package com.pollex.pam.service;

import com.pollex.pam.config.ApplicationProperties;
import com.pollex.pam.domain.Appointment;
import com.pollex.pam.domain.AppointmentExpiringNotifyRecord;
import com.pollex.pam.domain.Consultant;
import com.pollex.pam.enums.AppointmentStatusEnum;
import com.pollex.pam.enums.ContactStatusEnum;
import com.pollex.pam.repository.AppointmentExpiringNotifyRecordRepository;
import com.pollex.pam.repository.AppointmentRepository;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;
import org.thymeleaf.context.Context;
import org.thymeleaf.spring5.SpringTemplateEngine;

import java.time.Instant;
import java.time.LocalDate;
import java.time.ZoneId;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.stream.Collectors;

@Service
public class ScheduleTaskService {

    /**
     * 電話及email在建立預約單(T)後的N天視為未處理預約單
     * 目前N皆暫定為2
     */
    private static final int APPOINTMENT_PENDING_PHONE_INTERVAL = 2;
    private static final int APPOINTMENT_PENDING_EMAIL_INTERVAL = 2;

    /**
     * 電話及email在建立預約單(T)後的N天會被視為未處理預約單，當天批次會發送提醒給顧問
     * 而在後一天(T+N+1)，就會發送批次給客戶告知 該顧問可能忙碌無法處理，是否需要取消
     */
    private static final int APPOINTMENT_EXPIRING_PHONE_INTERVAL = APPOINTMENT_PENDING_PHONE_INTERVAL + 1;
    private static final int APPOINTMENT_EXPIRING_EMAIL_INTERVAL = APPOINTMENT_PENDING_EMAIL_INTERVAL + 1;

    /**
     * 通知客戶的次數限制
     */
    private static final int SEND_EXPIRING_NOTIFY_LIMIT = 1;

    private static final String NOT_CONTACTED_NOTIFY_SUBJECT = "預約單未進行聯繫通知";
    private static final Logger log = LoggerFactory.getLogger(ScheduleTaskService.class);

    @Autowired
    ConsultantService consultantService;

    @Autowired
    AppointmentService appointmentService;

    @Autowired
    AppointmentRepository appointmentRepository;

    @Autowired
    SendMsgService sendMsgService;

    @Autowired
    SpringTemplateEngine springTemplateEngine;

    @Autowired
    ApplicationProperties applicationProperties;

    @Autowired
    AppointmentExpiringNotifyRecordRepository appointmentExpiringNotifyRecordRepository;

    @Scheduled(cron = "0 30 8 * * *")
    public void sendAppointmentPendingNotifyToConsultant() {
        log.info("Starting send appointment pending notify to consultant");

        Map<String, List<Appointment>> consultantWithPendingAppointments =
            appointmentRepository.findAllByCommunicateStatusAndStatus(ContactStatusEnum.RESERVED, AppointmentStatusEnum.AVAILABLE)
                .stream()
                .filter(appointment -> isAppointmentInInterval(appointment, APPOINTMENT_PENDING_PHONE_INTERVAL, APPOINTMENT_PENDING_EMAIL_INTERVAL))
                .collect(Collectors.groupingBy(Appointment::getAgentNo));

        consultantWithPendingAppointments.forEach((agentNo, pendingAppointments) -> {
            int pendingAppointmentsSum = pendingAppointments.size();
            Consultant consultant = consultantService.findByAgentNo(agentNo);
            String consultantPhoneNumber = consultant.getPhoneNumber();
            String consultantEmail = consultant.getEmail();
            String emailContent = getAppointmentPendingNotifyEmailContent(pendingAppointmentsSum);

            sendMsgService.sendMsgBySMS(consultantPhoneNumber, String.format("您有%s則預約單未進行聯繫，請盡速處理", pendingAppointmentsSum));
            sendMsgService.sendMsgByEmail(consultantEmail, NOT_CONTACTED_NOTIFY_SUBJECT, emailContent, true);
        });

        log.info("Sending appointment pending notify to consultant finish");
    }

    @Scheduled(cron = "0 30 8 * * *")
    public void sendAppointmentExpiringNotifyToCustomer() {
        log.info("Starting send appointment expiring notify to customer");

        List<Appointment> allByCommunicateStatus =
            appointmentRepository.findAllByCommunicateStatusAndStatus(ContactStatusEnum.RESERVED, AppointmentStatusEnum.AVAILABLE)
                .stream()
                .filter(appointment -> isAppointmentInInterval(appointment, APPOINTMENT_EXPIRING_PHONE_INTERVAL, APPOINTMENT_EXPIRING_EMAIL_INTERVAL))
                .filter(this::isAppointmentNotifyNotOnLimit)
                .collect(Collectors.toList());

        allByCommunicateStatus.forEach(appointment -> {
            Consultant consultant = consultantService.findByAgentNo(appointment.getAgentNo());
            Optional<String> optionalPhone = Optional.ofNullable(appointment.getPhone()).filter(StringUtils::hasText);
            Optional<String> optionalEmail = Optional.ofNullable(appointment.getEmail()).filter(StringUtils::hasText);

            optionalPhone.ifPresent(phone ->
                sendMsgService.sendMsgBySMS(phone, String.format("很抱歉！您預約%s顧問正忙碌中，請您取消預約並改選其他顧問，請點擊網址：%s"
                    , consultant.getName(), getAppointmentUrl(appointment.getId())))
            );
            optionalEmail.ifPresent(email ->
                sendMsgService.sendMsgByEmail(email, NOT_CONTACTED_NOTIFY_SUBJECT, getAppointmentExpiringNotifyEmail(consultant.getName(), getAppointmentUrl(appointment.getId())), true)
            );

            AppointmentExpiringNotifyRecord record = new AppointmentExpiringNotifyRecord();
            record.setAppointmentId(appointment.getId());
            record.setSendTime(Instant.now());

            appointmentExpiringNotifyRecordRepository.save(record);
        });

        log.info("Sending appointment expiring notify to customer finish");
    }

    private boolean isAppointmentInInterval(Appointment appointment, int phoneInterval, int emailInterval) {
        final boolean isHavePhone = StringUtils.hasText(appointment.getPhone());
        final boolean isHaveEmail = StringUtils.hasText(appointment.getEmail());

        LocalDate appointmentDate = appointment.getAppointmentDate().atZone(ZoneId.systemDefault()).toLocalDate();
        LocalDate nowDate = Instant.now().atZone(ZoneId.systemDefault()).toLocalDate();
        long intervalDays = nowDate.toEpochDay() - appointmentDate.toEpochDay();

        final boolean isAppointmentExpiringByPhone = isHavePhone && intervalDays >= phoneInterval;
        final boolean isAppointmentExpiringByEmail = isHaveEmail && intervalDays >= emailInterval;

        return isAppointmentExpiringByPhone || isAppointmentExpiringByEmail;
    }

    private boolean isAppointmentNotifyNotOnLimit(Appointment appointment) {
        int sendNotifyToCustomerRecordSum =
            appointmentExpiringNotifyRecordRepository.findAllByAppointmentId(appointment.getId()).size();

        return sendNotifyToCustomerRecordSum < SEND_EXPIRING_NOTIFY_LIMIT;
    }

    private String getAppointmentUrl(Long appointmentId) {
        return applicationProperties.getFrontEndDomain() + "?notContactAppointmentId=" + appointmentId;
    }

    private String getAppointmentPendingNotifyEmailContent(int sum) {
        Context context = new Context();
        context.setVariable("pendingAppointmentSum", sum);
        return springTemplateEngine.process("mail/appointmentPendingNotifyEmail", context);
    }

    private String getAppointmentExpiringNotifyEmail(String consultantName, String notifyUrl) {
        Context context = new Context();
        context.setVariable("consultantName", consultantName);
        context.setVariable("notifyUrl", notifyUrl);
        return springTemplateEngine.process("mail/appointmentExpiringNotifyEmail", context);
    }
}