silverstripe-cms/tasks/MigrateSiteTreeLinkingTask.php

<?php
/**
 * Rewrites plain internal HTML links into shortcode form, using existing link tracking information.
 *
 * @package cms
 * @subpackage tasks
 */
class MigrateSiteTreeLinkingTask extends BuildTask {

	protected $title = 'Migrate SiteTree Linking Task';

	protected $description = 'Rewrites plain internal HTML links into shortcode form, using existing link tracking information.';

	public function run($request) {
		$pages = 0;
		$links = 0;

		$linkedPages = new DataList('SiteTree');
		$linkedPages = $linkedPages->innerJoin('SiteTree_LinkTracking', '"SiteTree_LinkTracking"."SiteTreeID" = "SiteTree"."ID"');
		if($linkedPages) foreach($linkedPages as $page) {
			$tracking = DB::prepared_query(
				'SELECT "ChildID", "FieldName" FROM "SiteTree_LinkTracking" WHERE "SiteTreeID" = ?',
				array($page->ID)
			)->map();

			foreach($tracking as $childID => $fieldName) {
				$linked = DataObject::get_by_id('SiteTree', $childID);

				// TOOD: Replace in all HTMLText fields
				$page->Content = preg_replace (
					"/href *= *([\"']?){$linked->URLSegment}\/?/i",
					"href=$1[sitetree_link,id={$linked->ID}]",
					$page->Content,
					-1,
					$replaced
				);

				if($replaced) {
					$links += $replaced;
				}
			}

			$page->write();
			$pages++;
		}

		echo "Rewrote $links link(s) on $pages page(s) to use shortcodes.\n";
	}

}