<?php

declare(strict_types=1);

namespace Tests\Architecture;

use Tests\Architecture\Support\ArchitectureTestCase;

final class SupportGovernanceTest extends ArchitectureTestCase
{
    /** @var list<string> */
    private const APPROVED_SUPPORT_TOP_LEVEL_ENTRIES = [
        'Exception',
        'Util',
    ];

    /** @var list<string> */
    private const APPROVED_SUPPORT_FILES = [
        'Exception/NotFoundException.php',
        'Util/DateParser.php',
        'Util/SlugHelper.php',
    ];

    public function testSupportUsesOnlyApprovedTopLevelEntries(): void
    {
        $supportPath = $this->projectPath('src/Kernel/Support');
        self::assertDirectoryExists($supportPath);

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

        self::assertSame(
            self::APPROVED_SUPPORT_TOP_LEVEL_ENTRIES,
            $entries,
            'Kernel/Support is frozen by default: only explicitly approved subdirectories may exist.',
        );
    }

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

        $files = [];
        foreach ($iterator as $fileInfo) {
            if (!$fileInfo->isFile() || $fileInfo->getExtension() !== 'php') {
                continue;
            }

            $files[] = substr($fileInfo->getPathname(), strlen($supportPath) + 1);
        }

        sort($files);

        self::assertSame(
            self::APPROVED_SUPPORT_FILES,
            $files,
            'Any new file under Kernel/Support must be a deliberate architectural decision: update the allow list, tests and documentation together.',
        );
    }

    public function testSupportStaysIndependentFromFeatureModulesAndFrameworks(): void
    {
        $this->assertFilesDoNotReferenceFragments(
            $this->phpFilesUnder('src/Kernel/Support'),
            array_merge(
                self::APPLICATION_NAMESPACES,
                self::INFRASTRUCTURE_NAMESPACES,
                self::UI_NAMESPACES,
                self::FRAMEWORK_NAMESPACE_FRAGMENTS,
                self::HTTP_MESSAGE_DEPENDENCIES,
            ),
            'Kernel/Support must stay pure, transverse and framework-agnostic',
        );
    }

    public function testSupportClassesAreFinal(): void
    {
        foreach ($this->phpFilesUnder('src/Kernel/Support') as $file) {
            $code = $this->normalizedCode($file);

            self::assertTrue(
                str_contains($code, 'finalclass'),
                $this->fileRuleMessage('Kernel/Support classes must be final to avoid becoming extension points by accident', $file),
            );
        }
    }
}