mod.ts

export interface IParams {
  password: string;
  minLen?: number;
  maxLen?: number;
  containsNum?: boolean;
  containsSpecialChar?: boolean;
  containsAlphabet?: boolean;
  checkWithCommonPasswords?: boolean;
}

export interface VerificationResult {
  isValid: boolean;
  reason?: string;
}

const url =
  "https://raw.githubusercontent.com/danielmiessler/SecLists/master/Passwords/Common-Credentials/10k-most-common.txt";
const response = await fetch(
  url,
);

const passwordList = await response.text();

export function checkPasswordWithResult({
  password,
  minLen = 0,
  maxLen = 0,
  containsNum = true,
  containsSpecialChar = true,
  containsAlphabet = true,
  checkWithCommonPasswords = false,
}: IParams): VerificationResult {
  if (minLen != 0 && password.length < minLen) {
    return {
      isValid: false,
      reason: `The password should contain at least ${minLen} characters`,
    };
  }
  if (maxLen != 0 && password.length > maxLen) {
    return {
      isValid: false,
      reason: `The password should contain at most ${maxLen} characters`,
    };
  }
  if (containsNum && password.search(/\d/) == -1) {
    return {
      isValid: false,
      reason: "The password should contain at least one digit",
    };
  }
  if (containsSpecialChar && password.search(/[^\w\s]/) == -1) {
    return {
      isValid: false,
      reason: "The password should contain at least one special character",
    };
  }
  if (containsAlphabet && password.search(/[A-Za-z]/) == -1) {
    return {
      isValid: false,
      reason: "The password should contain at least one letter",
    };
  }

  if (
    checkWithCommonPasswords && passwordList != undefined &&
    passwordList.includes(password)
  ) {
    return {
      isValid: false,
      reason: "The password should not be too common",
    };
  }

  return { isValid: true };
}

export function checkPassword(params: IParams): boolean {
  return checkPasswordWithResult(params).isValid;
}