Structured Form Validation via Regex Pattern Matching and Object Destructuring

import { reactive } from 'vue';
 
export function useFormValidator(rules) {
  const validationErrors = reactive({});
 
  function validatePayload(formData) {
    Object.keys(validationErrors).forEach(key => delete validationErrors[key]);
 
    for (const [field, { pattern, required, minLength }] of Object.entries(rules)) {
      const value = formData[field] ?? '';
      const trimmed = typeof value === 'string' ? value.trim() : '';
 
      if (required && trimmed.length === 0) {
        validationErrors[field] = 'Field is required';
        continue;
      }
      if (minLength && trimmed.length < minLength) {
        validationErrors[field] = `Must be at least ${minLength} characters`;
        continue;
      }
      if (pattern && !pattern.test(trimmed)) {
        validationErrors[field] = 'Invalid format';
      }
    }
 
    return Object.keys(validationErrors).length === 0;
  }
 
  return { validationErrors, validatePayload };
}