Recursively walk through tree-structure

treeMatrix

// node { id: [Number], nodeTypeId: [String] }
// edge { fromNodeId: [Number], toNodeId: [Number], fromPort: [String] }

var decisionTree = {
    nodes: [],
    edges: [],

    getTreeMatrix: function() {
        var start = this.nodes.findBy('nodeTypeId', 'StartNode'),
            self = this;

        function getEdgesFor(node) {
            return self.edges.filterBy('fromNodeId', node.id);
        }

        function getNodeById(id) {
            return self.nodes.findBy('id', id);
        }

        function getStraightEdge(edges) {
            return (edges.length > 1) ? edges.findBy('fromPort', 'then') : edges[0];
        }

        function getNext(node) {
            var edges = getEdgesFor(node);
            if (edges.length) {
                var edge = getStraightEdge(edges);
                return getNodeById(edge.toNodeId);
            }
        }

        function hasElseNodes(node) {
            return getEdgesFor(node).length > 1;
        }

        function getNextElse(node) {
            var edge = getEdgesFor(node).findBy('fromPort', 'else');

            return getNodeById(edge.toNodeId);
        }

        function getTreeFrom(node) {
            if (!node) { return []; }

            if (hasElseNodes(node)) {
                node.elseNodes = getTreeFrom(getNextElse(node));
            }

            return [node].concat(getTreeFrom(getNext(node)));
        }


        return getTreeFrom(start);
    }
};