Refactor armoire content to be cached by day

website/common/script/fns/datedMemoize.js

@@ -0,0 +1,53 @@
+import moment from 'moment';
+
+function getDay (date) {
+  if (date === undefined) {
+    return 0;
+  }
+  return date instanceof moment ? date.date() : date.getDate();
+}
+
+function getMonth (date) {
+  if (date === undefined) {
+    return 0;
+  }
+  return date instanceof moment ? date.month() : date.getMonth();
+}
+
+const memoize = fn => {
+  const cache = {};
+  const cacheDate = {};
+  return (...args) => {
+    let checkedDate;
+    let identifier = '';
+    if (args.length > 0) {
+      if (typeof args[0] === 'object' && args[0].memoizeConfig) {
+        const config = args.shift();
+        checkedDate = config.date;
+        if (config.identifier) {
+          identifier = config.identifier;
+        }
+      }
+    }
+    if (!checkedDate) {
+      checkedDate = new Date();
+    }
+
+    if (cacheDate[identifier] && (getDay(checkedDate) !== getDay(cacheDate[identifier])
+      || getMonth(checkedDate) !== getMonth(cacheDate[identifier]))) {
+      // Clear cached results, since they are old
+      cache[identifier] = undefined;
+      cacheDate[identifier] = undefined;
+    }
+    if (cache[identifier]) {
+      // result is already cached
+      return cache[identifier];
+    }
+    const result = fn(...args);
+    cache[identifier] = result;
+    cacheDate[identifier] = checkedDate;
+    return result;
+  };
+};
+
+export default memoize;