feat(nodes): add helper functions to iterate over child nodes

src/utils/graph.ts

@@ -342,29 +342,3 @@ export function applyNodeChanges(changes: NodeChange[], nodes: Node[]): Node[] {
 export function applyEdgeChanges(changes: EdgeChange[], edges: Edge[]): Edge[] {
   return applyChanges(changes, edges) as Edge[];
 }
-
-function flat(arr: Node[], target: Node[]) {
-  arr.forEach(function (el) {
-    if (el.childNodes) {
-      flat(el.childNodes, target);
-    } else {
-      target.push(el);
-    }
-  });
-}
-
-export function flattenNodes(nodes: Node[]): Node[] {
-  const flattened: Node[] = [];
-  flat(nodes, flattened);
-  return flattened;
-
-  // return nodes.reduce<Node[]>((result, node) => {
-  //   result.push(node);
-
-  //   if (node.childNodes) {
-  //     result.push(...flattenNodes(node.childNodes));
-  //   }
-
-  //   return result;
-  // }, []);
-}

src/utils/nodes.ts

@@ -0,0 +1,121 @@
+import { Node } from '../types';
+
+function flat(arr: Node[], target: Node[]) {
+  arr.forEach(function (el) {
+    if (el.childNodes) {
+      flat(el.childNodes, target);
+    } else {
+      target.push(el);
+    }
+  });
+}
+
+const filterNodes = (condition: (node: Node) => boolean, nodes: Node[]): Node[] => {
+  let res = [];
+
+  for (let i = 0; i < nodes.length; i++) {
+    const n = nodes[i];
+
+    if (condition(n)) {
+      res.push(n);
+    }
+
+    if (n.childNodes) {
+      const matches = filterNodes(condition, n.childNodes);
+
+      for (let j = 0; j < matches.length; j++) {
+        res.push(matches[j]);
+      }
+    }
+  }
+
+  return res;
+};
+
+const mapNodes = (accessor: (node: Node) => any, nodes: Node[]): Node[] => {
+  let res = [];
+
+  for (let i = 0; i < nodes.length; i++) {
+    const n = nodes[i];
+    res.push(accessor(n));
+
+    if (n.childNodes) {
+      n.childNodes = mapNodes(accessor, n.childNodes);
+    }
+  }
+
+  return res;
+};
+
+const forEachNode = (accessor: (node: Node) => any, nodes: Node[]): void => {
+  for (let i = 0; i < nodes.length; i++) {
+    const n = nodes[i];
+    accessor(n);
+
+    if (n.childNodes) {
+      forEachNode(accessor, n.childNodes);
+    }
+  }
+};
+
+function findNode(accessor: (node: Node) => boolean, nodes: Node[]): Node | undefined {
+  let res = undefined;
+
+  for (let i = 0; i < nodes.length; i++) {
+    const n = nodes[i];
+
+    if (accessor(n)) {
+      return n;
+    }
+
+    if (n.childNodes) {
+      res = findNode(accessor, n.childNodes);
+
+      if (res) {
+        return res;
+      }
+    }
+  }
+
+  return res;
+}
+
+export interface NodeHelper {
+  filter: (accessor: (node: Node) => boolean) => Node[];
+  map: (accessor: (node: Node) => any) => Node[];
+  find: (accessor: (node: Node) => boolean) => Node | undefined;
+  forEach: (accessor: (node: Node) => void) => void;
+  flatten: () => Node[];
+}
+
+export function nodeHelper(nodes: Node[]): NodeHelper {
+  const flatten: NodeHelper['flatten'] = () => {
+    const flattened: Node[] = [];
+    flat(nodes, flattened);
+    return flattened;
+  };
+
+  const filter: NodeHelper['filter'] = (accessor) => {
+    return filterNodes(accessor, nodes);
+  };
+
+  const forEach: NodeHelper['forEach'] = (accessor) => {
+    return forEachNode(accessor, nodes);
+  };
+
+  const find: NodeHelper['find'] = (accessor) => {
+    return findNode(accessor, nodes);
+  };
+
+  const map: NodeHelper['map'] = (accessor) => {
+    return mapNodes(accessor, nodes);
+  };
+
+  return {
+    filter,
+    forEach,
+    flatten,
+    find,
+    map,
+  };
+}