import firebase from 'react-native-firebase';

import { HEADER_BACKGROUND, HEADER_TITLE, HEADER_BACK } from '../constants/colors';

export const defaultHeader = {
	headerStyle: {
		backgroundColor: HEADER_BACKGROUND
	},
	headerTitleStyle: {
		color: HEADER_TITLE
	},
	headerBackTitle: null,
	headerTintColor: HEADER_BACK
};

// gets the current screen from navigation state
export const getActiveRouteName = (navigationState) => {
	if (!navigationState) {
		return null;
	}
	const route = navigationState.routes[navigationState.index];
	// dive into nested navigators
	if (route.routes) {
		return getActiveRouteName(route);
	}
	return route.routeName;
};

export const onNavigationStateChange = (prevState, currentState) => {
	const currentScreen = getActiveRouteName(currentState);
	const prevScreen = getActiveRouteName(prevState);

	if (prevScreen !== currentScreen) {
		firebase.analytics().setCurrentScreen(currentScreen);
	}
};