Javascript -遍历约会数组，查找下一个可用项

Question

给定约会天数，我尝试遍历一组约会(它们是包含startDate和endDate的对象)，找出最快出现的x天，但没有预约(pendingStartDate)。尝试使用moment，但我不确定这是不是正确的(或最优雅的)路线。注意:我不仅仅是解决在所有约会之后获得第一个开放日的问题，因为在现有约会之间可以有开放日。

import Moment from 'moment';
import { extendMoment } from 'moment-range';

const moment = extendMoment(Moment);

const determineStartDate = (daysNeeded, existingAppts) => {
  // this is about as far as I've gotten...
  pendingStartDate = moment();
  existingAppts.forEach((a) => {
    range = moment.range(moment(a.startDate), moment(a.endDate);
    console.log(range.contains(pendingStartDate));
  })

}

// just some dummy code to help explain
const daysNeeded = 2
const existingAppts = [
  { startDate: '2020-06-15', endDate: '2020-06-17' },
  { startDate: '2020-06-14', endDate: '2020-06-14' },
]
const pendingStartDate = determineStartDate(daysNeeded, existingAppts);

Answer 1

如果你不想这样做，不需要使用moment ..可以使用javascript Date()。

existingAppts.sort(function(a, b) {
  var aDate = new Date(a.endDate);
  var bDate = new Date(b.endDate);
  return (aDate - bDate);
});

daysNeeded = (daysNeeded > 0) ? daysNeeded - 1 : 0; 
var apptFound = false;
var apptStart;
var apptEnd;
for(var index = 0; index < (existingAppts.length - 1) && !apptFound; index++){
  apptStart = new Date(existingAppts[index].endDate);
  apptStart.setDate(apptStart.getDate() + 1);

  apptEnd = newDate();
  apptEnd.setDate(apptStart.getDate() + daysNeeded);

  var nextStart = newDate(existingAppts[index + 1].startDate);
  if(apptEnd < nextStart){
    apptFound = true;
  }
}
if(!apptFound){
  apptStart = newDate(existingAppts[existingAppts.length - 1].endDate);
  apptStart.setDate(apptStart.getDate() + 1);
  apptEnd = newDate();
  apptEnd.setDate(apptStart.getDate() + daysNeeded);
}
existingAppts.push({startDate: apptStart, endDate: apptEnd});

在您的determineStartDate函数中，首先按endDate对现有约会进行排序。然后循环你的约会..。新约会的潜在开始日期是当前约会结束后的一天。计算潜在的结束日期，并与列表中下一个约会的开始日期进行比较。如果有空间，则退出循环并将新约会设置到数组中。如果循环退出，但没有找到足够大的空位，则将约会安排在最后一次预约后的第二天(或客户希望的任何时候)。

Answer 2

function determineStartDate(daysNeeded, existingAppts) { 
  // sort your existing appointments
  const sortedAppointments = existingAppts.sort(function(a, b) {
    var aDate = new Date(a.endDate);
    var bDate = new Date(b.endDate);
    return (aDate - bDate);
  });

  // potentialStartDate, start from today
  let pStartDateInUTC = Date.now()
  for (let appointment of sortedAppointments) {
    const aStartDate = new Date(appointment['startDate'])
    const aEndDate = new Date(appointment['endDate'])

    // calculate potentialEndDate
    let pEndDate = new Date(pStartDateInUTC + (daysNeeded-1) * 24 * 60 * 60 * 1000)

    // if potentialEndDate is before the startDate 
    // of the current appointment,
    // it is a valid solution
    if (pEndDate < aStartDate) {
        // match found!
        break
    }

    // else, reset potential start date to 
    // day after current appointment's end date
    pStartDateInUTC = (new Date()).setDate(aEndDate.getDate() + 1)
  }

  return new Date(pStartDateInUTC)
}