atom-lupa/lib/middleware/domMiddleware.js

Navigation bar and breadcrumbs

"use babel";
export default function domMiddleware() {
    return next => action => {
        if (action.type == 'goTo') {
            if (action.to) {
                let el;

                // Which type is `action.to` of? Duck typing detection.
                if (action.to.target) { // event
                    el = action.to.target.closest('.lupa-entity');
                } else if (action.to.getAttribute) { // dom element
                    el = action.to;
                }

                if (el) {
                    const loc = {start:{}, end:{}};
                    loc.start.line = ~~el.getAttribute('data-line');
                    loc.start.column = ~~el.getAttribute('data-column');
                    loc.end.line = ~~el.getAttribute('data-line-end');
                    loc.end.column = ~~el.getAttribute('data-column-end');

                    const path = el.getAttribute('data-path');
                    const newAction = Object.assign({}, action, {
                        type: 'goTo',
                        loc: loc,
                        path: path,
                    });
                    return next(newAction);
                }

                if (action.to.loc) {
                    return next(Object.assign({}, action, {
                      loc: action.to.loc
                    }));
                }

                return;
            }
        }

        next(action);
    }
}