todo

Service/Budget/BudgetSavingsService.cs

@@ -0,0 +1,80 @@
+namespace Service.Budget;
+
+public interface IBudgetSavingsService
+{
+    Task<BudgetResult> GetSavingsDtoAsync(
+        BudgetPeriodType periodType,
+        DateTime? referenceDate = null,
+        IEnumerable<BudgetRecord>? existingBudgets = null);
+}
+
+public class BudgetSavingsService(
+    IBudgetRepository budgetRepository,
+    IBudgetArchiveRepository budgetArchiveRepository
+) : IBudgetSavingsService
+{
+    public async Task<BudgetResult> GetSavingsDtoAsync(
+        BudgetPeriodType periodType,
+        DateTime? referenceDate = null,
+        IEnumerable<BudgetRecord>? existingBudgets = null)
+    {
+        var budgets = existingBudgets;
+
+        if (existingBudgets == null)
+        {
+            budgets = await budgetRepository.GetAllAsync();
+        }
+
+        if (budgets == null)
+        {
+            throw new InvalidOperationException("No budgets found.");
+        }
+
+        budgets = budgets
+        // 排序顺序 1.硬性预算 2.月度->年度 3.实际金额倒叙
+            .OrderBy(b => b.IsMandatoryExpense)
+            .ThenBy(b => b.Type)
+            .ThenByDescending(b => b.Limit);
+
+        var year = referenceDate?.Year ?? DateTime.Now.Year;
+        var month = referenceDate?.Month ?? DateTime.Now.Month;
+        
+        if(periodType == BudgetPeriodType.Month)
+        {
+            return await GetForMonthAsync(budgets, year, month);  
+        }
+        else if(periodType == BudgetPeriodType.Year)
+        {
+            return await GetForYearAsync(budgets, year);
+        }
+
+        throw new NotSupportedException($"Period type {periodType} is not supported.");
+    }
+
+    private async Task<BudgetResult> GetForMonthAsync(
+        IEnumerable<BudgetRecord> budgets,
+        int year, 
+        int month)
+    {
+        var result = new BudgetResult
+        {
+            
+        };
+
+        var monthlyBudgets = budgets
+            .Where(b => b.Type == BudgetPeriodType.Month);
+        var yearlyBudgets = budgets
+            .Where(b => b.Type == BudgetPeriodType.Year);
+
+        // var actualAmount = await budgetRepository.GetCurrentAmountAsync(budget, startDate, endDate);
+
+        throw new NotImplementedException();
+    }
+
+    private async Task<BudgetResult> GetForYearAsync(
+        IEnumerable<BudgetRecord> budgets,
+        int year)
+    {
+        throw new NotImplementedException();
+    }
+}