From 270c64a4eeedf0343f54e3199048d5ebe1402621 Mon Sep 17 00:00:00 2001
From: Rebecca Lu <lbjrebecca@gmail.com>
Date: Thu, 7 Sep 2017 16:26:49 +0800
Subject: [PATCH] fix(base64): base64 decode/encode unicode

---
 src/getMeta.js   | 11 ++++++++++-
 src/getResult.js |  9 ++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/src/getMeta.js b/src/getMeta.js
index 1eef938..bb00318 100644
--- a/src/getMeta.js
+++ b/src/getMeta.js
@@ -10,6 +10,15 @@ function randomHexStr(length) {
   return str;
 }
 
+function b64EncodeUnicode(str) {
+  // First we use encodeURIComponent to get percent-encoded UTF-8,
+  // then we convert the percent encodings into raw bytes which
+  // can be fed into btoa.
+  return btoa(encodeURIComponent(str).replace(/%([0-9A-F]{2})/g,
+    (match, p1) => String.fromCharCode('0x' + p1)
+  ));
+}
+
 function getMeta(item, secret, appId) {
   const salt = `${Math.floor(Date.now() / 1000)}:${randomHexStr(8)}`;
   const metaObj = {
@@ -23,7 +32,7 @@ function getMeta(item, secret, appId) {
 
   const metaPrefix = JSON.stringify(metaObj);
   const hash = md5(`${appId}+${metaPrefix}+${salt}+${secret}`);
-  return btoa(`${metaPrefix};hash=${hash}`);
+  return b64EncodeUnicode(`${metaPrefix};hash=${hash}`);
 }
 
 export default getMeta;
diff --git a/src/getResult.js b/src/getResult.js
index 279d9fd..d53fd67 100644
--- a/src/getResult.js
+++ b/src/getResult.js
@@ -1,6 +1,13 @@
+function b64DecodeUnicode(str) {
+    // Going backwards: from bytestream, to percent-encoding, to original string.
+  return decodeURIComponent(atob(str).split('').map(c => {
+    return '%' + ('00' + c.charCodeAt(0).toString(16)).slice(-2);
+  }).join(''));
+}
+
 function getResult(meta) {
   try {
-    meta.result = eval('(' + atob(meta.result) + ')'); // eslint-disable-line no-eval
+    meta.result = eval('(' + b64DecodeUnicode(meta.result) + ')'); // eslint-disable-line no-eval
   } catch (e) {
   }