R47 A1-A8：完成薪资管理模块

server/src/services/employeeStats.js

@@ -6,6 +6,10 @@ function addDays(date, days) {
   return next;
 }
 
+function shiftMonth(date, months) {
+  return new Date(Date.UTC(date.getUTCFullYear(), date.getUTCMonth() + months, 1));
+}
+
 function toNumber(value) {
   return value == null ? null : Number(value);
 }
@@ -24,13 +28,29 @@ function buildPerformanceDistribution(rows) {
 
 async function buildEmployeeStats(prisma, options = {}) {
   const timeZone = options.timeZone ?? "Asia/Shanghai";
+  const includeSalarySummary = options.includeSalarySummary ?? true;
   const todayString = currentDateString(timeZone);
   const today = parseDateOnlyString(todayString);
   const last30DateFrom = addDays(today, -29);
   const next30DateTo = addDays(today, 30);
+  const currentMonthStart = parseDateOnlyString(`${todayString.slice(0, 7)}-01`);
+  const previousMonthStart = shiftMonth(currentMonthStart, -1);
   const activeEmployeeWhere = { status: "active" };
 
-  const [employmentStatusRows, departmentRows, departments, recentHires, recentDepartures, expiringContracts, validCertificateHolders, expiringCertificates, activeCycle, completedCycle] = await Promise.all([
+  const [
+    employmentStatusRows,
+    departmentRows,
+    departments,
+    recentHires,
+    recentDepartures,
+    expiringContracts,
+    validCertificateHolders,
+    expiringCertificates,
+    activeCycle,
+    completedCycle,
+    currentMonthSalaryAggregate,
+    previousMonthSalaryAggregate,
+  ] = await Promise.all([
     prisma.employee.groupBy({
       by: ["employment_status"],
       where: activeEmployeeWhere,
@@ -102,6 +122,28 @@ async function buildEmployeeStats(prisma, options = {}) {
       where: { status: "completed" },
       orderBy: [{ completed_at: "desc" }, { end_date: "desc" }],
     }),
+    includeSalarySummary
+      ? prisma.payslip.aggregate({
+          where: {
+            pay_month: currentMonthStart,
+            status: "issued",
+          },
+          _sum: { net_amount: true },
+          _avg: { net_amount: true },
+          _count: { _all: true },
+        })
+      : Promise.resolve(null),
+    includeSalarySummary
+      ? prisma.payslip.aggregate({
+          where: {
+            pay_month: previousMonthStart,
+            status: "issued",
+          },
+          _sum: { net_amount: true },
+          _avg: { net_amount: true },
+          _count: { _all: true },
+        })
+      : Promise.resolve(null),
   ]);
 
   const departmentMap = new Map(departments.map((item) => [item.id, item.name]));
@@ -142,6 +184,29 @@ async function buildEmployeeStats(prisma, options = {}) {
     };
   }
 
+  const salarySummary = includeSalarySummary
+    ? {
+        currentMonth:
+          currentMonthSalaryAggregate?._count?._all > 0
+            ? {
+                month: currentMonthStart.toISOString().slice(0, 7),
+                totalNetAmount: toNumber(currentMonthSalaryAggregate._sum.net_amount) ?? 0,
+                averageNetAmount: toNumber(currentMonthSalaryAggregate._avg.net_amount) ?? 0,
+                issuedCount: currentMonthSalaryAggregate._count._all,
+              }
+            : null,
+        previousMonth:
+          previousMonthSalaryAggregate?._count?._all > 0
+            ? {
+                month: previousMonthStart.toISOString().slice(0, 7),
+                totalNetAmount: toNumber(previousMonthSalaryAggregate._sum.net_amount) ?? 0,
+                averageNetAmount: toNumber(previousMonthSalaryAggregate._avg.net_amount) ?? 0,
+                issuedCount: previousMonthSalaryAggregate._count._all,
+              }
+            : null,
+      }
+    : null;
+
   return {
     asOfDate: todayString,
     employmentStatusSummary: {
@@ -177,6 +242,7 @@ async function buildEmployeeStats(prisma, options = {}) {
       validHolderCount: validCertificateHolders.length,
       expiringSoonCount: expiringCertificates,
     },
+    salarySummary,
     performanceSummary,
   };
 }