<?php

namespace App\Tests;

use PHPUnit\Framework\TestCase;

/**
 * The one file that is uploaded by FTP before anything else exists.
 *
 * It runs outside the application - no autoloader, no container, no framework - so it is tested
 * the way it runs: included, then called. Nothing here downloads anything; what is tested is the
 * part that decides whether something lands on the server, and where.
 */
final class SingleFileInstallerTest extends TestCase
{
    private string $target;

    public static function setUpBeforeClass(): void
    {
        // In a CLI process the file returns before it renders anything, so including it only
        // defines its functions.
        require_once \dirname(__DIR__).'/scripts/install.php';
    }

    protected function setUp(): void
    {
        $this->target = sys_get_temp_dir().'/kant-zip-'.bin2hex(random_bytes(6));
        mkdir($this->target, 0o775, true);
    }

    protected function tearDown(): void
    {
        foreach (glob($this->target.'/*') ?: [] as $entry) {
            is_dir($entry) ? self::removeDirectory($entry) : @unlink($entry);
        }
        @rmdir($this->target);
    }

    public function testTheVersionFolderIsStrippedAndTheTargetIsRespected(): void
    {
        $target = str_replace('\\', '/', $this->target);
        self::assertSame($target.'/public/index.php', kant_target_path('kantsites-1.2.0/public/index.php', $this->target));
        // Without the version folder the entry is taken as it is.
        self::assertSame($target.'/bin/console', kant_target_path('bin/console', $this->target));
    }

    /**
     * @param string $entry the archive entry a manipulated archive could contain
     */
    #[\PHPUnit\Framework\Attributes\DataProvider('dangerousEntries')]
    public function testNothingLandsOutsideTheTargetDirectory(string $entry): void
    {
        self::assertNull(kant_target_path($entry, $this->target), $entry.' darf nirgends landen.');
    }

    public static function dangerousEntries(): iterable
    {
        yield 'zwei Ebenen nach oben' => ['kantsites-1.2.0/../../.env'];
        yield 'direkt nach oben' => ['../evil.php'];
        yield 'mitten im Pfad' => ['kantsites-1.2.0/src/../../../evil.php'];
        yield 'absolut' => ['/etc/passwd'];
        yield 'Windows-Laufwerk' => ['C:/Windows/evil.php'];
        yield 'Rückwärtsschrägstrich' => ['kantsites-1.2.0\\..\\..\\evil.php'];
        yield 'Nullbyte' => ["kantsites-1.2.0/src/evil\0.php"];
        yield 'nur das Verzeichnis' => ['kantsites-1.2.0/'];
        yield 'leer' => [''];
    }

    public function testAnOrdinaryArchiveIsUnpackedAndAManipulatedOneIsNot(): void
    {
        $good = $this->archive(['kantsites-1.2.0/public/index.php' => '<?php echo 1;', 'kantsites-1.2.0/src/Kernel.php' => 'x']);
        self::assertSame(2, kant_unpack($good, $this->target));
        self::assertSame('<?php echo 1;', file_get_contents($this->target.'/public/index.php'));
        self::assertFileExists($this->target.'/src/Kernel.php');

        // An archive with an entry that points outside is refused - and the refusal happens while
        // unpacking, so what matters is that the file outside never appears.
        $evil = $this->archive(['kantsites-1.2.0/harmlos.txt' => 'ok', 'kantsites-1.2.0/../entwischt.txt' => 'böse']);
        try {
            kant_unpack($evil, $this->target);
            self::fail('Ein Eintrag außerhalb des Ziels muss zum Abbruch führen.');
        } catch (\RuntimeException $e) {
            self::assertStringContainsString('außerhalb', $e->getMessage());
        }
        self::assertFileDoesNotExist(\dirname($this->target).'/entwischt.txt');
    }

    public function testThePreflightNamesWhatIsMissing(): void
    {
        $checks = kant_checks($this->target);
        $labels = array_column($checks, 'label');
        self::assertContains('ZIP-Erweiterung', $labels);
        self::assertContains('Schreibrecht im Zielverzeichnis', $labels);

        // This copy comes from the repository, not from a release: no address, no checksum, and
        // it says so instead of downloading something.
        $unfinished = self::find($checks, 'Adresse und Prüfsumme eingetragen');
        self::assertFalse($unfinished['ok']);

        // An existing installation is not overwritten, not even partially.
        mkdir($this->target.'/public', 0o775, true);
        file_put_contents($this->target.'/public/index.php', 'x');
        self::assertFalse(self::find(kant_checks($this->target), 'Verzeichnis ist leer genug')['ok']);
    }

    private function archive(array $entries): string
    {
        $path = $this->target.'/../kant-archive-'.bin2hex(random_bytes(4)).'.zip';
        $zip = new \ZipArchive();
        $zip->open($path, \ZipArchive::CREATE | \ZipArchive::OVERWRITE);
        foreach ($entries as $name => $content) {
            $zip->addFromString($name, $content);
        }
        $zip->close();
        self::assertFileExists($path);
        register_shutdown_function(static fn () => @unlink($path));

        return $path;
    }

    private static function find(array $checks, string $label): array
    {
        foreach ($checks as $check) {
            if ($check['label'] === $label) {
                return $check;
            }
        }
        self::fail('Prüfung fehlt: '.$label);
    }

    private static function removeDirectory(string $path): void
    {
        foreach (scandir($path) ?: [] as $entry) {
            if ('.' !== $entry && '..' !== $entry) {
                is_dir($path.'/'.$entry) ? self::removeDirectory($path.'/'.$entry) : @unlink($path.'/'.$entry);
            }
        }
        @rmdir($path);
    }
}