Восстановление подключения, бэк

backend/src/Contracts/Messaging/Application/Abstractions/IMessageRepository.cs

@@ -13,6 +13,7 @@ public interface IMessageRepository
 
     Task<List<Message>> GetChatMessagesCursorAsync(Guid chatId, DateTime? cursor, long? sequenceId, int limit, CancellationToken cancellationToken);
     Task<List<Message>> GetChatMessagesAroundAsync(Guid chatId, long sequenceId, int limit, CancellationToken cancellationToken);
+    Task<List<Message>> GetChatMessagesAfterAsync(Guid chatId, long sequenceId, int limit, CancellationToken cancellationToken);
     Task<Message?> GetLastStoryMessageAsync(Guid chatId, Guid storyId, CancellationToken cancellationToken);
 
     Task UpdateAsync(Message message, CancellationToken cancellationToken);

backend/src/Modules/Conversations/Application/Messages/GetMessages/GetMessagesQuery.cs

@@ -13,7 +13,7 @@ using MediatR;
 
 namespace Knot.Modules.Conversations.Application.Messages.GetMessages;
 
-public record GetMessagesQuery(Guid UserId, Guid ChatId, string? Cursor, long? Pivot = null, int? Limit = null) : IQuery<List<MessageDetailDto>>;
+public record GetMessagesQuery(Guid UserId, Guid ChatId, string? Cursor, long? Pivot = null, long? AfterSequenceId = null, int? Limit = null) : IQuery<List<MessageDetailDto>>;
 
 internal sealed class GetMessagesQueryHandler : IQueryHandler<GetMessagesQuery, List<MessageDetailDto>>
 {
@@ -41,7 +41,12 @@ internal sealed class GetMessagesQueryHandler : IQueryHandler<GetMessagesQuery,
         List<Message> messages;
         int queryLimit = request.Limit ?? ChatConstants.DefaultMessageQueryLimit;
 
-        if (request.Pivot.HasValue)
+        if (request.AfterSequenceId.HasValue)
+        {
+            // Получаем только сообщения ПОСЛЕ указанного sequenceId (для синхронизации)
+            messages = await _messageRepository.GetChatMessagesAfterAsync(request.ChatId, request.AfterSequenceId.Value, queryLimit, cancellationToken);
+        }
+        else if (request.Pivot.HasValue)
         {
             messages = await _messageRepository.GetChatMessagesAroundAsync(request.ChatId, request.Pivot.Value, queryLimit, cancellationToken);
         }

backend/src/Modules/Conversations/Presentation/Endpoints/MessagesEndpoints.cs

@@ -19,9 +19,17 @@ public static class MessagesEndpoints
     {
         var group = app.MapGroup("api/messages").RequireAuthorization();
 
-        group.MapGet("chat/{chatId:guid}", async ([FromRoute] Guid chatId, [FromQuery] string? cursor, ISender sender, IUserContext userContext, CancellationToken ct) =>
+        group.MapGet("chat/{chatId:guid}", async (
+            [FromRoute] Guid chatId,
+            [FromQuery] string? cursor,
+            [FromQuery] long? afterSequenceId,
+            [FromQuery] long? pivot,
+            [FromQuery] int? limit,
+            ISender sender,
+            IUserContext userContext,
+            CancellationToken ct) =>
         {
-            var result = await sender.Send(new GetMessagesQuery(userContext.UserId, chatId, cursor), ct);
+            var result = await sender.Send(new GetMessagesQuery(userContext.UserId, chatId, cursor, pivot, afterSequenceId, limit), ct);
             return result.IsSuccess ? Results.Ok(result.Value) : Results.BadRequest(result.Error.Description);
         });
 

backend/src/Modules/Messaging/Infrastructure/Persistence/MessageRepository.cs

@@ -95,14 +95,28 @@ public sealed class MessageRepository : IMessageRepository
             .ToListAsync(cancellationToken);
     }
 
+    public async Task<List<Message>> GetChatMessagesAfterAsync(Guid chatId, long sequenceId, int limit, CancellationToken cancellationToken)
+    {
+        var builder = Builders<Message>.Filter;
+        var filter = builder.And(
+            builder.Eq(m => m.ChatId, chatId),
+            builder.Gt(m => m.SequenceId, sequenceId)
+        );
+
+        return await _messages.Find(filter)
+            .SortBy(m => m.SequenceId)
+            .Limit(limit)
+            .ToListAsync(cancellationToken);
+    }
+
     public async Task<List<Message>> GetChatMessagesAroundAsync(Guid chatId, long sequenceId, int limit, CancellationToken cancellationToken)
     {
         var builder = Builders<Message>.Filter;
-        
+
         // Target message
         var targetFilter = builder.And(builder.Eq(m => m.ChatId, chatId), builder.Eq(m => m.SequenceId, sequenceId));
         var targetMsg = await _messages.Find(targetFilter).FirstOrDefaultAsync(cancellationToken);
-        
+
         // Older messages
         var olderFilter = builder.And(builder.Eq(m => m.ChatId, chatId), builder.Lt(m => m.SequenceId, sequenceId));
         var older = await _messages.Find(olderFilter)