'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');
const moment = require('moment');

//
class GroupService extends CrudService {
  constructor(ctx) {
    super(ctx, 'group');
    this.model = this.ctx.model.Group.Group;
    this.goodsModel = this.ctx.model.Shop.Goods;
    this.goodsSpecModel = this.ctx.model.Shop.GoodsSpec;
  }

  /**
   * 生成团
   * @param {Object} orderDetail 订单详情数据
   * @param {Transaction} tran 数据库事务实例
   */
  async create(orderDetail, tran) {
    const { goods: goodsInfo, customer, shop } = orderDetail;
    const goods_id = _.get(goodsInfo, 'goods._id');
    const goods = await this.goodsModel.findById(goods_id);
    const goodsSpec_id = _.get(goodsInfo, '_id');
    const goodsSpec = await this.goodsSpecModel.findById(goodsSpec_id);
    const person_limit = _.get(goodsSpec, 'group_config.need_person');
    const leader = customer;
    const persons = [{ customer, status: '0', join_time: moment().format('YYYY-MM-DD HH:mm:ss') }];
    const obj = { shop, goods, goodsSpec, leader, persons, person_limit };
    const id = tran.insert('Group', obj);
    return id;
  }

  /**
   * 加入团
   * @param {String} customer 用户id
   * @param {String} group_id 团id
   * @param {Transaction} tran 数据库事务实例
   */
  async join(customer, group_id, tran) {
    const result = await this.checkGroupCanJoin({ id: group_id });
    if (!result.result) throw new BusinessError(ErrorCode.DATA_INVALID, result.msg);
    const data = await this.model.findById(group_id);
    if (!data) throw new BusinessError(ErrorCode.DATA_NOT_EXIST, '未找到团信息');
    const { persons = [], person_limit } = data;
    const nps = JSON.parse(JSON.stringify(persons));
    nps.push({ customer, status: '0', join_time: moment().format('YYYY-MM-DD HH:mm:ss') });
    const updateData = { persons: nps };
    if (person_limit <= nps.length) updateData.status = '1';
    tran.update('Group', group_id, updateData);
  }

  // 检查是否可以加入团
  async checkGroupCanJoin({ id }) {
    const data = await this.model.findById(id);
    if (!data) throw new BusinessError(ErrorCode.DATA_NOT_EXIST, '未找到团数据');
    const { person_limit, persons = [], status } = data;
    if (status === '1') return { result: false, msg: '当前团已结束' };
    else if (status === '-1') return { result: false, msg: '当前团已关闭' };
    // 为0是正常的团员
    const realPersons = persons.filter(f => f.status === '0');
    if (realPersons.length < person_limit) return { result: true };
    return { result: false, msg: '当前参团人数已足够' };
  }

  /**
   * 团购退货(订单取消&售后退款/退货)
   * @param {Object} params 参数
   * @param params.group 团id
   * @param params.customer 用户id
   * @param tran
   */
  async refund({ group, customer }, tran) {
    const groupData = await this.model.findById(group);
    if (!groupData) throw new BusinessError(ErrorCode.DATA_NOT_EXIST, '未找到拼团数据');
    const { persons, leader } = groupData;
    const newPersons = JSON.parse(JSON.stringify(persons));
    const findPersonCondition = (c1, c2) => c1 === c2;
    const p = newPersons.find(f => findPersonCondition(f.customer, customer));
    if (!p) throw new BusinessError(ErrorCode.DATA_NOT_EXIST, '未找到要退团的用户');
    const i = newPersons.findIndex(f => findPersonCondition(f.customer, customer));
    p.status = '1';
    newPersons[i] = p;
    const updateData = { newPersons };
    // 团长退团了,根据入团时间降序,顺位成为团长
    if (leader === customer) {
      let newLeader;
      const orderList = _.orderBy(newPersons, [ 'status', 'join_time' ], [ 'asc', 'asc' ]);
      const head = _.head(orderList);
      if (head && head.status === '0') {
        newLeader = _.get(head, 'customer');
        updateData.leader = newLeader;
      }
    }
    tran.update('Group', group, updateData);
  }
}

module.exports = GroupService;