fix

Service/Transaction/TransactionStatisticsService.cs

@@ -8,6 +8,11 @@ public interface ITransactionStatisticsService
 
     Task<MonthlyStatistics> GetMonthlyStatisticsAsync(int year, int month);
 
+    /// <summary>
+    /// 按日期范围获取汇总统计数据（新统一接口）
+    /// </summary>
+    Task<MonthlyStatistics> GetSummaryByRangeAsync(DateTime startDate, DateTime endDate);
+
     Task<List<CategoryStatistics>> GetCategoryStatisticsAsync(int year, int month, TransactionType type);
 
     /// <summary>
@@ -119,6 +124,44 @@ public class TransactionStatisticsService(
         return statistics;
     }
 
+    /// <summary>
+    /// 按日期范围获取汇总统计数据（新统一接口）
+    /// </summary>
+    public async Task<MonthlyStatistics> GetSummaryByRangeAsync(DateTime startDate, DateTime endDate)
+    {
+        var records = await transactionRepository.QueryAsync(
+            startDate: startDate,
+            endDate: endDate,
+            pageSize: int.MaxValue);
+
+        var statistics = new MonthlyStatistics
+        {
+            Year = startDate.Year,
+            Month = startDate.Month
+        };
+
+        foreach (var record in records)
+        {
+            var amount = Math.Abs(record.Amount);
+
+            if (record.Type == TransactionType.Expense)
+            {
+                statistics.TotalExpense += amount;
+                statistics.ExpenseCount++;
+            }
+            else if (record.Type == TransactionType.Income)
+            {
+                statistics.TotalIncome += amount;
+                statistics.IncomeCount++;
+            }
+        }
+
+        statistics.Balance = statistics.TotalIncome - statistics.TotalExpense;
+        statistics.TotalCount = records.Count;
+
+        return statistics;
+    }
+
     public async Task<List<CategoryStatistics>> GetCategoryStatisticsAsync(int year, int month, TransactionType type)
     {
         var records = await transactionRepository.QueryAsync(