react-native-tree-multi-select/src/helpers/treeNode.helper.ts

A super-fast, customizable tree view component for React Native with multi-selection, checkboxes, and search filtering capabilities.

import type { TreeNode } from "../types/treeView.types";
import {
    getTreeViewStore,
} from "../store/treeView.store";

/**
 * Initialize the maps for tracking tree nodes and their parent-child relationships.
 *
 * This function is intended to be called once, during component initialization,
 * with the initial tree data and any preselected node IDs.
 *
 * @param initialData - An array of TreeNode objects that represent the initial tree structure.
 * @param preselectedIds - An optional array of TreeNode IDs that should be preselected.
 */
export function initializeNodeMaps<ID>(storeId: string, initialData: TreeNode<ID>[]) {
    const treeViewStore = getTreeViewStore<ID>(storeId);
    const {
        updateNodeMap,
        updateChildToParentMap
    } = treeViewStore.getState();

    const tempNodeMap: Map<ID, TreeNode<ID>> = new Map();
    const tempChildToParentMap: Map<ID, ID> = new Map();

    /**
     * Recursively processes nodes, adding them to the nodeMap and childToParentMap.
     *
     * @param nodes - An array of TreeNode objects to be processed.
     * @param parentId - The ID of the parent node, if applicable.
     */
    const processNodes = (
        nodes: TreeNode<ID>[],
        parentId: ID | null = null
    ) => {
        nodes.forEach((node) => {
            // Each node is added to the nodeMap with its ID as the key
            tempNodeMap.set(node.id, node);
            // If the node has a parent, its ID is mapped to the parent's ID in the childToParentMap
            if (parentId) tempChildToParentMap.set(node.id, parentId);
            // If the node has children, recursively process them
            if (node.children) processNodes(node.children, node.id);
        });
    };

    // Begin processing with the initial tree data
    processNodes(initialData);

    updateNodeMap(tempNodeMap);
    updateChildToParentMap(tempChildToParentMap);
}