<?php

namespace App\Console\Commands;

use App\Utilities\QiniuPrivateUrlSigner;
use Illuminate\Console\Command;
use Illuminate\Contracts\Filesystem\Filesystem;
use Illuminate\Support\Facades\File;
use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Storage;
use RuntimeException;
use Throwable;

class SyncBusinessFilesToQiniu extends Command
{
    private const PROBE_CLEANUP_MAX_ATTEMPTS = 10;

    private const PROBE_CLEANUP_RETRY_DELAY_MICROSECONDS = 500_000;

    protected $signature = 'storage:business-files:sync
                            {--require-qiniu : Fail unless the private Qiniu backend is enabled}
                            {--probe-only : Verify private read/write/delete without copying retained files}
                            {--resync : Recheck every retained local business file}';

    protected $description = 'Verify private business storage and copy retained local uploads without deleting them';

    private string $markerPath;

    public function __construct()
    {
        parent::__construct();

        $this->markerPath = storage_path('app/.business-storage-qiniu-synced');
    }

    public function handle(): int
    {
        if (config('business_storage.driver') !== 'qiniu') {
            if ($this->option('require-qiniu')) {
                $this->components->error('生产业务文件存储尚未启用。');

                return self::FAILURE;
            }

            $this->components->info('当前使用本机业务文件存储，无需同步。');

            return self::SUCCESS;
        }

        if (! $this->hasCompleteCredentials()) {
            $this->components->error('生产业务文件存储凭据不完整。');

            return self::FAILURE;
        }

        try {
            $this->probeQiniu();

            if ($this->option('probe-only')) {
                $this->components->info('私有业务文件存储读写验证通过。');

                return self::SUCCESS;
            }

            $copied = 0;
            $skipped = 0;

            if ($this->option('resync') || ! File::exists($this->markerPath)) {
                [$copied, $skipped] = $this->syncRetainedLocalFiles();

                File::put(
                    $this->markerPath,
                    json_encode([
                        'completed_at' => now()->toIso8601String(),
                        'copied' => $copied,
                        'skipped' => $skipped,
                    ], JSON_UNESCAPED_SLASHES) . PHP_EOL
                );
            }

            $this->components->info(
                "私有业务文件存储可用；复制 {$copied} 个，复用 {$skipped} 个，本机原件保留。"
            );

            return self::SUCCESS;
        } catch (Throwable $e) {
            report($e);
            $this->components->error('私有业务文件存储验证或旧文件同步失败。');

            return self::FAILURE;
        }
    }

    private function hasCompleteCredentials(): bool
    {
        return (string) config('business_storage.qiniu.access_key') !== ''
            && (string) config('business_storage.qiniu.secret_key') !== '';
    }

    private function probeQiniu(): void
    {
        $disk = Storage::disk('business_uploads_qiniu');
        $path = '.health/storage-' . bin2hex(random_bytes(12)) . '.txt';
        $contents = bin2hex(random_bytes(24));

        try {
            if (! $disk->put($path, $contents, ['visibility' => 'private'])) {
                throw new RuntimeException('Business storage probe write failed.');
            }

            if ($disk->get($path) !== $contents) {
                throw new RuntimeException('Business storage probe read failed.');
            }

            $signer = app(QiniuPrivateUrlSigner::class);
            $unsignedResponse = Http::timeout(20)->head(
                $signer->unsignedUrlForPath($path)
            );
            if (! in_array($unsignedResponse->status(), [401, 403], true)) {
                throw new RuntimeException('Business storage is not private.');
            }

            $signedUrl = $signer->forPath($path);
            $response = Http::timeout(20)->head($signedUrl);
            if (! $response->successful()) {
                throw new RuntimeException('Business storage signed read failed.');
            }
        } finally {
            $disk->delete($path);
        }

        $this->confirmProbeCleanup($disk, $path);
    }

    private function confirmProbeCleanup(Filesystem $disk, string $path, ?callable $sleep = null): void
    {
        $sleep ??= static function (int $microseconds): void {
            usleep($microseconds);
        };

        for ($attempt = 0; $attempt < self::PROBE_CLEANUP_MAX_ATTEMPTS; $attempt++) {
            if (! $disk->exists($path)) {
                return;
            }

            if ($attempt < self::PROBE_CLEANUP_MAX_ATTEMPTS - 1) {
                $sleep(self::PROBE_CLEANUP_RETRY_DELAY_MICROSECONDS);
            }
        }

        throw new RuntimeException('Business storage probe cleanup failed.');
    }

    private function syncRetainedLocalFiles(): array
    {
        $source = Storage::disk('business_uploads_local');
        $target = Storage::disk('business_uploads_qiniu');
        $copied = 0;
        $skipped = 0;

        foreach ($source->allFiles() as $path) {
            $sourceSize = $source->size($path);

            if ($target->exists($path) && $target->size($path) === $sourceSize) {
                $skipped++;

                continue;
            }

            $stream = $source->readStream($path);
            if (! is_resource($stream)) {
                throw new RuntimeException('Unable to read retained local business file.');
            }

            try {
                if (! $target->put($path, $stream, ['visibility' => 'private'])) {
                    throw new RuntimeException('Unable to copy retained local business file.');
                }
            } finally {
                fclose($stream);
            }

            if (! $target->exists($path) || $target->size($path) !== $sourceSize) {
                throw new RuntimeException('Copied business file verification failed.');
            }

            $copied++;
        }

        return [$copied, $skipped];
    }
}