telegram-management-system/marketing-agent/services/billing-service/src/middleware/validation.js

import { validationResult } from 'express-validator';
import { logger } from '../utils/logger.js';

// Validate request middleware
export const validateRequest = (validations) => {
  return async (req, res, next) => {
    // Run all validations
    await Promise.all(validations.map(validation => validation.run(req)));

    const errors = validationResult(req);
    if (errors.isEmpty()) {
      return next();
    }

    const extractedErrors = [];
    errors.array().map(err => extractedErrors.push({ 
      field: err.path,
      message: err.msg,
      value: err.value 
    }));

    logger.warn('Validation errors', { 
      path: req.path,
      errors: extractedErrors 
    });

    return res.status(400).json({
      success: false,
      error: 'Validation failed',
      errors: extractedErrors
    });
  };
};

// Custom validators
export const validators = {
  // Validate MongoDB ObjectId
  isMongoId: (value) => {
    const mongoIdRegex = /^[0-9a-fA-F]{24}$/;
    return mongoIdRegex.test(value);
  },

  // Validate currency code
  isCurrency: (value) => {
    const validCurrencies = ['USD', 'EUR', 'GBP', 'JPY', 'CAD', 'AUD', 'CNY'];
    return validCurrencies.includes(value.toUpperCase());
  },

  // Validate credit card number (basic check)
  isCreditCard: (value) => {
    const cardRegex = /^[0-9]{13,19}$/;
    return cardRegex.test(value.replace(/\s/g, ''));
  },

  // Validate phone number
  isPhoneNumber: (value) => {
    const phoneRegex = /^\+?[1-9]\d{1,14}$/;
    return phoneRegex.test(value);
  },

  // Validate date range
  isValidDateRange: (startDate, endDate) => {
    const start = new Date(startDate);
    const end = new Date(endDate);
    return start <= end;
  },

  // Validate billing cycle
  isBillingCycle: (value) => {
    const validCycles = ['monthly', 'quarterly', 'yearly'];
    return validCycles.includes(value);
  },

  // Validate plan type
  isPlanType: (value) => {
    const validPlans = ['free', 'starter', 'professional', 'enterprise', 'custom'];
    return validPlans.includes(value);
  }
};

// Sanitization helpers
export const sanitize = {
  // Clean string input
  cleanString: (value) => {
    if (typeof value !== 'string') return value;
    return value.trim().replace(/[<>]/g, '');
  },

  // Format currency amount
  formatAmount: (value) => {
    const amount = parseFloat(value);
    return Math.round(amount * 100) / 100;
  },

  // Normalize email
  normalizeEmail: (email) => {
    return email.toLowerCase().trim();
  },

  // Clean credit card number
  cleanCardNumber: (value) => {
    return value.replace(/\s/g, '').replace(/-/g, '');
  }
};