<?php

namespace app\service;

use app\model\BusinessTrip;
use app\model\BusinessTripItinerary;
use app\model\ApprovalOrder;
use app\model\ApprovalFlow;
use app\model\ApprovalRecord;
use app\model\User;
use app\util\Db;
use Illuminate\Database\Connection;

class BusinessTripService
{
    private Connection $db;

    public function __construct()
    {
        Db::init();
        $this->db = Db::connection();
    }

    /**
     * 创建出差申请（草稿）
     */
    public function createDraft(int $userId, array $data): BusinessTrip
    {
        return $this->db->transaction(function () use ($userId, $data) {
            try {
                // 计算最早和最晚时间
                $itineraries = $data['itineraries'] ?? [];
                if (empty($itineraries)) {
                    throw new \Exception('请至少添加一条行程');
                }

                $startDate = null;
                $endDate = null;
                $destinations = [];

                foreach ($itineraries as $itinerary) {
                    if ($itinerary['start_time']) {
                        if (!$startDate || $itinerary['start_time'] < $startDate) {
                            $startDate = $itinerary['start_time'];
                        }
                    }
                    if ($itinerary['end_time']) {
                        if (!$endDate || $itinerary['end_time'] > $endDate) {
                            $endDate = $itinerary['end_time'];
                        }
                    }
                    if (!empty($itinerary['destination'])) {
                        $destinations[] = $itinerary['destination'];
                    }
                }

                // 创建出差申请
                $businessTrip = BusinessTrip::create([
                    'user_id' => $userId,
                    'reason' => $data['reason'] ?? '',
                    'start_date' => $startDate ? date('Y-m-d', strtotime($startDate)) : null,
                    'end_date' => $endDate ? date('Y-m-d', strtotime($endDate)) : null,
                    'destination' => implode(', ', array_unique($destinations)),
                    'estimated_cost' => $data['estimated_cost'] ?? 0,
                    'status' => BusinessTrip::STATUS_DRAFT,
                ]);

                // 创建行程明细
                foreach ($itineraries as $itinerary) {
                    BusinessTripItinerary::create([
                        'business_trip_id' => $businessTrip->id,
                        'start_time' => $itinerary['start_time'],
                        'end_time' => $itinerary['end_time'] ?? null,
                        'departure' => $itinerary['departure'] ?? '',
                        'destination' => $itinerary['destination'] ?? '',
                        'transport' => $itinerary['transport'] ?? '',
                        'trip_type' => $itinerary['trip_type'] ?? 'oneway',
                        'remark' => $itinerary['remark'] ?? '',
                    ]);
                }

                return $businessTrip->load('itineraries');
            } catch (\Exception $e) {
                error_log('BusinessTripService::createDraft error: ' . $e->getMessage() . ' in ' . $e->getFile() . ':' . $e->getLine());
                throw $e;
            }
        });
    }

    /**
     * 提交出差申请
     */
    public function submit(int $userId, int $businessTripId, array $approvers, array $ccUsers = []): BusinessTrip
    {
        return $this->db->transaction(function () use ($userId, $businessTripId, $approvers, $ccUsers) {
            $businessTrip = BusinessTrip::with('itineraries')->findOrFail($businessTripId);

            if ($businessTrip->user_id !== $userId) {
                throw new \Exception('无权操作此申请');
            }

            if (!$businessTrip->canSubmit()) {
                throw new \Exception('当前状态无法提交');
            }

            // 获取审批流程（简化版：直接使用第一个审批人作为单人审批）
            $flow = ApprovalFlow::where('business_type', 'business_trip')
                ->where('status', 1)
                ->first();

            if (!$flow) {
                // 创建默认流程
                $flow = ApprovalFlow::create([
                    'business_type' => 'business_trip',
                    'name' => '出差审批',
                    'description' => '出差申请审批流程',
                    'status' => 1,
                ]);
            }

            // 创建审批单
            $approvalOrder = ApprovalOrder::create([
                'business_type' => 'business_trip',
                'business_id' => $businessTrip->id,
                'title' => '出差申请 - ' . $businessTrip->user->name,
                'applicant_id' => $userId,
                'status' => ApprovalOrder::STATUS_PENDING,
                'current_nodes' => [1], // 简化：使用节点1
                'flow_id' => $flow->id,
                'form_data' => [
                    'reason' => $businessTrip->reason,
                    'start_date' => $businessTrip->start_date,
                    'end_date' => $businessTrip->end_date,
                    'destination' => $businessTrip->destination,
                    'approvers' => $approvers,
                    'cc_users' => $ccUsers,
                ],
            ]);

            // 更新出差申请状态
            $businessTrip->status = BusinessTrip::STATUS_PENDING;
            $businessTrip->approval_order_id = $approvalOrder->id;
            $businessTrip->save();

            // 记录提交操作
            ApprovalRecord::create([
                'order_id' => $approvalOrder->id,
                'node_id' => 1,
                'node_type' => 'single_approve',
                'approver_id' => $userId,
                'action' => 'submit',
                'comment' => null,
            ]);

            return $businessTrip->fresh(['itineraries', 'approvalOrder']);
        });
    }

    /**
     * 获取出差申请列表
     */
    public function getList(int $userId, string $type = 'my', int $page = 1, int $pageSize = 20): array
    {
        $query = BusinessTrip::with(['user', 'itineraries']);

        switch ($type) {
            case 'my':
                // 我发起的：当前用户创建的申请
                $query->where('user_id', $userId);
                break;
            case 'pending':
                // 待我审批：需要查询当前用户是审批人且还未审批的申请
                $pendingOrderIds = ApprovalOrder::where('status', ApprovalOrder::STATUS_PENDING)
                    ->where('business_type', 'business_trip')
                    ->pluck('id')
                    ->toArray();

                if (empty($pendingOrderIds)) {
                    $query->whereRaw('1 = 0'); // 返回空结果
                } else {
                    // 获取这些审批单中当前用户待审批的，排除已审批的
                    $approvedOrderIds = ApprovalRecord::whereIn('order_id', $pendingOrderIds)
                        ->where('approver_id', $userId)
                        ->whereIn('action', ['approve', 'reject'])
                        ->pluck('order_id')
                        ->toArray();

                    $pendingOrderIds = array_diff($pendingOrderIds, $approvedOrderIds);

                    $query->whereIn('approval_order_id', $pendingOrderIds);
                }
                break;
            case 'approved':
                // 我已审批：当前用户已经审批过的申请
                $approvedOrderIds = ApprovalRecord::where('approver_id', $userId)
                    ->whereIn('action', ['approve', 'reject'])
                    ->pluck('order_id')
                    ->toArray();

                if (empty($approvedOrderIds)) {
                    $query->whereRaw('1 = 0'); // 返回空结果
                } else {
                    $query->whereIn('approval_order_id', $approvedOrderIds);
                }
                break;
        }

        $total = $query->count();
        $list = $query->orderBy('created_at', 'desc')
            ->offset(($page - 1) * $pageSize)
            ->limit($pageSize)
            ->get();

        return [
            'list' => $list,
            'total' => $total,
            'page' => $page,
            'page_size' => $pageSize,
        ];
    }

    /**
     * 获取出差申请详情
     */
    public function getDetail(int $id): array
    {
        $businessTrip = BusinessTrip::with(['user', 'itineraries'])
            ->findOrFail($id);

        $result = $businessTrip->toArray();

        // 获取审批单信息
        if ($businessTrip->approval_order_id) {
            $approvalOrder = ApprovalOrder::with(['records.approver'])
                ->find($businessTrip->approval_order_id);

            if ($approvalOrder) {
                $result['approval_order'] = $approvalOrder->toArray();

                // 获取审批人和抄送人信息
                $formData = $approvalOrder->form_data ?? [];
                $result['approvers'] = $formData['approvers'] ?? [];
                $result['cc_users'] = $formData['cc_users'] ?? [];

                // 获取审批记录
                $result['approval_records'] = $approvalOrder->records->toArray();
            }
        }

        return $result;
    }

    /**
     * 更新出差申请
     */
    public function update(int $userId, int $id, array $data): BusinessTrip
    {
        $businessTrip = BusinessTrip::findOrFail($id);

        if ($businessTrip->user_id !== $userId) {
            throw new \Exception('无权操作此申请');
        }

        if (!$businessTrip->canEdit()) {
            throw new \Exception('当前状态无法编辑');
        }

        return $this->db->transaction(function () use ($businessTrip, $data) {
            // 更新基本信息
            if (isset($data['reason'])) {
                $businessTrip->reason = $data['reason'];
            }

            // 更新行程
            if (isset($data['itineraries'])) {
                // 删除旧行程
                BusinessTripItinerary::where('business_trip_id', $businessTrip->id)->delete();

                // 创建新行程
                $startDate = null;
                $endDate = null;
                $destinations = [];

                foreach ($data['itineraries'] as $itinerary) {
                    BusinessTripItinerary::create([
                        'business_trip_id' => $businessTrip->id,
                        'start_time' => $itinerary['start_time'],
                        'end_time' => $itinerary['end_time'] ?? null,
                        'departure' => $itinerary['departure'] ?? '',
                        'destination' => $itinerary['destination'] ?? '',
                        'transport' => $itinerary['transport'] ?? '',
                        'trip_type' => $itinerary['trip_type'] ?? 'oneway',
                        'remark' => $itinerary['remark'] ?? '',
                    ]);

                    if ($itinerary['start_time']) {
                        if (!$startDate || $itinerary['start_time'] < $startDate) {
                            $startDate = $itinerary['start_time'];
                        }
                    }
                    if ($itinerary['end_time']) {
                        if (!$endDate || $itinerary['end_time'] > $endDate) {
                            $endDate = $itinerary['end_time'];
                        }
                    }
                    if (!empty($itinerary['destination'])) {
                        $destinations[] = $itinerary['destination'];
                    }
                }

                // 更新日期和目的地
                $businessTrip->start_date = $startDate ? date('Y-m-d', strtotime($startDate)) : null;
                $businessTrip->end_date = $endDate ? date('Y-m-d', strtotime($endDate)) : null;
                $businessTrip->destination = implode(', ', array_unique($destinations));
            }

            $businessTrip->save();

            return $businessTrip->fresh('itineraries');
        });
    }

    /**
     * 取消出差申请
     */
    public function cancel(int $userId, int $id): BusinessTrip
    {
        $businessTrip = BusinessTrip::findOrFail($id);

        if ($businessTrip->user_id !== $userId) {
            throw new \Exception('无权操作此申请');
        }

        if (!$businessTrip->canCancel()) {
            throw new \Exception('当前状态无法取消');
        }

        $businessTrip->status = BusinessTrip::STATUS_CANCELLED;
        $businessTrip->save();

        // 同时取消审批单
        if ($businessTrip->approval_order_id) {
            $approvalOrder = ApprovalOrder::find($businessTrip->approval_order_id);
            if ($approvalOrder) {
                $approvalOrder->status = ApprovalOrder::STATUS_CANCELLED;
                $approvalOrder->current_nodes = [];
                $approvalOrder->save();
            }
        }

        return $businessTrip->fresh();
    }

    /**
     * 删除草稿
     */
    public function deleteDraft(int $userId, int $id): bool
    {
        $businessTrip = BusinessTrip::findOrFail($id);

        if ($businessTrip->user_id !== $userId) {
            throw new \Exception('无权操作此申请');
        }

        if ($businessTrip->status !== BusinessTrip::STATUS_DRAFT) {
            throw new \Exception('只能删除草稿');
        }

        return $this->db->transaction(function () use ($businessTrip) {
            // 删除行程明细
            BusinessTripItinerary::where('business_trip_id', $businessTrip->id)->delete();

            // 删除申请
            return $businessTrip->delete();
        });
    }

    /**
     * 审批操作
     */
    public function approve(int $userId, int $businessTripId, string $action, string $comment = ''): BusinessTrip
    {
        return $this->db->transaction(function () use ($userId, $businessTripId, $action, $comment) {
            $businessTrip = BusinessTrip::with(['itineraries', 'approvalOrder'])->findOrFail($businessTripId);

            if (!$businessTrip->approval_order_id) {
                throw new \Exception('未找到审批单');
            }

            $approvalOrder = $businessTrip->approvalOrder;

            if ($approvalOrder->status !== ApprovalOrder::STATUS_PENDING) {
                throw new \Exception('当前状态无法审批');
            }

            // 检查用户是否是当前审批人
            $currentNodes = $approvalOrder->current_nodes ?? [];
            $isApprover = false;

            foreach ($currentNodes as $nodeId) {
                $node = ApprovalNode::where('order_id', $approvalOrder->id)
                    ->where('id', $nodeId)
                    ->first();

                if (!$node) {
                    continue;
                }

                // 检查是否是单人审批节点
                if ($node->node_type === 'single_approve') {
                    $approvers = $node->approvers ?? [];
                    if (in_array($userId, $approvers)) {
                        $isApprover = true;
                        break;
                    }
                }
            }

            if (!$isApprover) {
                throw new \Exception('您不是当前审批人');
            }

            // 检查是否已经审批过
            $existingRecord = ApprovalRecord::where('order_id', $approvalOrder->id)
                ->where('approver_id', $userId)
                ->whereIn('action', ['approve', 'reject'])
                ->first();

            if ($existingRecord) {
                throw new \Exception('您已经审批过了');
            }

            // 记录审批操作
            ApprovalRecord::create([
                'order_id' => $approvalOrder->id,
                'node_id' => $currentNodes[0] ?? 1,
                'node_type' => 'single_approve',
                'approver_id' => $userId,
                'action' => $action,
                'comment' => $comment,
            ]);

            // 更新审批单状态
            if ($action === 'reject') {
                // 拒绝：直接结束流程
                $approvalOrder->status = ApprovalOrder::STATUS_REJECTED;
                $approvalOrder->current_nodes = [];
                $businessTrip->status = BusinessTrip::STATUS_REJECTED;
            } else {
                // 同意：检查是否还有后续节点（简化版：直接通过）
                $approvalOrder->status = ApprovalOrder::STATUS_APPROVED;
                $approvalOrder->current_nodes = [];
                $businessTrip->status = BusinessTrip::STATUS_APPROVED;
            }

            $approvalOrder->save();
            $businessTrip->save();

            return $businessTrip->fresh(['itineraries', 'approvalOrder']);
        });
    }
}