SilverStripe\View\Parsers\Diff

Complexity

Total Complexity

45

Size/Duplication

Total Lines	188
Duplicated Lines	0 %

Importance

Changes

0

3 Methods

Rating	Name	Duplication	Size	Complexity
A	cleanHTML()	0	23	5
F	compareHTML()	0	100	26
C	getHTMLChunks()	0	35	14

<?php

namespace SilverStripe\View\Parsers;

use InvalidArgumentException;
use SilverStripe\Core\Convert;
use SilverStripe\Core\Injector\Injector;

require_once 'difflib/difflib.php';

/**
 * Class representing a 'diff' between two sequences of strings.
 */
class Diff extends \Diff
{
    public static $html_cleaner_class = null;

    /**
     *  Attempt to clean invalid HTML, which messes up diffs.
     *  This cleans code if possible, using an instance of HTMLCleaner
     *
     *  NB: By default, only extremely simple tidying is performed,
     *  by passing through DomDocument::loadHTML and saveXML
     *
     * @param string $content HTML content
     * @param HTMLCleaner $cleaner Optional instance of a HTMLCleaner class to
     *    use, overriding self::$html_cleaner_class
     * @return mixed|string
     */
    public static function cleanHTML($content, $cleaner = null)
    {
        if (!$cleaner) {
            if (self::$html_cleaner_class && class_exists(self::$html_cleaner_class)) {
                $cleaner = Injector::inst()->create(self::$html_cleaner_class);
            } else {
                //load cleaner if the dependent class is available
                $cleaner = HTMLCleaner::inst();
            }
        }

        if ($cleaner) {
            $content = $cleaner->cleanHTML($content);
        } else {
            // At most basic level of cleaning, use DOMDocument to save valid XML.
            $doc = HTMLValue::create($content);
            $content = $doc->getContent();
        }

        // Remove empty <ins /> and <del /> tags because browsers hate them
        $content = preg_replace('/<(ins|del)[^>]*\/>/', '', $content);

        return $content;
    }

    /**
     * @param string $from
     * @param string $to
     * @param bool $escape
     * @return string
     */
    public static function compareHTML($from, $to, $escape = false)
    {
        // First split up the content into words and tags
        $set1 = self::getHTMLChunks($from);
        $set2 = self::getHTMLChunks($to);

        // Diff that
        $diff = new Diff($set1, $set2);

        $tagStack[1] = $tagStack[2] = 0;

$tagStack was never initialized. Although not strictly required by PHP, it is generally a good practice to add $tagStack = array(); before regardless.

        $rechunked[1] = $rechunked[2] = array();

$rechunked was never initialized. Although not strictly required by PHP, it is generally a good practice to add $rechunked = array(); before regardless.

        // Go through everything, converting edited tags (and their content) into single chunks.  Otherwise
        // the generated HTML gets crusty
        foreach ($diff->edits as $edit) {
            $lookForTag = false;
            $stuffFor = [];
            switch ($edit->type) {
                case 'copy':
                    $lookForTag = false;
                    $stuffFor[1] = $edit->orig;
                    $stuffFor[2] = $edit->orig;
                    break;

                case 'change':
                    $lookForTag = true;
                    $stuffFor[1] = $edit->orig;
                    $stuffFor[2] = $edit->final;
                    break;

                case 'add':
                    $lookForTag = true;
                    $stuffFor[1] = null;
                    $stuffFor[2] = $edit->final;
                    break;

                case 'delete':
                    $lookForTag = true;
                    $stuffFor[1] = $edit->orig;
                    $stuffFor[2] = null;
                    break;
            }

            foreach ($stuffFor as $listName => $chunks) {
                if ($chunks) {
                    foreach ($chunks as $item) {
                        // $tagStack > 0 indicates that we should be tag-building
                        if ($tagStack[$listName]) {
                            $rechunked[$listName][sizeof($rechunked[$listName])-1] .= ' ' . $item;
                        } else {
                            $rechunked[$listName][] = $item;
                        }

                        if ($lookForTag
                            && !$tagStack[$listName]
                            && isset($item[0])
                            && $item[0] == "<"
                            && substr($item, 0, 2) != "</"
                        ) {
                            $tagStack[$listName] = 1;
                        } elseif ($tagStack[$listName]) {
                            if (substr($item, 0, 2) == "</") {
                                $tagStack[$listName]--;
                            } elseif (isset($item[0]) && $item[0] == "<") {
                                $tagStack[$listName]++;
                            }
                        }
                    }
                }
            }
        }

        // Diff the re-chunked data, turning it into maked up HTML
        $diff = new Diff($rechunked[1], $rechunked[2]);
        $content = '';
        foreach ($diff->edits as $edit) {
            $orig = ($escape) ? Convert::raw2xml($edit->orig) : $edit->orig;
            $final = ($escape) ? Convert::raw2xml($edit->final) : $edit->final;

            switch ($edit->type) {
                case 'copy':
                    $content .= " " . implode(" ", $orig) . " ";

It seems like $orig can also be of type string; however, parameter $pieces of implode() does only seem to accept array, maybe add an additional type check?

                    break;

                case 'change':
                    $content .= " <ins>" . implode(" ", $final) . "</ins> ";
                    $content .= " <del>" . implode(" ", $orig) . "</del> ";
                    break;

                case 'add':
                    $content .= " <ins>" . implode(" ", $final) . "</ins> ";
                    break;

                case 'delete':
                    $content .= " <del>" . implode(" ", $orig) . "</del> ";
                    break;
            }
        }

        return self::cleanHTML($content);
    }

    /**
     * @param string|bool|array $content If passed as an array, values will be concatenated with a comma.
     * @return array
     */
    public static function getHTMLChunks($content)
    {
        if ($content && !is_string($content) && !is_array($content) && !is_numeric($content) && !is_bool($content)) {

The condition is_bool($content) is always true.

            throw new InvalidArgumentException('$content parameter needs to be a string or array');
        }
        if (is_bool($content)) {
            // Convert boolean to strings
            $content = $content ? "true" : "false";
        }
        if (is_array($content)) {
            $content = array_filter($content, 'is_scalar');
            // Convert array to CSV
            $content = implode(',', $content);
        }

        $content = str_replace(array("&nbsp;", "<", ">"), array(" "," <", "> "), $content);
        $candidateChunks = preg_split("/[\t\r\n ]+/", $content);
        $chunks = [];
        for ($i = 0; $i < count($candidateChunks); $i++) {

It seems like $candidateChunks can also be of type false; however, parameter $var of count() does only seem to accept Countable|array, maybe add an additional type check?

It seems like you are calling the size function count() as part of the test condition. You might want to compute the size beforehand, and not on each iteration.

            $item = $candidateChunks[$i];
            if (isset($item[0]) && $item[0] == "<") {
                $newChunk = $item;
                while ($item[strlen($item)-1] != ">") {
                    if (++$i >= count($candidateChunks)) {
                        break;
                    }
                    $item = $candidateChunks[$i];
                    $newChunk .= ' ' . $item;
                }
                $chunks[] = $newChunk;
            } else {
                $chunks[] = $item;
            }
        }
        return $chunks;
    }
}