add server to monorepo.

packages/server/src/collection/NestedSet/index.ts

@@ -0,0 +1,116 @@
+
+export default class NestedSet {
+  /**
+   * Constructor method.
+   * @param {Object} options -
+   */
+  constructor(items, options) {
+    this.options = {
+      parentId: 'parent_id',
+      id: 'id',
+      ...options,
+    };
+    this.items = items || [];
+    this.tree = this.linkChildren();
+  }
+
+  setItems(items) {
+    this.items = items;
+    this.tree = this.linkChildren();
+  }
+
+  /**
+   * Link nodes children.
+   */
+  linkChildren() {
+    if (this.items.length <= 0) return false;
+
+    const map = {};
+    this.items.forEach((item) => {
+      map[item.id] = item;
+      map[item.id].children = {};
+    });
+
+    this.items.forEach((item) => {
+      const parentNodeId = item[this.options.parentId];
+      if (parentNodeId) {
+        map[parentNodeId].children[item.id] = item;
+      }
+    });
+    return map;
+  }
+
+  toArray() {
+    const stack = [];
+    const treeNodes = this.items.map((i) => ({ ...i }));
+
+    const walk = (nodes) => {
+      nodes.forEach((node) => {
+        if (!node[this.options.parentId]) {
+          stack.push(node);
+        }
+        if (node.children) {
+          const childrenNodes = Object.values(node.children)
+            .map((i) => ({ ...i }));
+
+          node.children = childrenNodes;
+          walk(childrenNodes);
+        }
+      });
+    };
+    walk(treeNodes);
+    return stack;
+  }
+
+  getTree() {
+    return this.tree;
+  }
+
+  getElementById(id) {
+    return this.tree[id] || null
+  }
+
+  getParents(id) {
+    const item = this.getElementById(id);
+    const parents = [];
+    let index = 0;
+
+    const walk = (_item) => {
+      if (!item) return;
+
+      if (index) {
+        parents.push(_item);
+      }
+      if (_item[this.options.parentId]) {
+        const parentItem = this.getElementById(_item[this.options.parentId]);  
+
+        index++;
+        walk(parentItem);
+      }      
+    };
+    walk(item);
+    return parents;
+  }
+
+  toFlattenArray(nodeMapper) {
+    const flattenTree = [];
+
+    const traversal = (nodes, parentNode) => {
+      nodes.forEach((node) => {
+        let nodeMapped = node;
+
+        if (typeof nodeMapper === 'function') {
+          nodeMapped = nodeMapper(nodeMapped, parentNode);
+        }
+        flattenTree.push(nodeMapped);
+
+        if (node.children && node.children.length > 0) {
+          traversal(node.children, node);
+        }
+      });
+    };
+    traversal(this.collection);
+
+    return flattenTree;
+  }
+}