From 2e12d73151dd6d8f3af53b96934a5833cd6bbafa Mon Sep 17 00:00:00 2001
From: Faris Armoush <farmoush@uba.com.jo>
Date: Sun, 1 Jun 2025 13:11:29 +0300
Subject: [PATCH] randomize generated fake data in
 `FakeAirQualityDistributionService`.

---
 ...fake_air_quality_distribution_service.dart | 55 +++++++++++++++----
 1 file changed, 43 insertions(+), 12 deletions(-)

diff --git a/lib/pages/analytics/services/air_quality_distribution/fake_air_quality_distribution_service.dart b/lib/pages/analytics/services/air_quality_distribution/fake_air_quality_distribution_service.dart
index 59f4947b..264addab 100644
--- a/lib/pages/analytics/services/air_quality_distribution/fake_air_quality_distribution_service.dart
+++ b/lib/pages/analytics/services/air_quality_distribution/fake_air_quality_distribution_service.dart
@@ -11,23 +11,54 @@ class FakeAirQualityDistributionService implements AirQualityDistributionService
   Future<List<AirQualityDataModel>> getAirQualityDistribution(
     GetAirQualityDistributionParam param,
   ) async {
-    return List.generate(30, (index) {
-      final date = DateTime(2025, 5, 1).add(Duration(days: index));
+    return Future.delayed(
+      const Duration(milliseconds: 400),
+      () => List.generate(30, (index) {
+        final date = DateTime(2025, 5, 1).add(Duration(days: index));
 
-      final values = _generateRandomPercentages();
+        final values = _generateRandomPercentages();
+        final nullMask = List.generate(6, (_) => _shouldBeNull());
 
-      return AirQualityDataModel(
-        date: date,
-        good: values[0],
-        moderate: values[1],
-        poor: values[2],
-        unhealthy: values[3],
-        severe: values[4],
-        hazardous: values[5],
-      );
+        // If all values are null, force at least one to be non-null
+        if (nullMask.every((isNull) => isNull)) {
+          nullMask[_random.nextInt(6)] = false;
+        }
+
+        // Redistribute percentages among non-null values
+        final nonNullValues = _redistributePercentages(values, nullMask);
+
+        return AirQualityDataModel(
+          date: date,
+          good: nullMask[0] ? null : nonNullValues[0],
+          moderate: nullMask[1] ? null : nonNullValues[1],
+          poor: nullMask[2] ? null : nonNullValues[2],
+          unhealthy: nullMask[3] ? null : nonNullValues[3],
+          severe: nullMask[4] ? null : nonNullValues[4],
+          hazardous: nullMask[5] ? null : nonNullValues[5],
+        );
+      }),
+    );
+  }
+
+  List<double> _redistributePercentages(
+      List<double> originalValues, List<bool> nullMask) {
+    // Calculate total of non-null values
+    double nonNullSum = 0;
+    for (int i = 0; i < originalValues.length; i++) {
+      if (!nullMask[i]) {
+        nonNullSum += originalValues[i];
+      }
+    }
+
+    // Redistribute percentages to maintain 100% total
+    return List.generate(originalValues.length, (i) {
+      if (nullMask[i]) return 0;
+      return (originalValues[i] / nonNullSum * 100).roundToDouble();
     });
   }
 
+  bool _shouldBeNull() => _random.nextDouble() < 0.6;
+
   List<double> _generateRandomPercentages() {
     final values = List.generate(6, (_) => _random.nextDouble());