<?php
declare(strict_types=1);
namespace Jfcherng\Diff\Renderer\Html\LineRenderer;
use Jfcherng\Diff\Renderer\RendererConstant;
use Jfcherng\Diff\SequenceMatcher;
use Jfcherng\Diff\Utility\ReverseIterator;
use Jfcherng\Diff\Utility\Str;
use Jfcherng\Utility\MbString;
final class Word extends AbstractLineRenderer
{
/**
* {@inheritdoc}
*
* @return static
*/
public function render(MbString $mbOld, MbString $mbNew): LineRendererInterface
{
static $splitRegex = '/([' . RendererConstant::PUNCTUATIONS_RANGE . '])/uS';
static $dummyHtmlClosure = RendererConstant::HTML_CLOSURES[0] . RendererConstant::HTML_CLOSURES[1];
$pregFlag = \PREG_SPLIT_DELIM_CAPTURE | \PREG_SPLIT_NO_EMPTY;
$oldWords = $mbOld->toArraySplit($splitRegex, -1, $pregFlag);
$newWords = $mbNew->toArraySplit($splitRegex, -1, $pregFlag);
$hunk = $this->getChangedExtentSegments($oldWords, $newWords);
// reversely iterate hunk
foreach (ReverseIterator::fromArray($hunk) as [$op, $i1, $i2, $j1, $j2]) {
if ($op & (SequenceMatcher::OP_REP | SequenceMatcher::OP_DEL)) {
$oldWords[$i1] = RendererConstant::HTML_CLOSURES[0] . $oldWords[$i1];
$oldWords[$i2 - 1] .= RendererConstant::HTML_CLOSURES[1];
// insert dummy HTML closure to ensure there are always
// the same amounts of HTML closures in $oldWords and $newWords
// thus, this should make that "wordGlues" work correctly
// @see https://github.com/jfcherng/php-diff/pull/25
if ($op === SequenceMatcher::OP_DEL) {
array_splice($newWords, $j1, 0, [$dummyHtmlClosure]);
}
}
if ($op & (SequenceMatcher::OP_REP | SequenceMatcher::OP_INS)) {
$newWords[$j1] = RendererConstant::HTML_CLOSURES[0] . $newWords[$j1];
$newWords[$j2 - 1] .= RendererConstant::HTML_CLOSURES[1];
if ($op === SequenceMatcher::OP_INS) {
array_splice($oldWords, $i1, 0, [$dummyHtmlClosure]);
}
}
}
if (!empty($hunk) && !empty($this->rendererOptions['wordGlues'])) {
$regexGlues = array_map(
static fn (string $glue): string => preg_quote($glue, '/'),
$this->rendererOptions['wordGlues'],
);
$gluePattern = '/^(?:' . implode('|', $regexGlues) . ')+$/uS';
$this->glueWordsResult($oldWords, $gluePattern);
$this->glueWordsResult($newWords, $gluePattern);
}
$mbOld->set(implode('', $oldWords));
$mbNew->set(implode('', $newWords));
return $this;
}
/**
* Beautify diff result by glueing words.
*
* What this function does is basically making
* ["<diff_begin>good<diff_end>", "-", "<diff_begin>looking<diff_end>"]
* into
* ["<diff_begin>good", "-", "looking<diff_end>"].
*
* @param array $words the words
* @param string $gluePattern the regex to determine a string is purely glue or not
*/
protected function glueWordsResult(array &$words, string $gluePattern): void
{
/** @var int index of the word which has the trailing closure */
$endClosureIdx = -1;
foreach ($words as $idx => &$word) {
if ($word === '') {
continue;
}
if ($endClosureIdx < 0) {
if (Str::endsWith($word, RendererConstant::HTML_CLOSURES[1])) {
$endClosureIdx = $idx;
}
} elseif (Str::startsWith($word, RendererConstant::HTML_CLOSURES[0])) {
$words[$endClosureIdx] = substr($words[$endClosureIdx], 0, -\strlen(RendererConstant::HTML_CLOSURES[1]));
$word = substr($word, \strlen(RendererConstant::HTML_CLOSURES[0]));
$endClosureIdx = $idx;
} elseif (!preg_match($gluePattern, $word)) {
$endClosureIdx = -1;
}
}
}
}