1 files changed, 49 insertions, 0 deletions
diff --git a/src/lib/Base64.js b/src/lib/Base64.js
new file mode 100644
index 0000000..e83d2a5
--- /dev/null
+++ b/src/lib/Base64.js
@@ -0,0 +1,49 @@
+
+'use strict';
+// we need this because of https://bugzilla.mozilla.org/show_bug.cgi?id=439276
+
+var Base64 = {
+
+  purify: function(input) {
+    return input.replace(/[^A-Za-z0-9\+\/=]+/g, '');
+  },
+
+  alt: function(s) {
+    // URL base64 variant, see http://en.wikipedia.org/wiki/Base64#URL_applications
+    return s.replace(/-/g, '+').replace(/_/g, '/')
+  },
+
+  decode: function (input, strict) {
+    var output = '';
+    var chr1, chr2, chr3;
+    var enc1, enc2, enc3, enc4;
+    var i = 0;
+
+    // if (/[^A-Za-z0-9\+\/\=]/.test(input)) return ""; // we don't need this, caller checks for us
+
+    const k = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
+    while (i < input.length) {
+
+        enc1 = k.indexOf(input.charAt(i++));
+        enc2 = k.indexOf(input.charAt(i++));
+        enc3 = k.indexOf(input.charAt(i++));
+        enc4 = k.indexOf(input.charAt(i++));
+
+        chr1 = (enc1 << 2) | (enc2 >> 4);
+        chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
+        chr3 = ((enc3 & 3) << 6) | enc4;
+
+        output += String.fromCharCode(chr1);
+
+        if (enc3 != 64) {
+          output += String.fromCharCode(chr2);
+        }
+        if (enc4 != 64) {
+          output += String.fromCharCode(chr3);
+        }
+
+    }
+    return output;
+
+  }
+};