import express from 'express';
import { z } from 'zod';

const app = express();
app.use(express.json());

// Define our schema
const UserSchema = z.object({
  username: z.string().min(3).max(50),
  email: z.string().email(),
  age: z.number().min(18).optional(),
});

app.post('/users', (req, res) => {
  try {
    const validatedData = UserSchema.parse(req.body);
    // Process the validated data
    res.json({ success: true, data: validatedData });
  } catch (error) {
    res.status(400).json({ error: error.errors });
  }
});

// Nested object validation
const AddressSchema = z.object({
  street: z.string(),
  city: z.string(),
  country: z.string(),
  postalCode: z.string(),
});

const UserProfileSchema = z.object({
  personal: z.object({
    firstName: z.string(),
    lastName: z.string(),
  }),
  addresses: z.array(AddressSchema),
  preferences: z.record(z.string()),
});

// Custom validation
const PasswordSchema = z.string()
  .min(8)
  .refine(
    (password) => /[A-Z]/.test(password),
    'Password must contain at least one uppercase letter'
  )
  .refine(
    (password) => /[0-9]/.test(password),
    'Password must contain at least one number'
  );

const validateRequest = (schema: z.ZodSchema) => {
  return async (req: Request, res: Response, next: NextFunction) => {
    try {
      req.body = await schema.parseAsync(req.body);
      next();
    } catch (error) {
      res.status(400).json({
        error: {
          message: 'Validation failed',
          details: error.errors,
        },
      });
    }
  };
};

// Usage
app.post('/users', validateRequest(UserSchema), (req, res) => {
  // Your route handler logic here
});