const {
  StateUtils: NavigationStateUtils
} = NavigationExperimental

const initialState = {
  index: 0,
  key: 'root',
  routes: [{
   key: 'login',
   title: 'Login',
   component: Login
  }]
}

function navigationState (state = initialState, action) {
  switch(action.type) {

    case PUSH_ROUTE:
      if (state.routes[state.index].key === (action.route && action.route.key)) return state
    return NavigationStateUtils.push(state, action.route)

    case POP_ROUTE:
      if (state.index === 0 || state.routes.length === 1) return state
      return NavigationStateUtils.pop(state)

   default:
     return state
  }
}

handleBackAction() {
    if (this.props.navigation.index === 0) {
      return false
    }
    this.props.popRoute()
    return true
  }

  _handleNavigate(action) {
    switch (action && action.type) {
      case 'push':
        this.props.pushRoute(action.route)
        return true
      case 'back':
      case 'pop':
        return this._handleBackAction()
      default:
        return false
    }
  }

  _navigate(route){
    this.props._handleNavigate(route)
  }

  render(){
    const route = {
      type: 'push',
      route: {
        key: this.props.navKey,
        title: this.props.pageName,
        component: this.props.componentName
      }
    }

    return(
      <TouchableHighlight onPress={() => this._navigate(route)}>
        <Text style={styles}>{pr.pageName}</Text>
      </TouchableHighlight>
    )