text: import { SET_VIEWPORT } from 'app/redux/actions/map';
  import createReducer from 'app/redux/reducers/create-reducer';
  
  const initialState = {
    viewport: {
      longitude: 0,
      latitude: 0,
      zoom: 0,
      minZoom: 0,
      maxZoom: 20,
    },
  };
  
  const setViewportReducer = (state, action) => ({
    ...state,
    viewport: action.payload.viewport,
  });
  
  const reducerMapping = {
    [SET_VIEWPORT]: setViewportReducer,
  };
  
  export default createReducer(reducerMapping, initialState);
  