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

//
class LessonStudentService extends CrudService {
  constructor(ctx) {
    super(ctx, 'lessonstudent');
    this.model = this.ctx.model.Business.LessonStudent;
  }

  async beforeCreate(body) {
    const { lesson_id, school_id, student_id } = body;
    // 检查是否已经有数据
    const data = await this.model.findOne({ lesson_id, school_id, student_id });
    // 数据已存在,检查是否是申请试听
    if (data) {
      const { is_try } = data;
      if (is_try === '0') throw new BusinessError(ErrorCode.DATA_EXISTED, '您已经报名');
    }
    // 数据不存在
    const { is_try } = body;
    // 检查是否使用试听名额
    if (is_try === '1') {
      const num = await this.model.count({ student_id, is_try: '1' });
      if (num > 0) throw new BusinessError(ErrorCode.SERVICE_FAULT, '您已使用过免费试听的机会');
    }
    return body;
  }
}

module.exports = LessonStudentService;