import type { PasswordConfig } from "../../domain/value-objects/AuthConfig";
import { isEmptyEmail, isEmptyPassword, isEmptyName } from "./validation/validationHelpers";

// Define validation types locally
export interface ValidationResult {
  isValid: boolean;
  error?: string;
}

export interface PasswordRequirements {
  hasMinLength: boolean;
}

export interface PasswordStrengthResult extends ValidationResult {
  requirements: PasswordRequirements;
}

interface ValidationConfig {
  emailRegex: RegExp;
  displayNameMinLength: number;
}

const DEFAULT_VAL_CONFIG: ValidationConfig = {
  // More robust email validation:
  // - Local part: alphanumeric, dots (not consecutive), hyphens, underscores, plus
  // - Domain: alphanumeric and hyphens
  // - TLD: at least 2 characters
  emailRegex: /^[a-zA-Z0-9]([a-zA-Z0-9._+-]*[a-zA-Z0-9])?@[a-zA-Z0-9]([a-zA-Z0-9-]*[a-zA-Z0-9])?(\.[a-zA-Z0-9]([a-zA-Z0-9-]*[a-zA-Z0-9])?)*\.[a-zA-Z]{2,}$/,
  displayNameMinLength: 2,
};

export function validateEmail(
  email: string,
  config: ValidationConfig = DEFAULT_VAL_CONFIG
): ValidationResult {
  if (isEmptyEmail(email)) return { isValid: false, error: "auth.validation.emailRequired" };
  if (!config.emailRegex.test(email.trim())) return { isValid: false, error: "auth.validation.invalidEmail" };
  return { isValid: true };
}

export function validatePasswordForLogin(password: string): ValidationResult {
  // Don't trim passwords - whitespace may be intentional
  if (isEmptyPassword(password)) return { isValid: false, error: "auth.validation.passwordRequired" };
  return { isValid: true };
}

export function validatePasswordForRegister(
  password: string,
  config: PasswordConfig,
): PasswordStrengthResult {
  // Don't trim passwords - whitespace may be intentional
  if (isEmptyPassword(password)) {
    return { isValid: false, error: "auth.validation.passwordRequired", requirements: { hasMinLength: false } };
  }

  const req: PasswordRequirements = {
    hasMinLength: password.length >= config.minLength,
  };

  if (!req.hasMinLength) return { isValid: false, error: "auth.validation.passwordTooShort", requirements: req };

  return { isValid: true, requirements: req };
}

export function validatePasswordConfirmation(password: string, confirm: string): ValidationResult {
  // Don't trim passwords - whitespace may be intentional
  if (isEmptyPassword(confirm)) return { isValid: false, error: "auth.validation.confirmPasswordRequired" };
  if (password !== confirm) return { isValid: false, error: "auth.validation.passwordsDoNotMatch" };
  return { isValid: true };
}

export function validateDisplayName(
  name: string,
  minLength: number = DEFAULT_VAL_CONFIG.displayNameMinLength
): ValidationResult {
  if (isEmptyName(name)) return { isValid: false, error: "auth.validation.nameRequired" };
  if (name.trim().length < minLength) return { isValid: false, error: "auth.validation.nameTooShort" };
  return { isValid: true };
}