fix(analytics): add validation for date range filters in OPT status API

Author: alishawalunj

src/controllers/optAnalyticsController.js

@@ -5,25 +5,68 @@ module.exports = () => ({
     try {
       const { startDate, endDate, role } = req.query;
       const query = {};
-      if (startDate || endDate) {
+
+      let start;
+      let end;
+
+      if (startDate) {
+        start = new Date(startDate);
+        if (Number.isNaN(start.getTime())) {
+          return res.status(400).json({
+            message: 'Invalid startDate. Use ISO format (YYYY-MM-DD).',
+          });
+        }
+      }
+
+      if (endDate) {
+        end = new Date(endDate);
+        if (Number.isNaN(end.getTime())) {
+          return res.status(400).json({
+            message: 'Invalid endDate. Use ISO format (YYYY-MM-DD).',
+          });
+        }
+      }
+
+      if (start && end && start > end) {
+        return res.status(400).json({
+          message: 'startDate cannot be greater than endDate.',
+        });
+      }
+
+      if (start || end) {
         query.applicationDate = {};
-        if (startDate) query.applicationDate.$gte = new Date(startDate);
-        if (endDate) query.applicationDate.$lte = new Date(endDate);
+        if (start) query.applicationDate.$gte = start;
+        if (end) query.applicationDate.$lte = end;
       }
-      if (role) query.role = role;
+
+      if (role) {
+        query.role = role;
+      }
+
       const result = await CandidateOPTStatus.find(query);
+
+      if (!result.length) {
+        return res.json({
+          totalCandidates: 0,
+          breakDown: [],
+          message: 'No records found for the given filters.',
+        });
+      }
+
       const totalCandidates = result.length;
       const breakDownMap = {};
-      result.forEach((candidate) => {
-        const { optStatus } = candidate;
+
+      result.forEach(({ optStatus }) => {
         breakDownMap[optStatus] = (breakDownMap[optStatus] || 0) + 1;
       });
+
       const breakDown = Object.entries(breakDownMap).map(([optStatus, count]) => ({
         optStatus,
         count,
-        percentage: parseFloat(((count / totalCandidates) * 100).toFixed(2)),
+        percentage: Number(((count / totalCandidates) * 100).toFixed(2)),
       }));
-      res.json({
+
+      return res.json({
         totalCandidates,
         breakDown,
       });