Small PHP-Script with GUI to unzip files in current directory

unzip.php

<?php

echo '<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css"><link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.3.0/css/font-awesome.min.css">';
echo '<div class="container" style="margin-top:50px;">';


if (!class_exists('ZipArchive')) {
	die("<h1>ZipArchive is not installed. Pleas echeck php.ini</h1>");
}

if ($_GET['delete_me'] == 'true') {
	unlink(__FILE__);
	echo "<div class='alert alert-success'>Bye Bye!</div>"; exit;
}

if ($_GET['unzip_all'] == 'true') {
	$files = glob('*.zip');

	foreach ($files as $file) {
		$zip = new ZipArchive();
		if ($res = $zip->open($file)) {
			$zip->extractTo('./');
			$zip->close();

			if ($_GET['delete'] == 'true') {
				unlink($file);
			}
		} else {
			echo "<div class='alert alert-danger'>Unzip failed!</div>";
		}

		echo "<div class='alert alert-success'>Unzip successful!</div>";
	}
}

if ($unzip_file = $_GET['unzip_file']) {
	$unzip_file = str_replace("/", "", $unzip_file);

	if (!is_readable($unzip_file)) {
		echo "<div class='alert alert-danger'>File cannot be opened!</div>";
	}

	if (stripos('..', $unzip_file)) {
		echo "<div class='alert alert-danger'>Illegal pattern!</div>";
	}

	$zip = new ZipArchive();
	if ($res = $zip->open($unzip_file)) {
		$zip->extractTo('./');
		$zip->close();
		echo "<div class='alert alert-success'>Unzip successful!</div>";

		if ($_GET['delete'] == 'true') {
			unlink($unzip_file);
		}
	} else {
		echo "<div class='alert alert-danger'>Unzip failed!</div>";
	}
}

echo "<h2>Zip-files in current dir</h2>";

$files = glob('*.zip');

echo "<table class='table table-striped'>";
foreach ($files as $file) {
	echo sprintf("<tr><td><b>%s</b></td> <td class='text-right'><div class='btn-group'><a href='?unzip_file=%s' class='btn btn-primary'>Unzip</a> <a href='?unzip_file=%s&delete=true' class='btn btn-danger'>Unzip &amp; delete</a></div></td></tr>", $file, $file, $file);
}
echo "</table>";

echo "<div class='text-right'><a href='?unzip_all=true'>Unzip all files</a> &bull; <a href='?unzip_all=true&delete=true'>Unzip and delete all files</a> &bull; <a href='?delete_me=true'>Delete this file</a></div>";

echo "<hr><div class='text-right small text-muted'>Copyright &copy; 2015 <a href='http://www.fabian-golle.de'>Fabian Golle IT</a>. All rights reserved.</a>";