"use strict";

import {addNavigationHelpers, NavigationActions} from 'react-navigation';
import {createReactNavigationReduxMiddleware, createReduxBoundAddListener} from 'react-navigation-redux-helpers';
import {subReducer, cowValueModel as cow} from 'redux-sac';
import {connect} from 'react-redux';

const {navigate, back, reset} = NavigationActions;

export default navigationStateKey => {
    const accessNavigationState = cow(navigationStateKey);

    const createNavigationReduxConnector = name => ({
        middleware: createReactNavigationReduxMiddleware(name, accessNavigationState),
        connectNavigation: connect(
            state => ({state: accessNavigationState(state)}),
            null,
            ({state}, {dispatch}, ownProps) => ({
                navigation: addNavigationHelpers({dispatch, state, addListener: createReduxBoundAddListener(name)}),
                ...ownProps
            })
        )
    });

    const backButtonHandler = ({dispatch, getState}) => {
        if (accessNavigationState(getState()).index === 0) return false;
        dispatch(back());
        return true;
    };

    const topOfNavigationStack = state => {
        const {routes} = accessNavigationState(state);
        return routes[routes.length - 1] || {};
    };

    const createConnectedNavigatorPieces = (BareNavigator, name = "root") => {
        const {middleware, connectNavigation} = createNavigationReduxConnector(name);
        const bareReducer = (state, action) => BareNavigator.router.getStateForAction(action, state);
        return {
            Navigator: connectNavigation(BareNavigator),
            reducer: subReducer(navigationStateKey, bareReducer),
            middleware
        };
    };

    const resetRoutes = routeNames => reset({
        actions: routeNames.map(routeName => navigate({routeName})),
        index: routeNames.length - 1
    });

    const isRoute = expected => ({routeName}) => routeName === expected;

    const isTopRoute = expected => state => isRoute(expected)(topOfNavigationStack(state));

    const goBackFrom = routeName => ({dispatch, getState}) => {
        if (isTopRoute(routeName)(getState())) {
            dispatch(back());
        }
    };

    const getNavigationState = state => accessNavigationState(state);

    return {
        backButtonHandler,
        api: {
            getNavigationState,
            topOfNavigationStack,
            resetRoutes,
            isRoute,
            isTopRoute,
            goBackFrom
        },
        createConnectedNavigatorPieces
    };
};