add state change event

src/Infrastructure/BotSharp.Abstraction/Conversations/ConversationHookBase.cs

@@ -29,7 +29,7 @@ public abstract class ConversationHookBase : IConversationHook
     public virtual Task OnStateLoaded(ConversationState state)
         => Task.CompletedTask;
 
-    public virtual Task OnStateChanged(string name, string preValue, string currentValue)
+    public virtual Task OnStateChanged(StateChangeModel stateChange)
         => Task.CompletedTask;
 
     public virtual Task OnDialogRecordLoaded(RoleDialogModel dialog)

src/Infrastructure/BotSharp.Abstraction/Conversations/IConversationHook.cs

@@ -43,7 +43,7 @@ public interface IConversationHook
     Task OnDialogRecordLoaded(RoleDialogModel dialog);
 
     Task OnStateLoaded(ConversationState state);
-    Task OnStateChanged(string name, string preValue, string currentValue);
+    Task OnStateChanged(StateChangeModel stateChange);
 
     Task OnMessageReceived(RoleDialogModel message);
     Task OnPostbackMessageReceived(RoleDialogModel message, PostbackMessageModel replyMsg);

src/Infrastructure/BotSharp.Abstraction/Conversations/Models/StateChangeModel.cs

@@ -0,0 +1,19 @@
+namespace BotSharp.Abstraction.Conversations.Models;
+
+public class StateChangeModel
+{
+    [JsonPropertyName("conversation_id")]
+    public string ConversationId { get; set; }
+
+    [JsonPropertyName("message_id")]
+    public string MessageId { get; set; }
+
+    [JsonPropertyName("name")]
+    public string Name { get; set; }
+
+    [JsonPropertyName("before_value")]
+    public string BeforeValue { get; set; }
+
+    [JsonPropertyName("after_value")]
+    public string AfterValue { get; set; }
+}

src/Infrastructure/BotSharp.Abstraction/Loggers/Models/StateChangeOutputModel.cs

@@ -0,0 +1,7 @@
+namespace BotSharp.Abstraction.Loggers.Models;
+
+public class StateChangeOutputModel : StateChangeModel
+{
+    [JsonPropertyName("created_at")]
+    public DateTime CreateTime { get; set; } = DateTime.UtcNow;
+}

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

@@ -52,12 +52,20 @@ public class ConversationStateService : IConversationStateService, IDisposable
         if (!ContainsState(name) || preValue != currentValue)
         {
             _logger.LogInformation($"[STATE] {name} = {value}");
+            var routingCtx = _services.GetRequiredService<IRoutingContext>();
+
             foreach (var hook in hooks)
             {
-                hook.OnStateChanged(name, preValue, currentValue).Wait();
+                hook.OnStateChanged(new StateChangeModel
+                {
+                    ConversationId = _conversationId,
+                    MessageId = routingCtx.MessageId,
+                    Name = name,
+                    BeforeValue = preValue,
+                    AfterValue = currentValue
+                }).Wait();
             }
             
-            var routingCtx = _services.GetRequiredService<IRoutingContext>();
             var newPair = new StateKeyValue
             {
                 Key = name,

src/Plugins/BotSharp.Plugin.ChatHub/Hooks/StreamingLogHook.cs

@@ -213,6 +213,12 @@ public class StreamingLogHook : ConversationHookBase, IContentGeneratingHook, IR
         await _chatHub.Clients.User(_user.Id).SendAsync("OnConversationContentLogGenerated", BuildContentLog(input));
     }
 
+    public override async Task OnStateChanged(StateChangeModel stateChange)
+    {
+        if (stateChange == null) return;
+
+        await _chatHub.Clients.User(_user.Id).SendAsync("OnStateChangeGenerated", BuildStateChangeLog(stateChange));
+    }
     #endregion
 
     #region IRoutingHook
@@ -379,4 +385,19 @@ public class StreamingLogHook : ConversationHookBase, IContentGeneratingHook, IR
 
         return JsonSerializer.Serialize(log, _options.JsonSerializerOptions);
     }
+
+    private string BuildStateChangeLog(StateChangeModel stateChange)
+    {
+        var log = new StateChangeOutputModel
+        {
+            ConversationId = stateChange.ConversationId,
+            MessageId = stateChange.MessageId,
+            Name = stateChange.Name,
+            BeforeValue = stateChange.BeforeValue,
+            AfterValue = stateChange.AfterValue,
+            CreateTime = DateTime.UtcNow
+        };
+
+        return JsonSerializer.Serialize(log, _options.JsonSerializerOptions);
+    }
 }