From 5667c2e12fd13cbdd28f573ed3c2640fca04f507 Mon Sep 17 00:00:00 2001
From: Duncan Tourolle <duncan@tourolle.paris>
Date: Sat, 27 Jun 2026 09:34:07 +0200
Subject: [PATCH] Cache manageent for bussines units

---
 .../Services/CategoryService.cs               | 30 ++++++++++---------
 1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/Jellyfin.Plugin.SRFPlay/Services/CategoryService.cs b/Jellyfin.Plugin.SRFPlay/Services/CategoryService.cs
index 81c8c2a..94b2f83 100644
--- a/Jellyfin.Plugin.SRFPlay/Services/CategoryService.cs
+++ b/Jellyfin.Plugin.SRFPlay/Services/CategoryService.cs
@@ -18,8 +18,10 @@ public class CategoryService : ICategoryService
     private readonly ILogger<CategoryService> _logger;
     private readonly ISRFApiClientFactory _apiClientFactory;
     private readonly TimeSpan _topicsCacheDuration = TimeSpan.FromHours(24);
-    private Dictionary<string, PlayV3Topic>? _topicsCache;
-    private DateTime _topicsCacheExpiry = DateTime.MinValue;
+
+    // Cache topics per business unit. A single shared cache would return one unit's
+    // topics (e.g. German SRF) even after the user switched to another (e.g. French RTS).
+    private readonly Dictionary<string, (Dictionary<string, PlayV3Topic> Topics, DateTime Expiry)> _topicsCacheByUnit = new(StringComparer.OrdinalIgnoreCase);
 
     /// <summary>
     /// Initializes a new instance of the <see cref="CategoryService"/> class.
@@ -35,11 +37,11 @@ public class CategoryService : ICategoryService
     /// <inheritdoc />
     public async Task<List<PlayV3Topic>> GetTopicsAsync(string businessUnit, CancellationToken cancellationToken = default)
     {
-        // Return cached topics if still valid
-        if (_topicsCache != null && DateTime.UtcNow < _topicsCacheExpiry)
+        // Return cached topics for this business unit if still valid
+        if (_topicsCacheByUnit.TryGetValue(businessUnit, out var cached) && DateTime.UtcNow < cached.Expiry)
         {
             _logger.LogDebug("Returning cached topics for business unit: {BusinessUnit}", businessUnit);
-            return _topicsCache.Values.ToList();
+            return cached.Topics.Values.ToList();
         }
 
         _logger.LogInformation("Fetching topics for business unit: {BusinessUnit}", businessUnit);
@@ -48,13 +50,13 @@ public class CategoryService : ICategoryService
 
         if (topics != null && topics.Count > 0)
         {
-            // Cache topics by ID for quick lookups
-            _topicsCache = topics
+            // Cache topics by ID for quick lookups, scoped to this business unit
+            var byId = topics
                 .Where(t => !string.IsNullOrEmpty(t.Id))
                 .ToDictionary(t => t.Id!, t => t);
-            _topicsCacheExpiry = DateTime.UtcNow.Add(_topicsCacheDuration);
+            _topicsCacheByUnit[businessUnit] = (byId, DateTime.UtcNow.Add(_topicsCacheDuration));
 
-            _logger.LogInformation("Cached {Count} topics for business unit: {BusinessUnit}", _topicsCache.Count, businessUnit);
+            _logger.LogInformation("Cached {Count} topics for business unit: {BusinessUnit}", byId.Count, businessUnit);
         }
 
         return topics ?? new List<PlayV3Topic>();
@@ -63,13 +65,14 @@ public class CategoryService : ICategoryService
     /// <inheritdoc />
     public async Task<PlayV3Topic?> GetTopicByIdAsync(string topicId, string businessUnit, CancellationToken cancellationToken = default)
     {
-        // Ensure topics are loaded
-        if (_topicsCache == null || DateTime.UtcNow >= _topicsCacheExpiry)
+        // Ensure topics are loaded for this business unit
+        if (!_topicsCacheByUnit.TryGetValue(businessUnit, out var cached) || DateTime.UtcNow >= cached.Expiry)
         {
             await GetTopicsAsync(businessUnit, cancellationToken).ConfigureAwait(false);
+            _topicsCacheByUnit.TryGetValue(businessUnit, out cached);
         }
 
-        return _topicsCache?.GetValueOrDefault(topicId);
+        return cached.Topics?.GetValueOrDefault(topicId);
     }
 
     /// <inheritdoc />
@@ -101,8 +104,7 @@ public class CategoryService : ICategoryService
     /// <inheritdoc />
     public void ClearCache()
     {
-        _topicsCache = null;
-        _topicsCacheExpiry = DateTime.MinValue;
+        _topicsCacheByUnit.Clear();
         _logger.LogInformation("Topics cache cleared");
     }