import React, { PureComponent } from 'react';
import { BackHandler, Animated, Easing } from 'react-native';
import { StackNavigator, addNavigationHelpers, NavigationActions } from 'react-navigation';
import { connect } from 'react-redux';
import NavigatorService from './services/navigator';
import Welcome from './routes/welcome';
import Error from './routes/error';
import Login from './routes/login';
import Main from './routes/main';

const AppNavigator = StackNavigator(
  {
    Welcome: { screen: Welcome },
    Error: { screen: Error },
    Main: { screen: Main },
    Login: { screen: Login },
  },
  {
    initialRouteName: 'Welcome',
    headerMode: 'none',
    mode: 'modal',
    navigationOptions: {
      gesturesEnabled: false,
    },
    transitionConfig: () => ({
      transitionSpec: {
        duration: 300,
        easing: Easing.out(Easing.poly(4)),
        timing: Animated.timing,
      },
      screenInterpolator: (sceneProps) => {
        const { layout, position, scene } = sceneProps;
        const { index } = scene;

        const height = layout.initHeight;
        const translateY = position.interpolate({
          inputRange: [index - 1, index, index + 1],
          outputRange: [height, 0, 0],
        });

        const opacity = position.interpolate({
          inputRange: [index - 1, index - 0.99, index],
          outputRange: [0, 1, 1],
        });

        return { opacity, transform: [{ translateY }] };
      },
    }),
  },
);

function getCurrentScreen(navigationState) {
  if (!navigationState) {
    return null;
  }
  const route = navigationState.routes[navigationState.index];
  if (route.routes) {
    return getCurrentScreen(route);
  }
  return route.routeName;
}

@connect(({ router }) => ({ router }))
class Router extends PureComponent {
  componentWillMount() {
    BackHandler.addEventListener('hardwareBackPress', this.backHandle);
  }
  componentWillUnmount() {
    BackHandler.removeEventListener('hardwareBackPress', this.backHandle);
  }

  backHandle = () => {
    const currentScreen = getCurrentScreen(this.props.router);
    if (currentScreen === 'Login' || currentScreen === 'Welcome') {
      return true;
    }
    if (currentScreen !== 'Home') {
      this.props.dispatch(NavigationActions.back());
      return true;
    }
    return false;
  };

  render() {
    const { dispatch, router } = this.props;
    const navigation = addNavigationHelpers({ dispatch, state: router });
    const navBind = (navigatorRef) => {
      NavigatorService.setContainer(navigatorRef);
    };
    return <AppNavigator navigation={navigation} ref={navBind} />;
  }
}

export function routerReducer(state, action = {}) {
  return AppNavigator.router.getStateForAction(action, state);
}

export default Router;
