feat: complete finance and overseas receiving workflow

order/src/main/java/com/baiyue/order/client/FinanceWalletClient.java

@@ -0,0 +1,23 @@
+package com.baiyue.order.client;
+
+import com.baiyue.common.core.api.ApiResponse;
+import org.springframework.cloud.openfeign.FeignClient;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestHeader;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+
+@FeignClient(name = "finance-service", contextId = "orderFinanceWalletClient",
+    url = "${baiyue.clients.finance.url:}", path = "/internal/finance/v1/wallet")
+public interface FinanceWalletClient {
+    @GetMapping("/accounts/{customerId}")
+    ApiResponse<WalletAccount> account(
+        @RequestHeader("X-Internal-Service-Token") String internalToken,
+        @PathVariable("customerId") long customerId);
+
+    record WalletAccount(BigDecimal actualBalance, BigDecimal availableBalance,
+                         BigDecimal creditLimit, BigDecimal availableCredit,
+                         LocalDate creditExpiresOn, boolean creditActive) { }
+}

order/src/main/java/com/baiyue/order/service/OrderEligibilityGuard.java

@@ -3,14 +3,18 @@ package com.baiyue.order.service;
 import com.baiyue.common.core.api.ResultCode;
 import com.baiyue.common.core.exception.BizException;
 import com.baiyue.order.client.TenantEligibilityClient;
+import com.baiyue.order.client.FinanceWalletClient;
 import feign.FeignException;
 import jakarta.annotation.Resource;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Service;
 
+import java.math.BigDecimal;
+
 @Service
 public class OrderEligibilityGuard {
     @Resource private TenantEligibilityClient client;
+    @Resource private FinanceWalletClient financeWalletClient;
     @Value("${baiyue.security.internal-service-token}") private String internalToken;
 
     public void requireApproved(long tenantId) {
@@ -32,6 +36,7 @@ public class OrderEligibilityGuard {
                 throw new BizException(ResultCode.FORBIDDEN,
                         response.data().reason() == null ? "Enterprise review approval is required" : response.data().reason());
             }
+            requireNonNegativeActualBalance(tenantId);
         } catch (FeignException exception) {
             throw new BizException(ResultCode.SERVICE_UNAVAILABLE, "IAM eligibility service is unavailable");
         } catch (BizException exception) {
@@ -41,4 +46,23 @@ public class OrderEligibilityGuard {
             throw new BizException(ResultCode.SERVICE_UNAVAILABLE, "IAM 下单资格响应无效");
         }
     }
+
+    private void requireNonNegativeActualBalance(long tenantId) {
+        try {
+            var response = financeWalletClient.account(internalToken, tenantId);
+            if (response == null || !response.successful() || response.data() == null
+                || response.data().actualBalance() == null) {
+                throw new BizException(ResultCode.SERVICE_UNAVAILABLE, "Unable to verify customer account balance");
+            }
+            if (response.data().actualBalance().compareTo(BigDecimal.ZERO) < 0) {
+                throw new BizException(ResultCode.FORBIDDEN, "账户实际余额为负，请充值后再下单");
+            }
+        } catch (FeignException exception) {
+            throw new BizException(ResultCode.SERVICE_UNAVAILABLE, "Finance account service is unavailable");
+        } catch (BizException exception) {
+            throw exception;
+        } catch (RuntimeException exception) {
+            throw new BizException(ResultCode.SERVICE_UNAVAILABLE, "Finance account response is invalid");
+        }
+    }
 }