linkify-content-script for chrome extensions: wraps a page phone numbers into clickable links ( uses XPATH and event delegation for performance)

content-script.js

var linkifyExtension = (function(){
    var LINKIFY_EXTENSION_CLASS = 'linkify-phone-match';
    var EXCLUDE_NODES = ['script', 'style', 'input', 'select', 'textarea', 'button', 'a', 'code', 'head', 'noscript'];
    var PHONE_MATCHERS = {
        US : {
            reg : /(^|\s)((\+1\d{10})|((\+1[ \.])?\(?\d{3}\)?[ \-\.\/]{1,3}\d{3}[ \-\.]{1,2}\d{4}))(\s|$)|(^|\s)\+(?:[0-9] ?){6,14}[0-9](\s|$)/gm,
            match : 2
        } ,
        PERMISSIVE : {
            reg : /(^|\s)(?:\+?(\d{1,3}))?([-. (]*(\d{3})[-. )]*)?((\d{3})[-. ]*(\d{2,4})(?:[-.x ]*(\d+))?)(\s|$)/gm,
            match : 0
        } 
    };
    var XPATH_TEXT_MATCHER = '//*[not('+EXCLUDE_NODES.map(function(i){ return 'ancestor-or-self::'+i; }).join(' or ')+')]/text()[normalize-space()]';
    
    //  http://james.padolsey.com/javascript/replacing-text-in-the-dom-its-not-that-simple/
    var generateLinkable = (function(){
            var uuid = 0;
            return function(nbr){
                uuid++;
                return ["<a href='javascript:void()' class='"+LINKIFY_EXTENSION_CLASS+"' id='linkify-phone-id-"+uuid+"'>"+nbr+"</a>",uuid];
            };
    })();
    
    var wrapMatch = function(textNode,nbrArr) {
        
        var temp = document.createElement('div');
        var linkables =  nbrArr.map(generateLinkable);
        var tempHTML = textNode.data;
        
        linkables.map(function(linkable,i){
            tempHTML = tempHTML.replace(nbrArr[i],linkable[0]);
        });
        
        temp.innerHTML = tempHTML;
        
        while (temp.firstChild) {
           
            textNode.parentNode.insertBefore( temp.firstChild, textNode );
        }
        
        // Remove original text-node:
        textNode.parentNode.removeChild(textNode);
       
    };
    var handleClickToCall = function(e){
       console.log('send event to bg page');
       chrome.runtime.sendMessage({e:'contentScript.request.call',data:e.target.innerText});
    };
    var mapTextNodes = function(rootEl,callback){
        var textNodes = document.evaluate(XPATH_TEXT_MATCHER, rootEl, null, XPathResult.UNORDERED_NODE_SNAPSHOT_TYPE);
        var l =  textNodes.snapshotLength;
        for(var i = 0;  i < l; i++){
            var currItem = textNodes.snapshotItem(i);
            if(typeof callback === "function")callback(currItem);
            
        };
    };
    
    return {
        lastLinkRef : false,
        isParsing:false,
        linkify : function() {
            console.time("linkify took");
            this.isParsing = true;
            console.log('linkify!');
            mapTextNodes(document,function(currItem){
               if(currItem.parentNode && currItem.parentNode.classList.contains(LINKIFY_EXTENSION_CLASS) ){
                   console.log('skip it!');
                   return;
               }
               var currText = currItem.textContent , matches = false, nbrArr = [];
               
               while(matches = PHONE_MATCHERS.PERMISSIVE.reg.exec(currText)){
                    var match  = matches[PHONE_MATCHERS.PERMISSIVE.match]; 
                         digitLength = match.replace(/\D/g, '');
                   if(digitLength.length > 6){
                       nbrArr.push( match );
                   } 
               }
               
               if(nbrArr.length && nbrArr.filter(function(i){return i;}).length){
                   console.log('FOUND :',nbrArr);
                   wrapMatch(currItem,nbrArr);
               }
                
            });
            this.isParsing = false;
            console.timeEnd("linkify took");
        },
        bindDomEvents : function(){
            var that = this;
            console.log("XPATH using : "+XPATH_TEXT_MATCHER);
            document.addEventListener('DOMNodeInserted', function(){
             
              if(!that.isParsing){
                 if(that.lastLinkRef)clearTimeout(that.lastLinkRef);
                 that.lastLinkRef = setTimeout(function(){that.linkify();},10);
              }
            });
           
           document.querySelector('body').addEventListener("click",function(e){
               if(e.target && e.target.classList && 
                    e.target.classList.contains(LINKIFY_EXTENSION_CLASS)){
                   handleClickToCall(e);
               }
           });
           
        },
    };
    
})();

setTimeout(function(){
    linkifyExtension.linkify(); 
},10);

linkifyExtension.bindDomEvents();