Feature(challenges): add code-uri utils

Fix(nav): points nav item propTypes

common/utils/encode-decode.js

@@ -0,0 +1,46 @@
+import flow from 'lodash/flow';
+
+// we don't store loop protect disable key
+export function removeNoprotect(val) {
+  return val.replace(/noprotect/gi, '');
+}
+
+export function encodeScriptTags(val) {
+  return val
+    .replace(/<script>/gi, 'fccss')
+    .replace(/<\/script>/gi, 'fcces');
+}
+
+export function decodeScriptTags(val) {
+  return val
+    .replace(/fccss/gi, '<script>')
+    .replace(/fcces/gi, '</script>');
+}
+
+export function encodeFormAction(val) {
+  return val.replace(
+    // look for attributes in a form
+    /<form[^>]*>/,
+    // val is the string within the opening form tag
+    // look for an `action` attribute, replace it with a fcc tag
+    val => val.replace(/action(\s*?)=/, 'fccfaa$1=')
+  );
+}
+
+export function decodeFormAction(val) {
+  return val.replace(
+    /<form[^>]*>/,
+    val => val.replace(/fccfaa(\s*?)=/, 'action$1=')
+  );
+}
+
+export const encodeFcc = flow([
+  removeNoprotect,
+  encodeFormAction,
+  encodeScriptTags
+]);
+
+export const decodeFcc = flow([
+  decodeFormAction,
+  decodeScriptTags
+]);