<?php
namespace App\Services\Exam;

use App\Models\ExamTopicModel;
use App\Services\BaseService;
use Illuminate\Support\Facades\DB;

/**
 * 题目管理-服务类
 * Class TopicService
 */
class TopicService extends BaseService
{
    protected static $instance = null;
    protected $model = null;

    public function __construct()
    {
        $this->model = new ExamTopicModel();
    }

    public static function make()
    {
        if (!self::$instance) {
            self::$instance = new TopicService();
        }
        return self::$instance;
    }

    public function customList($param, $pageSize = 15)
    {
        $query = $this->model->where('mark', 1);

        if (!empty($param['paper_id'])) {
            $query->where('paper_id', $param['paper_id']);
        }

        if (!empty($param['keyword'])) {
            $query->where(function ($q) use ($param) {
                $q->where('id', $param['keyword'])
                    ->orWhere('topic_name', 'like', "%{$param['keyword']}%");
            });
        }

        $list = $query->orderBy('sort', 'desc')->paginate($pageSize > 0 ? $pageSize : 9999999);
        $list = $list ? $list->toArray() : [];
        // 要处理的字段
        $fields = ['poster', 'topic_analysis', 'topic_name'];

        $items = isset($list['data']) ? $list['data'] : [];

        foreach ($items as &$item) {
            // 1-图片 2-文字
            if ($item['answer_type'] == 1 && in_array($item['topic_type'], ['填空题', '简单题'])) {
                $fields[] = 'correct_answer';
            }

            if (!empty($item['show_type']) && (int) $item['show_type'] === 2) {
                // 图片型 → 转为完整图片路径（支持多图）
                foreach ($fields as $field) {
                    if (!empty($item[$field])) {
                        $item[$field] = format_image_field($item[$field]);
                    }
                }
            } else {
                // 文本型 → 保持原样（如果你想裁剪空格可以加 trim）
                foreach ($fields as $field) {
                    if (!empty($item[$field])) {
                        $item[$field] = trim($item[$field]);
                    }
                }
            }
        }
        return [
            'pageSize' => $pageSize,
            'total' => isset($list['total']) ? $list['total'] : 0,
            'list' => $items
        ];
    }

    /**
     * 排序更新
     * @param array $param
     *   - paper_id
     *   - sort_data = [{id:xx, sort:xx}, ...]
     * @return array
     */
    public function sort($param)
    {
        $paperId = $param['paper_id'] ?? 0;
        $sortData = $param['sort_data'] ?? [];

        if (empty($paperId) || empty($sortData)) {
            return message("参数错误", false);
        }

        DB::beginTransaction();
        try {
            // 先更新前端传来的顺序
            foreach ($sortData as $item) {
                $this->model
                    ->where('id', $item['id'])
                    ->where('paper_id', $paperId)
                    ->update([
                        'sort' => $item['sort'],
                        'update_time' => time()
                    ]);
            }

            // 再统一重新编号，保证唯一性 + 倒序
            $topics = $this->model
                ->where('paper_id', $paperId)
                ->orderByDesc('sort')
                ->get();

            $newSort = count($topics);
            foreach ($topics as $topic) {
                $this->model
                    ->where('id', $topic->id)
                    ->update(['sort' => $newSort--]);
            }

            DB::commit();
            return message("排序更新成功", true);
        } catch (\Exception $e) {
            DB::rollBack();
            return message("排序更新失败：" . $e->getMessage(), false);
        }
    }
    /**
     * 编辑或新增视频集
     */
    public function edit()
    {
        $data = request()->all();

        // 定义需要处理的字段
        $fields = ['poster', 'topic_analysis', 'topic_name', 'correct_answer'];

        foreach ($fields as $field) {
            if (!empty($data[$field])) {
                // 如果 show_type == 2 → 处理为图片路径
                if (!empty($data['show_type']) && (int) $data['show_type'] === 2) {
                    if (is_array($data[$field])) {
                        $data[$field] = array_map(function ($img) {
                            return get_image_path(trim($img));
                        }, $data[$field]);
                        $data[$field] = implode(',', $data[$field]); // 多图用逗号拼接
                    } else {
                        $data[$field] = get_image_path(trim($data[$field]));
                    }
                } else {
                    // show_type != 2 → 文本，直接 trim
                    if (is_array($data[$field])) {
                        $data[$field] = implode(',', array_map('trim', $data[$field]));
                    } else {
                        $data[$field] = trim($data[$field]);
                    }
                }
            }
        }

        $id = $data['id'] ?? 0;

        // 默认字段处理
        $data['update_time'] = time();
        if (!$id) {
            $data['create_time'] = time();
        }

        return parent::edit($data); // 调用父类的 edit 方法
    }

}