<?php
declare(strict_types=1);

function e(string $v): string
{
    return htmlspecialchars($v, ENT_QUOTES, 'UTF-8');
}

function now(): string
{
    return date('Y-m-d H:i:s');
}

function flash(string $type, string $msg): void
{
    $_SESSION['flash'] = ['type' => $type, 'msg' => $msg];
}

function getFlash(): ?array
{
    if (!isset($_SESSION['flash'])) {
        return null;
    }
    $f = $_SESSION['flash'];
    unset($_SESSION['flash']);
    return $f;
}

function normalizeFileName(string $name): string
{
    $name = strtolower($name);
    $name = preg_replace('/[^a-z0-9\.]+/', '_', $name);
    return trim((string)$name, '_');
}

function archiveStatus(?string $endDate): string
{
    if (!$endDate) {
        return '待更新';
    }
    $today = date('Y-m-d');
    if ($endDate >= $today) {
        return '履行中';
    }
    return '待更新';
}

function canPreview(string $ext): bool
{
    return in_array(strtolower($ext), ['pdf', 'jpg', 'jpeg', 'png', 'gif'], true);
}

function amount(?float $v): string
{
    if ($v === null) {
        return '';
    }
    return number_format($v, 2, '.', '');
}

function dirPathMap(array $dirs): array
{
    $map = [];
    foreach ($dirs as $d) {
        $map[(int)$d['id']] = $d;
    }
    $path = [];
    foreach ($dirs as $d) {
        $id = (int)$d['id'];
        $parts = [$d['name']];
        $p = $d['parent_id'];
        while ($p && isset($map[(int)$p])) {
            $parts[] = $map[(int)$p]['name'];
            $p = $map[(int)$p]['parent_id'];
        }
        $path[$id] = implode(' / ', array_reverse($parts));
    }
    return $path;
}

function collectSubDirIds(array $dirs, int $rootId): array
{
    $children = [];
    foreach ($dirs as $d) {
        $pid = $d['parent_id'] === null ? null : (int)$d['parent_id'];
        if ($pid !== null) {
            $children[$pid][] = (int)$d['id'];
        }
    }
    $result = [$rootId];
    $queue = [$rootId];
    while ($queue) {
        $cur = array_shift($queue);
        foreach ($children[$cur] ?? [] as $cid) {
            $result[] = $cid;
            $queue[] = $cid;
        }
    }
    return array_values(array_unique($result));
}