silverstripe-cms/code/Model/SiteTreeLinkTracking_Parser.php

<?php
namespace SilverStripe\CMS\Model;

use Director;
use SilverStripe\ORM\DataObject;
use SS_HTMLValue;

/**
 * A helper object for extracting information about links.
 */
class SiteTreeLinkTracking_Parser
{

	/**
	 * Finds the links that are of interest for the link tracking automation. Checks for brokenness and attaches
	 * extracted metadata so consumers can decide what to do with the DOM element (provided as DOMReference).
	 *
	 * @param SS_HTMLValue $htmlValue Object to parse the links from.
	 * @return array Associative array containing found links with the following field layout:
	 *        Type: string, name of the link type
	 *        Target: any, a reference to the target object, depends on the Type
	 *        Anchor: string, anchor part of the link
	 *        DOMReference: DOMElement, reference to the link to apply changes.
	 *        Broken: boolean, a flag highlighting whether the link should be treated as broken.
	 */
	public function process(SS_HTMLValue $htmlValue)
	{
		$results = array();

		$links = $htmlValue->getElementsByTagName('a');
		if (!$links) {
			return $results;
		}

		foreach ($links as $link) {
			if (!$link->hasAttribute('href')) {
				continue;
			}

			$href = Director::makeRelative($link->getAttribute('href'));

			// Definitely broken links.
			if ($href == '' || $href[0] == '/') {
				$results[] = array(
					'Type' => 'broken',
					'Target' => null,
					'Anchor' => null,
					'DOMReference' => $link,
					'Broken' => true
				);

				continue;
			}

			// Link to a page on this site.
			$matches = array();
			if (preg_match('/\[sitetree_link(?:\s*|%20|,)?id=(?<id>[0-9]+)\](#(?<anchor>.*))?/i', $href, $matches)) {
				$page = DataObject::get_by_id('SilverStripe\\CMS\\Model\\SiteTree', $matches['id']);
				$broken = false;

				if (!$page) {
					// Page doesn't exist.
					$broken = true;
				} else {
					if (!empty($matches['anchor'])) {
						$anchor = preg_quote($matches['anchor'], '/');

						if (!preg_match("/(name|id)=\"{$anchor}\"/", $page->Content)) {
							// Broken anchor on the target page.
							$broken = true;
						}
					}
				}

				$results[] = array(
					'Type' => 'sitetree',
					'Target' => $matches['id'],
					'Anchor' => empty($matches['anchor']) ? null : $matches['anchor'],
					'DOMReference' => $link,
					'Broken' => $broken
				);

				continue;
			}

			// Link to a file on this site.
			$matches = array();
			if (preg_match('/\[file_link(?:\s*|%20|,)?id=(?<id>[0-9]+)/i', $href, $matches)) {
				$results[] = array(
					'Type' => 'file',
					'Target' => $matches['id'],
					'Anchor' => null,
					'DOMReference' => $link,
					'Broken' => !DataObject::get_by_id('File', $matches['id'])
				);

				continue;
			}

			// Local anchor.
			$matches = array();
			if (preg_match('/^#(.*)/i', $href, $matches)) {
				$anchor = preg_quote($matches[1], '#');
				$results[] = array(
					'Type' => 'localanchor',
					'Target' => null,
					'Anchor' => $matches[1],
					'DOMReference' => $link,
					'Broken' => !preg_match("#(name|id)=\"{$anchor}\"#", $htmlValue->getContent())
				);

				continue;
			}

		}

		// Find all [image ] shortcodes (will be inline, not inside attributes)
		$content = $htmlValue->getContent();
		if (preg_match_all('/\[image([^\]]+)\bid=(["])?(?<id>\d+)\D/i', $content, $matches)) {
			foreach ($matches['id'] as $id) {
				$results[] = array(
					'Type' => 'image',
					'Target' => (int)$id,
					'Anchor' => null,
					'DOMReference' => null,
					'Broken' => !DataObject::get_by_id('Image', (int)$id)
				);
			}
		}
		return $results;
	}

}