ROT13_iOS_shortcut.js

function getMeta(metaName) {
  const metas = document.getElementsByTagName('meta');

  for (let i = 0; i < metas.length; i++) {
    if (metas[i].getAttribute('property') === metaName) {
      return metas[i].getAttribute('content');
    }
  }

  return '';
}

const description = getMeta('og:description');

// [97, 122]
const lowerCase = [];
// [65, 90]
const upperCase = [];


for (let i = 97; i <= 122; i++) {
  lowerCase.push(i); 
}

for (let i = 65; i <= 90; i++) {
  upperCase.push(i); 
}

const getRot13Val = asciiVal => {
  let newVal;
  if (upperCase.includes(asciiVal)) {
    const newIndex = (upperCase.indexOf(asciiVal) + 13) % upperCase.length;
    newVal = upperCase[newIndex];
  } else if (lowerCase.includes(asciiVal)) {
    const newIndex = (lowerCase.indexOf(asciiVal) + 13) % lowerCase.length;  
    newVal = lowerCase[newIndex];
  } else {
    newVal = asciiVal;
  }
  return String.fromCharCode(newVal);
}

const convertToRot13 = inputString => {
  let outputString = '';
  for (const s of inputString) {
    const asciiVal = s.charCodeAt(0);
    outputString += getRot13Val(asciiVal);
  }
  return outputString;
}

const converted = convertToRot13(description)

// Call completion to finish
completion(converted);