const dayjs = require('dayjs');

module.exports = async (item, db) => {
  switch (item.type) {
    case 'getHlwSchedule':
      return getHlwSchedule(item, db);
    case 'saveHlwSchedule':
      return saveHlwSchedule(item, db);
    case 'setTodayScheduledPeopleOnline':
      return setTodayScheduledPeopleOnline(db);
  }
};

function getDate(value) {
  if (typeof value !== 'string' || !/^\d{4}-\d{2}-\d{2}$/.test(value)) return '';
  const parsed = dayjs(value);
  return parsed.isValid() && parsed.format('YYYY-MM-DD') === value ? value : '';
}

function getMonth(value) {
  if (typeof value !== 'string' || !/^\d{4}-\d{2}$/.test(value)) return '';
  const parsed = dayjs(`${value}-01`);
  return parsed.isValid() && parsed.format('YYYY-MM') === value ? value : '';
}

async function getHlwSchedule({ corpId, month }, db) {
  const normalizedCorpId = typeof corpId === 'string' ? corpId.trim() : '';
  const normalizedMonth = getMonth(month);
  if (!normalizedCorpId || !normalizedMonth) return { success: false, message: '机构或月份参数错误' };

  try {
    const startDate = `${normalizedMonth}-01`;
    const endDate = dayjs(startDate).add(1, 'month').format('YYYY-MM-DD');
    const data = await db.collection('hlw-schedule')
      .find({ corpId: normalizedCorpId, date: { $gte: startDate, $lt: endDate } }, { projection: { _id: 0 } })
      .sort({ date: 1 })
      .toArray();
    return { success: true, message: '查询成功', data };
  } catch (error) {
    return { success: false, message: error.message || '查询排班失败' };
  }
}

async function saveHlwSchedule({ corpId, date, doctorNos = [], pharmacistNos = [], operator, operatorId }, db) {
  const normalizedCorpId = typeof corpId === 'string' ? corpId.trim() : '';
  const normalizedDate = getDate(date);
  if (!normalizedCorpId || !normalizedDate) return { success: false, message: '机构或日期参数错误' };
  if (dayjs(normalizedDate).isBefore(dayjs(), 'day')) return { success: false, message: '过去日期的排班不可编辑' };

  const normalizeNos = values => [...new Set((Array.isArray(values) ? values : [])
    .filter(value => typeof value === 'string' && value.trim())
    .map(value => value.trim()))];
  const normalizedDoctorNos = normalizeNos(doctorNos);
  const normalizedPharmacistNos = normalizeNos(pharmacistNos);

  try {
    const personnel = await db.collection('hlw-doctor').find(
      {
        corpId: normalizedCorpId,
        doctorNo: { $in: [...normalizedDoctorNos, ...normalizedPharmacistNos] },
        job: { $in: ['doctor', 'pharmacist'] }
      },
      { projection: { doctorNo: 1, doctorName: 1, job: 1 } }
    ).toArray();
    const peopleByNo = new Map(personnel.map(person => [person.doctorNo, person]));
    const toPeople = (nos, job) => {
      const people = nos.map(no => peopleByNo.get(no));
      return people.length === nos.length && people.every(person => person && person.job === job)
        ? people.map(({ doctorNo, doctorName }) => ({ doctorNo, doctorName }))
        : null;
    };
    const doctors = toPeople(normalizedDoctorNos, 'doctor');
    const pharmacists = toPeople(normalizedPharmacistNos, 'pharmacist');
    if (!doctors || !pharmacists) return { success: false, message: '排班人员不存在或岗位不匹配' };

    await db.collection('hlw-schedule').updateOne(
      { corpId: normalizedCorpId, date: normalizedDate },
      {
        $set: {
          doctors,
          pharmacists,
          updater: typeof operator === 'string' ? operator : '',
          updaterId: typeof operatorId === 'string' ? operatorId : '',
          updateTime: Date.now()
        },
        $setOnInsert: { corpId: normalizedCorpId, date: normalizedDate, createTime: Date.now() }
      },
      { upsert: true }
    );
    if (normalizedDate === dayjs().format('YYYY-MM-DD')) {
      const onlineResult = await setTodayScheduledPeopleOnline(db);
      if (!onlineResult.success) {
        return { success: false, message: `排班已保存，但设置当天排班人员在线失败：${onlineResult.message}` };
      }
    }
    return { success: true, message: '排班保存成功' };
  } catch (error) {
    return { success: false, message: error.message || '保存排班失败' };
  }
}

async function setTodayScheduledPeopleOnline(db) {
  const date = dayjs().format('YYYY-MM-DD');
  try {
    const schedules = await db.collection('hlw-schedule')
      .find({ date }, { projection: { corpId: 1, doctors: 1, pharmacists: 1 } })
      .toArray();
    const peopleByCorp = new Map();
    const addPeople = (corpId, people, job) => {
      if (typeof corpId !== 'string' || !corpId.trim()) return;
      if (!peopleByCorp.has(corpId)) {
        peopleByCorp.set(corpId, { doctors: new Set(), pharmacists: new Set() });
      }
      const target = job === 'doctor'
        ? peopleByCorp.get(corpId).doctors
        : peopleByCorp.get(corpId).pharmacists;
      (Array.isArray(people) ? people : []).forEach((person) => {
        if (typeof person?.doctorNo === 'string' && person.doctorNo.trim()) {
          target.add(person.doctorNo.trim());
        }
      });
    };

    schedules.forEach(({ corpId, doctors, pharmacists }) => {
      addPeople(corpId, doctors, 'doctor');
      addPeople(corpId, pharmacists, 'pharmacist');
    });

    const updateTime = Date.now();
    const operations = [];
    for (const [corpId, { doctors, pharmacists }] of peopleByCorp) {
      if (doctors.size > 0) {
        operations.push({
          updateMany: {
            filter: { corpId, doctorNo: { $in: [...doctors] }, job: 'doctor' },
            update: { $set: { onlineStatus: 'online', offlineTime: null, updateTime } }
          }
        });
      }
      if (pharmacists.size > 0) {
        operations.push({
          updateMany: {
            filter: { corpId, doctorNo: { $in: [...pharmacists] }, job: 'pharmacist' },
            update: { $set: { onlineStatus: 'online', offlineTime: null, updateTime } }
          }
        });
      }
    }

    if (operations.length === 0) {
      return { success: true, message: '当天无排班人员', data: { date, matchedCount: 0, modifiedCount: 0 } };
    }

    const result = await db.collection('hlw-doctor').bulkWrite(operations);
    return {
      success: true,
      message: '当天排班人员已上线',
      data: { date, matchedCount: result.matchedCount, modifiedCount: result.modifiedCount }
    };
  } catch (error) {
    return { success: false, message: error.message || '设置当天排班人员在线失败' };
  }
}