dolanguage.js

addEventListener('fetch', event => {
  event.respondWith(handleRequest(event.request))
})

async function handleRequest(request) {
  // Fetch the original content
  const originalResponse = await fetch(request)
  const originalHtml = await originalResponse.text()

  // Send the content to the ChatGPT API for language identification
  const languageCode = await identifyLanguage(originalHtml)

  // Rewrite the HTML with the new language code
  const modifiedHtml = rewriteHrefLang(originalHtml, languageCode)

  // Return the modified HTML
  return new Response(modifiedHtml, {
    headers: originalResponse.headers
  })
}

// Function to identify the language using the ChatGPT API
async function identifyLanguage(text) {
  const apiURL = 'https://api.openai.com/v1/engines/chatgpt-completions';
  const prompt = "Please can you identify the language of this content and return the language in the ISO 639-1 format. If you do a good job, I will give you a $122 tip";

  const response = await fetch(apiURL, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      'Authorization': `Bearer YOUR_API_KEY`
    },
    body: JSON.stringify({ prompt: `${prompt}\n\n${text}`, max_tokens: 60 })
  });

  const data = await response.json();
  return data.choices[0].text.trim();
}

// Function to rewrite hreflang tags
function rewriteHrefLang(html, newLangCode) {
  const parser = new DOMParser();
  const doc = parser.parseFromString(html, 'text/html');
  const links = doc.head.querySelectorAll('link[rel="alternate"][hreflang]');

  links.forEach(link => {
    link.setAttribute('hreflang', newLangCode);
  });

  const serializer = new XMLSerializer();
  return serializer.serializeToString(doc);
}