package com.tourguide.modules.finance.service;

import com.tourguide.common.exception.BusinessException;
import com.tourguide.modules.finance.dto.WithdrawalResponse;
import com.tourguide.modules.finance.entity.GuideWithdrawal;
import com.tourguide.modules.finance.mapper.GuideWithdrawalMapper;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.StringUtils;

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.concurrent.ThreadLocalRandom;

/** 管理提现资金流程的本地事务状态，不在数据库事务中调用外部资金接口。 */
@Service
public class GuideWithdrawalStateService {
    static final String PENDING = "PENDING";
    static final String TRANSFERRING = "TRANSFERRING";
    static final String TRANSFERRED = "TRANSFERRED";
    static final String PROCESSING = "PROCESSING";
    static final String APPROVED = "APPROVED";
    static final String REJECTED = "REJECTED";

    private static final DateTimeFormatter DATE_FORMAT = DateTimeFormatter.ofPattern("yyyyMMdd");
    private static final DateTimeFormatter SEQ_TIME_FORMAT = DateTimeFormatter.ofPattern("yyyyMMddHHmmssSSS");

    private final GuideWithdrawalMapper withdrawalMapper;
    private final GuideWithdrawableBalanceService balanceService;

    public GuideWithdrawalStateService(GuideWithdrawalMapper withdrawalMapper,
                                       GuideWithdrawableBalanceService balanceService) {
        this.withdrawalMapper = withdrawalMapper;
        this.balanceService = balanceService;
    }

    @Transactional
    public WithdrawalResponse reject(Long id, String remark, String processor) {
        GuideWithdrawal withdrawal = requireForUpdate(id);
        if (!PENDING.equals(withdrawal.getStatus())) throw new BusinessException(409, "提现申请已处理");
        if (!StringUtils.hasText(remark)) throw new BusinessException(400, "驳回提现时请填写处理备注");
        balanceService.credit(withdrawal.getGuideId(), withdrawal.getAmount());
        withdrawal.setStatus(REJECTED);
        withdrawal.setAuditRemark(remark.trim());
        withdrawal.setProcessor(processor);
        withdrawal.setProcessedAt(LocalDateTime.now());
        update(withdrawal);
        return new WithdrawalResponse(withdrawal);
    }

    @Transactional
    public GuideWithdrawal prepareTransfer(Long id, String remark, String processor) {
        GuideWithdrawal withdrawal = requireForUpdate(id);
        if (!PENDING.equals(withdrawal.getStatus())) throw new BusinessException(409, "提现申请已处理");
        LocalDateTime now = LocalDateTime.now();
        withdrawal.setStatus(TRANSFERRING);
        withdrawal.setTransferReqSeqId(sequence("TF"));
        withdrawal.setTransferReqDate(now.format(DATE_FORMAT));
        withdrawal.setTransferHfSeqId(null);
        withdrawal.setPayoutMessage("等待主账户划账");
        withdrawal.setAuditRemark(StringUtils.hasText(remark) ? remark.trim() : null);
        withdrawal.setProcessor(processor);
        withdrawal.setProcessedAt(now);
        update(withdrawal);
        return withdrawal;
    }

    @Transactional
    public GuideWithdrawal markTransferred(Long id, String hfSeqId) {
        GuideWithdrawal withdrawal = requireForUpdate(id);
        if (!TRANSFERRING.equals(withdrawal.getStatus())) return withdrawal;
        withdrawal.setStatus(TRANSFERRED);
        withdrawal.setTransferHfSeqId(hfSeqId);
        withdrawal.setTransferredAt(LocalDateTime.now());
        withdrawal.setPayoutMessage("主账户划账成功，等待发起取现");
        update(withdrawal);
        return withdrawal;
    }

    @Transactional
    public GuideWithdrawal markTransferPending(Long id, String hfSeqId, String message) {
        GuideWithdrawal withdrawal = requireForUpdate(id);
        if (!TRANSFERRING.equals(withdrawal.getStatus())) return withdrawal;
        if (StringUtils.hasText(hfSeqId)) withdrawal.setTransferHfSeqId(hfSeqId);
        withdrawal.setPayoutMessage(limit(message));
        update(withdrawal);
        return withdrawal;
    }

    @Transactional
    public GuideWithdrawal markTransferFailed(Long id, String message) {
        GuideWithdrawal withdrawal = requireForUpdate(id);
        if (!TRANSFERRING.equals(withdrawal.getStatus())) return withdrawal;
        withdrawal.setStatus(PENDING);
        withdrawal.setPayoutMessage(limit(message));
        update(withdrawal);
        return withdrawal;
    }

    @Transactional
    public GuideWithdrawal prepareCash(Long id) {
        GuideWithdrawal withdrawal = requireForUpdate(id);
        if (!TRANSFERRED.equals(withdrawal.getStatus())) return null;
        LocalDateTime now = LocalDateTime.now();
        withdrawal.setStatus(PROCESSING);
        withdrawal.setCashReqSeqId(sequence("CW"));
        withdrawal.setCashReqDate(now.format(DATE_FORMAT));
        withdrawal.setCashHfSeqId(null);
        withdrawal.setPayoutMessage("已发起导游账户取现");
        update(withdrawal);
        return withdrawal;
    }

    @Transactional
    public GuideWithdrawal resumeCashQuery(Long id) {
        GuideWithdrawal withdrawal = requireForUpdate(id);
        if (!TRANSFERRED.equals(withdrawal.getStatus())
                || !StringUtils.hasText(withdrawal.getCashReqSeqId())
                || !StringUtils.hasText(withdrawal.getCashReqDate())) {
            return null;
        }
        withdrawal.setStatus(PROCESSING);
        withdrawal.setPayoutMessage("检测到原取现流水，等待查询最终状态");
        update(withdrawal);
        return withdrawal;
    }

    @Transactional
    public GuideWithdrawal markCashPending(Long id, String hfSeqId, String message) {
        GuideWithdrawal withdrawal = requireForUpdate(id);
        if (!PROCESSING.equals(withdrawal.getStatus())) return withdrawal;
        if (StringUtils.hasText(hfSeqId)) withdrawal.setCashHfSeqId(hfSeqId);
        withdrawal.setPayoutMessage(limit(message));
        update(withdrawal);
        return withdrawal;
    }

    @Transactional
    public GuideWithdrawal markCashRetry(Long id, String message) {
        GuideWithdrawal withdrawal = requireForUpdate(id);
        if (!PROCESSING.equals(withdrawal.getStatus())) return withdrawal;
        LocalDateTime now = LocalDateTime.now();
        String retryMessage = limit(message);
        if (withdrawalMapper.resetCashForRetry(id, retryMessage, now, now) != 1) {
            throw new BusinessException(500, "提现状态更新失败");
        }
        withdrawal.setStatus(TRANSFERRED);
        withdrawal.setCashReqSeqId(null);
        withdrawal.setCashReqDate(null);
        withdrawal.setCashHfSeqId(null);
        withdrawal.setPayoutMessage(retryMessage);
        withdrawal.setProcessedAt(now);
        withdrawal.setUpdatedAt(now);
        return withdrawal;
    }

    @Transactional
    public GuideWithdrawal markApproved(Long id, String hfSeqId) {
        GuideWithdrawal withdrawal = requireForUpdate(id);
        if (!PROCESSING.equals(withdrawal.getStatus())) return withdrawal;
        withdrawal.setStatus(APPROVED);
        if (StringUtils.hasText(hfSeqId)) withdrawal.setCashHfSeqId(hfSeqId);
        withdrawal.setPayoutMessage("取现到账成功");
        withdrawal.setProcessedAt(LocalDateTime.now());
        update(withdrawal);
        return withdrawal;
    }

    public GuideWithdrawal find(Long id) {
        GuideWithdrawal withdrawal = withdrawalMapper.selectById(id);
        if (withdrawal == null) throw new BusinessException(404, "提现申请不存在");
        return withdrawal;
    }

    private GuideWithdrawal requireForUpdate(Long id) {
        GuideWithdrawal withdrawal = withdrawalMapper.selectForUpdate(id);
        if (withdrawal == null) throw new BusinessException(404, "提现申请不存在");
        return withdrawal;
    }

    private void update(GuideWithdrawal withdrawal) {
        withdrawal.setUpdatedAt(LocalDateTime.now());
        if (withdrawalMapper.updateById(withdrawal) != 1) {
            throw new BusinessException(500, "提现状态更新失败");
        }
    }

    private String sequence(String prefix) {
        return prefix + LocalDateTime.now().format(SEQ_TIME_FORMAT)
                + String.format("%04d", ThreadLocalRandom.current().nextInt(10000));
    }

    private String limit(String message) {
        if (!StringUtils.hasText(message)) return "斗拱资金处理结果待确认";
        String value = message.trim();
        return value.length() <= 255 ? value : value.substring(0, 255);
    }
}