Feature(challenges): add code-uri utils

Fix(nav): points nav item propTypes

client/utils/code-uri.js

@@ -0,0 +1,64 @@
+import flow from 'lodash/flow';
+import { decodeFcc } from '../../common/utils/encode-decode';
+
+const queryRegex = /^(\?|#\?)/;
+export function legacyIsInQuery(query, decode) {
+  let decoded;
+  try {
+    decoded = decode(query);
+  } catch (err) {
+    return false;
+  }
+  if (!decoded || typeof decoded.split !== 'function') {
+    return false;
+  }
+  return decoded
+    .replace(queryRegex, '')
+    .split('&')
+    .reduce(function(found, param) {
+      var key = param.split('=')[0];
+      if (key === 'solution') {
+        return true;
+      }
+      return found;
+    }, false);
+}
+
+export function getKeyInQuery(query, keyToFind = '') {
+  return query
+    .split('&')
+    .reduce((oldValue, param) => {
+      const key = param.split('=')[0];
+      const value = param
+        .split('=')
+        .slice(1)
+        .join('=');
+
+      if (key === keyToFind) {
+        return value;
+      }
+      return oldValue;
+    }, null);
+}
+
+export function getLegacySolutionFromQuery(query = '', decode) {
+  return flow(
+    getKeyInQuery,
+    decode,
+    decodeFcc
+  )(query, 'solution');
+}
+
+export function getCodeUri({ location, decodeURIComponent }) {
+  let query;
+  if (
+    location.search &&
+    legacyIsInQuery(location.search, decodeURIComponent)
+  ) {
+    query = location.search.replace(/^\?/, '');
+  } else {
+    return null;
+  }
+
+  return getLegacySolutionFromQuery(query, decodeURIComponent);
+}