<?php

namespace App\Jobs;

use App\Models\BackupSchedule;
use App\Models\BackupScheduleRun;
use App\Models\BulkOperationRun;
use App\Services\BackupScheduling\PolicyTypeResolver;
use App\Services\BackupScheduling\RunErrorMapper;
use App\Services\BackupScheduling\ScheduleTimeService;
use App\Services\BulkOperationService;
use App\Services\Intune\AuditLogger;
use App\Services\Intune\BackupService;
use App\Services\Intune\PolicySyncService;
use Carbon\CarbonImmutable;
use Filament\Notifications\Events\DatabaseNotificationsSent;
use Filament\Notifications\Notification;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Foundation\Bus\Dispatchable;
use Illuminate\Queue\InteractsWithQueue;
use Illuminate\Queue\SerializesModels;
use Illuminate\Support\Arr;
use Illuminate\Support\Facades\Bus;
use Illuminate\Support\Facades\Cache;

class RunBackupScheduleJob implements ShouldQueue
{
    use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;

    public int $tries = 3;

    public function __construct(
        public int $backupScheduleRunId,
        public ?int $bulkRunId = null,
    ) {}

    public function handle(
        PolicySyncService $policySyncService,
        BackupService $backupService,
        PolicyTypeResolver $policyTypeResolver,
        ScheduleTimeService $scheduleTimeService,
        AuditLogger $auditLogger,
        RunErrorMapper $errorMapper,
        BulkOperationService $bulkOperationService,
    ): void {
        $run = BackupScheduleRun::query()
            ->with(['schedule', 'tenant', 'user'])
            ->find($this->backupScheduleRunId);

        if (! $run) {
            return;
        }

        $bulkRun = $this->bulkRunId
            ? BulkOperationRun::query()->with(['tenant', 'user'])->find($this->bulkRunId)
            : null;

        if (
            $bulkRun
            && ($bulkRun->tenant_id !== $run->tenant_id || $bulkRun->user_id !== $run->user_id)
        ) {
            $bulkRun = null;
        }

        if ($bulkRun && $bulkRun->status === 'pending') {
            $bulkOperationService->start($bulkRun);
        }

        $schedule = $run->schedule;

        if (! $schedule instanceof BackupSchedule) {
            $run->update([
                'status' => BackupScheduleRun::STATUS_FAILED,
                'error_code' => RunErrorMapper::ERROR_UNKNOWN,
                'error_message' => 'Schedule not found.',
                'finished_at' => CarbonImmutable::now('UTC'),
            ]);

            return;
        }

        $tenant = $run->tenant;

        if (! $tenant) {
            $run->update([
                'status' => BackupScheduleRun::STATUS_FAILED,
                'error_code' => RunErrorMapper::ERROR_UNKNOWN,
                'error_message' => 'Tenant not found.',
                'finished_at' => CarbonImmutable::now('UTC'),
            ]);

            return;
        }

        $lock = Cache::lock("backup_schedule:{$schedule->id}", 900);

        if (! $lock->get()) {
            $this->finishRun(
                run: $run,
                schedule: $schedule,
                status: BackupScheduleRun::STATUS_SKIPPED,
                errorCode: 'CONCURRENT_RUN',
                errorMessage: 'Another run is already in progress for this schedule.',
                summary: ['reason' => 'concurrent_run'],
                scheduleTimeService: $scheduleTimeService,
                bulkRunId: $this->bulkRunId,
            );

            return;
        }

        try {
            $nowUtc = CarbonImmutable::now('UTC');

            $run->forceFill([
                'started_at' => $run->started_at ?? $nowUtc,
                'status' => BackupScheduleRun::STATUS_RUNNING,
            ])->save();

            $this->notifyRunStarted($run, $schedule);

            $auditLogger->log(
                tenant: $tenant,
                action: 'backup_schedule.run_started',
                context: [
                    'metadata' => [
                        'backup_schedule_id' => $schedule->id,
                        'backup_schedule_run_id' => $run->id,
                        'scheduled_for' => $run->scheduled_for?->toDateTimeString(),
                    ],
                ],
                resourceType: 'backup_schedule_run',
                resourceId: (string) $run->id,
                status: 'success'
            );

            $runtime = $policyTypeResolver->resolveRuntime((array) ($schedule->policy_types ?? []));
            $validTypes = $runtime['valid'];
            $unknownTypes = $runtime['unknown'];

            if (empty($validTypes)) {
                $this->finishRun(
                    run: $run,
                    schedule: $schedule,
                    status: BackupScheduleRun::STATUS_SKIPPED,
                    errorCode: 'UNKNOWN_POLICY_TYPE',
                    errorMessage: 'All configured policy types are unknown.',
                    summary: [
                        'unknown_policy_types' => $unknownTypes,
                    ],
                    scheduleTimeService: $scheduleTimeService,
                    bulkRunId: $this->bulkRunId,
                );

                return;
            }

            $supported = array_values(array_filter(
                config('tenantpilot.supported_policy_types', []),
                fn (array $typeConfig): bool => in_array($typeConfig['type'] ?? null, $validTypes, true),
            ));

            $syncReport = $policySyncService->syncPoliciesWithReport($tenant, $supported);

            $policyIds = $syncReport['synced'] ?? [];
            $syncFailures = $syncReport['failures'] ?? [];

            $backupSet = $backupService->createBackupSet(
                tenant: $tenant,
                policyIds: $policyIds,
                actorEmail: null,
                actorName: null,
                name: 'Scheduled backup: '.$schedule->name,
                includeAssignments: false,
                includeScopeTags: false,
                includeFoundations: (bool) ($schedule->include_foundations ?? false),
            );

            $status = match ($backupSet->status) {
                'completed' => BackupScheduleRun::STATUS_SUCCESS,
                'partial' => BackupScheduleRun::STATUS_PARTIAL,
                'failed' => BackupScheduleRun::STATUS_FAILED,
                default => BackupScheduleRun::STATUS_SUCCESS,
            };

            $errorCode = null;
            $errorMessage = null;

            $summary = [
                'policies_total' => count($policyIds),
                'policies_backed_up' => (int) ($backupSet->item_count ?? 0),
                'sync_failures' => $syncFailures,
            ];

            if (! empty($unknownTypes)) {
                $status = BackupScheduleRun::STATUS_PARTIAL;
                $errorCode = 'UNKNOWN_POLICY_TYPE';
                $errorMessage = 'Some configured policy types are unknown and were skipped.';
                $summary['unknown_policy_types'] = $unknownTypes;
            }

            $this->finishRun(
                run: $run,
                schedule: $schedule,
                status: $status,
                errorCode: $errorCode,
                errorMessage: $errorMessage,
                summary: $summary,
                scheduleTimeService: $scheduleTimeService,
                backupSetId: (string) $backupSet->id,
                bulkRunId: $this->bulkRunId,
            );

            $auditLogger->log(
                tenant: $tenant,
                action: 'backup_schedule.run_finished',
                context: [
                    'metadata' => [
                        'backup_schedule_id' => $schedule->id,
                        'backup_schedule_run_id' => $run->id,
                        'status' => $status,
                        'error_code' => $errorCode,
                    ],
                ],
                resourceType: 'backup_schedule_run',
                resourceId: (string) $run->id,
                status: in_array($status, [BackupScheduleRun::STATUS_SUCCESS], true) ? 'success' : 'partial'
            );
        } catch (\Throwable $throwable) {
            $attempt = (int) method_exists($this, 'attempts') ? $this->attempts() : 1;
            $mapped = $errorMapper->map($throwable, $attempt, $this->tries);

            if ($mapped['shouldRetry']) {
                $this->release($mapped['delay']);

                return;
            }

            $this->finishRun(
                run: $run,
                schedule: $schedule,
                status: BackupScheduleRun::STATUS_FAILED,
                errorCode: $mapped['error_code'],
                errorMessage: $mapped['error_message'],
                summary: [
                    'exception' => get_class($throwable),
                    'attempt' => $attempt,
                ],
                scheduleTimeService: $scheduleTimeService,
                bulkRunId: $this->bulkRunId,
            );

            $auditLogger->log(
                tenant: $tenant,
                action: 'backup_schedule.run_failed',
                context: [
                    'metadata' => [
                        'backup_schedule_id' => $schedule->id,
                        'backup_schedule_run_id' => $run->id,
                        'error_code' => $mapped['error_code'],
                    ],
                ],
                resourceType: 'backup_schedule_run',
                resourceId: (string) $run->id,
                status: 'failed'
            );
        } finally {
            optional($lock)->release();
        }
    }

    private function notifyRunStarted(BackupScheduleRun $run, BackupSchedule $schedule): void
    {
        $user = $run->user;

        if (! $user) {
            return;
        }

        $notification = Notification::make()
            ->title('Backup started')
            ->body(sprintf('Schedule "%s" has started.', $schedule->name))
            ->info();

        $user->notifyNow($notification->toDatabase());
        DatabaseNotificationsSent::dispatch($user);
    }

    private function notifyRunFinished(BackupScheduleRun $run, BackupSchedule $schedule): void
    {
        $user = $run->user;

        if (! $user) {
            return;
        }

        $title = match ($run->status) {
            BackupScheduleRun::STATUS_SUCCESS => 'Backup completed',
            BackupScheduleRun::STATUS_PARTIAL => 'Backup completed (partial)',
            BackupScheduleRun::STATUS_SKIPPED => 'Backup skipped',
            default => 'Backup failed',
        };

        $notification = Notification::make()
            ->title($title)
            ->body(sprintf('Schedule "%s" finished with status: %s.', $schedule->name, $run->status));

        if (filled($run->error_message)) {
            $notification->body($notification->getBody()."\n".$run->error_message);
        }

        match ($run->status) {
            BackupScheduleRun::STATUS_SUCCESS => $notification->success(),
            BackupScheduleRun::STATUS_PARTIAL, BackupScheduleRun::STATUS_SKIPPED => $notification->warning(),
            default => $notification->danger(),
        };

        $user->notifyNow($notification->toDatabase());
        DatabaseNotificationsSent::dispatch($user);
    }

    private function finishRun(
        BackupScheduleRun $run,
        BackupSchedule $schedule,
        string $status,
        ?string $errorCode,
        ?string $errorMessage,
        array $summary,
        ScheduleTimeService $scheduleTimeService,
        ?string $backupSetId = null,
        ?int $bulkRunId = null,
    ): void {
        $nowUtc = CarbonImmutable::now('UTC');

        $run->forceFill([
            'status' => $status,
            'error_code' => $errorCode,
            'error_message' => $errorMessage,
            'summary' => Arr::wrap($summary),
            'finished_at' => $nowUtc,
            'backup_set_id' => $backupSetId,
        ])->save();

        $schedule->forceFill([
            'last_run_at' => $nowUtc,
            'last_run_status' => $status,
            'next_run_at' => $scheduleTimeService->nextRunFor($schedule, $nowUtc),
        ])->saveQuietly();

        $this->notifyRunFinished($run, $schedule);

        if ($bulkRunId) {
            $bulkRun = BulkOperationRun::query()->with(['tenant', 'user'])->find($bulkRunId);

            if (
                $bulkRun
                && ($bulkRun->tenant_id === $run->tenant_id)
                && ($bulkRun->user_id === $run->user_id)
                && in_array($bulkRun->status, ['pending', 'running'], true)
            ) {
                $service = app(BulkOperationService::class);

                $itemId = (string) $run->backup_schedule_id;

                match ($status) {
                    BackupScheduleRun::STATUS_SUCCESS => $service->recordSuccess($bulkRun),
                    BackupScheduleRun::STATUS_SKIPPED => $service->recordSkippedWithReason(
                        $bulkRun,
                        $itemId,
                        $errorMessage ?: 'Skipped',
                    ),
                    BackupScheduleRun::STATUS_PARTIAL => $service->recordFailure(
                        $bulkRun,
                        $itemId,
                        $errorMessage ?: 'Completed partially',
                    ),
                    default => $service->recordFailure(
                        $bulkRun,
                        $itemId,
                        $errorMessage ?: ($errorCode ?: 'Failed'),
                    ),
                };

                $bulkRun->refresh();
                if (
                    in_array($bulkRun->status, ['pending', 'running'], true)
                    && $bulkRun->processed_items >= $bulkRun->total_items
                ) {
                    $service->complete($bulkRun);
                }
            }
        }

        if ($backupSetId && in_array($status, [BackupScheduleRun::STATUS_SUCCESS, BackupScheduleRun::STATUS_PARTIAL], true)) {
            Bus::dispatch(new ApplyBackupScheduleRetentionJob($schedule->id));
        }
    }
}