import { BadRequestException, HttpException, HttpStatus, Logger, NotFoundException } from '@nestjs/common';
import { Prisma } from '@prisma/client';
import { createHash } from 'node:crypto';
import { BillingService } from '../billing/billing.service';
import { moneyToNumber } from '../common/money';
import type { OpenApiService } from '../open-api/open-api.service';
import { PrismaService } from '../prisma/prisma.service';
import type { GatewaySubmitResultDto, GatewaySubmitSegmentResultDto, GatewayReceiptEventDto, GatewayUplinkEventDto, GatewayPendingDeliveryQueryDto, GatewayDownstreamSentDto, GatewayDownstreamAcknowledgedDto, GatewayDownstreamFailureType, GatewayControlDeliveryResult, GatewaySubmitDeadLetterDto, RequeueGatewaySubmitExceptionDto, GatewayDownstreamRecoveryStatusDto, TimeoutUnknownDto } from './send-chain.contracts';
import { positiveInteger, normalizeReceiptStatus, normalizeCarrier, DEFAULT_DOWNSTREAM_RETRY_DELAY_MS, DEFAULT_DOWNSTREAM_RETRY_MAX_DELAY_MS, DEFAULT_DOWNSTREAM_MAX_RETRIES, DEFAULT_DOWNSTREAM_PENDING_TIMEOUT_HOURS, DEFAULT_RECEIPT_TIMEOUT_HOURS, DEFAULT_GATEWAY_SUBMIT_REQUEUE_STALE_MS, DEFAULT_DOWNSTREAM_MANUAL_REQUEUE_STALE_MS, DEFAULT_UPSTREAM_RECEIPT_INBOX_PROCESSING_STALE_MS, DEFAULT_UPSTREAM_RECEIPT_INBOX_MAX_ATTEMPTS, DEFAULT_UPSTREAM_RECEIPT_INBOX_MAX_AGE_HOURS, gatewaySubmitRequeueKey, isObjectRecord, asDateOrNull, downstreamRetryDelayMs, downstreamAckTimeoutMs, downstreamRetryBaseDelayMs, downstreamRetryMaxDelayMs, downstreamMaxRetries, downstreamPendingTimeoutHours, downstreamControlFailureMessage, normalizeSubmitStatus, downstreamDeliveryAttemptKey, hasRecoveryAuditStateChanged, normalizeRecoveryFailureCategory, aggregateReceiptSegmentState, isSameUpstreamEndpointIdentity, receiptEventKey } from './send-chain.helpers';
import type { SendSubmissionService } from './send-submission.service';
import type { SendCompletionCallbacks, SendCompletionFacade } from './send-completion.service';
import { queueFinalReceiptDeliveries } from './downstream-receipt-targets';


/**
 * R10 timeout implementation.
 * Cross-domain calls return through the stable SendChainService seam to preserve locking and test observability.
 */
export class SendTimeoutService {
  private readonly logger = new Logger('SendChainService');
  private receiptTimeoutScanRunning = false;

  constructor(
    private readonly prisma: PrismaService,
    private readonly billing: BillingService,
    private readonly openApi: OpenApiService | undefined,
    private readonly facade: SendCompletionFacade,
    private readonly callbacks: SendCompletionCallbacks,
  ) {}

  async markUnknownTimeout(data: TimeoutUnknownDto) {
    const olderThanHours = data.olderThanHours ?? positiveInteger(process.env.SMS_RECEIPT_TIMEOUT_HOURS, DEFAULT_RECEIPT_TIMEOUT_HOURS);
    const cutoff = new Date(Date.now() - olderThanHours * 60 * 60 * 1000);
    const candidates = await this.prisma.smsMessageRecord.findMany({
      where: {
        tenantId: { not: null },
        OR: [
          { status: { in: ['submitted', 'unknown'] }, submittedAt: { lte: cutoff } },
          { status: 'timeout', errorCode: 'RECEIPT_TIMEOUT', timeoutReceiptQueuedAt: null },
        ],
      },
      select: {
        id: true,
        tenantId: true,
        batchTaskId: true,
        applicationId: true,
        messageId: true,
        phoneNumber: true,
        amountCents: true,
        billingUnits: true,
        status: true,
        cmppSubmitSequenceId: true,
        cmppSubmitGroupMessageId: true,
        cmppRegisteredDelivery: true,
        timeoutAt: true,
      },
      take: 10000,
    });
    const timedOutTaskIds = new Set<string>();
    let timeout = 0;
    for (const candidate of candidates) {
      if (!candidate.tenantId) continue;
      const timedOutAt = candidate.timeoutAt ?? new Date();
      if (candidate.status !== 'timeout') {
        const transitioned = await this.prisma.smsMessageRecord.updateMany({
          where: { id: candidate.id, status: { in: ['submitted', 'unknown'] } },
          data: {
            status: 'timeout',
            receiptStatus: 'undelivered',
            receiptRawStatus: 'EXPIRED',
            errorCode: 'RECEIPT_TIMEOUT',
            errorMessage: `${olderThanHours}小时未收到明确回执，自动转超时`,
            timeoutAt: timedOutAt,
          },
        });
        if (transitioned.count !== 1) continue;
        timeout += 1;
      }
      // Refund uses the platform-message idempotency key. Re-running it for a
      // timeout whose downstream outbox was not fully queued also recovers a
      // crash between the state transition and the original refund call.
      await this.facade.refundMessage(candidate as typeof candidate & { tenantId: string }, `${olderThanHours}小时未收到明确回执，自动超时退款`);
      const queued = await queueFinalReceiptDeliveries(
        this.prisma,
        (request) => this.facade.queueAndTryDownstreamDelivery(request),
        {
          message: candidate,
          payload: {
            messageId: candidate.messageId,
            gatewayMessageId: `PLATFORM_TIMEOUT:${candidate.messageId}`,
            phoneNumber: candidate.phoneNumber,
            receiptStatus: 'undelivered',
            rawStatus: 'EXPIRED',
            errorCode: 'RECEIPT_TIMEOUT',
            errorMessage: `${olderThanHours}小时未收到明确回执，自动转超时`,
            deliveredAt: timedOutAt.toISOString(),
          },
          propagateHttpQueueError: true,
        },
      );
      if (queued.queued) {
        await this.prisma.smsMessageRecord.updateMany({
          where: { id: candidate.id, status: 'timeout', timeoutReceiptQueuedAt: null },
          data: { timeoutReceiptQueuedAt: new Date() },
        });
      }
      if (candidate.batchTaskId) timedOutTaskIds.add(candidate.batchTaskId);
    }
    for (const batchTaskId of timedOutTaskIds) {
      await this.facade.refreshTaskProgress(batchTaskId);
    }
    return { timeout };
  }

  async markExpiredDownstreamDeliveries(olderThanHours = downstreamPendingTimeoutHours()) {
    const cutoff = new Date(Date.now() - olderThanHours * 60 * 60_000);
    const expired = await this.prisma.cmppDownstreamDelivery.findMany({
      where: {
        status: 'pending',
        OR: [
          { lastRetriedAt: null, createdAt: { lte: cutoff } },
          { lastRetriedAt: { lte: cutoff } },
        ],
      },
      select: { id: true },
      take: 500,
    });
    for (const delivery of expired) {
      await this.facade.markDownstreamDeliveryFailed(
        delivery.id,
        `下游投递排队超过 ${olderThanHours} 小时，系统自动终止重试`,
        'queue_timeout',
      );
    }
    return { failed: expired.length };
  }

  async runReceiptTimeoutScan() {
    if (this.receiptTimeoutScanRunning) return;
    this.receiptTimeoutScanRunning = true;
    try {
      const [receiptResult, downstreamResult, requeueRecoveryResult, downstreamManualRecoveryResult] = await Promise.all([
        this.facade.markUnknownTimeout({}),
        this.facade.markExpiredDownstreamDeliveries(),
        this.facade.recoverStaleGatewaySubmitRequeues(),
        this.facade.recoverStaleDownstreamManualRequeues(),
      ]);
      if (receiptResult.timeout > 0) this.logger.log(`Marked ${receiptResult.timeout} messages as receipt timeout and refunded charged messages`);
      if (downstreamResult.failed > 0) this.logger.log(`Terminated ${downstreamResult.failed} expired downstream deliveries`);
      if (requeueRecoveryResult.recovered > 0) this.logger.log(`Recovered ${requeueRecoveryResult.recovered} stale Gateway submit requeues`);
      if (downstreamManualRecoveryResult.recovered > 0) this.logger.log(`Recovered ${downstreamManualRecoveryResult.recovered} stale downstream manual requeues`);
    } catch (error) {
      this.logger.error('Receipt timeout scan failed', error instanceof Error ? error.stack : String(error));
    } finally {
      this.receiptTimeoutScanRunning = false;
    }
  }
}