<?php declare(strict_types=1);
/*
* This file is part of sebastian/diff.
*
* (c) Sebastian Bergmann <sebastian@phpunit.de>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace SebastianBergmann\Diff\Output;

/**
* Builds a diff string representation in a loose unified diff format
* listing only changes lines. Does not include line numbers.
*/
final class DiffOnlyOutputBuilder implements DiffOutputBuilderInterface
{
/**
* @var string
*/
private $header;

public function __construct(string $header = "--- Original\n+++ New\n")
{
$this->header = $header;
}

public function getDiff(array $diff): string
{
$buffer = \fopen('php://memory', 'r+b');

if ('' !== $this->header) {
\fwrite($buffer, $this->header);
if ("\n" !== \substr($this->header, -1, 1)) {
\fwrite($buffer, "\n");
}
}

foreach ($diff as $diffEntry) {
if ($diffEntry[1] === 1 /* ADDED */) {
\fwrite($buffer, '+' . $diffEntry[0]);
} elseif ($diffEntry[1] === 2 /* REMOVED */) {
\fwrite($buffer, '-' . $diffEntry[0]);
} elseif ($diffEntry[1] === 3 /* WARNING */) {
\fwrite($buffer, ' ' . $diffEntry[0]);

continue; // Warnings should not be tested for line break, it will always be there
} else { /* Not changed (old) 0 */
continue; // we didn't write the non changs line, so do not add a line break either
}

$lc = \substr($diffEntry[0], -1);
if ($lc !== "\n" && $lc !== "\r") {
\fwrite($buffer, "\n"); // \No newline at end of file
}
}

$diff = \stream_get_contents($buffer, -1, 0);
\fclose($buffer);

return $diff;
}
}