const { body, validationResult } = require('express-validator');

/**
 * Validation middleware for user registration
 */
exports.validateRegistration = [
  body('username')
    .trim()
    .notEmpty()
    .withMessage('Username is required')
    .isLength({ min: 3, max: 50 })
    .withMessage('Username must be between 3 and 50 characters')
    .matches(/^[a-zA-Z0-9_]+$/)
    .withMessage('Username can only contain letters, numbers, and underscores'),
  
  body('email')
    .trim()
    .notEmpty()
    .withMessage('Email is required')
    .isEmail()
    .withMessage('Please provide a valid email address')
    .normalizeEmail(),
  
  body('password')
    .notEmpty()
    .withMessage('Password is required')
    .isLength({ min: 8 })
    .withMessage('Password must be at least 8 characters long')
    .matches(/^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)/)
    .withMessage('Password must contain at least one uppercase letter, one lowercase letter, and one number'),
  
  body('guestSessionId')
    .optional()
    .trim()
    .notEmpty()
    .withMessage('Guest session ID cannot be empty if provided'),
  
  // Check for validation errors
  (req, res, next) => {
    const errors = validationResult(req);
    if (!errors.isEmpty()) {
      return res.status(400).json({
        success: false,
        message: 'Validation failed',
        errors: errors.array().map(err => ({
          field: err.path,
          message: err.msg
        }))
      });
    }
    next();
  }
];

/**
 * Validation middleware for user login
 */
exports.validateLogin = [
  body('email')
    .trim()
    .notEmpty()
    .withMessage('Email is required')
    .isEmail()
    .withMessage('Please provide a valid email address')
    .normalizeEmail(),
  
  body('password')
    .notEmpty()
    .withMessage('Password is required'),
  
  // Check for validation errors
  (req, res, next) => {
    const errors = validationResult(req);
    if (!errors.isEmpty()) {
      return res.status(400).json({
        success: false,
        message: 'Validation failed',
        errors: errors.array().map(err => ({
          field: err.path,
          message: err.msg
        }))
      });
    }
    next();
  }
];