openmct/platform/commonUI/browse/src/navigation/OrphanNavigationHandler.js

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 * Administration. All rights reserved.
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define([], function () {

    /**
     * Navigates away from orphan objects whenever they are detected.
     *
     * An orphan object is an object whose apparent parent does not
     * actually contain it. This may occur in certain circumstances, such
     * as when persistence succeeds for a newly-created object but fails
     * for its parent.
     *
     * @param throttle the `throttle` service
     * @param topic the `topic` service
     * @param navigationService the `navigationService`
     * @constructor
     */
    function OrphanNavigationHandler(throttle, topic, navigationService) {
        var throttledCheckNavigation;

        function getParent(domainObject) {
            var context = domainObject.getCapability('context');
            return context.getParent();
        }

        function preventOrphanNavigation(domainObject) {
            var parent = getParent(domainObject);
            parent.useCapability('composition')
                .then(function (composees) {
                    var isOrphan = composees.every(function (c) {
                        return c.getId() !== domainObject.getId();
                    });
                    if (isOrphan) {
                        parent.getCapability('action').perform('navigate');
                    }
                });
        }

        function checkNavigation() {
            var navigatedObject = navigationService.getNavigation();
            if (navigatedObject.hasCapability('context')) {
                if (!navigatedObject.getCapability('editor').isEditContextRoot()) {
                    preventOrphanNavigation(navigatedObject);
                }
            }
        }

        throttledCheckNavigation = throttle(checkNavigation);

        navigationService.addListener(throttledCheckNavigation);
        topic('mutation').listen(throttledCheckNavigation);
    }

    return OrphanNavigationHandler;
});