package com.baiyue.lastleg.wallet;

import com.baomidou.mybatisplus.core.toolkit.IdWorker;
import com.baiyue.common.event.EventEnvelope;
import com.baiyue.common.event.EventIdentifiers;
import com.baiyue.common.event.EventPayloadCanonicalizer;
import com.baiyue.common.event.EventPayloadHash;
import com.baiyue.common.event.EventTypes;
import com.baiyue.common.event.WalletCommandRequestedV1;
import com.baiyue.lastleg.entity.LastlegEventOutbox;
import com.baiyue.lastleg.mapper.LastlegEventOutboxMapper;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;

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

@Service
@RequiredArgsConstructor
public class WalletCommandOutboxService {
    private final LastlegEventOutboxMapper mapper;
    private final ObjectMapper objectMapper;

    public String publish(String operation, long customerId, String businessType, String businessNo,
                          BigDecimal amount, String remark, long aggregateVersion) {
        if ("REFUND".equals(operation)) throw new IllegalArgumentException("退款必须关联原扣款流水");
        return publishCommand(operation, customerId, businessType, businessNo, amount, remark, aggregateVersion, null);
    }

    public String publishRefund(long customerId, String businessType, String refundNo, BigDecimal amount,
                                String originalLedgerId, String remark, long aggregateVersion) {
        if (originalLedgerId == null || !originalLedgerId.matches("[1-9][0-9]*")) {
            throw new IllegalArgumentException("退款原扣款流水无效");
        }
        return publishCommand("REFUND", customerId, businessType, refundNo, amount, remark, aggregateVersion, originalLedgerId);
    }

    private String publishCommand(String operation, long customerId, String businessType, String businessNo,
                                  BigDecimal amount, String remark, long aggregateVersion, String originalLedgerId) {
        String eventKey = "WALLET_COMMAND:" + customerId + ':' + businessType + ':' + businessNo + ':' + operation + ':' + aggregateVersion;
        LastlegEventOutbox existing = mapper.findByEventKey(eventKey);
        if (existing != null) {
            try {
                EventEnvelope saved = objectMapper.readValue(existing.getPayloadJson(), EventEnvelope.class);
                WalletCommandRequestedV1 command = objectMapper.treeToValue(saved.payload(), WalletCommandRequestedV1.class);
                if (command.customerId() != customerId || !operation.equals(command.operation())
                    || !businessType.equals(command.businessType()) || !businessNo.equals(command.businessNo())
                    || !java.util.Objects.equals(remark, command.remark())
                    || !java.util.Objects.equals(originalLedgerId, command.originalLedgerId())
                    || (amount == null ? command.amount() != null : command.amount() == null || amount.compareTo(command.amount()) != 0)) {
                    throw new IllegalStateException("同一资金请求对应不同费用事实");
                }
                return saved.eventId();
            } catch (java.io.IOException exception) {
                throw new IllegalStateException("资金指令事件快照损坏", exception);
            }
        }
        String idempotencyKey = customerId + ":" + businessType + ':' + businessNo + ':' + operation + ':' + aggregateVersion;
        WalletCommandRequestedV1 value = new WalletCommandRequestedV1(operation, customerId, businessType,
            businessNo, amount, remark, idempotencyKey, Instant.now(), originalLedgerId);
        JsonNode payload = objectMapper.valueToTree(value);
        EventEnvelope envelope = new EventEnvelope(EventIdentifiers.newUuid(), EventTypes.WALLET_COMMAND_REQUESTED,
            WalletCommandRequestedV1.VERSION, Instant.now(),
            String.valueOf(customerId), businessType, businessNo, aggregateVersion, null,
            EventIdentifiers.newUuid(), eventKey, null, payload,
            EventPayloadHash.sha256(EventPayloadCanonicalizer.canonicalize(payload))).requireValid();
        LastlegEventOutbox row = new LastlegEventOutbox();
        row.setId(IdWorker.getId()); row.setCustomerId(String.valueOf(customerId));
        row.setAggregateType(businessType); row.setAggregateId(businessNo);
        row.setEventType(envelope.eventType()); row.setEventVersion(envelope.eventVersion());
        row.setEventKey(eventKey); row.setPayloadJson(json(envelope)); row.setStatus("PENDING");
        row.setRetryCount(0); row.setCreatedAt(LocalDateTime.now(ZoneOffset.UTC));
        mapper.insert(row);
        return envelope.eventId();
    }

    private String json(Object value) {
        try { return objectMapper.writeValueAsString(value); }
        catch (Exception exception) { throw new IllegalStateException("资金指令事件序列化失败", exception); }
    }
}