How Does Redux Work?

redux.js

import compose from 'recompose/compose';
import EventEmitter from 'event-emitter';

const combineReducers = reducersMap => {
  const arrayOfReducers = Object.keys(reducersMap)
                          .reduce((acc, r) => [...acc, reducersMap[r]], []);
  return compose.apply(null, arrayOfReducers);
}

const dispatch = reducers => action => reducers(action);

class Store extends EventEmitter {
  constructor(reducer, initialState) {
    super(initalState);
    this.state = initalState;
    this.reducer = reducer;
  }
  dispatch = action => {
    const newState = this.reducer(action);
    this.emit('Change', newState, this.getState);
  }
  getState = () => this.state;
  onChange = fn => EventEmitter.prototype.addListener.call(this, 'Change', fn);
}

const reducers = {
  form,
  loading,
  users,
  cars
};

const createStore = reducer => initialState => {
  return new Store(reducer, initialState);
}

const store = createStore(combineReducers(reducers));

class Provider extends Component {
  constructor(props){
    this.store = props.store;
    this.context.store = this.store;
  }
  onStoreChange = () => this.setState({});
  componentWillMount() {
    this.store.addListener(this.onStoreChange);
  }
  componentWillUnMount(){
    this.store.removeListener();
  }
  render() {
    return <this.props.children />
  }
}

var connect = function(mapStateToProps, mapDispatchToProps) {
  return function (Component) {
    return class Connect extends React.Component {
      render() {
        return (<Component
          {...mapStateToProps(this.context.getState(), this.props)}
          {...mapDispatchToProps(this.context.dispatch)}
        />);
      }
    };
  }
}