implemented reader mode

app/js/readability/src/index.js

@@ -0,0 +1,39 @@
+import { Readability, isProbablyReaderable } from '@mozilla/readability';
+import DOMPurify from 'dompurify';
+
+function isReaderable() {
+  return isProbablyReaderable(document);
+}
+
+function parseReaderable(doc) {
+  const reader = new Readability(doc);
+  const article = reader.parse();
+  return article;
+}
+
+function applyReaderable() {
+  const clonedDoc = document.cloneNode(true);
+  const article = parseReaderable(clonedDoc);
+  const markup = DOMPurify.sanitize(article.content);
+
+  // console.log('article title: ', parsed.title);
+  // console.log('HTML string of processed article content: ', parsed.content);
+  // console.log('text content of the article, with all the HTML tags removed: ', parsed.textContent);
+  // console.log('length of an article, in characters: ', parsed.length);
+  // console.log('article description, or short excerpt from the content: ', parsed.excerpt);
+  // console.log('author metadata: ', parsed.byline);
+  // console.log('content direction: ', parsed.dir);
+  // console.log('name of the site: ', parsed.siteName);
+  // console.log('content language: ', parsed.lang);
+  // console.log('published time: ', parsed.publishedTime);
+
+  if (markup) {
+    document.body.innerHTML = '<div style="margin: 4pt;">' + markup + '</div>';
+  }
+}
+
+// Attach functions to the window object
+window.isReaderable = isReaderable;
+window.applyReaderable = applyReaderable;
+
+export { isReaderable, applyReaderable };