dgraph-javascript/graph/pathFinder.js

/**
 * Module contains utility to search graph nodes.
 *
 * You can use and change this freely as long as you keep this note.
 * @copyright: Simon Speich, 2013
 *
 * Note: Can't use dojo/dom-class since SVGElements are not supported
 * @see https://bugs.dojotoolkit.org/ticket/16309
 * @module dgraph/pathFinder
 */
import {svgCssUtil} from './svgCssUtil.js';

export let pathFinder = {

	/**
	 * Find connected target nodes using a breadth first search (BFS) search.
	 * @param {graphNode} node graph node
	 * @param {Array} nodelist list of graph nodes
	 * @param {Function} fnc callback
	 */
	searchByTargets: function(node, nodelist, fnc) {
		let openNodes = [],
			newNode, neighbors, i, len, nextNode;

		openNodes.push(node);
		while (openNodes.length > 0) {
			newNode = openNodes.shift();
			neighbors = newNode.trgNodes;
			len = neighbors.length;
			// Add each neighbor to the beginning of openNodes
			for (i = 0; i < len; i++) {
				nextNode = nodelist[neighbors[i][1]][neighbors[i][0]];
				fnc.apply(this, [nextNode]);
				openNodes.unshift(nextNode);
			}
		}
	},

	/**
	 * Find connected source nodes using a breadth first search (BFS) search.
	 * @param {graphNode} node graph node
	 * @param {Array} nodelist list of graph nodes
	 * @param {Function} fnc callback
	 */
	searchBySources: function(node, nodelist, fnc) {
		let openNodes = [],
			newNode, neighbors, i, len, nextNode;

		openNodes.push(node);
		while (openNodes.length > 0) {
			newNode = openNodes.shift();
			neighbors = newNode.srcNodes;
			len = neighbors.length;
			// Add each neighbor to the beginning of openNodes
			for (i = 0; i < len; i++) {
				nextNode = nodelist[neighbors[i][1]][neighbors[i][0]];
				fnc.apply(this, [newNode, nextNode]);
				openNodes.unshift(nextNode);
			}
		}
	},

	/**
	 * Highlight all connected edges.
	 * @param {graphNode} node graph node
	 * @param {Array} nodelist list of graph nodes
	 */
	highlightPath: function(node, nodelist) {
		let highlightSources, highlightTargets, el;

		highlightSources = function(node, srcNode) {
			var target, edge, el, z, lenZ, cl;

			lenZ = srcNode.svgEdges.length;
			for (z = 0; z < lenZ; z++) {
				target = srcNode.trgNodes[z];
				if (target[0] === node.x && target[1] === node.y) {	// order of trgNode and svgEdges is same
					edge = srcNode.svgEdges[z];
					svgCssUtil.toggle(edge, 'srcEdgeHighlighted');
					if (srcNode.svgNode) {
						el = srcNode.svgNode;
						svgCssUtil.toggle(el, 'srcNodeHighlighted');
					}
				}
			}
		};
		highlightTargets = function(node) {
			let edge, el, z, lenZ;

			lenZ = node.trgNodes.length;
			for (z = 0; z < lenZ; z++) {
				edge = node.svgEdges[z];
				svgCssUtil.toggle(edge, 'targetEdgeHighlighted');
				el = nodelist[node.trgNodes[z][1]][node.trgNodes[z][0]];
				if (el.virt === false) {
					el = el.svgNode;
					svgCssUtil.toggle(el, 'trgNodeHighlighted');
				}
			}
		};

		el = node.svgNode;  //.getElementsByTagName('circle')[0];
		svgCssUtil.toggle(el, 'nodeHighlighted');
		el = el.getElementsByTagName('circle')[0];
		el.setAttribute('r', el.getAttribute('r') === '5' ? 8: 5);
		highlightTargets(node);
		this.searchByTargets(node, nodelist, highlightTargets);
		this.searchBySources(node, nodelist, highlightSources);
	}
};