Reducer with immutablejs

reducer-immutable.js

import { handleActions } from 'redux-actions'
import { INVOICE } from '../constants'
import { INVOICE_JSON } from '../data'
import Immutable from 'immutable'

let obj = {};

let { ADD, UPDATE, REMOVE, RECIPIENT_ADD, ITEM_REMOVE, ITEM_ADD } = INVOICE;

obj[ADD] = (state, action)=>{
  return state.push(Immutable.fromJS(action.payload));
};
obj[UPDATE] = (state, action)=>{
  let { index, selected, value } = action.payload;
  selected.unshift(index);
  return state.updateIn(selected, val => value);
};
obj[RECIPIENT_ADD] = (state, action)=>{
  let { index } = action.payload;
  return state.updateIn([index, 'to', 'recipients'], val => val.push(INVOICE_JSON.to.recipients[0]))
};
obj[ITEM_ADD] = (state, action)=>{
  let { index, selected, value } = action.payload;
  selected.unshift(index);
  return state.updateIn(selected, val => val.push(INVOICE_JSON.items[0]));
};
obj[ITEM_REMOVE] = (state, action)=>{
  let { index, selected } = action.payload;
  selected.unshift(index);
  return state.removeIn(selected);
};
obj[REMOVE] = (state, action)=>{
  return state.remove(action.payload);
}
export default handleActions(obj, Immutable.fromJS([]));