<?php

declare(strict_types=1);

namespace Tests\Architecture;

use Tests\Architecture\Support\ArchitectureTestCase;

final class KernelStructureTest extends ArchitectureTestCase
{
    public function testKernelUsesOnlyApprovedTopLevelEntries(): void
    {
        $sharedPath = $this->projectPath('src/Kernel');
        self::assertDirectoryExists($sharedPath);

        $entries = array_values(array_filter(scandir($sharedPath) ?: [], static fn (string $entry): bool => !in_array($entry, ['.', '..'], true)));
        sort($entries);

        self::assertSame([
            'Html',
            'Http',
            'Mail',
            'Pagination',
            'Persistence',
            'Runtime',
            'Support',
        ], $entries, 'Kernel must expose only approved transverse modules at top level.');
    }

    public function testKernelPathsDoNotUseFeatureModuleNames(): void
    {
        $sharedPath = $this->projectPath('src/Kernel');
        $iterator = new \RecursiveIteratorIterator(
            new \RecursiveDirectoryIterator($sharedPath, \FilesystemIterator::SKIP_DOTS),
            \RecursiveIteratorIterator::SELF_FIRST,
        );

        foreach ($iterator as $fileInfo) {
            $relativePath = substr($fileInfo->getPathname(), strlen($sharedPath) + 1);
            $pathSegments = preg_split('~/+~', $relativePath) ?: [];

            foreach ($pathSegments as $segment) {
                $name = pathinfo($segment, PATHINFO_FILENAME);

                foreach (self::FEATURE_MODULES as $module) {
                    self::assertFalse(
                        str_starts_with($name, $module),
                        sprintf('Kernel should not host feature-specific files or directories: %s', 'src/Kernel/' . $relativePath),
                    );
                }
            }
        }
    }
}