<?php

if (!function_exists('generate_tree')) {
    function generate_tree(
        array $flatArray,
        int $parentId = 0,
        array $existsArr = []
    ): array {
        $tree = [];
        foreach ($flatArray as $item) {
            if ($item['parent_id'] === $parentId) {
                $node = $item;
                if ($existsArr) {
                    $node['is_show'] = in_array($item['id'], $existsArr) ? 1
                        : 0;
                }
                $node['children'] = generate_tree(
                    $flatArray,
                    $item['id'],
                    $existsArr
                );
                $tree[] = $node;
            }
        }
        return $tree;
    }
}

if (!function_exists('get_datetime')) {
    function get_datetime(string $type = 'datetime', int $times = 0): string
    {
        if (!$times) {
            $times = time();
        }
        $format = match ($type) {
            'date' => 'Y-m-d',
            'datetime' => 'Y-m-d H:i:s',
        };
        return date($format, $times);
    }
}