add conversation pagination

src/Infrastructure/BotSharp.Abstraction/Repositories/IBotSharpRepository.cs

@@ -43,7 +43,7 @@ public interface IBotSharpRepository
     void UpdateConversationStates(string conversationId, List<StateKeyValue> states);
     void UpdateConversationStatus(string conversationId, string status);
     Conversation GetConversation(string conversationId);
-    List<Conversation> GetConversations(ConversationFilter filter);
+    PagedItems<Conversation> GetConversations(ConversationFilter filter);
     void UpdateConversationTitle(string conversationId, string title);
     List<Conversation> GetLastConversations();
     #endregion

src/Infrastructure/BotSharp.Abstraction/Utilities/Pagination.cs

@@ -2,12 +2,12 @@ namespace BotSharp.Abstraction.Utilities;
 
 public class Pagination
 {
-    public int Page { get; set; } = 0;
+    public int Page { get; set; } = 1;
     /// <summary>
     /// Use -1 for all records
     /// </summary>
     public int Size { get; set; } = 20;
-    public int Offset => (Page + 1) * Size;
+    public int Offset => (Page - 1) * Size;
 }
 
 public class PagedItems<T>

src/Infrastructure/BotSharp.Core/Conversations/Services/ConversationService.cs

@@ -57,14 +57,8 @@ public async Task<Conversation> GetConversation(string id)
     public async Task<PagedItems<Conversation>> GetConversations(ConversationFilter filter)
     {
         var db = _services.GetRequiredService<IBotSharpRepository>();
-        var user = db.GetUserById(_user.Id);
         var conversations = db.GetConversations(filter);
-        var result = new PagedItems<Conversation>
-        {
-            Count = conversations.Count(),
-            Items = conversations.OrderByDescending(x => x.CreatedTime)
-        };
-        return result;
+        return conversations;
     }
 
     public async Task<List<Conversation>> GetLastConversations()

src/Infrastructure/BotSharp.Core/Repository/BotSharpDbContext.cs

@@ -136,7 +136,7 @@ public Conversation GetConversation(string conversationId)
         throw new NotImplementedException();
     }
 
-    public List<Conversation> GetConversations(ConversationFilter filter)
+    public PagedItems<Conversation> GetConversations(ConversationFilter filter)
     {
         throw new NotImplementedException();
     }

src/Infrastructure/BotSharp.Core/Repository/FileRepository/FileRepository.Conversation.cs

@@ -200,12 +200,14 @@ public Conversation GetConversation(string conversationId)
             return record;
         }
 
-        public List<Conversation> GetConversations(ConversationFilter filter)
+        public PagedItems<Conversation> GetConversations(ConversationFilter filter)
         {
             var records = new List<Conversation>();
             var dir = Path.Combine(_dbSettings.FileRepository, _conversationSettings.DataDir);
+            var totalDirs = Directory.GetDirectories(dir);
+            var dirs = totalDirs.Skip(filter.Pager.Offset).Take(filter.Pager.Size).ToList();
 
-            foreach (var d in Directory.GetDirectories(dir))
+            foreach (var d in dirs)
             {
                 var path = Path.Combine(d, CONVERSATION_FILE);
                 if (!File.Exists(path)) continue;
@@ -225,7 +227,11 @@ public List<Conversation> GetConversations(ConversationFilter filter)
                 records.Add(record);
             }
 
-            return records;
+            return new PagedItems<Conversation>
+            {
+                Items = records.OrderByDescending(x => x.CreatedTime),
+                Count = totalDirs.Count(),
+            };
         }
 
         public List<Conversation> GetLastConversations()

src/Infrastructure/BotSharp.OpenAPI/Controllers/ConversationController.cs

@@ -30,8 +30,8 @@ public async Task<ConversationViewModel> NewConversation([FromRoute] string agen
         return ConversationViewModel.FromSession(conv);
     }
 
-    [HttpGet("/conversations")]
-    public async Task<PagedItems<ConversationViewModel>> GetConversations([FromQuery] ConversationFilter filter)
+    [HttpPost("/conversations")]
+    public async Task<PagedItems<ConversationViewModel>> GetConversations([FromBody] ConversationFilter filter)
     {
         var service = _services.GetRequiredService<IConversationService>();
         var conversations = await service.GetConversations(filter);

src/Plugins/BotSharp.Plugin.MongoStorage/Repository/MongoRepository.Conversation.cs

@@ -204,7 +204,7 @@ public Conversation GetConversation(string conversationId)
         };
     }
 
-    public List<Conversation> GetConversations(ConversationFilter filter)
+    public PagedItems<Conversation> GetConversations(ConversationFilter filter)
     {
         var conversations = new List<Conversation>();
         var builder = Builders<ConversationDocument>.Filter;
@@ -215,7 +215,10 @@ public List<Conversation> GetConversations(ConversationFilter filter)
         if (!string.IsNullOrEmpty(filter.Channel)) filters.Add(builder.Eq(x => x.Channel, filter.Channel));
         if (!string.IsNullOrEmpty(filter.UserId)) filters.Add(builder.Eq(x => x.UserId, filter.UserId));
 
-        var conversationDocs = _dc.Conversations.Find(builder.And(filters)).ToList();
+        var filterDef = builder.And(filters);
+        var sortDefinition = Builders<ConversationDocument>.Sort.Descending(x => x.CreatedTime);
+        var conversationDocs = _dc.Conversations.Find(filterDef).Sort(sortDefinition).Skip(filter.Pager.Offset).Limit(filter.Pager.Size).ToList();
+        var count = _dc.Conversations.CountDocuments(filterDef);
 
         foreach (var conv in conversationDocs)
         {
@@ -233,7 +236,11 @@ public List<Conversation> GetConversations(ConversationFilter filter)
             });
         }
 
-        return conversations;
+        return new PagedItems<Conversation>
+        {
+            Items = conversations,
+            Count = (int)count
+        };
     }
 
     public List<Conversation> GetLastConversations()