3 files changed, 31 insertions, 22 deletions
diff --git a/webAO/utils/calculateApngLength.js b/webAO/utils/calculateApngLength.js
index bc6b3fa..932f581 100644
--- a/webAO/utils/calculateApngLength.js
+++ b/webAO/utils/calculateApngLength.js
@@ -1,26 +1,25 @@
-	/**
+/**
 	 * Adds up the chunk delays to find out how long a APNG is
 	 * @param {data} apngFile the APNG data
 	 */
 const calculateApngLength = (apngFile) => {
   const d = new Uint8Array(apngFile);
-			// https://wiki.mozilla.org/APNG_Specification#.60fcTL.60:_The_Frame_Control_Chunk
-			let duration = 0;
-			for (var i = 0; i < d.length; i++) {
-				// Find fcTL header (66 63 54 4C)
-				if (d[i] === 0x66
+  // https://wiki.mozilla.org/APNG_Specification#.60fcTL.60:_The_Frame_Control_Chunk
+  let duration = 0;
+  for (let i = 0; i < d.length; i++) {
+    // Find fcTL header (66 63 54 4C)
+    if (d[i] === 0x66
 					&& d[i + 1] === 0x63
 					&& d[i + 2] === 0x54
 					&& d[i + 3] === 0x4C) {
-					console.log("found apng header");
-					// numerator and denominator
-					let delay = ((d[i + 21] / d[i + 23]) * 1000)
+      // numerator and denominator
+      const delay = ((d[i + 21] / d[i + 23]) * 1000);
 
-					// minimum is 100ms
-					duration += delay < 100 ? 100 : delay;
-				}
-			}
-			console.debug(duration);
-			return duration * 10;
+      // minimum is 100ms
+      duration += delay < 100 ? 100 : delay;
+    }
+  }
+  console.debug(duration);
+  return duration * 10;
 };
 export default calculateApngLength;
diff --git a/webAO/utils/fileExists.js b/webAO/utils/fileExists.js
index 6d32a1e..7978cbc 100644
--- a/webAO/utils/fileExists.js
+++ b/webAO/utils/fileExists.js
@@ -1,8 +1,18 @@
-const fileExists = async (url) => {
+const fileExists = async (url) => new Promise((resolve, reject) => {
   const xhr = new XMLHttpRequest();
-  xhr.open('HEAD', url, false);
-  xhr.send();
-
-  return xhr.status === 200;
-};
+  xhr.open('HEAD', url);
+  xhr.onload = function (e) {
+    if (xhr.readyState === 4) {
+      if (xhr.status === 200) {
+        resolve(true);
+      } else {
+        resolve(false);
+      }
+    }
+  };
+  xhr.onerror = function (e) {
+    resolve(false);
+  };
+  xhr.send(null);
+});
 export default fileExists;
diff --git a/webAO/utils/getAnimLength.js b/webAO/utils/getAnimLength.js
index 1441548..aa303cf 100644
--- a/webAO/utils/getAnimLength.js
+++ b/webAO/utils/getAnimLength.js
@@ -1,6 +1,6 @@
 import calculatorHandler from './calculatorHandler';
 import fileExists from './fileExists.js';
-import {requestBuffer} from '../services/request.js';
+import { requestBuffer } from '../services/request.js';
 /**
 	 * Gets animation length. If the animation cannot be found, it will
 	 * silently fail and return 0 instead.