extracted api logic to service script

popup.html

@@ -11,9 +11,13 @@
         Download Data
     </button>
 
-    <button id="print">
-        Print Data
-    </button>
+    <p id="loading">
+
+    </p>
+
+    <p>
+        Using WaniKani Level <span id="level"></span>
+    </p>
     
     <script src="popup.js"></script>
 </body>

popup.js

@@ -1,74 +1,24 @@
-const getStorageData = key =>
-  new Promise((resolve, reject) =>
-    chrome.storage.local.get(key, result =>
-      chrome.runtime.lastError
-        ? reject(Error(chrome.runtime.lastError.message))
-        : resolve(result)
-    )
-  )
-
-const query = async (token, url) => { 
-    const requestHeaders = new Headers()
-    requestHeaders.append("Authorization", "Bearer " + token)
-
-    const endpoint = new Request(
-        url, 
-        { 
-            method: "GET", 
-            headers: requestHeaders
-        }
-    )
-
-    var result = await fetch(endpoint)
-    return result.json()
-    }
-
-const submitButton = document.getElementById("submit-token");
+const submitButton = document.getElementById("submit-token")
 const inputField = document.getElementById("token");
 
 submitButton.addEventListener( "click", () => {
     chrome.storage.local.set({"token": inputField.value})
 })
 
-const downloadButton = document.getElementById("download");
+const downloadButton = document.getElementById("download")
 downloadButton.addEventListener("click", async () => {
-    const userData = await getStorageData("token")
-    var url = "https://api.wanikani.com/v2/user"
-    var response = await query(userData.token, url)
-    var level = response.data.level
-    var levelArray = []
-    for(var i = 1; i < level; i++)
-        levelArray.push(i)
+    var loadingText = document.getElementById("loading")
+    loadingText.innerHTML = "Loading..."
 
-    var levelURLString = levelArray.join(",")
+    chrome.runtime.sendMessage("", {type: "sync"}, response => {
+            if(response.success)
+                loadingText.innerHTML = "Done!"
+            else
+                loadingText.innerHTML = response.error
+        })
+})
 
-    var url = "https://api.wanikani.com/v2/subjects?types=vocabulary&levels=" + levelURLString
-    var vocabulary = []
-
-    do
-    {
-        var response = await query(userData.token, url)
-        for(let i in response.data)
-            vocabulary.push(response.data[i].data.characters)
-
-        url = response.pages.next_url
-    } while(url !== null)
-
-    var url = "https://api.wanikani.com/v2/subjects?types=kanji&levels=" + levelURLString
-    var kanji = []
-
-    do
-    {
-        var response = await query(userData.token, url)
-        for(let i in response.data)
-        kanji.push(response.data[i].data.characters)
-
-        url = response.pages.next_url
-    } while(url !== null)
-
-    chrome.storage.local.set({
-        "vocabulary": vocabulary,
-        "kanji": kanji
-    })
-    console.log("Downloaded data!")
-})
+chrome.storage.local.get("level", (data) => {
+    const levelSpan = document.getElementById("level")
+    levelSpan.innerHTML = data.level
+})