[redux] move some redux utils to shared file (#1164)

* move some redux utils to shared file so they can be used in the new export view too

* enhancer is a func now

caravel/assets/javascripts/reduxUtils.js

@@ -0,0 +1,75 @@
+import shortid from 'shortid';
+import { compose } from 'redux';
+import persistState from 'redux-localstorage';
+
+export function addToObject(state, arrKey, obj) {
+  const newObject = Object.assign({}, state[arrKey]);
+  const copiedObject = Object.assign({}, obj);
+
+  if (!copiedObject.id) {
+    copiedObject.id = shortid.generate();
+  }
+  newObject[copiedObject.id] = copiedObject;
+  return Object.assign({}, state, { [arrKey]: newObject });
+}
+
+export function alterInObject(state, arrKey, obj, alterations) {
+  const newObject = Object.assign({}, state[arrKey]);
+  newObject[obj.id] = Object.assign({}, newObject[obj.id], alterations);
+  return Object.assign({}, state, { [arrKey]: newObject });
+}
+
+export function alterInArr(state, arrKey, obj, alterations) {
+  // Finds an item in an array in the state and replaces it with a
+  // new object with an altered property
+  const idKey = 'id';
+  const newArr = [];
+  state[arrKey].forEach((arrItem) => {
+    if (obj[idKey] === arrItem[idKey]) {
+      newArr.push(Object.assign({}, arrItem, alterations));
+    } else {
+      newArr.push(arrItem);
+    }
+  });
+  return Object.assign({}, state, { [arrKey]: newArr });
+}
+
+export function removeFromArr(state, arrKey, obj, idKey = 'id') {
+  const newArr = [];
+  state[arrKey].forEach((arrItem) => {
+    if (!(obj[idKey] === arrItem[idKey])) {
+      newArr.push(arrItem);
+    }
+  });
+  return Object.assign({}, state, { [arrKey]: newArr });
+}
+
+export function getFromArr(arr, id) {
+  let obj;
+  arr.forEach((o) => {
+    if (o.id === id) {
+      obj = o;
+    }
+  });
+  return obj;
+}
+
+export function addToArr(state, arrKey, obj) {
+  const newObj = Object.assign({}, obj);
+  if (!newObj.id) {
+    newObj.id = shortid.generate();
+  }
+  const newState = {};
+  newState[arrKey] = [...state[arrKey], newObj];
+  return Object.assign({}, state, newState);
+}
+
+export function enhancer() {
+  let enhancerWithPersistState = compose(persistState());
+  if (process.env.NODE_ENV === 'dev') {
+    enhancerWithPersistState = compose(
+      persistState(), window.devToolsExtension && window.devToolsExtension()
+    );
+  }
+  return enhancerWithPersistState;
+}