'use strict';


const assert = require('assert');
const _ = require('lodash');
const { ObjectId } = require('mongoose').Types;
const { CrudService } = require('naf-framework-mongoose/lib/service');
const { BusinessError, ErrorCode } = require('naf-core').Error;

class ClassService extends CrudService {
  constructor(ctx) {
    super(ctx, 'class');
    this.model = this.ctx.model.Class;
    this.stumodel = this.ctx.model.Student;
  }

  async divide(data) {
    const name = await data.classname;
    const number = await data.students.length;
    const type = await data.type;
    const termid = await data.termid;
    const batchid = await data.batchid;
    const classdata = { name, batchid, termid, number, type };
    // 根据班级名称查询班级是否已存在
    const newclass = await this.model.findOne({ name });
    // 如果已经存在抛出异常
    if (newclass) {
      throw new BusinessError(ErrorCode.DATA_EXIST, '班级名称已存在');
    }
    // 如果班级不存在则创建班级
    const newdata = await this.model.create(classdata);
    // 查询班级id
    const classid = newdata._id;
    // 遍历学生id
    for (const studentid of data.students) {
      // 根据学生id找到学生数据修改其中的class字段
      const student = await this.stumodel.findById(studentid);
      student.classid = classid;
      student.batchid = batchid;
      student.termid = termid;
      await student.save();
    }
  }
}

module.exports = ClassService;