import { Injectable, NestMiddleware } from '@nestjs/common';
import { Request, Response, NextFunction } from 'express';
import { AuditService } from '../app/auditor/services/auditor.service';
import { JwtService } from '@nestjs/jwt';
import { TokenExpiredError } from 'jsonwebtoken';
import { Audit } from '../app/auditor/schemas/audit.schema';
import { Types } from 'mongoose';
import messages from '../shared/messages/messages';

@Injectable()
export class AuditMiddleware implements NestMiddleware {
  constructor(
    private readonly auditService: AuditService,
    private readonly jwtService: JwtService,
  ) {}

  async use(req: Request, res: Response, next: NextFunction) {
    const { method, originalUrl, headers, body } = req;
    const originalSend = res.send;

    res.send = function (data, ...restArgs) {
      res.locals.data = data;
      return originalSend.apply(res, [data, ...restArgs]);
    };

    let tokenExpiredAt: Date | null = null;
    let userId: Types.ObjectId | null = null;

    if (headers.authorization) {
      const token = headers.authorization.split(' ')[1];
      try {
        const decoded = this.jwtService.verify(token, {
          secret: process.env.JWT_SECRET,
        });
        userId = new Types.ObjectId(decoded.sub);
      } catch (e) {
        if (e instanceof TokenExpiredError) {
          tokenExpiredAt = e.expiredAt;
          return res.status(401).json({
            status: 401,
            message: messages.error.token.message,
            error: messages.error.token.summary,
          });
        } else {
          return res.status(401).json({
            status: 401,
            message: messages.error.token.message,
            error: messages.error.token.summary,
          });
        }
      }
    }

    res.on('finish', async () => {
      const response = res.locals.data || {};

      // Verificar si `userId` es `null` antes de intentar registrar la auditoría
      if (userId) {
        const auditLog = {
          userId,
          method,
          url: originalUrl,
          headers,
          body,
          response:
            typeof response === 'string' ? JSON.parse(response) : response,
          tokenExpiredAt,
        } as unknown as Partial<Audit>;

        await this.auditService.log(auditLog);
      }
    });

    next();
  }
}