncol=array_shift($mlist);
				$ocols[]=$ncol;
				if($ncol!=$cname)
				{
					$this->log("Replacing Column $cname by $ncol","startup");
				}
				if(count($mlist)>0)
				{					
					$scols=array_merge($scols,$mlist);
					$this->log("Replicating Column $cname to ".implode(",",$mlist),"startup");
				}
			}
			else
			{
				$ocols[]=$cname;
			}
		}
		$ocols=array_unique(array_merge($ocols,$scols));
		$cols=$ocols;
		return true;
	}
	
	public function processItemBeforeId(&$item,$params=null)
	{
		foreach($this->_dcols as $oname=>$mnames)
		{
			if(isset($item[$oname]))
			{
				$mapped=explode(",",$mnames);
				foreach($mapped as $mname)
				{
					$item[$mname]=$item[$oname];
				}
				if(!in_array($oname,$mapped))
				{
					unset($item[$oname]);
				}
			}
		}
		return true;
	}
	
	public function initialize($params)
	{
		foreach($params as $k=>$v)
		{
			if(preg_match_all("/^CMAP:(.*)$/",$k,$m) && $k!="CMAP:columnlist")
			{
				$colname=rawurldecode($m[1][0]);
				$this->_dcols[$colname]=$params[$k];
			}
		}
	}
	
	public function getPluginParams($params)
	{
		$pp=array();
		foreach($params as $k=>$v)
		{
			if(preg_match("/^CMAP:.*$/",$k))
			{
				$pp[$k]=$v;
			}
		}	
		return $pp;
	}
	
	static public function getCategory()
	{
		return "Input Data Preprocessing";
	}
}