import { isFn } from '@formily/shared';
import React, { Fragment } from 'react';

type ReactRenderPropsChildren<T = any> = React.ReactNode | ((props: T) => React.ReactElement);

interface IPasswordStrengthProps {
  value?: any;
  children?: ReactRenderPropsChildren<number>;
}

const isNum = function (c) {
  return c >= 48 && c <= 57;
};
const isLower = function (c) {
  return c >= 97 && c <= 122;
};
const isUpper = function (c) {
  return c >= 65 && c <= 90;
};
const isSymbol = function (c) {
  return !(isLower(c) || isUpper(c) || isNum(c));
};
const isLetter = function (c) {
  return isLower(c) || isUpper(c);
};

const getStrength = (val) => {
  if (!val) return 0;
  let num = 0;
  let lower = 0;
  let upper = 0;
  let symbol = 0;
  let MNS = 0;
  let rep = 0;
  let repC = 0;
  let consecutive = 0;
  let sequential = 0;
  const len = () => num + lower + upper + symbol;
  const callMe = () => {
    let re = num > 0 ? 1 : 0;
    re += lower > 0 ? 1 : 0;
    re += upper > 0 ? 1 : 0;
    re += symbol > 0 ? 1 : 0;
    if (re > 2 && len() >= 8) {
      return re + 1;
    } else {
      return 0;
    }
  };
  for (let i = 0; i < val.length; i++) {
    const c = val.charCodeAt(i);
    if (isNum(c)) {
      num++;
      if (i !== 0 && i !== val.length - 1) {
        MNS++;
      }
      if (i > 0 && isNum(val.charCodeAt(i - 1))) {
        consecutive++;
      }
    } else if (isLower(c)) {
      lower++;
      if (i > 0 && isLower(val.charCodeAt(i - 1))) {
        consecutive++;
      }
    } else if (isUpper(c)) {
      upper++;
      if (i > 0 && isUpper(val.charCodeAt(i - 1))) {
        consecutive++;
      }
    } else {
      symbol++;
      if (i !== 0 && i !== val.length - 1) {
        MNS++;
      }
    }
    let exists = false;
    for (let j = 0; j < val.length; j++) {
      if (val[i] === val[j] && i !== j) {
        exists = true;
        repC += Math.abs(val.length / (j - i));
      }
    }
    if (exists) {
      rep++;
      const unique = val.length - rep;
      repC = unique ? Math.ceil(repC / unique) : Math.ceil(repC);
    }
    if (i > 1) {
      const last1 = val.charCodeAt(i - 1);
      const last2 = val.charCodeAt(i - 2);
      if (isLetter(c)) {
        if (isLetter(last1) && isLetter(last2)) {
          const v = val.toLowerCase();
          const vi = v.charCodeAt(i);
          const vi1 = v.charCodeAt(i - 1);
          const vi2 = v.charCodeAt(i - 2);
          if (vi - vi1 === vi1 - vi2 && Math.abs(vi - vi1) === 1) {
            sequential++;
          }
        }
      } else if (isNum(c)) {
        if (isNum(last1) && isNum(last2)) {
          if (c - last1 === last1 - last2 && Math.abs(c - last1) === 1) {
            sequential++;
          }
        }
      } else {
        if (isSymbol(last1) && isSymbol(last2)) {
          if (c - last1 === last1 - last2 && Math.abs(c - last1) === 1) {
            sequential++;
          }
        }
      }
    }
  }
  let sum = 0;
  const length = len();
  sum += 4 * length;
  if (lower > 0) {
    sum += 2 * (length - lower);
  }
  if (upper > 0) {
    sum += 2 * (length - upper);
  }
  if (num !== length) {
    sum += 4 * num;
  }
  sum += 6 * symbol;
  sum += 2 * MNS;
  sum += 2 * callMe();
  if (length === lower + upper) {
    sum -= length;
  }
  if (length === num) {
    sum -= num;
  }
  sum -= repC;
  sum -= 2 * consecutive;
  sum -= 3 * sequential;
  sum = sum < 0 ? 0 : sum;
  sum = sum > 100 ? 100 : sum;

  if (sum >= 80) {
    return 100;
  } else if (sum >= 60) {
    return 80;
  } else if (sum >= 40) {
    return 60;
  } else if (sum >= 20) {
    return 40;
  } else {
    return 20;
  }
};

export const PasswordStrength: React.FC<IPasswordStrengthProps> = (props) => {
  if (isFn(props.children)) {
    return props.children(getStrength(String(props.value || '')));
  } else {
    return <Fragment>{props.children}</Fragment>;
  }
};