From 448ebd6036b3f2160e55c727f4fc4c8751beeebb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Burak=20Kaan=20K=C3=B6se?= <bkaankose@outlook.com>
Date: Sat, 11 Apr 2026 15:18:30 +0200
Subject: [PATCH] Respect API calendar colors unless overridden

---
 .../CalendarAccountSettingsPageViewModel.cs   |  1 +
 .../Entities/Calendar/AccountCalendar.cs      |  1 +
 Wino.Core/Synchronizers/GmailSynchronizer.cs  | 31 ++++++++++++++++---
 .../Synchronizers/OutlookSynchronizer.cs      | 29 ++++++++++++++---
 .../AccountDetailsPageViewModel.cs            |  1 +
 Wino.Services/DatabaseService.cs              |  9 ++++++
 6 files changed, 63 insertions(+), 9 deletions(-)

diff --git a/Wino.Calendar.ViewModels/CalendarAccountSettingsPageViewModel.cs b/Wino.Calendar.ViewModels/CalendarAccountSettingsPageViewModel.cs
index 79400c7d..69112b07 100644
--- a/Wino.Calendar.ViewModels/CalendarAccountSettingsPageViewModel.cs
+++ b/Wino.Calendar.ViewModels/CalendarAccountSettingsPageViewModel.cs
@@ -87,6 +87,7 @@ public partial class CalendarAccountSettingsPageViewModel : CalendarBaseViewMode
         if (AccountCalendar != null && !string.IsNullOrEmpty(value))
         {
             AccountCalendar.BackgroundColorHex = value;
+            AccountCalendar.IsBackgroundColorUserOverridden = true;
             SaveChangesAsync();
         }
     }
diff --git a/Wino.Core.Domain/Entities/Calendar/AccountCalendar.cs b/Wino.Core.Domain/Entities/Calendar/AccountCalendar.cs
index e3fe9ba6..79842c08 100644
--- a/Wino.Core.Domain/Entities/Calendar/AccountCalendar.cs
+++ b/Wino.Core.Domain/Entities/Calendar/AccountCalendar.cs
@@ -25,6 +25,7 @@ public class AccountCalendar : IAccountCalendar
     /// </summary>
     public string TextColorHex { get; set; }
     public string BackgroundColorHex { get; set; }
+    public bool IsBackgroundColorUserOverridden { get; set; }
     public string TimeZone { get; set; }
 
     [Ignore]
diff --git a/Wino.Core/Synchronizers/GmailSynchronizer.cs b/Wino.Core/Synchronizers/GmailSynchronizer.cs
index f2d2ec7f..9d6fc869 100644
--- a/Wino.Core/Synchronizers/GmailSynchronizer.cs
+++ b/Wino.Core/Synchronizers/GmailSynchronizer.cs
@@ -741,10 +741,11 @@ public class GmailSynchronizer : WinoSynchronizer<IClientServiceRequest, Message
             if (existingLocalCalendar == null)
             {
                 // Insert new calendar.
-                var fallbackColor = ColorHelpers.GetDistinctFlatColorHex(usedCalendarColors, calendar.BackgroundColor);
+                var remoteBackgroundColor = GetRemoteGmailCalendarBackgroundColor(calendar);
+                var fallbackColor = ColorHelpers.GetDistinctFlatColorHex(usedCalendarColors, remoteBackgroundColor);
                 var localCalendar = calendar.AsCalendar(Account.Id, fallbackColor);
                 localCalendar.IsPrimary = string.Equals(localCalendar.RemoteCalendarId, remotePrimaryCalendarId, StringComparison.OrdinalIgnoreCase);
-                localCalendar.BackgroundColorHex = ColorHelpers.GetDistinctFlatColorHex(usedCalendarColors, localCalendar.BackgroundColorHex);
+                localCalendar.BackgroundColorHex = ResolveSynchronizedCalendarBackgroundColor(remoteBackgroundColor, localCalendar, usedCalendarColors);
                 localCalendar.TextColorHex = ColorHelpers.GetReadableTextColorHex(localCalendar.BackgroundColorHex);
                 usedCalendarColors.Add(localCalendar.BackgroundColorHex);
                 insertedCalendars.Add(localCalendar);
@@ -752,7 +753,7 @@ public class GmailSynchronizer : WinoSynchronizer<IClientServiceRequest, Message
             else
             {
                 // Update existing calendar. Right now we only update the name.
-                var resolvedColor = ColorHelpers.GetDistinctFlatColorHex(usedCalendarColors, existingLocalCalendar.BackgroundColorHex);
+                var resolvedColor = ResolveSynchronizedCalendarBackgroundColor(GetRemoteGmailCalendarBackgroundColor(calendar), existingLocalCalendar, usedCalendarColors);
                 if (ShouldUpdateCalendar(calendar, existingLocalCalendar, remotePrimaryCalendarId) ||
                     !string.Equals(existingLocalCalendar.BackgroundColorHex, resolvedColor, StringComparison.OrdinalIgnoreCase))
                 {
@@ -939,8 +940,8 @@ public class GmailSynchronizer : WinoSynchronizer<IClientServiceRequest, Message
     {
         var remoteCalendarName = calendarListEntry.Summary;
         var remoteTimeZone = calendarListEntry.TimeZone;
-        var remoteBackgroundColor = string.IsNullOrEmpty(calendarListEntry.BackgroundColor) ? accountCalendar.BackgroundColorHex : calendarListEntry.BackgroundColor;
-        var remoteTextColor = string.IsNullOrEmpty(calendarListEntry.ForegroundColor) ? accountCalendar.TextColorHex : calendarListEntry.ForegroundColor;
+        var remoteBackgroundColor = ResolveSynchronizedCalendarBackgroundColor(GetRemoteGmailCalendarBackgroundColor(calendarListEntry), accountCalendar);
+        var remoteTextColor = ColorHelpers.GetReadableTextColorHex(remoteBackgroundColor);
         var remoteIsPrimary = string.Equals(calendarListEntry.Id, remotePrimaryCalendarId, StringComparison.OrdinalIgnoreCase);
 
         bool isNameChanged = !string.Equals(accountCalendar.Name, remoteCalendarName, StringComparison.OrdinalIgnoreCase);
@@ -952,6 +953,26 @@ public class GmailSynchronizer : WinoSynchronizer<IClientServiceRequest, Message
         return isNameChanged || isTimeZoneChanged || isBackgroundColorChanged || isTextColorChanged || isPrimaryChanged;
     }
 
+    private static string GetRemoteGmailCalendarBackgroundColor(CalendarListEntry calendarListEntry)
+        => string.IsNullOrWhiteSpace(calendarListEntry?.BackgroundColor) ? null : calendarListEntry.BackgroundColor;
+
+    private static string ResolveSynchronizedCalendarBackgroundColor(
+        string remoteBackgroundColor,
+        AccountCalendar accountCalendar,
+        ISet<string> usedCalendarColors = null)
+    {
+        if (accountCalendar.IsBackgroundColorUserOverridden)
+            return accountCalendar.BackgroundColorHex;
+
+        var preferredColor = string.IsNullOrWhiteSpace(remoteBackgroundColor)
+            ? accountCalendar.BackgroundColorHex
+            : remoteBackgroundColor;
+
+        return string.IsNullOrWhiteSpace(remoteBackgroundColor) && usedCalendarColors != null
+            ? ColorHelpers.GetDistinctFlatColorHex(usedCalendarColors, preferredColor)
+            : preferredColor;
+    }
+
     private string GetPrimaryCalendarId(IList<CalendarListEntry> remoteCalendars)
     {
         if (remoteCalendars == null || remoteCalendars.Count == 0)
diff --git a/Wino.Core/Synchronizers/OutlookSynchronizer.cs b/Wino.Core/Synchronizers/OutlookSynchronizer.cs
index 8790d6f9..fc6f19d2 100644
--- a/Wino.Core/Synchronizers/OutlookSynchronizer.cs
+++ b/Wino.Core/Synchronizers/OutlookSynchronizer.cs
@@ -2517,10 +2517,11 @@ public class OutlookSynchronizer : WinoSynchronizer<RequestInformation, Message,
             if (existingLocalCalendar == null)
             {
                 // Insert new calendar.
-                var fallbackColor = ColorHelpers.GetDistinctFlatColorHex(usedCalendarColors, calendar.HexColor);
+                var remoteBackgroundColor = GetRemoteOutlookCalendarBackgroundColor(calendar);
+                var fallbackColor = ColorHelpers.GetDistinctFlatColorHex(usedCalendarColors, remoteBackgroundColor);
                 var localCalendar = calendar.AsCalendar(Account, fallbackColor);
                 localCalendar.IsPrimary = string.Equals(localCalendar.RemoteCalendarId, remotePrimaryCalendarId, StringComparison.OrdinalIgnoreCase);
-                localCalendar.BackgroundColorHex = ColorHelpers.GetDistinctFlatColorHex(usedCalendarColors, localCalendar.BackgroundColorHex);
+                localCalendar.BackgroundColorHex = ResolveSynchronizedCalendarBackgroundColor(remoteBackgroundColor, localCalendar, usedCalendarColors);
                 localCalendar.TextColorHex = ColorHelpers.GetReadableTextColorHex(localCalendar.BackgroundColorHex);
                 usedCalendarColors.Add(localCalendar.BackgroundColorHex);
                 insertedCalendars.Add(localCalendar);
@@ -2528,7 +2529,7 @@ public class OutlookSynchronizer : WinoSynchronizer<RequestInformation, Message,
             else
             {
                 // Update existing calendar. Right now we only update the name.
-                var resolvedColor = ColorHelpers.GetDistinctFlatColorHex(usedCalendarColors, existingLocalCalendar.BackgroundColorHex);
+                var resolvedColor = ResolveSynchronizedCalendarBackgroundColor(GetRemoteOutlookCalendarBackgroundColor(calendar), existingLocalCalendar, usedCalendarColors);
                 if (ShouldUpdateCalendar(calendar, existingLocalCalendar, remotePrimaryCalendarId) ||
                     !string.Equals(existingLocalCalendar.BackgroundColorHex, resolvedColor, StringComparison.OrdinalIgnoreCase))
                 {
@@ -2570,7 +2571,7 @@ public class OutlookSynchronizer : WinoSynchronizer<RequestInformation, Message,
     private bool ShouldUpdateCalendar(Calendar calendar, AccountCalendar accountCalendar, string remotePrimaryCalendarId)
     {
         var remoteCalendarName = calendar.Name;
-        var remoteBackgroundColor = string.IsNullOrEmpty(calendar.HexColor) ? accountCalendar.BackgroundColorHex : calendar.HexColor;
+        var remoteBackgroundColor = ResolveSynchronizedCalendarBackgroundColor(GetRemoteOutlookCalendarBackgroundColor(calendar), accountCalendar);
         var remoteIsPrimary = string.Equals(calendar.Id, remotePrimaryCalendarId, StringComparison.OrdinalIgnoreCase);
 
         bool isNameChanged = !string.Equals(accountCalendar.Name, remoteCalendarName, StringComparison.OrdinalIgnoreCase);
@@ -2580,6 +2581,26 @@ public class OutlookSynchronizer : WinoSynchronizer<RequestInformation, Message,
         return isNameChanged || isBackgroundColorChanged || isPrimaryChanged;
     }
 
+    private static string GetRemoteOutlookCalendarBackgroundColor(Calendar calendar)
+        => string.IsNullOrWhiteSpace(calendar?.HexColor) ? null : calendar.HexColor;
+
+    private static string ResolveSynchronizedCalendarBackgroundColor(
+        string remoteBackgroundColor,
+        AccountCalendar accountCalendar,
+        ISet<string> usedCalendarColors = null)
+    {
+        if (accountCalendar.IsBackgroundColorUserOverridden)
+            return accountCalendar.BackgroundColorHex;
+
+        var preferredColor = string.IsNullOrWhiteSpace(remoteBackgroundColor)
+            ? accountCalendar.BackgroundColorHex
+            : remoteBackgroundColor;
+
+        return string.IsNullOrWhiteSpace(remoteBackgroundColor) && usedCalendarColors != null
+            ? ColorHelpers.GetDistinctFlatColorHex(usedCalendarColors, preferredColor)
+            : preferredColor;
+    }
+
     private async Task<string> GetPrimaryCalendarIdAsync(IList<Calendar> remoteCalendars, CancellationToken cancellationToken)
     {
         if (remoteCalendars == null || remoteCalendars.Count == 0)
diff --git a/Wino.Mail.ViewModels/AccountDetailsPageViewModel.cs b/Wino.Mail.ViewModels/AccountDetailsPageViewModel.cs
index b6d2d8f2..f2e11754 100644
--- a/Wino.Mail.ViewModels/AccountDetailsPageViewModel.cs
+++ b/Wino.Mail.ViewModels/AccountDetailsPageViewModel.cs
@@ -342,6 +342,7 @@ public partial class AccountDetailsPageViewModel : MailBaseViewModel
             return;
 
         calendarItem.SetBackgroundColor(color);
+        calendarItem.Calendar.IsBackgroundColorUserOverridden = true;
         await _calendarService.UpdateAccountCalendarAsync(calendarItem.Calendar);
     }
 
diff --git a/Wino.Services/DatabaseService.cs b/Wino.Services/DatabaseService.cs
index 18addf24..e617f3ae 100644
--- a/Wino.Services/DatabaseService.cs
+++ b/Wino.Services/DatabaseService.cs
@@ -142,6 +142,15 @@ public class DatabaseService : IDatabaseService
                 .ConfigureAwait(false);
         }
 
+        var accountCalendarColumns = await Connection.GetTableInfoAsync(nameof(AccountCalendar)).ConfigureAwait(false);
+
+        if (!accountCalendarColumns.Any(c => c.Name == nameof(AccountCalendar.IsBackgroundColorUserOverridden)))
+        {
+            await Connection
+                .ExecuteAsync($"ALTER TABLE {nameof(AccountCalendar)} ADD COLUMN {nameof(AccountCalendar.IsBackgroundColorUserOverridden)} INTEGER NOT NULL DEFAULT 0")
+                .ConfigureAwait(false);
+        }
+
         await Connection.ExecuteAsync("DROP TABLE IF EXISTS WinoAccountAddOnCache").ConfigureAwait(false);
     }