// Email: tarasov.romka@gmail.com
var result = ""
var amount

chrome.runtime.onMessage.addListener(
  function(request, sender, sendResponse) {
      console.log(sender.tab ?
              "from a content script:" + sender.tab.url :
              "from the extension");

      console.log(request.number)
      amount = request.number
      chrome.runtime.sendMessage({
        action: "FBgetGroupMembers",
        source: FBPharseGroupMembers(document)
    });
    sendResponse({farewell: "Hello popup"});
});

function FindElement(selector,scope) {
  // console.log('Finding element:'+selector);
  var _xpath = document.evaluate(selector,scope,null,XPathResult.FIRST_ORDERED_NODE_TYPE,null);

  return _xpath.singleNodeValue;
}

function FindElements(selector,scope) {
  // console.log('Finding elements:'+selector);
  var _xpath = document.evaluate(selector,scope,null,XPathResult.ORDERED_NODE_SNAPSHOT_TYPE,null);

  var count = _xpath.snapshotLength;
  console.log("els="+count);
  var res = []

  for (var i = 0;  i < count;  ++i) {
    el = _xpath.snapshotItem(i);
    res.push(el);
  }

  return res;
}

function GetTextOnly(element) {
  var text = '';
  var isAdded = false;
  for (var i = 0; i < element.childNodes.length; ++i)
    if (element.childNodes[i].nodeType === 3)
      text += element.childNodes[i].textContent;
  var text = text.replace(/Joined/i, '');
  var newtext = text.replace(/Added by/i, '').split(' on ');

  var options = { year: 'numeric', month: 'long', day: 'numeric' };

  if (cutter = newtext[0].indexOf('Today') + 1) {

    var today = new Date();
    newtext[0] = newtext[0].substring(0, cutter-2);
    newtext[1] = today.toLocaleDateString("en-US",options);
  } else if (cutter = newtext[0].indexOf('Yesterday') + 1) {
    var today = new Date();
    var yesterday = new Date(today.setDate(today.getDate() - 1));
    newtext[0] = newtext[0].substring(0, cutter-2);
    newtext[1] = yesterday.toLocaleDateString("en-US",options);
  }

  var dateAdded = newtext[1];
  if (newtext[0] != text)
    isAdded = true;
  newtext = newtext[0].trim();

  return [newtext,isAdded, dateAdded];
}

function SaveToCSV(csv, filename, isMembersPage) {
  var universalBOM = "\uFEFF"; // For other UTF-8 symbols
  csv = universalBOM + csv;
  var blob = new Blob([csv], { type: 'text/csv;charset=utf-8;' });
  if (navigator.msSaveBlob) { // IE 10+
    navigator.msSaveBlob(blob, filename);
  } else {
    var link = document.createElement("a");
    if (link.download !== undefined) { // feature detection
      // Browsers that support HTML5 download attribute
      var url = URL.createObjectURL(blob);
      link.setAttribute("href", url);
      link.setAttribute("download", filename);
      link.style.visibility = 'hidden';
      document.body.appendChild(link);
      if (isMembersPage)
        link.click();
      document.body.removeChild(link);
    }
  }
}

function scroll(){
  window.scrollTo(0,document.body.scrollHeight);
  var res = setTimeout(parse, 2000)
}

function saveAndShow(res, counter, separator, isMembersPage){
  res += separator+"\nEnd of results, total members = "+counter+"\n";
  // Save CSV
  result = res;
  filename = 'data_' + Date.now();
  SaveToCSV(res, filename, isMembersPage);

  console.log("END!");
  chrome.runtime.sendMessage({
    action: "FBgetGroupMembers",
    source: result
  });
  return res
}

function parse(){
  var separator = ";";
  var res = 'Name'+separator+'Added By'+separator+'Date of joining'+separator+'\n';
  var counter = 0;
  console.log('Start');

  var isMembersPage = true;

  // var scroller_el = FindElement("//div[contains(@class, 'uiMorePager')]/div/a", document);
  // <div class="profileBrowserGrid expandedList fbProfileBrowserNoMoreItems">

  var cont_el = FindElement("(//div[contains(@class,'fbProfileBrowserList') and contains(@class,'fbProfileBrowserListContainer')])[last()]", document);
  if (cont_el) {
    console.log(cont_el);
    var table_list = FindElements(".//ul", cont_el);
    console.log("TablesCount="+table_list.length);

    for (var i = 0, ilen = table_list.length; i < ilen; i++) {
      var table_el = table_list[i];
      if (table_el) {
        var trs_list = FindElements(".//div[contains(@data-name,'GroupProfileGridItem')]", table_el);
        // console.log(trs_list)
        console.log("Table="+i);
        for (var y = 0, ylen = trs_list.length; y < ylen; y++) {
          var el = trs_list[y];
          // console.log(el)

          if (el.innerHTML === "")
            break; // Skip empty element

          counter += 1;
          var profile_el = FindElement(".//div[contains(@class,'uiProfileBlockContent')]", el);
          // console.log(profile_el);

          // FIND NAME
          var name = FindElement(".//div/div[2]/div/a", profile_el).text;
          console.log(name)
          res += name+separator;
          // console.log("NAME="+name);

          // FIND ADDED BY
          var added_by_el_tmp = FindElement(".//div/div[2]", profile_el);
          // console.log(added_by_el_tmp)
          var addedInfEl = FindElement(".//div/div[2]/div[2]", profile_el)
          // console.log(addedInfEl)
					var added_by_el_count = added_by_el_tmp.childElementCount;
					if (added_by_el_count === 3) {
            // var added_by_el = FindElement(".//div[2]/div", added_by_el_tmp);
            var added_by_el = FindElement(".//div[2]", added_by_el_tmp); // FIXED
            console.log(added_by_el)
					} else {
            console.log(added_by_el_count)
            var added_by_el = FindElement(".//div[3]", added_by_el_tmp);
            console.log("error break")
          }

          // added_by_el = added_by_el_tmp // error string
				  // 	console.log(added_by_el);
          var added_by = GetTextOnly(added_by_el);
          if (added_by[1])
            res += added_by[0]+separator;
          else
            res += "Unknown"+separator;
          // console.log(added_by_el);

          // FIND ADDED DATE
          // added_date = FindElement(".//div[2]/div[1]/div[2]/abbr", profile_el).title;
          added_date = added_by[2];
          res += added_date+separator+"\n";
          // console.log("DATE="+added_date);
          if (counter === amount){
            return saveAndShow(res, counter, separator, isMembersPage)

          }
        }
      }
    }
    if (counter < amount){
      res = "";
      setTimeout(scroll, 2000);
    }
    else{
      return saveAndShow(res, counter, separator, isMembersPage)
    }
  }
  else {
    res = "This is not Facebook Group Members page("
    isMembersPage = false;
    return res;
  }

  // return res;
}

function FBPharseGroupMembers(document_root) {
  var res = setTimeout(parse, 2000);
  res = "Parsing..."
  console.log(res)

   console.log("END!");
   return res;
  // var separator = ";";
  // var res = 'Name'+separator+'Added By'+separator+'Date of joining'+separator+'\n';
  // var counter = 0;
  // console.log('Start');

  // var isMembersPage = true;

  // // var scroller_el = FindElement("//div[contains(@class, 'uiMorePager')]/div/a", document);
  // // <div class="profileBrowserGrid expandedList fbProfileBrowserNoMoreItems">

  // var cont_el = FindElement("(//div[contains(@class,'fbProfileBrowserList') and contains(@class,'fbProfileBrowserListContainer')])[last()]", document);
  // if (cont_el) {
  //   console.log(cont_el);
  //   var table_list = FindElements(".//ul", cont_el);
  //   console.log("TablesCount="+table_list.length);

  //   for (var i = 0, ilen = table_list.length; i < ilen; i++) {
  //     var table_el = table_list[i];
  //     if (table_el) {
  //       var trs_list = FindElements(".//div[contains(@data-name,'GroupProfileGridItem')]", table_el);
  //       // console.log(trs_list)
  //       console.log("Table="+i);
  //       for (var y = 0, ylen = trs_list.length; y < ylen; y++) {
  //         var el = trs_list[y];
  //         // console.log(el)

  //         if (el.innerHTML === "")
  //           break; // Skip empty element

  //         counter += 1;
  //         var profile_el = FindElement(".//div[contains(@class,'uiProfileBlockContent')]", el);
  //         // console.log(profile_el);

  //         // FIND NAME
  //         var name = FindElement(".//div/div[2]/div/a", profile_el).text;
  //         console.log(name)
  //         res += name+separator;
  //         // console.log("NAME="+name);

  //         // FIND ADDED BY
  //         var added_by_el_tmp = FindElement(".//div/div[2]", profile_el);
  //         // console.log(added_by_el_tmp)
  //         var addedInfEl = FindElement(".//div/div[2]/div[2]", profile_el)
  //         // console.log(addedInfEl)
	// 				var added_by_el_count = added_by_el_tmp.childElementCount;
	// 				if (added_by_el_count === 3) {
  //           // var added_by_el = FindElement(".//div[2]/div", added_by_el_tmp);
  //           var added_by_el = FindElement(".//div[2]", added_by_el_tmp); // FIXED
  //           console.log(added_by_el)
	// 				} else {
  //           console.log(added_by_el_count)
  //           var added_by_el = FindElement(".//div[3]", added_by_el_tmp);
  //           console.log("error break")
  //         }

  //         // added_by_el = added_by_el_tmp // error string
	// 			  // 	console.log(added_by_el);
  //         var added_by = GetTextOnly(added_by_el);
  //         if (added_by[1])
  //           res += added_by[0]+separator;
  //         else
  //           res += "Unknown"+separator;
  //         // console.log(added_by_el);

  //         // FIND ADDED DATE
  //         // added_date = FindElement(".//div[2]/div[1]/div[2]/abbr", profile_el).title;
  //         added_date = added_by[2];
  //         res += added_date+separator+"\n";
  //         // console.log("DATE="+added_date);
  //       }
  //     }
  //   }
  //   res += separator+"\nEnd of results, total members = "+counter+"\n";
  // } else {
  //   res = "This is not Facebook Group Members page("
  //   isMembersPage = false;
  // }

  // // Save CSV
  // filename = 'data_' + Date.now();
  // SaveToCSV(res, filename, isMembersPage);

  // console.log("END!");

  // return res;
}

// chrome.runtime.sendMessage({
//     action: "FBgetGroupMembers",
//     source: FBPharseGroupMembers(document)
// });