<?php
declare(strict_types=1);

namespace App\Controllers;

use App\Access;
use App\Attachments;
use App\Auth;
use App\Comments;
use App\Database;
use App\Expenses;
use App\Members;
use App\Uploads;

class NodeController
{
    /** 计划节点只可能有 planned / completed / cancelled */
    private const PLAN_STATUSES = ['planned', 'completed', 'cancelled'];
    /** 执行节点本身就是"已完成"，额外允许 cancelled */
    private const REALITY_STATUSES = ['completed', 'cancelled', 'ongoing', 'planned'];

    public function create(): void
    {
        $db         = Database::get();
        $activityId = (int)($_GET['activity_id'] ?? 0);
        $category   = $_GET['category'] ?? 'plan';
        $category   = in_array($category, ['plan', 'reality'], true) ? $category : 'plan';

        $activity = $this->fetchOwnActivity($activityId);

        view('nodes/form', $this->formData($db, $activity, $category, null));
    }

    public function edit(): void
    {
        $db   = Database::get();
        $node = $this->fetchOwnNode((int)($_GET['id'] ?? 0));

        $stmt = $db->prepare('SELECT * FROM activities WHERE id = ?');
        $stmt->execute([$node['activity_id']]);
        $activity = $stmt->fetch();

        view('nodes/form', $this->formData($db, $activity, $node['node_category'], $node));
    }

    public function store(): void
    {
        // 表单里带了照片时，整个请求体可能超过 post_max_size —— 这时 PHP 会
        // **静默丢掉 $_POST 和 $_FILES**，紧接着 csrf_check() 报「请求已过期」，
        // 用户看到的是「点了保存但没反应」。提前认出来，说清怎么办。
        // （这一步放在 csrf_check() 之前：它只读长度、不改任何状态。）
        if (Uploads::requestTooLarge()) {
            $this->flashTooLarge();
        }

        csrf_check();
        $db = Database::get();

        $activity = $this->fetchOwnActivity((int)($_POST['activity_id'] ?? 0));
        $category = $_POST['node_category'] ?? 'plan';
        if (!in_array($category, ['plan', 'reality'], true)) {
            exit('无效的节点分类');
        }

        $input = $this->collectInput($db, $activity, $category);
        if ($input['error'] !== null) {
            // 校验失败必须把用户刚填的内容原样带回去，否则一重定向表单就是空的，等于白填
            flash_old($_POST);
            flash('error', $input['error']);
            redirect('nodes/create', ['activity_id' => $activity['id'], 'category' => $category]);
        }

        $data = $input['data'];
        // 交通信息只留 trip_number（车次/航班号）—— 航班号本身就隐含航空公司，
        // 座位号/登机口对「一趟车多人同行」没有意义，所以这些字段不再收集。
        //
        // ⚠️ 历史列（line_name / carrier / seat_info / gate）仍然**留在 SQL 里**，
        //    只是值固定为 null（collectInput 里不再从表单取）。原因不是「要写它们」，
        //    而是 $data 里带着这几个键：Database 用的是原生预处理
        //    （ATTR_EMULATE_PREPARES => false），SQL 里少了占位符就会抛
        //    SQLSTATE[HY093]（参数个数对不上）→ 新建/编辑节点整条挂掉。
        //    顺带的好处是：编辑一次旧节点就把它身上的历史脏数据清干净。
        $sql = 'INSERT INTO trip_nodes
            (activity_id, node_type_id, node_category, original_plan_node_id,
             start_time, end_time, duration_minutes,
             start_location, end_location,
             title, description, travel_mode_id, vehicle_id,
             line_name, carrier, trip_number, seat_info, gate, status, cancel_reason)
            VALUES
            (:activity_id, :node_type_id, :node_category, :original_plan_node_id,
             :start_time, :end_time, :duration_minutes,
             :start_location, :end_location,
             :title, :description, :travel_mode_id, :vehicle_id,
             :line_name, :carrier, :trip_number, :seat_info, :gate, :status, :cancel_reason)';
        $stmt = $db->prepare($sql);
        $stmt->execute($data);

        $nodeId = (int)$db->lastInsertId();

        // 节点必须先有 id 才能挂附件，所以附件在插入之后处理
        $extra = $this->handleNodeUploads($nodeId);

        // 表单里勾的参与人（members_present=1 才认，避免没渲染这个区块的请求误清）
        $extra .= $this->syncMembers($nodeId);

        flash('error', '节点已保存' . $extra);
        redirect('activities/show', ['id' => (int)$activity['id']]);
    }

    public function update(): void
    {
        if (Uploads::requestTooLarge()) {
            $this->flashTooLarge();
        }

        csrf_check();
        $db = Database::get();

        $node     = $this->fetchOwnNode((int)($_POST['id'] ?? 0));
        $category = $node['node_category'];

        $stmt = $db->prepare('SELECT * FROM activities WHERE id = ?');
        $stmt->execute([$node['activity_id']]);
        $activity = $stmt->fetch();

        $input = $this->collectInput($db, $activity, $category, $node);
        if ($input['error'] !== null) {
            flash_old($_POST);   // 同 store()：失败不能让用户白填
            flash('error', $input['error']);
            redirect('nodes/edit', ['id' => (int)$node['id']]);
        }

        $data = $input['data'];
        unset($data['activity_id'], $data['node_category'], $data['original_plan_node_id']);
        $data['id'] = (int)$node['id'];

        // 同样必须保留历史列的占位符 —— 见 store() 里的说明（原生预处理不接受多余键）
        $sql = 'UPDATE trip_nodes SET
            node_type_id = :node_type_id,
            start_time = :start_time, end_time = :end_time, duration_minutes = :duration_minutes,
            start_location = :start_location, end_location = :end_location,
            title = :title, description = :description,
            travel_mode_id = :travel_mode_id, vehicle_id = :vehicle_id,
            line_name = :line_name, carrier = :carrier, trip_number = :trip_number,
            seat_info = :seat_info, gate = :gate, status = :status, cancel_reason = :cancel_reason
            WHERE id = :id';
        $stmt = $db->prepare($sql);
        $stmt->execute($data);

        // 表单里勾了「删除」的已有照片
        $removed = $this->deleteCheckedAttachments((int)$node['id']);

        // 再处理这次新选的照片
        $extra = $this->handleNodeUploads((int)$node['id']);

        // 参与人在表单里直接勾（编辑时重新勾选不会清掉已记的情绪/签到）
        $extra .= $this->syncMembers((int)$node['id']);

        $msg = '保存成功';
        if ($removed > 0) {
            $msg .= "，删除了 {$removed} 个附件";
        }
        flash('error', $msg . $extra);
        redirect('activities/show', ['id' => (int)$node['activity_id']]);
    }

    /**
     * 卡片上的状态快捷切换（计划节点：标记完成 / 撤销完成）
     */
    public function status(): void
    {
        csrf_check();
        $db = Database::get();

        $node   = $this->fetchOwnNode((int)($_POST['id'] ?? 0));
        $status = (string)($_POST['status'] ?? '');

        $allowed = $node['node_category'] === 'plan' ? self::PLAN_STATUSES : self::REALITY_STATUSES;
        if (!in_array($status, $allowed, true)) {
            flash('error', '无效的状态');
            redirect('activities/show', ['id' => (int)$node['activity_id']]);
        }

        $reason = trim($_POST['cancel_reason'] ?? '');
        $stmt = $db->prepare('UPDATE trip_nodes SET status = ?, cancel_reason = ? WHERE id = ?');
        $stmt->execute([
            $status,
            $status === 'cancelled' ? ($reason !== '' ? $reason : null) : null,
            (int)$node['id'],
        ]);

        $labels = ['planned' => '已恢复为待执行', 'completed' => '已标记为完成', 'cancelled' => '已取消', 'ongoing' => '已标记为进行中'];
        flash('error', $labels[$status] ?? '状态已更新');
        redirect('activities/show', ['id' => (int)$node['activity_id']]);
    }

    /**
     * 用计划节点生成一条执行记录（复制字段，保留 original_plan_node_id 指向计划节点）
     */
    public function fromPlan(): void
    {
        csrf_check();
        $db = Database::get();

        $plan = $this->fetchOwnNode((int)($_POST['plan_node_id'] ?? 0));
        if ($plan['node_category'] !== 'plan') {
            flash('error', '只有计划节点可以生成为执行记录');
            redirect('activities/show', ['id' => (int)$plan['activity_id']]);
        }

        // 已经生成过就不重复生成
        $chk = $db->prepare('SELECT id FROM trip_nodes WHERE original_plan_node_id = ? LIMIT 1');
        $chk->execute([(int)$plan['id']]);
        $exists = $chk->fetchColumn();
        if ($exists) {
            flash('error', '该计划节点已经有执行记录了');
            redirect('activities/show', ['id' => (int)$plan['activity_id']]);
        }

        $stmt = $db->prepare('INSERT INTO trip_nodes
            (activity_id, node_type_id, node_category, original_plan_node_id,
             start_time, end_time, duration_minutes,
             start_location, end_location,
             title, description, travel_mode_id, vehicle_id,
             trip_number, status)
            VALUES (?, ?, "reality", ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, "completed")');
        $stmt->execute([
            (int)$plan['activity_id'],
            (int)$plan['node_type_id'],
            (int)$plan['id'],
            $plan['start_time'],
            $plan['end_time'],
            $plan['duration_minutes'],
            $plan['start_location'],
            $plan['end_location'],
            $plan['title'],
            $plan['description'],
            $plan['travel_mode_id'],
            $plan['vehicle_id'],
            $plan['trip_number'],
        ]);

        flash('error', '已根据计划节点生成执行记录，可继续编辑补充实际情况');
        redirect('activities/show', ['id' => (int)$plan['activity_id']]);
    }

    public function destroy(): void
    {
        csrf_check();
        $db = Database::get();

        $node = $this->fetchOwnNode((int)($_POST['id'] ?? 0));

        // 附件是软关联：交给 Attachments 统一清（同时会删本地文件或 OSS 对象）
        Attachments::purgeTarget(Attachments::TARGET_NODE, (int)$node['id']);

        $stmt = $db->prepare('DELETE FROM comments WHERE target_type = "trip_node" AND target_id = ?');
        $stmt->execute([(int)$node['id']]);

        // 若有执行记录指向本计划节点，外键是 ON DELETE SET NULL，会自动置空
        $stmt = $db->prepare('DELETE FROM trip_nodes WHERE id = ?');
        $stmt->execute([(int)$node['id']]);

        flash('error', '节点已删除');
        redirect('activities/show', ['id' => (int)$node['activity_id']]);
    }

    /**
     * 节点详情页：把挂在这个节点上的参与人、花销、讨论集中到一页
     */
    public function show(): void
    {
        $db     = Database::get();
        $nodeId = (int)($_GET['id'] ?? 0);

        $node = Access::node($nodeId);   // 含 family_id / activity_id / activity_title

        // 节点类型（本家庭）
        $stmt = $db->prepare('SELECT name, icon FROM node_types WHERE id = ?');
        $stmt->execute([(int)$node['node_type_id']]);
        $type = $stmt->fetch();
        if (!$type) $type = ['name' => '未分类', 'icon' => '·'];

        // 出行方式（连同车辆信息拼成一行展示文本）
        $travelModeLabel = '';
        $travelModeType  = '';
        if (!empty($node['travel_mode_id'])) {
            $stmt = $db->prepare('
                SELECT tm.mode_type, v.plate_number, v.model_name
                FROM travel_modes tm
                LEFT JOIN vehicles v ON v.id = tm.vehicle_id
                WHERE tm.id = ?');
            $stmt->execute([(int)$node['travel_mode_id']]);
            $tm = $stmt->fetch();
            if ($tm) {
                $label = TravelModeController::MODE_LABELS[$tm['mode_type']] ?? $tm['mode_type'];
                if (!empty($tm['plate_number'])) {
                    $label .= ' · ' . $tm['plate_number'];
                } elseif (!empty($tm['model_name'])) {
                    $label .= ' · ' . $tm['model_name'];
                }
                $travelModeLabel = $label;
                $travelModeType  = (string)$tm['mode_type'];
            }
        }

        $nodeAttachments   = Attachments::forTarget(Attachments::TARGET_NODE, $nodeId);
        $attachmentCount   = count($nodeAttachments);

        $familyId = (int)$node['family_id'];

        view('nodes/show', [
            'node' => array_merge($node, [
                'node_type_name'    => (string)$type['name'],
                'node_type_icon'    => (string)$type['icon'],
                'travel_mode_label' => $travelModeLabel,
                'travel_mode_type'  => $travelModeType,
            ]),
            'attachmentCount' => $attachmentCount,
            'attachments'     => $nodeAttachments,
            'members'         => Members::forNode($nodeId),
            'familyUsers'     => Members::familyUsers($familyId),
            'roleTags'        => Members::roleTagMap($familyId),
            'emotions'        => Members::EMOTIONS,
            'expenses'        => Expenses::forNode($nodeId),
            'expenseSummary'  => Expenses::summaryForNode($nodeId),
            'categories'      => Expenses::CATEGORIES,
            'currencies'      => Expenses::currencyLabels(),
            'expenseSymbols'  => Expenses::SYMBOLS,
            'currentUserId'   => (int)Auth::id(),
            'commentTree'     => Comments::tree(Comments::TARGET_NODE, $nodeId),
            'pageTitle'       => $node['title'] !== null && $node['title'] !== ''
                ? (string)$node['title']
                : '节点详情',
        ]);
    }

    // ------------------------------------------------------------------
    // 内部辅助
    // ------------------------------------------------------------------

    /** 组装 nodes/form 模板所需数据 */
    private function formData(\PDO $db, array $activity, string $category, ?array $node): array
    {
        $stmt = $db->prepare('SELECT * FROM node_types WHERE family_id = ? ORDER BY is_system DESC, id ASC');
        $stmt->execute([$activity['family_id']]);
        $nodeTypes = $stmt->fetchAll();

        $stmt = $db->prepare('
            SELECT tm.*, v.plate_number, v.model_name
            FROM travel_modes tm
            LEFT JOIN vehicles v ON v.id = tm.vehicle_id
            WHERE tm.family_id = ?
            ORDER BY FIELD(tm.mode_type, "drive_own","drive_rental","train","plane","bus","subway","taxi","bike","walk","ship","other"), tm.id ASC
        ');
        $stmt->execute([$activity['family_id']]);
        $travelModes = $stmt->fetchAll();

        // 执行节点可以关联计划节点（编辑已有执行节点时不再改关联关系）
        $planNodes = [];
        if ($category === 'reality' && $node === null) {
            $s = $db->prepare('SELECT id, title, start_time FROM trip_nodes WHERE activity_id = ? AND node_category = "plan" ORDER BY start_time');
            $s->execute([$activity['id']]);
            $planNodes = $s->fetchAll();
        }

        $isEdit = $node !== null;

        /* 参与人在表单里直接勾（不必先保存再回详情页加人）。
           编辑时把已有人带过去预勾选；新建时空着。 */
        $familyUsers = Members::familyUsers((int)$activity['family_id']);
        $nodeMemberIds = [];
        if ($isEdit) {
            $s = $db->prepare('SELECT user_id FROM node_members WHERE trip_node_id = ?');
            $s->execute([(int)$node['id']]);
            foreach ($s->fetchAll() as $row) {
                $nodeMemberIds[] = (int)$row['user_id'];
            }
        }

        return [
            'modeLabels' => TravelModeController::MODE_LABELS,
            'activity'   => $activity,
            'category'   => $category,
            'nodeTypes'  => $nodeTypes,
            'travelModes' => $travelModes,
            'planNodes'  => $planNodes,
            'node'       => $node,
            'isEdit'     => $isEdit,
            'familyUsers' => $familyUsers,
            'nodeMemberIds' => $nodeMemberIds,
            // 编辑时把已有照片带进表单：能看、能勾选删除。新建时节点还没 id，
            // 附件挂不上去，所以只能是空数组（模板里会提示先保存）。
            'attachments' => $isEdit ? Attachments::forTarget(Attachments::TARGET_NODE, (int)$node['id']) : [],
            'maxPhotoMb'  => (int)\App\Settings::get('photo_max_mb', '12'),
            'pageTitle'  => ($isEdit ? '编辑' : '新建') . ($category === 'plan' ? '计划' : '执行') . '节点',
        ];
    }

    /**
     * 校验并整理表单输入
     * @return array{error: ?string, data: array}
     */
    private function collectInput(\PDO $db, array $activity, string $category, ?array $node = null): array
    {
        // 「日期 + 24 小时制时/分」组合控件（read_dt_input 里说明了为什么不用 datetime-local）
        $startTime = read_dt_input('start_time');
        $endTime   = read_dt_input('end_time');
        if ($startTime === null || $endTime === null) {
            return ['error' => '开始和结束时间必填', 'data' => []];
        }
        if (strtotime($endTime) < strtotime($startTime)) {
            return ['error' => '结束时间不能早于开始时间', 'data' => []];
        }

        $nodeTypeId = (int)($_POST['node_type_id'] ?? 0);
        $chk = $db->prepare('SELECT id FROM node_types WHERE id = ? AND family_id = ?');
        $chk->execute([$nodeTypeId, $activity['family_id']]);
        if (!$chk->fetch()) {
            return ['error' => '节点类型不存在', 'data' => []];
        }

        $travelModeId = !empty($_POST['travel_mode_id']) ? (int)$_POST['travel_mode_id'] : null;
        $vehicleId = null;
        if ($travelModeId) {
            $s = $db->prepare('SELECT vehicle_id FROM travel_modes WHERE id = ? AND family_id = ?');
            $s->execute([$travelModeId, $activity['family_id']]);
            $row = $s->fetch();
            if (!$row) {
                return ['error' => '出行方式不存在', 'data' => []];
            }
            $vehicleId = $row['vehicle_id'] !== null ? (int)$row['vehicle_id'] : null;
        }

        // 状态：计划节点默认待执行，执行节点默认已完成
        $defaultStatus = $category === 'plan' ? 'planned' : 'completed';
        $status = (string)($_POST['status'] ?? $defaultStatus);
        $allowed = $category === 'plan' ? self::PLAN_STATUSES : self::REALITY_STATUSES;
        if (!in_array($status, $allowed, true)) {
            $status = $node['status'] ?? $defaultStatus;
        }

        $originalPlanId = null;
        if ($category === 'reality' && $node === null && !empty($_POST['original_plan_node_id'])) {
            $originalPlanId = (int)$_POST['original_plan_node_id'];
            // 关联的计划节点必须属于同一个活动，否则视为未关联
            $s = $db->prepare('SELECT id FROM trip_nodes WHERE id = ? AND activity_id = ? AND node_category = "plan"');
            $s->execute([$originalPlanId, $activity['id']]);
            if (!$s->fetch()) {
                $originalPlanId = null;
            }
        }

        $data = [
            'activity_id'            => (int)$activity['id'],
            'node_type_id'           => $nodeTypeId,
            'node_category'          => $category,
            'original_plan_node_id'  => $originalPlanId,
            'start_time'             => $startTime,
            'end_time'               => $endTime,
            'duration_minutes'       => $this->calcDuration($startTime, $endTime),
            'start_location'         => $this->buildLocation('start'),
            'end_location'           => $this->buildLocation('end'),
            'title'                  => trim($_POST['title'] ?? ''),
            'description'            => trim($_POST['description'] ?? ''),
            'travel_mode_id'         => $travelModeId,
            'vehicle_id'             => $vehicleId,
            'line_name'              => null,
            'carrier'                => null,
            'trip_number'            => $this->strOrNull('trip_number'),
            'seat_info'              => null,
            'gate'                   => null,
            'status'                 => $status,
            'cancel_reason'          => $status === 'cancelled' ? $this->strOrNull('cancel_reason') : null,
        ];

        return ['error' => null, 'data' => $data];
    }

    private function fetchOwnActivity(int $id): array
    {
        if ($id <= 0) {
            http_response_code(404);
            exit('活动不存在');
        }
        $stmt = Database::get()->prepare('SELECT * FROM activities WHERE id = ?');
        $stmt->execute([$id]);
        $activity = $stmt->fetch();
        if (!$activity || (int)$activity['family_id'] !== Auth::familyId()) {
            http_response_code(404);
            exit('活动不存在');
        }
        return $activity;
    }

    private function fetchOwnNode(int $id): array
    {
        if ($id <= 0) {
            http_response_code(404);
            exit('节点不存在');
        }
        $stmt = Database::get()->prepare('
            SELECT tn.*, a.family_id
            FROM trip_nodes tn
            JOIN activities a ON a.id = tn.activity_id
            WHERE tn.id = ?');
        $stmt->execute([$id]);
        $node = $stmt->fetch();
        if (!$node || (int)$node['family_id'] !== Auth::familyId()) {
            http_response_code(404);
            exit('节点不存在');
        }
        return $node;
    }

    private function calcDuration(string $start, string $end): int
    {
        $s = strtotime($start);
        $e = strtotime($end);
        return max(0, (int)round(($e - $s) / 60));
    }

    private function buildLocation(string $which): ?string
    {
        $name    = trim($_POST["{$which}_location_name"] ?? '');
        $address = trim($_POST["{$which}_location_address"] ?? '');
        if ($name === '' && $address === '') return null;

        $lat = $_POST["{$which}_location_lat"] ?? null;
        $lng = $_POST["{$which}_location_lng"] ?? null;
        return json_encode([
            'name'    => $name,
            'address' => $address,
            'lat'     => ($lat === '' || $lat === null) ? null : $lat,
            'lng'     => ($lng === '' || $lng === null) ? null : $lng,
        ], JSON_UNESCAPED_UNICODE);
    }

    private function strOrNull(string $key): ?string
    {
        $v = trim($_POST[$key] ?? '');
        return $v === '' ? null : $v;
    }

    /**
     * 请求体超限的统一提示。
     *
     * 这时 $_POST 已经被 PHP 丢掉了，**无从回填**（服务端拿不到任何字段），
     * 只能尽量退回一个合理页面；已填内容的恢复靠表单里的 sessionStorage 草稿。
     */
    private function flashTooLarge(): void
    {
        flash('error', '这次提交的内容太大（超过服务器上限 ' . ini_get('post_max_size')
            . '），节点没有保存。请把照片分成几批上传，或先保存节点、再进「📷 照片」页上传。');

        $actId = (int)($_POST['activity_id'] ?? 0);
        if ($actId > 0) {
            $cat = (string)($_POST['node_category'] ?? 'plan');
            redirect('nodes/create', [
                'activity_id' => $actId,
                'category'    => in_array($cat, ['plan', 'reality'], true) ? $cat : 'plan',
            ]);
        }
        redirect('activities/index');
    }

    /**
     * 处理节点表单里一起提交的附件（新选的 files[] 与前端裁过的 cropped[]）。
     *
     * @return string 追加到 flash 文案后的后缀；没有附件时是空串
     */
    private function handleNodeUploads(int $nodeId): string
    {
        $uploaderId = (int)Auth::id();
        $target     = Attachments::TARGET_NODE;

        $files = Uploads::handleFiles($_FILES['files'] ?? [], $target, $nodeId, $uploaderId, 0);
        $crop  = Uploads::handleCropped(
            (string)($_POST['cropped'] ?? ''),
            $target,
            $nodeId,
            $uploaderId,
            $files['count']
        );

        $uploaded = $files['uploaded'] + $crop['uploaded'];
        $errors   = array_merge($files['errors'], $crop['errors']);

        if ($uploaded === 0 && $errors === []) {
            return '';
        }

        $msg = $uploaded > 0
            ? "，另存了 {$uploaded} 张照片/附件"
            : '，但照片没传上去';
        if ($errors !== []) {
            $msg .= '（' . implode('；', array_slice($errors, 0, 3)) . '）';
        }
        return $msg;
    }

    /**
     * 删除表单里勾选的已有附件。
     *
     * ⚠️ 必须逐条校验归属：attachments 是「target_type + target_id」的软关联，
     *    表单里的 id 是用户可以随便改的，不校验就等于给了跨家庭删文件的入口。
     */
    /**
     * 表单里勾的参与人 → 同步成节点成员（只增删，不动已记的情绪/签到）。
     *
     * 只在表单确实渲染了参与人区块时（members_present=1）才同步：
     * 没有渲染却收到空数组的话，会把节点已有成员全删掉。
     * 跨家庭的 user_id 由 Members::save() 逐条拦掉。
     */
    private function syncMembers(int $nodeId): string
    {
        if (($_POST['members_present'] ?? '') !== '1') {
            return '';
        }
        $picked = $_POST['members'] ?? [];
        if (!is_array($picked)) {
            return '';
        }
        $res = Members::syncForNode($nodeId, $picked);
        if ($res['added'] === 0 && $res['removed'] === 0) {
            return '';
        }
        $parts = [];
        if ($res['added'] > 0) {
            $parts[] = "加入 {$res['added']} 位参与人";
        }
        if ($res['removed'] > 0) {
            $parts[] = "移出 {$res['removed']} 位参与人";
        }
        return '，' . implode('，', $parts);
    }

    private function deleteCheckedAttachments(int $nodeId): int
    {
        $ids = $_POST['delete_attachments'] ?? [];
        if (!is_array($ids)) {
            return 0;
        }

        $removed = 0;
        foreach ($ids as $id) {
            $id  = (int)$id;
            $att = $id > 0 ? Attachments::find($id) : null;
            if (!$att
                || $att['target_type'] !== Attachments::TARGET_NODE
                || (int)$att['target_id'] !== $nodeId) {
                continue;
            }
            Attachments::delete($id);
            $removed++;
        }
        return $removed;
    }
}