package com.tourguide.modules.order.service;

import com.tourguide.common.huifu.RequestSeqUtil;
import com.tourguide.modules.order.domain.OrderStatus;
import com.tourguide.modules.order.domain.PaymentMethod;
import com.tourguide.modules.order.domain.RefundAmountCalculator;
import com.tourguide.modules.order.domain.RefundStatus;
import com.tourguide.modules.order.entity.TourOrder;
import com.tourguide.modules.order.entity.TourOrderRefund;
import com.tourguide.modules.order.mapper.TourOrderMapper;
import com.tourguide.modules.order.mapper.TourOrderRefundMapper;
import com.tourguide.modules.order.payment.PaymentRefundGateway;
import com.tourguide.modules.finance.service.GuideBalanceSettlementService;
import org.springframework.beans.factory.annotation.Autowired;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;

import java.math.BigDecimal;
import java.time.LocalDateTime;

@Service
public class OrderRefundService {
    private static final Logger log = LoggerFactory.getLogger(OrderRefundService.class);

    private final TourOrderMapper orderMapper;
    private final PaymentRefundGateway paymentRefundGateway;
    private final TourOrderRefundMapper refundMapper;
    private final GuideBalanceSettlementService balanceSettlementService;

    public OrderRefundService(TourOrderMapper orderMapper, PaymentRefundGateway paymentRefundGateway) {
        this(orderMapper, paymentRefundGateway, null, null);
    }

    public OrderRefundService(TourOrderMapper orderMapper, PaymentRefundGateway paymentRefundGateway,
                              TourOrderRefundMapper refundMapper) {
        this(orderMapper, paymentRefundGateway, refundMapper, null);
    }

    @Autowired
    public OrderRefundService(TourOrderMapper orderMapper, PaymentRefundGateway paymentRefundGateway,
                              TourOrderRefundMapper refundMapper,
                              GuideBalanceSettlementService balanceSettlementService) {
        this.orderMapper = orderMapper;
        this.paymentRefundGateway = paymentRefundGateway;
        this.refundMapper = refundMapper;
        this.balanceSettlementService = balanceSettlementService;
    }

    public boolean requestRefund(TourOrder order) {
        if (order == null) return false;
        BigDecimal refundAmount = RefundAmountCalculator.refundableAmount(order);
        return requestRefund(order, refundAmount);
    }

    public boolean requestRefund(TourOrder order, BigDecimal refundAmount) {
        if (order == null || order.getPaymentTime() == null) {
            return false;
        }
        if (RefundStatus.REFUNDED.matches(order.getRefundStatus())
                || OrderStatus.REFUNDED.matches(order.getStatus())) {
            return true;
        }
        if (RefundStatus.REFUNDING.matches(order.getRefundStatus())
                && StringUtils.hasText(order.getRefundOrderNo())) {
            return true;
        }
        if (refundAmount == null || refundAmount.compareTo(BigDecimal.ZERO) <= 0) {
            return false;
        }
        BigDecimal refundableAmount = RefundAmountCalculator.refundableAmount(order);
        if (refundAmount.compareTo(refundableAmount) > 0) {
            return false;
        }
        order.setRefundOrderNo(RequestSeqUtil.generateForBusiness("RF"));
        order.setRefundStatus(RefundStatus.REFUNDING.getCode());
        order.setRefundAmount(refundAmount);
        order.setRefundMethod(order.getPaymentMethod());
        TourOrderRefund refundRecord = createRefundRecord(order, refundAmount);
        if (PaymentMethod.TEMPORARY_BYPASS.matches(order.getPaymentMethod())) {
            if (order.getCancelledAt() == null) order.setCancelledAt(LocalDateTime.now());
            completeLocalRefund(order, refundAmount);
            LocalDateTime refundTime = LocalDateTime.now();
            order.setRefundTime(refundTime);
            // 明细状态描述当前这一笔退款；订单状态则描述累计退款进度。
            updateRefundRecord(refundRecord, RefundStatus.REFUNDED.getCode(), refundTime);
            orderMapper.updateById(order);
            return true;
        }
        orderMapper.updateById(order);
        try {
            String refundRequestNo = paymentRefundGateway.refund(order, refundAmount);
            if (!StringUtils.hasText(refundRequestNo)) {
                throw new IllegalStateException("Payment provider did not accept refund request");
            }
            if (!OrderStatus.CANCELLED.matches(order.getStatus())) {
                order.setStatus(OrderStatus.CANCELLED.getCode());
            }
            if (order.getCancelledAt() == null) order.setCancelledAt(LocalDateTime.now());
            orderMapper.updateById(order);
            return true;
        } catch (RuntimeException exception) {
            order.setRefundStatus(RefundStatus.REFUND_FAILED.getCode());
            updateRefundRecord(refundRecord, RefundStatus.REFUND_FAILED.getCode(), null);
            orderMapper.updateById(order);
            log.error("Order refund request failed, orderId={}, orderNo={}, refundOrderNo={}",
                    order.getId(), order.getOrderNo(), order.getRefundOrderNo(), exception);
            return false;
        }
    }

    private void completeLocalRefund(TourOrder order, BigDecimal refundAmount) {
        BigDecimal previousRefundedAmount = RefundAmountCalculator.refundedAmount(order);
        BigDecimal refundedAmount = previousRefundedAmount.add(refundAmount);
        order.setRefundedAmount(refundedAmount);
        if (refundedAmount.compareTo(RefundAmountCalculator.paidAmount(order)) >= 0) {
            order.setRefundStatus(RefundStatus.REFUNDED.getCode());
            order.setStatus(OrderStatus.REFUNDED.getCode());
        } else {
            order.setRefundStatus(RefundStatus.PARTIAL.getCode());
            order.setStatus(OrderStatus.CANCELLED.getCode());
        }
        reverseSettledEarning(order, previousRefundedAmount, refundedAmount);
    }

    private void reverseSettledEarning(TourOrder order, BigDecimal previousRefundedAmount,
                                       BigDecimal currentRefundedAmount) {
        if (balanceSettlementService != null) {
            balanceSettlementService.reverseRefund(order, previousRefundedAmount, currentRefundedAmount);
        }
    }

    private TourOrderRefund createRefundRecord(TourOrder order, BigDecimal refundAmount) {
        if (refundMapper == null || order.getId() == null) return null;
        TourOrderRefund refund = new TourOrderRefund();
        refund.setOrderId(order.getId());
        refund.setRefundOrderNo(order.getRefundOrderNo());
        refund.setRefundAmount(refundAmount);
        refund.setRefundStatus(RefundStatus.REFUNDING.getCode());
        refund.setRefundMethod(order.getRefundMethod());
        refundMapper.insert(refund);
        return refund;
    }

    private void updateRefundRecord(TourOrderRefund refund, String status, LocalDateTime refundTime) {
        if (refundMapper == null || refund == null) return;
        refund.setRefundStatus(status);
        refund.setRefundTime(refundTime);
        refundMapper.updateById(refund);
    }
}