"use strict";

const { validateOptions, required, isFunction, isString } = require("validatem");
const assureArray = require("assure-array");
const isIterable = require("is-iterable");

module.exports = function findInTree(options) {
	validateOptions(arguments, {
		tree: [ required ],
		predicate: [ required, isFunction ],
		childrenProperty: [ isString ],
	});

	let childrenProperty = options.childrenProperty ?? "children";
	let topLevelItems = assureArray(options.tree);
	let predicate = options.predicate;

	function find(items) {
		if (isIterable(items)) {
			for (let item of items) {
				if (predicate(item)) {
					return item;
				} else {
					let childResult = find(item[childrenProperty]);

					if (childResult !== undefined) {
						return childResult;
					}
				}
			}
		}
	}

	return find(topLevelItems);
};