한국 주민등록번호 파싱용 스크립트

parseNatlId.ts

const koNatlIDRegex = /^([0-9]{6})(-|)([0-9]{7})$/;

function getBirthdayFromNatlID(idNo: string): {
  year: number;
  month: number;
  date: number;
} | null {
  const formatValidityCheck = koNatlIDRegex.test(idNo);
  if (!formatValidityCheck) return null;

  const parsedResult = koNatlIDRegex.exec(idNo);
  
  const birthdayRegion = parsedResult[1];
  const identifierRegion = parsedResult[3];

  const birthdayParsed = /^([0-9]{2})([0-9]{2})([0-9]{2})$/.exec(birthdayRegion);
  if (!birthdayParsed) return null;

  const yearRegionIdentifier = identifierRegion.charAt(0);
  let yearRange = 0;

  switch (yearRegionIdentifier) {
    // backwards compatibility for 1800s
    case '9':
    case '0':
      yearRange = 1800;
      break;

    case '1':
    case '2':
    case '5':
    case '6':
      yearRange = 1900;
      break;
    
    case '3':
    case '4':
    case '7':
    case '8':
      yearRange = 2000;
      break;
  }

  if (yearRange === 0) return null;
  const year = parseInt(birthdayParsed[1], 10) + yearRange;
  const month = parseInt(birthdayParsed[2], 10);
  const date = parseInt(birthdayParsed[3], 10);

  return {
    year,
    month,
    date,
  };
}

function getRegistrationDetailsFromNatlIdNo(idNo: string): null | {
  isForeigner: boolean;
  region: {
    raw: number;
    name: 'SEOUL' | 'BUSAN' | 'INCHEON' | 'GYEONGGI' | 'GANGWON' | 'CHUNGBUK' | 'DAEJEON' | 'CHUNGNAM' | 'SEJONG' | 'JEONBUK' | 'JEONNAM' | 'GWANGJU' | 'DAEGU' | 'GYEONGBUK' | 'GYEONGNAM' | 'ULSAN' | 'JEJU';
    detail?: {
      isMetropolitan?: Boolean;
    };
  };
  office: {
    raw: number;
  };
  registerOrder: number;
} {
  const formatValidityCheck = koNatlIDRegex.test(idNo);
  if (!formatValidityCheck) return null;

  const parsedResult = koNatlIDRegex.exec(idNo);

  let isForeigner = false;
  const birthRangeId = parseInt(parsedResult[3].charAt(0));

  switch (birthRangeId) {
    case 5:
    case 6:
    case 7:
    case 8:
      isForeigner = true;
  }

  let regionName: 'SEOUL' | 'BUSAN' | 'INCHEON' | 'GYEONGGI' | 'GANGWON' | 'CHUNGBUK' | 'DAEJEON' | 'CHUNGNAM' | 'SEJONG' | 'JEONBUK' | 'JEONNAM' | 'GWANGJU' | 'DAEGU' | 'GYEONGBUK' | 'GYEONGNAM' | 'ULSAN' | 'JEJU' | undefined = undefined;
  let isMetropolitan: boolean | undefined = undefined;

  const regionCode = parseInt(parsedResult[3].slice(1, 3));

  if (0 <= regionCode && regionCode <= 8) {
    regionName = 'SEOUL';
  } else if (9 <= regionCode && regionCode <= 12) {
    regionName = 'BUSAN';
  } else if (13 <= regionCode && regionCode <= 15) {
    regionName = 'INCHEON';
  } else if (16 <= regionCode && regionCode <= 18) {
    regionName = 'GYEONGGI';
    isMetropolitan = true;
  } else if (19 <= regionCode && regionCode <= 25) {
    regionName = 'GYEONGGI';
    isMetropolitan = false;
  } else if (26 <= regionCode && regionCode <= 34) {
    regionName = 'GANGWON';
  } else if (35 <= regionCode && regionCode <= 39) {
    regionName = 'CHUNGBUK';
  } else if (regionCode === 40) {
    regionName = 'DAEJEON';
  } else if (regionCode === 44 || regionCode === 96) {
    regionName = 'SEJONG';
  } else if (41 <= regionCode && regionCode <= 47) {
    regionName = 'CHUNGNAM';
  } else if (48 <= regionCode && regionCode <= 54) {
    regionName = 'JEONBUK';
  } else if (55 <= regionCode && regionCode <= 64) {
    regionName = 'JEONNAM';
  } else if (65 <= regionCode && regionCode <= 66) {
    regionName = 'GWANGJU';
  } else if (67 <= regionCode && regionCode <= 70) {
    regionName = 'DAEGU';
  } else if (71 <= regionCode && regionCode <= 80) {
    regionName = 'GYEONGBUK';
  } else if (regionCode === 85) {
    regionName = 'ULSAN';
  } else if (81 <= regionCode && regionCode <= 90) {
    regionName = 'GYEONGNAM';
  } else if (91 <= regionCode && regionCode <= 95) {
    regionName = 'JEJU';
  } else {
    return null;
  }

  const officeCode = parseInt(parsedResult[3].slice(3, 5));
  const registerOrder = parseInt(parsedResult[3].charAt(5));

  return {
    isForeigner,
    region: {
      raw: regionCode,
      name: regionName,
      detail: isMetropolitan ? {
        isMetropolitan,
      } : undefined,
    },
    office: {
      raw: officeCode,
    },
    registerOrder,
  };
}

function validateNatlIDNo(idNo: string): boolean {
  const formatValidityCheck = koNatlIDRegex.test(idNo);
  if (!formatValidityCheck) return false;

  const parsedResult = koNatlIDRegex.exec(idNo);
  if (parsedResult === null) return false;

  const data = parsedResult[1] + parsedResult[3];
  const checkSum = parseInt(parsedResult[3].charAt(6));
  
  let checkSumCalcTempSum = 0;
  for (let i = 0; i < 8; i++) {
    const thisCharacter = data.charAt(i);
    const multiplyTarget = (i + 2);

    checkSumCalcTempSum += (parseInt(thisCharacter, 10) * multiplyTarget);
  }

  for (let offset = 0; offset < 4; offset++) {
    const thisCharacter = data.charAt(offset + 8);
    const multiplyTarget = (offset + 2);

    checkSumCalcTempSum += (parseInt(thisCharacter, 10) * multiplyTarget);
  }

  const checkSumMod = checkSumCalcTempSum % 11;
  const calculatedCheckSum = (11 - checkSumMod) % 10;

  return calculatedCheckSum === checkSum;
}

function parseNatlId(idNo: string) {
  const formatValidityCheck = koNatlIDRegex.test(idNo);
  if (!formatValidityCheck) return null;

  return {
    isValid: validateNatlIDNo(idNo),
    birthday: getBirthdayFromNatlID(idNo),
    details: getRegistrationDetailsFromNatlIdNo(idNo),
  };
}