<?php

declare(strict_types=1);

namespace App\Command;

use App\BusProNet\Model\XmlExportInfo;
use App\Model\BpnXmlSnapshotRefreshResult;
use App\Model\BpnXmlSyncTarget;
use App\Service\BpnXmlSnapshotRefreshManager;
use App\Service\BpnXmlSyncManager;
use League\Flysystem\FilesystemException;
use Psr\Log\LoggerInterface;
use Symfony\Component\Console\Attribute\AsCommand;
use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Command\LockableTrait;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Output\OutputInterface;
use Symfony\Component\Console\Style\SymfonyStyle;

#[AsCommand(
    name: 'app:bpn:xml-sync',
    description: 'Synchronizes XML export files from remote SFTP source to local storage'
)]
class BpnXmlSyncCommand extends Command
{
    use LockableTrait;

    public function __construct(
        private readonly BpnXmlSyncManager $syncManager,
        private readonly BpnXmlSnapshotRefreshManager $snapshotRefreshManager,
        private readonly LoggerInterface $logger,
    ) {
        parent::__construct();
    }

    protected function configure(): void
    {
        $this
            ->addOption('force', 'f', InputOption::VALUE_NONE, 'Force sync even if local data is up to date')
            ->addOption('dry-run', null, InputOption::VALUE_NONE, 'Check for updates without downloading');
    }

    protected function execute(InputInterface $input, OutputInterface $output): int
    {
        $io = new SymfonyStyle($input, $output);

        if (false === $this->lock('bpn_xml_sync')) {
            $io->warning('Sync is already running in another process');
            $this->logger->info('XML sync skipped: another instance is running');

            return Command::SUCCESS;
        }

        return $this->sync(
            (bool) $input->getOption('force'),
            (bool) $input->getOption('dry-run'),
            $io,
            $output,
        );
    }

    private function sync(bool $force, bool $dryRun, SymfonyStyle $io, OutputInterface $output): int
    {
        $totalSyncedCount = 0;
        $totalDeletedCount = 0;
        $hasSyncedFiles = false;
        $failedDatasets = [];
        $travelSynced = false;
        $travelRemoteTimestamp = null;
        $snapshotResult = null;
        $orphanedDeleted = null;

        foreach ($this->syncManager->getSyncTargets() as $target) {
            $targetResult = $this->syncTarget($target, $force, $dryRun, $io, $output);

            if ($targetResult['failed']) {
                $failedDatasets[] = $targetResult['dataset'];
            }

            if (false === $targetResult['synced']) {
                continue;
            }

            $hasSyncedFiles = true;
            $totalSyncedCount += $targetResult['updated'];
            $totalDeletedCount += $targetResult['deleted'];

            if ($targetResult['travelSynced']) {
                $travelSynced = true;
                $travelRemoteTimestamp = $targetResult['remoteTimestamp'];
            }
        }

        if (false === $dryRun && $hasSyncedFiles) {
            $invalidatedTags = $this->syncManager->invalidateCaches();
            $io->text(sprintf(
                'Invalidated %d cache tags',
                $invalidatedTags,
            ));
        }

        if (false === $dryRun && $travelSynced) {
            $io->section('Refreshing snapshots');
            $snapshotResult = $this->refreshSnapshots($io);
            if (null !== $snapshotResult) {
                $orphanedDeleted = $snapshotResult->orphanedDeleted;
            }
        }

        if ($dryRun) {
            return Command::SUCCESS;
        }

        if ($hasSyncedFiles) {
            $successMessage = sprintf(
                'Sync complete: %d files updated, %d files deleted',
                $totalSyncedCount,
                $totalDeletedCount
            );

            if (null !== $snapshotResult) {
                $successMessage .= sprintf(
                    ', snapshots: %d processed, %d failed',
                    $snapshotResult->processed,
                    $snapshotResult->failed
                );
            }

            if (null !== $orphanedDeleted) {
                $successMessage .= sprintf(', orphaned deleted: %d', $orphanedDeleted);
            }

            if ([] !== $failedDatasets) {
                $successMessage .= sprintf(', failed datasets: %s', implode(', ', $failedDatasets));
            }

            $logContext = [
                'files_updated' => $totalSyncedCount,
                'files_deleted' => $totalDeletedCount,
                'snapshots_processed' => $snapshotResult?->processed,
                'snapshots_failed' => $snapshotResult?->failed,
                'orphaned_deleted' => $orphanedDeleted,
                'remote_timestamp' => $travelRemoteTimestamp,
                'failed_datasets' => $failedDatasets,
            ];

            if ([] !== $failedDatasets) {
                $io->warning($successMessage);
                $this->logger->warning('XML sync completed with dataset errors', $logContext);
            } else {
                $io->success($successMessage);
                $this->logger->info('XML sync completed', $logContext);
            }

            return Command::SUCCESS;
        }

        if ([] !== $failedDatasets) {
            $io->warning(sprintf(
                'Sync completed with errors for: %s',
                implode(', ', $failedDatasets),
            ));
            $this->logger->warning('XML sync completed with dataset errors', [
                'failed_datasets' => $failedDatasets,
            ]);

            return Command::SUCCESS;
        }

        $io->success('No sync required');

        return Command::SUCCESS;
    }

    /**
     * @return array{dataset: string, synced: bool, failed: bool, updated: int, deleted: int, travelSynced: bool, remoteTimestamp: ?string}
     */
    private function syncTarget(
        BpnXmlSyncTarget $target,
        bool $force,
        bool $dryRun,
        SymfonyStyle $io,
        OutputInterface $output,
    ): array {
        $datasetName = $target->name;

        $remoteInfo = $this->syncManager->readRemoteInfo($target->source, $datasetName);
        if (null === $remoteInfo) {
            $io->warning(sprintf(
                '[%s] Remote info unavailable - will retry on next scheduled run',
                $datasetName
            ));

            return [
                'dataset' => $datasetName,
                'synced' => false,
                'failed' => false,
                'updated' => 0,
                'deleted' => 0,
                'travelSynced' => false,
                'remoteTimestamp' => null,
            ];
        }

        $io->text($this->formatInfoLine(sprintf('[%s] Remote', $datasetName), $remoteInfo, $output));

        $localInfo = $this->syncManager->readLocalInfo($target->destination);
        if (null !== $localInfo) {
            $io->text($this->formatInfoLine(sprintf('[%s] Local', $datasetName), $localInfo, $output));
        } else {
            $io->text(sprintf('[%s] Local:  no data', $datasetName));
        }

        $needsSync = $force || null === $localInfo || $remoteInfo->isNewerThan($localInfo);
        if (false === $needsSync) {
            $io->text(sprintf('[%s] Local data is up to date, no sync required', $datasetName));
            $this->logger->info('XML sync skipped: local data is up to date', [
                'dataset' => $datasetName,
            ]);

            return [
                'dataset' => $datasetName,
                'synced' => false,
                'failed' => false,
                'updated' => 0,
                'deleted' => 0,
                'travelSynced' => false,
                'remoteTimestamp' => null,
            ];
        }

        if ($dryRun) {
            $io->note(sprintf('[%s] Sync required (dry-run mode, no files downloaded)', $datasetName));

            return [
                'dataset' => $datasetName,
                'synced' => false,
                'failed' => false,
                'updated' => 0,
                'deleted' => 0,
                'travelSynced' => false,
                'remoteTimestamp' => null,
            ];
        }

        $io->section(sprintf('Syncing %s files', $datasetName));

        $progressStarted = false;
        try {
            $syncResult = $this->syncManager->syncFiles(
                $target->source,
                $target->destination,
                function (int $total) use ($io, &$progressStarted): void {
                    $progressStarted = true;
                    $io->progressStart($total);
                },
                fn () => $io->progressAdvance(),
            );
        } catch (FilesystemException $e) {
            $io->error(sprintf('[%s] Sync failed: %s', $datasetName, $e->getMessage()));
            $this->logger->error('XML sync failed during file transfer', [
                'dataset' => $datasetName,
                'exception' => $e,
            ]);

            return [
                'dataset' => $datasetName,
                'synced' => false,
                'failed' => true,
                'updated' => 0,
                'deleted' => 0,
                'travelSynced' => false,
                'remoteTimestamp' => null,
            ];
        } finally {
            if ($progressStarted) {
                $io->progressFinish();
            }
        }

        if ('travel' === $datasetName) {
            $travelSynced = true;
            $remoteTimestamp = $remoteInfo->lastTransfer->format('c');
        } else {
            $travelSynced = false;
            $remoteTimestamp = null;
        }

        $io->text(sprintf(
            '[%s] Synced %d files, deleted %d',
            $datasetName,
            $syncResult['updated'],
            $syncResult['deleted']
        ));
        $this->logger->info('XML sync completed', [
            'dataset' => $datasetName,
            'files_updated' => $syncResult['updated'],
            'files_deleted' => $syncResult['deleted'],
            'remote_timestamp' => $remoteInfo->lastTransfer->format('c'),
        ]);

        return [
            'dataset' => $datasetName,
            'synced' => true,
            'failed' => false,
            'updated' => $syncResult['updated'],
            'deleted' => $syncResult['deleted'],
            'travelSynced' => $travelSynced,
            'remoteTimestamp' => $remoteTimestamp,
        ];
    }

    private function refreshSnapshots(SymfonyStyle $io): ?BpnXmlSnapshotRefreshResult
    {
        $plan = $this->snapshotRefreshManager->buildPlan();
        if (null === $plan) {
            return null;
        }

        $progressStarted = false;
        try {
            $io->progressStart($plan->total);
            $progressStarted = true;

            return $this->snapshotRefreshManager->refresh(
                $plan,
                fn () => $io->progressAdvance(),
            );
        } finally {
            if ($progressStarted) {
                $io->progressFinish();
            }
        }
    }

    private function formatInfoLine(string $label, XmlExportInfo $info, OutputInterface $output): string
    {
        if ($output->isVerbose()) {
            return sprintf(
                '%s: %s (%d files)',
                $label,
                $info->lastTransfer->format('d.m.Y H:i:s'),
                $info->fileCount
            );
        }

        return sprintf('%s: %d files', $label, $info->fileCount);
    }
}