use chrome local storage store variable to prevent empty sku array => undefined name

background.js

 'use strict';
-var index = 0;
-var skus = [];
-var noImages = "";
 
 chrome.declarativeContent.onPageChanged.removeRules(undefined, function() {
     chrome.declarativeContent.onPageChanged.addRules([{
@@ -13,53 +10,51 @@ chrome.declarativeContent.onPageChanged.removeRules(undefined, function() {
     }]);
 });
 
-chrome.extension.onMessage.addListener(function(request,sender,sendResponse){
-  if(request.idArray) {
-    // init
-    index = 0;
-    noImages = "";
+chrome.extension.onMessage.addListener(function(request,sender,sendResponse){ 
 
-    skus = request.idArray.split(',');
-    console.log(skus);
+  chrome.storage.local.get(['idArray', 'index'], function (items) {
+    let idArray = items.idArray.split(',');
+    let length = idArray.length;
+    let index = items.index;
 
-  } else if(request.nothing == "true") {
-    console.log("Message : nothing ");
-    index++;
-  } else if(request.noImage == "true") {
-    console.log("Message : noImages"); 
-    noImages += (request.currentSku + ": no results/ no valid images\n");
-    index += 2;
-  }
-  console.log("Current index : ", index);
-  console.log("Current noImages : " , noImages);
-  if(index >= skus.length) {
-    console.log("Last file was downloaded");
-    alert(noImages);
+    if(request.nothing == "true"){
+      chrome.storage.local.set({index: (index+1)});
+      index += 1;
+      console.log("Message : nothing ");
+
+    }else if(request.noImage == "true") {
+      chrome.storage.local.set({index: (index+2)});
+      index += 2;
+      console.log("Message : noImages"); 
+    }
+
+    if(index >= length) {
+      console.log("Last file was downloaded");
+      chrome.storage.local.remove(['idArray', 'index']);
+    }
+  });
 
-    index = 0;
-    noImages = "";
-    chrome.storage.local.remove('idArray');
-  }
 });
 
 chrome.downloads.onDeterminingFilename.addListener(function(item, suggest) {
 
-  // if(!skus.length){
-  //   chrome.storage.local.get('idArray', function (items) {
-  //     skus = items.idArray.split(',');
-  //   });
-  // }
   if(item.url.includes("https://digitallibrary-external.fastretailing.com/api/asset")){
-    var new_filename = skus[index] + ".zip"; 
-    suggest({filename: new_filename});
-    index++;
-    if(index >= skus.length) {
-      console.log("Last file was downloaded");
-      alert(noImages);
-
-      index = 0;
-      noImages = "";
-      chrome.storage.local.remove('idArray');
-    }
+    chrome.storage.local.get(['idArray', 'index'], function (items) {
+      let index = items.index;
+      let idArray = items.idArray.split(',');
+      let new_filename = idArray[index] + ".zip"; 
+      
+      suggest({filename: new_filename});
+      chrome.storage.local.set({index: (index+1)});
+      index += 1;
+
+      if(index >= idArray.length) {
+        console.log("Last file was downloaded");
+        chrome.storage.local.remove(['idArray', 'index']);
+      }
+
+      return true;
+    });
+    return true;
   }
 });

fetch/fetch.js

@@ -139,7 +139,7 @@
         
         // turn DOM into object array with id and file version
         let downloadlist = DOMArray.map(x => {
-            return{
+            return {
                 "id" : x.querySelector(".asset-id").innerHTML,
                 "fileVersion" :  x.querySelector(".asset-version").innerHTML
             };

popup.js

@@ -17,10 +17,10 @@ inputButton.onclick = function(element) {
     console.log("Final text = ", finalText);
     idArray = finalText.join(',');
     chrome.tabs.query({active: true, currentWindow: true}, function(tabs) {
-        chrome.storage.local.set({idArray : idArray}, function () {
+        chrome.storage.local.set({idArray : idArray, index: 0}, function () {
             console.log("set storage");
         });
-        chrome.runtime.sendMessage({idArray: idArray});
+        // chrome.runtime.sendMessage({idArray: idArray});
     }); 
 }