content.js

chrome.runtime.onMessage.addListener(function(message, sender, sendResponse){
  // get selection
  if (message.method == "get_selected_text"){
    console.log("get selected message recieved")
    var selText = window.getSelection().toString()
    sendResponse({data: selText})
    // console logger
  } else if (message.method == "console_log"){
    console.log(message.data)
    // text highlight
  } else if (message.method == "highlight_text"){
    colourText(message.text)
  }
})

function colourText(text){
  text = escapeRegExp(text)
  // match half words -- some<b>word</b>
  // very slow tech
  text = text.replace(/([^\s\\])/g, '$1(<[^\>]*?>)*')
  // console.log(text)
  // TODO: match escaped html in code
  var hay = text.replace(/\s/g, '(<[^\>]*?>|\\s)*')
  var reg = new RegExp("(" + hay + ")")  // g option matches more than one, without g only one
  // console.log(reg)
  // match and break tags (as side nesting tags is invalid)
  var bodyHtml = $(document.body).html()
  var match = bodyHtml.match(reg)
  var repl = match[0].replace(
    /(<.*?>)/g,
    "</span>" + "$1" + "<span class='anotode-highlighted-text'>"
  )
  // console.log(repl)

  $(document.body).html(
    bodyHtml.replace(
       match[0]
      ,"<span class='anotode-highlighted-text'>" + repl + "</span>"
    )
  )
}

// http://stackoverflow.com/questions/3446170/escape-string-for-use-in-javascript-regex
function escapeRegExp(str) {
  return str.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, "\\$&");
}


/*
 * FETCH DATA FROM SERVER AND HIGHLIGHT
 */
getKey("token", function(token){
  if (token == null)
    return;
  var currentUrl = window.location.href
  $.getJSON(
    "https://anotode.herokuapp.com/api/highlights?token=" + token + "&url_eq=" + encodeURIComponent(currentUrl),
    // ^^ http falls victim to cross origin restriction policy
    // http://stackoverflow.com/questions/26285539/
    // bg.js has no such restriction as it has the url in permissions
    // http://stackoverflow.com/questions/36348559/chrome
    function(data, textStatus, jqXHR){
      console.log(data)
      for (i=0; i<data.length; i++){
        if (data[i].url == currentUrl){
          try {
            colourText(data[i].text)
          } catch (er) {
            console.log('Failed')
          }
        }
      }
    }
  )

  /*
   * HIGHLIGHT Google Searches
   */
  var googleRegex = new RegExp("google[^/]+/search.q=")  // ? doesnt match in url. no idea why
  var matches = currentUrl.match(googleRegex)
  if (matches) {
    $.getJSON(
      "https://anotode.herokuapp.com/api/highlights/urls?token=" + token,
      function (data, textStatus, jqXHR) {
        $("h3.r").each(function () {
          var link = $(this).find("a").attr("href")
          if (data.indexOf(link) != -1) {
            $(this).find("a").addClass("anotode-search-highlight")
          }
        })
      }
    )
  }
})