Add maxRecursiveDepth to avoid keeping calling LLM.

src/Infrastructure/BotSharp.Core/Agents/Services/AgentHookBase.cs

@@ -1,5 +1,4 @@
 using BotSharp.Abstraction.Agents.Models;
-using BotSharp.Abstraction.Conversations.Models;
 using Fluid;
 
 namespace BotSharp.Core.Agents.Services;
@@ -67,9 +66,4 @@ public virtual bool OnSamplesLoaded(ref string samples)
     public virtual void  OnAgentLoaded(Agent agent)
     {
     }
-
-    public virtual bool OnAgentRouting(RoleDialogModel message, ref string id)
-    {
-        return true;
-    }
 }

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

@@ -0,0 +1,42 @@
+using BotSharp.Abstraction.Conversations.Models;
+using BotSharp.Abstraction.Functions;
+
+namespace BotSharp.Core.Conversations.Services;
+
+public partial class ConversationService
+{
+    private async Task CallFunctions(RoleDialogModel msg)
+    {
+        var hooks = _services.GetServices<IConversationHook>().ToList();
+
+        // Invoke functions
+        var functions = _services.GetServices<IFunctionCallback>()
+            .Where(x => x.Name == msg.FunctionName)
+            .ToList();
+
+        if (functions.Count == 0)
+        {
+            msg.Content = $"Can't find function implementation of {msg.FunctionName}.";
+            _logger.LogError(msg.Content);
+            return;
+        }
+
+        foreach (var fn in functions)
+        {
+            // Before executing functions
+            foreach (var hook in hooks)
+            {
+                await hook.OnFunctionExecuting(msg);
+            }
+
+            // Execute function
+            await fn.Execute(msg);
+
+            // After functions have been executed
+            foreach (var hook in hooks)
+            {
+                await hook.OnFunctionExecuted(msg);
+            }
+        }
+    }
+}

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

@@ -0,0 +1,101 @@
+using BotSharp.Abstraction.Agents.Enums;
+using BotSharp.Abstraction.Agents.Models;
+using BotSharp.Abstraction.Conversations.Models;
+using BotSharp.Abstraction.MLTasks;
+
+namespace BotSharp.Core.Conversations.Services;
+
+public partial class ConversationService
+{
+    const int maxRecursiveDepth = 3;
+    int currentRecursiveDepth = 0;
+
+    private async Task<bool> GetChatCompletionsAsyncRecursively(IChatCompletion chatCompletion,
+        string conversationId,
+        Agent agent, 
+        List<RoleDialogModel> wholeDialogs,
+        Func<RoleDialogModel, Task> onMessageReceived,
+        Func<RoleDialogModel, Task> onFunctionExecuting)
+    {
+        currentRecursiveDepth++;
+        if (currentRecursiveDepth > maxRecursiveDepth)
+        {
+            _logger.LogError($"Exceed max current recursive depth.");
+            await HandleAssistantMessage(new RoleDialogModel(AgentRole.Assistant, "System has exception, please try later.")
+            {
+                CurrentAgentId = agent.Id
+            }, onMessageReceived);
+            return false;
+        }
+
+        var result = await chatCompletion.GetChatCompletionsAsync(agent, wholeDialogs, async msg =>
+        {
+            await HandleAssistantMessage(msg, onMessageReceived);
+
+            // Add to dialog history
+            _storage.Append(conversationId, agent.Id, msg);
+        }, async fn =>
+        {
+            var preAgentId = agent.Id;
+
+            await HandleFunctionMessage(fn, onFunctionExecuting);
+
+            // Function executed has exception
+            if (fn.ExecutionResult == null)
+            {
+                await HandleAssistantMessage(new RoleDialogModel(AgentRole.Assistant, fn.Content)
+                {
+                    CurrentAgentId = fn.CurrentAgentId
+                }, onMessageReceived);
+                return;
+            }
+
+            fn.Content = fn.ExecutionResult;
+
+            // Agent has been transferred
+            if (fn.CurrentAgentId != preAgentId)
+            {
+                var agentSettings = _services.GetRequiredService<AgentSettings>();
+                var agentService = _services.GetRequiredService<IAgentService>();
+                agent = await agentService.LoadAgent(fn.CurrentAgentId);
+
+                // Set state to make next conversation will go to this agent directly
+                // var state = _services.GetRequiredService<IConversationStateService>();
+                // state.SetState("agentId", fn.CurrentAgentId);
+            }
+
+            // Add to dialog history
+            _storage.Append(conversationId, preAgentId, fn);
+
+            // After function is executed, pass the result to LLM to get a natural response
+            wholeDialogs.Add(fn);
+
+            await GetChatCompletionsAsyncRecursively(chatCompletion, conversationId, agent, wholeDialogs, onMessageReceived, onFunctionExecuting);
+        });
+
+        return result;
+    }
+
+    private async Task HandleAssistantMessage(RoleDialogModel msg, Func<RoleDialogModel, Task> onMessageReceived)
+    {
+        var hooks = _services.GetServices<IConversationHook>().ToList();
+
+        // After chat completion hook
+        foreach (var hook in hooks)
+        {
+            await hook.AfterCompletion(msg);
+        }
+
+        await onMessageReceived(msg);
+    }
+
+    private async Task HandleFunctionMessage(RoleDialogModel msg, Func<RoleDialogModel, Task> onFunctionExecuting)
+    {
+        // Save states
+        SaveStateByArgs(msg.FunctionArgs);
+
+        // Call functions
+        await onFunctionExecuting(msg);
+        await CallFunctions(msg);
+    }
+}

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

@@ -0,0 +1,93 @@
+using BotSharp.Abstraction.Conversations.Models;
+using BotSharp.Abstraction.MLTasks;
+
+namespace BotSharp.Core.Conversations.Services;
+
+public partial class ConversationService
+{
+    public async Task<bool> SendMessage(string agentId, string conversationId,
+        RoleDialogModel lastDialog,
+        Func<RoleDialogModel, Task> onMessageReceived,
+        Func<RoleDialogModel, Task> onFunctionExecuting)
+    {
+        var converation = await GetConversation(conversationId);
+
+        // Create conversation if this conversation not exists
+        if (converation == null)
+        {
+            var sess = new Conversation
+            {
+                Id = conversationId,
+                AgentId = agentId
+            };
+            converation = await NewConversation(sess);
+        }
+
+        // conversation state
+        var stateService = _services.GetRequiredService<IConversationStateService>();
+        stateService.SetConversation(conversationId);
+        stateService.Load();
+
+        var router = _services.GetRequiredService<IAgentRouting>();
+        var agent = await router.LoadCurrentAgent();
+
+        _logger.LogInformation($"[{agent.Name}] {lastDialog.Role}: {lastDialog.Content}");
+
+        lastDialog.CurrentAgentId = agent.Id;
+        _storage.Append(conversationId, agent.Id, lastDialog);
+
+        var wholeDialogs = GetDialogHistory(conversationId);
+
+        // Get relevant domain knowledge
+        /*if (_settings.EnableKnowledgeBase)
+        {
+            var knowledge = _services.GetRequiredService<IKnowledgeService>();
+            agent.Knowledges = await knowledge.GetKnowledges(new KnowledgeRetrievalModel
+            {
+                AgentId = agentId,
+                Question = string.Join("\n", wholeDialogs.Select(x => x.Content))
+            });
+        }*/
+
+        var hooks = _services.GetServices<IConversationHook>().ToList();
+
+        // Before chat completion hook
+        foreach (var hook in hooks)
+        {
+            hook.SetAgent(agent)
+                .SetConversation(converation);
+
+            await hook.OnDialogsLoaded(wholeDialogs);
+            await hook.BeforeCompletion();
+        }
+
+        var chatCompletion = GetChatCompletion();
+        var result = await GetChatCompletionsAsyncRecursively(chatCompletion,
+            conversationId,
+            agent,
+            wholeDialogs,
+            onMessageReceived,
+            onFunctionExecuting);
+
+        return result;
+    }
+
+    private void SaveStateByArgs(string args)
+    {
+        var stateService = _services.GetRequiredService<IConversationStateService>();
+        var jo = JsonSerializer.Deserialize<object>(args);
+        if (jo is JsonElement root)
+        {
+            foreach (JsonProperty property in root.EnumerateObject())
+            {
+                stateService.SetState(property.Name, property.Value.ToString());
+            }
+        }
+    }
+
+    public IChatCompletion GetChatCompletion()
+    {
+        var completions = _services.GetServices<IChatCompletion>();
+        return completions.FirstOrDefault(x => x.GetType().FullName.EndsWith(_settings.ChatCompletion));
+    }
+}