mage_update.php

<?php
	/* 
	** mage_update:
	** Relies on Magento's Varien Object __call() magic method to save to database attribute fields.
	** Lack of error-handling™ because this is a batch script and Magento is in Developer Mode.
	** Note that this is called in one hell of a loop (~3.4 million iterations), so keep it relatively speedy.
	** 
	** lower_case_with_underscores becomes CamelCase
	** UPPERCASE becomes Capitalized, yadda yadda.
	**
	** @param (string) $new: new SKU Code Input
	** @param (int) $id: Product ID (entity_id)
	** @return void
	*/
	function mage_update($new, $id) {
		$model = Mage::Model('catalog/product')->load($id);
		$path = $model->getImage();
		$path_small = $model->getSmallImage();
		$thumbnail = $model->getThumbnail();
		$old = $model->getSku();
		
		$ext = end(explode(".", $path));
		if ($path == $ext) throw new Exception("Invalid File (Renaming): $path ($new)"); // TODO: check all paths
		
		/* Warning: Make *sure* the Magento cache is enabled while renaming when running this on live.
		 * 'round these parts; we don't need no stinkin' maintenance time. */
		$model->setImage("/ws/$sku.$ext"); // hardcoded for now. TODO: fix
		$model->setSmallImage("/ws/{$sku}_small.$ext");
		$model->setThumbnail("/ws/thumb_$sku.$ext");
		$model->setSku($new)->setOldSku($old);
		
		$dir = "media/catalog/product"; // hardcoding, ho! TODO: fix
		
		// TODO: check file_exists(). 
		// TODO: Fix naive assumption that all files are different here (they're not always)
		rename($dir.$path, "$dir/$sku.$ext");
		rename($dir.$path_small, "$dir/{$sku}_small.$ext");
		rename($dir.$thumbnail, "$dir/thumb_$sku.$ext");
	}
  ?>