src/api/middleware/validation.middleware.ts

import { Request, Response, NextFunction } from 'express';
import { ZodSchema, ZodError } from 'zod';

interface ValidateOptions {
  body?: ZodSchema<any>;
  query?: ZodSchema<any>;
  params?: ZodSchema<any>;
}

export function Validate(schemas: ValidateOptions): MethodDecorator {
  return function (
    target: any,
    propertyKey: string | symbol,
    descriptor: PropertyDescriptor
  ) {
    const originalMethod = descriptor.value;

    descriptor.value = async function (
      req: Request,
      res: Response,
      next: NextFunction
    ) {
      try {
        if (schemas.body) {
          req.body = schemas.body.parse(req.body);
        }
        if (schemas.query) {
          req.query = schemas.query.parse(req.query);
        }
        if (schemas.params) {
          req.params = schemas.params.parse(req.params);
        }

        return await originalMethod.call(this, req, res, next);
      } catch (err: any) {
        if (err instanceof ZodError) {
          const formattedErrors = err.issues.map(issue => ({
            field: issue.path.join('.'),
            error: issue.message
          }));

          return res.error(400, 'VALIDATION_ERROR', 'Failed to validate data', formattedErrors);
        }

        return res.error(500, 'INTERNAL_SERVER_ERROR', 'An unexpected error occurred');
      }
    };

    return descriptor;
  };
}