<?php

namespace app\admin\controller;

use app\common\controller\Backend;
use think\Db;
use think\exception\PDOException;

/**
 * 开票申请
 *
 * 开票申请仅由用户/商户端发起，后台只负责财务开具处理：
 * 待开具(wait) → 已开票(issued，必填发票号)/驳回(reject，必填原因)
 * 驳回后额度自动释放，并通知申请人
 *
 * @icon fa fa-file-text-o
 */
class Invoice extends Backend
{

    /**
     * Invoice模型对象
     * @var \app\admin\model\Invoice
     */
    protected $model = null;

    /**
     * 开票处理状态机：当前状态 => 允许流转到的目标状态
     * issued/reject 为终态
     * @var array
     */
    protected $statusFlow = [
        'wait' => ['issued', 'reject'],
    ];

    public function _initialize()
    {
        parent::_initialize();
        $this->model = new \app\admin\model\Invoice;
        $this->view->assign("typeList", $this->model->getTypeList());
        $this->view->assign("statusList", $this->model->getStatusList());
    }

    /**
     * 开票申请列表：关联申请人/商户
     */
    public function index()
    {
        $this->request->filter(['strip_tags', 'trim']);
        if (false === $this->request->isAjax()) {
            return $this->view->fetch();
        }
        if ($this->request->request('keyField')) {
            return $this->selectpage();
        }
        [$where, $sort, $order, $offset, $limit] = $this->buildparams();
        $list = $this->model
            ->with(['user', 'merchant'])
            ->where($where)
            ->order($sort, $order)
            ->paginate($limit);
        $result = ['total' => $list->total(), 'rows' => $list->items()];
        return json($result);
    }

    /**
     * 财务开票处理：申请信息只读，仅允许填写开票结果
     * - 开票完成：必须填写发票号，状态置为已开票
     * - 驳回：必须填写原因，额度自动释放
     */
    public function edit($ids = null)
    {
        $row = $this->model->get($ids);
        if (!$row) {
            $this->error(__('No Results were found'));
        }
        if (false === $this->request->isPost()) {
            $this->view->assign('row', $row);
            $this->view->assign('flowOptions', $this->statusFlow[$row['status']] ?? []);
            return $this->view->fetch();
        }

        $status    = (string)$this->request->post('row.status');
        $invoiceNo = trim((string)$this->request->post('row.invoice_no'));
        $auditMsg  = trim((string)$this->request->post('row.audit_msg'));

        // 状态机校验：终态禁止操作，流转目标必须合法
        if (!isset($this->statusFlow[$row['status']])) {
            $this->error('该开票申请已处理完毕，不允许再次变更');
        }
        if (!in_array($status, $this->statusFlow[$row['status']], true)) {
            $this->error('状态流转不合法，请刷新后重试');
        }
        if ($status === 'issued' && $invoiceNo === '') {
            $this->error('标记开票完成必须填写发票号码');
        }
        if ($status === 'reject' && $auditMsg === '') {
            $this->error('驳回时必须填写驳回原因');
        }

        Db::startTrans();
        try {
            // 乐观锁更新状态，防止并发重复处理
            $affected = Db::name('invoice')
                ->where('id', $row['id'])
                ->where('status', $row['status'])
                ->update([
                    'status'     => $status,
                    'invoice_no' => $invoiceNo !== '' ? $invoiceNo : $row['invoice_no'],
                    'audit_msg'  => $auditMsg,
                    'updatetime' => time(),
                ]);
            if (!$affected) {
                throw new \Exception('开票申请状态已被其他人变更，请刷新后重试');
            }

            // 通知申请人（商户开票通知绑定账号用户）
            $this->sendUserMessage(
                (int)$row['user_id'],
                $status === 'issued' ? '发票已开具' : '开票申请已驳回',
                $status === 'issued'
                    ? '您申请的开票 ¥' . $row['amount'] . ' 已开具完成，发票号码：' . $invoiceNo . '，电子发票已发送至 ' . $row['email']
                    : '您的开票申请 ¥' . $row['amount'] . ' 未通过审核：' . ($auditMsg !== '' ? $auditMsg : '无')
            );
            Db::commit();
        } catch (PDOException|\Exception $e) {
            Db::rollback();
            $this->error($e->getMessage());
        }
        $this->success();
    }

    /**
     * 开票申请仅由用户/商户端发起，禁止后台手工添加
     */
    public function add()
    {
        $this->error('开票申请仅支持用户/商户端发起，后台不可手动添加');
    }

    /**
     * 开票记录禁止删除，保障开票额度统计与账务完整
     */
    public function del($ids = null)
    {
        $this->error('开票申请记录禁止删除');
    }

    /**
     * 禁止批量修改状态，必须逐单填写开票结果
     */
    public function multi($ids = null)
    {
        $this->error('开票处理不支持批量操作，请逐单填写发票号后处理');
    }

    /**
     * 向申请人发送站内消息
     * @param int $userId 用户ID
     * @param string $title 消息标题
     * @param string $content 消息内容
     */
    protected function sendUserMessage($userId, $title, $content)
    {
        if (!$userId) {
            return;
        }
        Db::name('message')->insert([
            'receive_type' => 'user',
            'receive_id'   => $userId,
            'type'         => 'system',
            'title'        => mb_substr((string)$title, 0, 100),
            'content'      => mb_substr((string)$content, 0, 500),
            'order_id'     => 0,
            'is_read'      => 0,
            'createtime'   => time(),
        ]);
    }
}