Simple Scripts to Modify HTML Content

highlight-selected-text.js

(function(module){
  if(window[module.name]){
    return;
  }
  module.init();
  window[module.name] = module.run;
})({
    name: "highlightSelection",
    init : function(){
      var css = document.createElement('link');
      css.rel = 'stylesheet';
      css.href= '//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/styles/default.min.css';
      document.body.appendChild(css);
      var script = document.createElement("script");
      script.src = "//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/highlight.min.js";      
      document.body.appendChild(script);      
    },
    run : function(lang){
      if(!window.hljs){
        console.log("Waiting for highlight script to load");
        return;
      }
      var selection = window.getSelection().anchorNode;
      
      if(!selection){
        return;
      }

      var target = selection.parentElement;
      if(lang){ 
        target.className += " lang-" + lang;
      }
      hljs.highlightBlock(target);
    }
});