import { Worker, type Job } from 'bullmq';
import { createHmac } from 'node:crypto';

import type { ConnectionOptions } from 'bullmq';
import { logger } from '@/lib/logger';
import { QUEUE_CONFIGS } from '@/lib/queue';

// ─── Job Payload ─────────────────────────────────────────────────────────────

interface WebhookDeliverPayload {
  webhookId: string;
  portId: string;
  event: string;
  deliveryId: string;
  payload: Record<string, unknown>;
}

// ─── Worker ──────────────────────────────────────────────────────────────────

export const webhooksWorker = new Worker(
  'webhooks',
  async (job: Job) => {
    logger.info({ jobId: job.id, jobName: job.name }, 'Processing webhooks job');

    if (job.name !== 'deliver') {
      logger.warn({ jobName: job.name }, 'Unknown webhooks job');
      return;
    }

    const { webhookId, portId, event, deliveryId, payload } =
      job.data as WebhookDeliverPayload;

    const { db } = await import('@/lib/db');
    const { webhooks, webhookDeliveries } = await import('@/lib/db/schema/system');
    const { userProfiles } = await import('@/lib/db/schema/users');
    const { decrypt } = await import('@/lib/utils/encryption');
    const { createNotification } = await import('@/lib/services/notifications.service');
    const { eq, and } = await import('drizzle-orm');

    // 1. Fetch webhook — skip if deleted
    const webhook = await db.query.webhooks.findFirst({
      where: eq(webhooks.id, webhookId),
    });

    if (!webhook) {
      logger.info({ webhookId }, 'Webhook deleted — skipping delivery');
      await db
        .delete(webhookDeliveries)
        .where(eq(webhookDeliveries.id, deliveryId));
      return;
    }

    // 2. Decrypt secret
    let secret: string;
    try {
      secret = webhook.secret ? decrypt(webhook.secret) : '';
    } catch (err) {
      logger.error({ webhookId, err }, 'Failed to decrypt webhook secret');
      throw err; // Let BullMQ retry
    }

    // 3. Build final payload
    const finalPayload = {
      id: deliveryId,
      event,
      timestamp: new Date().toISOString(),
      port_id: portId,
      data: payload,
    };

    const bodyString = JSON.stringify(finalPayload);

    // 4. Sign with HMAC-SHA256
    const signature = secret
      ? `sha256=${createHmac('sha256', secret).update(bodyString).digest('hex')}`
      : '';

    const attempt = (job.attemptsMade ?? 0) + 1;

    // 5. POST to webhook URL with 10s timeout
    let responseStatus: number | null = null;
    let responseBody: string | null = null;
    let success = false;

    try {
      const controller = new AbortController();
      const timeoutId = setTimeout(() => controller.abort(), 10_000);

      const response = await fetch(webhook.url, {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
          'User-Agent': 'PortNimara-Webhook/1.0',
          'X-Webhook-Id': webhookId,
          'X-Webhook-Event': event,
          'X-Webhook-Signature': signature,
          'X-Webhook-Delivery': deliveryId,
        },
        body: bodyString,
        signal: controller.signal,
      });

      clearTimeout(timeoutId);
      responseStatus = response.status;
      // Read up to 1KB of response body
      const rawBody = await response.text();
      responseBody = rawBody.slice(0, 1024);
      success = response.status >= 200 && response.status < 300;
    } catch (err) {
      // Network error or timeout
      logger.warn({ webhookId, deliveryId, err }, 'Webhook delivery network error');
      responseStatus = null;
      responseBody = err instanceof Error ? err.message.slice(0, 1024) : String(err).slice(0, 1024);
      success = false;
    }

    const maxAttempts = QUEUE_CONFIGS.webhooks.maxAttempts;
    const isFinalAttempt = attempt >= maxAttempts;

    if (success) {
      // 6a. Record success
      await db
        .update(webhookDeliveries)
        .set({
          status: 'success',
          responseStatus,
          responseBody,
          attempt,
          deliveredAt: new Date(),
        })
        .where(eq(webhookDeliveries.id, deliveryId));

      logger.info({ webhookId, deliveryId, event }, 'Webhook delivered successfully');
    } else if (!success && isFinalAttempt) {
      // 6b. Final failure → dead_letter + system alert
      await db
        .update(webhookDeliveries)
        .set({
          status: 'dead_letter',
          responseStatus,
          responseBody,
          attempt,
        })
        .where(eq(webhookDeliveries.id, deliveryId));

      logger.error(
        { webhookId, deliveryId, event, attempt },
        'Webhook delivery permanently failed — dead_letter',
      );

      // Notify all super admins
      try {
        const superAdmins = await db
          .select({ userId: userProfiles.userId })
          .from(userProfiles)
          .where(and(eq(userProfiles.isSuperAdmin, true), eq(userProfiles.isActive, true)));

        for (const admin of superAdmins) {
          void createNotification({
            portId,
            userId: admin.userId,
            type: 'system_alert',
            title: 'Webhook delivery failed permanently',
            description: `Webhook "${webhook.name}" failed to deliver event "${event}" after ${maxAttempts} attempts.`,
            link: `/admin/webhooks/${webhookId}`,
            entityType: 'webhook',
            entityId: webhookId,
            dedupeKey: `webhook:dead_letter:${deliveryId}`,
            cooldownMs: 0,
          });
        }
      } catch (notifyErr) {
        logger.error({ notifyErr }, 'Failed to send dead_letter notification');
      }

      // Throw to let BullMQ mark job as failed (it won't retry since it's the final attempt)
      throw new Error(
        `Webhook delivery failed after ${attempt} attempts. Status: ${responseStatus ?? 'network error'}`,
      );
    } else {
      // 6c. Non-final failure → update record then throw to trigger retry
      await db
        .update(webhookDeliveries)
        .set({
          status: 'failed',
          responseStatus,
          responseBody,
          attempt,
        })
        .where(eq(webhookDeliveries.id, deliveryId));

      throw new Error(
        `Webhook delivery attempt ${attempt} failed. Status: ${responseStatus ?? 'network error'}. Retrying...`,
      );
    }
  },
  {
    connection: { url: process.env.REDIS_URL! } as ConnectionOptions,
    concurrency: QUEUE_CONFIGS.webhooks.concurrency,
  },
);

webhooksWorker.on('failed', (job, err) => {
  logger.error({ jobId: job?.id, jobName: job?.name, err }, 'Webhooks job failed');
});