addressParser.js

const rawAddress = '1234 Main boulevard Ste 65-b San Francisco CA 94105';

function addressParser(address) {
  const splitAddress = address.split(" ");
  const result = {
    'Address Line 1': '',
    'Address Line 2': '',
    'City': '',
    'State': '',
    'Zip Code': '',
  };

  const streetSuffixIndex = [
    'street', 'st', 'str', 'st.',
    'road', 'rd', 'rd.',
    'way',
    'avenue', 'ave', 'ave.',
    'boulevard', 'blvd', 'blvd.',
    'lane', 'ln', 'ln.',
    'drive', 'dr', 'dr.',
    'terrace', 'ter', 'ter.',
    'place', 'pl', 'pl.',
    'court', 'ct', 'ct.',
  ];

  const secondaryDesignatorIndex = [
    'apt', 'apartment', 'suite', 'ste',
  ];

  // address line 1 and address line 2
  for (let i = 0; i < splitAddress.length; i++) {
    const lowerCaseIndex = splitAddress[i].toLowerCase();
    if (streetSuffixIndex.includes(lowerCaseIndex)) {
      const primaryNumber = splitAddress[i - 2];
      const streetName = splitAddress[i - 1];
      const streetSuffix = splitAddress[i];
      const addressLine1 = primaryNumber.concat(' ', streetName).concat(' ', streetSuffix);
      result['Address Line 1'] = addressLine1;
    }
    if (secondaryDesignatorIndex.includes(lowerCaseIndex)) {
      const secondaryDesignator = splitAddress[i];
      const secondaryNumber = splitAddress[i + 1];
      const addressLine2 = secondaryDesignator.concat(' ', secondaryNumber);
      result['Address Line 2'] = addressLine2;
    }
  }

  // city 
  splitAddress.splice(0, 5);
  let city;
  if (splitAddress.length > 3) {
    city = splitAddress[0].concat(' ', splitAddress[1]);
  } else {
    city = splitAddress[0];
  }

  // state and zipcode
  const state = splitAddress[splitAddress.length - 2];
  const zipCode = splitAddress[splitAddress.length - 1];
  
  result['City'] = city;
  result['State'] = state;
  result['Zip Code'] = zipCode;

  return result;
}

console.log(addressParser(rawAddress));