From e52bcac75bca052e9e9bd08d1180a1d718a87a3c Mon Sep 17 00:00:00 2001
From: Johannes Vedder <johannes.vedder@student.hpi.de>
Date: Tue, 15 Aug 2023 17:01:52 +0200
Subject: [PATCH] fix(#432): fallback to id sorting if predicates provide equal
 result

---
 core/lib/src/models/tables/study.dart          |  7 ++++++-
 .../lib/common_views/standard_table.dart       | 18 +++++++++++++++---
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/core/lib/src/models/tables/study.dart b/core/lib/src/models/tables/study.dart
index 1b516330e..a3e5aa34f 100644
--- a/core/lib/src/models/tables/study.dart
+++ b/core/lib/src/models/tables/study.dart
@@ -35,7 +35,7 @@ enum ResultSharing {
 }
 
 @JsonSerializable()
-class Study extends SupabaseObjectFunctions<Study> {
+class Study extends SupabaseObjectFunctions<Study> implements Comparable<Study> {
   static const String tableName = 'study';
 
   @override
@@ -246,4 +246,9 @@ class Study extends SupabaseObjectFunctions<Study> {
   String toString() {
     return 'Study{id: $id, title: $title, description: $description, userId: $userId, participation: $participation, resultSharing: $resultSharing, contact: $contact, iconName: $iconName, published: $published, questionnaire: $questionnaire, eligibilityCriteria: $eligibilityCriteria, consent: $consent, interventions: $interventions, observations: $observations, schedule: $schedule, reportSpecification: $reportSpecification, results: $results, collaboratorEmails: $collaboratorEmails, registryPublished: $registryPublished, participantCount: $participantCount, endedCount: $endedCount, activeSubjectCount: $activeSubjectCount, missedDays: $missedDays, repo: $repo, invites: $invites, participants: $participants, participantsProgress: $participantsProgress, createdAt: $createdAt}';
   }
+
+  @override
+  int compareTo(Study other) {
+    return id.compareTo(other.id);
+  }
 }
diff --git a/designer_v2/lib/common_views/standard_table.dart b/designer_v2/lib/common_views/standard_table.dart
index 7205e0f85..967c77508 100644
--- a/designer_v2/lib/common_views/standard_table.dart
+++ b/designer_v2/lib/common_views/standard_table.dart
@@ -245,10 +245,22 @@ class _StandardTableState<T> extends State<StandardTable<T>> {
     }
   }
 
-  int _sortLogic(T a, T b, {required int columnIndex, required bool? sortAscending}) {
+  int _sortLogic(T a, T b, {required int columnIndex, required bool? sortAscending, bool? useSortPredicate}) {
     final sortPredicate = widget.sortColumnPredicates;
-    if (sortPredicate != null && sortPredicate[columnIndex] != null) {
-      return sortAscending ?? true ? sortPredicate[columnIndex]!(a, b) : sortPredicate[columnIndex]!(b, a);
+    if (useSortPredicate != null && useSortPredicate &&
+        sortPredicate != null && sortPredicate[columnIndex] != null
+    ) {
+      final int res;
+      if (sortAscending ?? true) {
+        res = sortPredicate[columnIndex]!(a, b);
+      } else {
+        res = sortPredicate[columnIndex]!(b, a);
+      }
+      if (res == 0) {
+        // Fallback to default sorting algorithm
+        return _sortLogic(a, b, columnIndex: columnIndex, sortAscending: sortAscending, useSortPredicate: false);
+      }
+      return res;
     } else if (a is Comparable && b is Comparable) {
       // If sortPredicate is not provided, use default comparison logic
       return sortAscending ?? true ? Comparable.compare(a, b) : Comparable.compare(b, a);