ractive/src/viewmodel/prototype/applyChanges/notifyPatternObservers.js

Next-generation DOM manipulation

import getPotentialWildcardMatches from 'viewmodel/prototype/applyChanges/getPotentialWildcardMatches';

var lastKey = /[^\.]+$/;

export default notifyPatternObservers;

function notifyPatternObservers ( viewmodel, keypath, onlyDirect ) {
	var potentialWildcardMatches;

	updateMatchingPatternObservers( viewmodel, keypath );

	if ( onlyDirect ) {
		return;
	}

	potentialWildcardMatches = getPotentialWildcardMatches( keypath );
	potentialWildcardMatches.forEach( upstreamPattern => {
		cascade( viewmodel, upstreamPattern, keypath );
	});
}


function cascade ( viewmodel, upstreamPattern, keypath ) {
	var group, map, actualChildKeypath;

	group = viewmodel.depsMap.patternObservers;
	map = group[ upstreamPattern ];

	if ( map ) {
		map.forEach( childKeypath => {
			var key = lastKey.exec( childKeypath )[0]; // 'baz'
			actualChildKeypath = keypath ? keypath + '.' + key : key; // 'foo.bar.baz'

			updateMatchingPatternObservers( viewmodel, actualChildKeypath );

			cascade( viewmodel, childKeypath, actualChildKeypath );
		});
	}
}

function updateMatchingPatternObservers ( viewmodel, keypath ) {
	viewmodel.patternObservers.forEach( observer => {
		if ( observer.regex.test( keypath ) ) {
			observer.update( keypath );
		}
	});
}