<?php

namespace App\Jobs;

use App\Jobs\Middleware\TrackOperationRun;
use App\Models\BackupSchedule;
use App\Models\BackupScheduleRun;
use App\Models\OperationRun;
use App\Models\Tenant;
use App\Services\BackupScheduling\PolicyTypeResolver;
use App\Services\BackupScheduling\RunErrorMapper;
use App\Services\BackupScheduling\ScheduleTimeService;
use App\Services\Intune\AuditLogger;
use App\Services\Intune\BackupService;
use App\Services\Intune\PolicySyncService;
use App\Services\OperationRunService;
use App\Support\OperationRunLinks;
use Carbon\CarbonImmutable;
use Filament\Actions\Action;
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 ?OperationRun $operationRun = null;

    public function __construct(
        public int $backupScheduleRunId,
        ?OperationRun $operationRun = null,
    ) {
        $this->operationRun = $operationRun;
    }

    public function middleware(): array
    {
        return [new TrackOperationRun];
    }

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

        if (! $run) {
            if ($this->operationRun) {
                $this->markOperationRunFailed(
                    run: $this->operationRun,
                    summaryCounts: [],
                    reasonCode: 'run_not_found',
                    reason: 'Backup schedule run not found.',
                );
            }

            return;
        }

        $tenant = $run->tenant;

        if ($tenant instanceof Tenant) {
            $this->resolveOperationRunFromContext($tenant, $run);
        }

        if ($this->operationRun) {
            $this->operationRun->update([
                'context' => array_merge($this->operationRun->context ?? [], [
                    'backup_schedule_id' => (int) $run->backup_schedule_id,
                    'backup_schedule_run_id' => (int) $run->getKey(),
                ]),
            ]);

            /** @var OperationRunService $operationRunService */
            $operationRunService = app(OperationRunService::class);

            if ($this->operationRun->status === 'queued') {
                $operationRunService->updateRun($this->operationRun, 'running');
            }
        }

        $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'),
            ]);

            if ($this->operationRun) {
                $this->markOperationRunFailed(
                    run: $this->operationRun,
                    summaryCounts: [
                        'total' => 0,
                        'processed' => 0,
                        'failed' => 1,
                    ],
                    reasonCode: 'schedule_not_found',
                    reason: 'Schedule not found.',
                );
            }

            return;
        }

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

            if ($this->operationRun) {
                $this->markOperationRunFailed(
                    run: $this->operationRun,
                    summaryCounts: [
                        'total' => 0,
                        'processed' => 0,
                        'failed' => 1,
                    ],
                    reasonCode: 'tenant_not_found',
                    reason: 'Tenant not found.',
                );
            }

            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,
            );

            $this->syncOperationRunFromRun(
                tenant: $tenant,
                schedule: $schedule,
                run: $run->refresh(),
            );

            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,
                );

                $this->syncOperationRunFromRun(
                    tenant: $tenant,
                    schedule: $schedule,
                    run: $run->refresh(),
                );

                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,
            );

            $this->syncOperationRunFromRun(
                tenant: $tenant,
                schedule: $schedule,
                run: $run->refresh(),
            );

            $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 ($mapped['shouldRetry']) {
                if ($this->operationRun) {
                    /** @var OperationRunService $operationRunService */
                    $operationRunService = app(OperationRunService::class);
                    $operationRunService->updateRun($this->operationRun, 'running', 'pending');
                }

                $this->release($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,
            );

            $this->syncOperationRunFromRun(
                tenant: $tenant,
                schedule: $schedule,
                run: $run->refresh(),
            );

            $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.', $schedule->name))
            ->info()
            ->actions([
                Action::make('view_run')
                    ->label('View run')
                    ->url($this->operationRun ? OperationRunLinks::view($this->operationRun, $run->tenant) : OperationRunLinks::index($run->tenant)),
            ]);

        $notification->sendToDatabase($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(),
        };

        $notification
            ->actions([
                Action::make('view_run')
                    ->label('View run')
                    ->url($this->operationRun ? OperationRunLinks::view($this->operationRun, $run->tenant) : OperationRunLinks::index($run->tenant)),
            ])
            ->sendToDatabase($user);
    }

    private function syncOperationRunFromRun(
        Tenant $tenant,
        BackupSchedule $schedule,
        BackupScheduleRun $run,
    ): void {
        if (! $this->operationRun) {
            return;
        }

        $outcome = match ($run->status) {
            BackupScheduleRun::STATUS_SUCCESS => 'succeeded',
            BackupScheduleRun::STATUS_PARTIAL => 'partially_succeeded',
            // Note: 'cancelled' is a reserved OperationRun outcome token.
            // We treat schedule SKIPPED/CANCELED as terminal failures with a failure entry.
            BackupScheduleRun::STATUS_SKIPPED,
            BackupScheduleRun::STATUS_CANCELED => 'failed',
            default => 'failed',
        };

        $summary = is_array($run->summary) ? $run->summary : [];
        $syncFailures = $summary['sync_failures'] ?? [];

        $policiesTotal = (int) ($summary['policies_total'] ?? 0);
        $policiesBackedUp = (int) ($summary['policies_backed_up'] ?? 0);
        $syncFailureCount = is_array($syncFailures) ? count($syncFailures) : 0;

        $failedCount = max(0, $policiesTotal - $policiesBackedUp);

        $summaryCounts = [
            'total' => $policiesTotal,
            'processed' => $policiesTotal,
            'succeeded' => $policiesBackedUp,
            'failed' => $failedCount,
            'skipped' => 0,
            'created' => filled($run->backup_set_id) ? 1 : 0,
            'updated' => $policiesBackedUp,
            'items' => $policiesTotal,
        ];

        $failures = [];

        if (filled($run->error_message) || filled($run->error_code)) {
            $failures[] = [
                'code' => strtolower((string) ($run->error_code ?: 'backup_schedule_error')),
                'message' => (string) ($run->error_message ?: 'Backup schedule run failed.'),
            ];
        }

        if (is_array($syncFailures)) {
            foreach ($syncFailures as $failure) {
                if (! is_array($failure)) {
                    continue;
                }

                $policyType = (string) ($failure['policy_type'] ?? 'unknown');
                $status = is_numeric($failure['status'] ?? null) ? (int) $failure['status'] : null;
                $errors = $failure['errors'] ?? null;

                $firstErrorMessage = null;
                if (is_array($errors) && isset($errors[0]) && is_array($errors[0])) {
                    $firstErrorMessage = $errors[0]['message'] ?? null;
                }

                $message = $status !== null
                    ? "{$policyType}: Graph returned {$status}"
                    : "{$policyType}: Graph request failed";

                if (is_string($firstErrorMessage) && $firstErrorMessage !== '') {
                    $message .= ' - '.trim($firstErrorMessage);
                }

                $failures[] = [
                    'code' => $status !== null ? 'graph_http_'.(string) $status : 'graph_error',
                    'message' => $message,
                ];
            }
        }

        /** @var OperationRunService $operationRunService */
        $operationRunService = app(OperationRunService::class);

        $this->operationRun->update([
            'context' => array_merge($this->operationRun->context ?? [], [
                'backup_schedule_id' => (int) $schedule->getKey(),
                'backup_schedule_run_id' => (int) $run->getKey(),
                'backup_set_id' => $run->backup_set_id ? (int) $run->backup_set_id : null,
            ]),
        ]);

        $operationRunService->updateRun(
            $this->operationRun,
            status: 'completed',
            outcome: $outcome,
            summaryCounts: $summaryCounts,
            failures: $failures,
        );
    }

    private function markOperationRunFailed(
        OperationRun $run,
        array $summaryCounts,
        string $reasonCode,
        string $reason,
    ): void {
        /** @var OperationRunService $operationRunService */
        $operationRunService = app(OperationRunService::class);

        $operationRunService->updateRun(
            $run,
            status: 'completed',
            outcome: 'failed',
            summaryCounts: $summaryCounts,
            failures: [
                [
                    'code' => $reasonCode,
                    'message' => $reason,
                ],
            ],
        );
    }

    private function resolveOperationRunFromContext(Tenant $tenant, BackupScheduleRun $run): void
    {
        if ($this->operationRun) {
            return;
        }

        $operationRun = OperationRun::query()
            ->where('tenant_id', $tenant->getKey())
            ->whereIn('type', ['backup_schedule.run_now', 'backup_schedule.retry'])
            ->whereIn('status', ['queued', 'running'])
            ->where('context->backup_schedule_run_id', (int) $run->getKey())
            ->latest('id')
            ->first();

        if ($operationRun instanceof OperationRun) {
            $this->operationRun = $operationRun;
        }
    }

    private function finishRun(
        BackupScheduleRun $run,
        BackupSchedule $schedule,
        string $status,
        ?string $errorCode,
        ?string $errorMessage,
        array $summary,
        ScheduleTimeService $scheduleTimeService,
        ?string $backupSetId = 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 ($backupSetId && in_array($status, [BackupScheduleRun::STATUS_SUCCESS, BackupScheduleRun::STATUS_PARTIAL], true)) {
            Bus::dispatch(new ApplyBackupScheduleRetentionJob($schedule->id));
        }
    }
}