feat: 增强会话管理和 Agent 服务

- 优化 session_handler 会话处理逻辑
- 增强 agent_service Agent 服务功能
- 新增 chat_repository 仓储方法
- 更新 agent_handler 和 chat_group_handler
- 更新数据模型 agent 和 chat_session

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/internal/service/agent_service.go

@@ -18,7 +18,7 @@ import (
 
 // AgentChatRequest Python Agent 对话请求
 type AgentChatRequest struct {
-	AgentID        int    `json:"agent_id"`
+	AgentID        string `json:"agent_id"` // 支持 UUID 字符串
 	Message        string `json:"message"`
 	UserID         int    `json:"user_id"`
 	SessionID      string `json:"session_id,omitempty"`
@@ -32,7 +32,7 @@ type AgentChatRequest struct {
 
 // AgentChatResponse Python Agent 对话响应
 type AgentChatResponse struct {
-	AgentID    int             `json:"agent_id"`
+	AgentID    string          `json:"agent_id"` // 支持 UUID 字符串
 	Response   string          `json:"response"`
 	ToolCalls  []interface{}   `json:"tool_calls"`
 	TokensUsed int            `json:"tokens_used"`
@@ -66,10 +66,11 @@ type AgentService struct {
 	client    *http.Client
 	modelRepo *repository.ModelRepository
 	agentRepo *repository.AgentRepository
+	chatRepo  *repository.ChatRepository
 }
 
 // NewAgentService 创建 Agent 服务
-func NewAgentService(pythonURL string, modelRepo *repository.ModelRepository, agentRepo *repository.AgentRepository) *AgentService {
+func NewAgentService(pythonURL string, modelRepo *repository.ModelRepository, agentRepo *repository.AgentRepository, chatRepo *repository.ChatRepository) *AgentService {
 	return &AgentService{
 		pythonURL: pythonURL,
 		client: &http.Client{
@@ -77,6 +78,7 @@ func NewAgentService(pythonURL string, modelRepo *repository.ModelRepository, ag
 		},
 		modelRepo: modelRepo,
 		agentRepo: agentRepo,
+		chatRepo:  chatRepo,
 	}
 }
 
@@ -195,16 +197,19 @@ func (s *AgentService) TeamChat(req TeamChatRequest) (*TeamChatResponse, error)
 }
 
 // ChatStream 流式对话
-func (s *AgentService) ChatStream(c interface{}, agentID int, message, sessionID, modelID string, userID int) error {
+func (s *AgentService) ChatStream(c interface{}, agentID string, message, sessionID, modelID string, userID int) error {
 	// 获取 gin.Context
 	ginCtx, ok := c.(*gin.Context)
 	if !ok {
 		return fmt.Errorf("invalid context type")
 	}
 
+	log.Printf("[ChatStream] Request: agentID=%s, message=%s, sessionID=%s, modelID=%s, userID=%d",
+		agentID, message, sessionID, modelID, userID)
+
 	// 初始化请求体
 	reqBody := map[string]interface{}{
-		"agent_id":   agentID,
+		"agent_id":   agentID, // 传递字符串类型的 agent_id，支持 UUID
 		"message":    message,
 		"user_id":    userID,
 		"session_id": sessionID,
@@ -267,8 +272,10 @@ func (s *AgentService) ChatStream(c interface{}, agentID int, message, sessionID
 	for {
 		n, err := resp.Body.Read(buf)
 		if n > 0 {
+			log.Printf("[ChatStream] Received %d bytes from Python", n)
 			_, writeErr := ginCtx.Writer.Write(buf[:n])
 			if writeErr != nil {
+				log.Printf("[ChatStream] Write error: %v", writeErr)
 				break
 			}
 			// 强制刷新到客户端
@@ -277,6 +284,7 @@ func (s *AgentService) ChatStream(c interface{}, agentID int, message, sessionID
 			}
 		}
 		if err != nil {
+			log.Printf("[ChatStream] Done reading from Python, err: %v", err)
 			break
 		}
 	}
@@ -300,9 +308,10 @@ type CreateAgentRequest struct {
 
 // CreateAgentResponse 创建智能体响应
 type CreateAgentResponse struct {
-	AgentID int    `json:"agent_id"`
-	Name    string `json:"name"`
-	Message string `json:"message"`
+	AgentID    int    `json:"agent_id"`    // 保留兼容性
+	AgentIDStr string `json:"agent_id_str"` // 返回实际的 UUID
+	Name       string `json:"name"`
+	Message    string `json:"message"`
 }
 
 // CreateAgent 创建智能体
@@ -329,6 +338,7 @@ func (s *AgentService) CreateAgent(req CreateAgentRequest, userID int) (*CreateA
 		Name:            req.Name,
 		Description:     req.Description,
 		OwnerID:         fmt.Sprintf("%d", userID),
+		Avatar:          req.Avatar,
 		Skills:          skills,
 		RoleDescription: req.Prompt,
 		ModelProvider:   req.ModelProvider,
@@ -347,13 +357,11 @@ func (s *AgentService) CreateAgent(req CreateAgentRequest, userID int) (*CreateA
 
 	log.Printf("[AgentService] Agent created in database: %s (ID: %s)", agent.Name, agent.ID)
 
-	// 解析 agent ID 为整数返回
-	agentIDInt := int(time.Now().Unix()) % 100000
-
+	// 返回数据库中实际的 Agent ID (UUID字符串)
 	return &CreateAgentResponse{
-		AgentID: agentIDInt,
-		Name:    agent.Name,
-		Message: "Agent created successfully",
+		AgentIDStr: agent.ID,
+		Name:       agent.Name,
+		Message:    "Agent created successfully",
 	}, nil
 }
 
@@ -429,6 +437,14 @@ func (s *AgentService) DeleteAgent(agentID string) error {
 		return fmt.Errorf("agent not found: %w", err)
 	}
 
+	// 先删除该智能体的所有会话和消息
+	if s.chatRepo != nil {
+		if err := s.chatRepo.DeleteSessionsByAgentID(agentID); err != nil {
+			log.Printf("[AgentService] DeleteAgent: failed to delete sessions: %v", err)
+			// 继续尝试删除 agent，不因为 session 删除失败而中止
+		}
+	}
+
 	if err := s.agentRepo.Delete(agentID); err != nil {
 		return fmt.Errorf("failed to delete agent: %w", err)
 	}
@@ -438,7 +454,7 @@ func (s *AgentService) DeleteAgent(agentID string) error {
 }
 
 // UpdateAgent 更新智能体
-func (s *AgentService) UpdateAgent(agentID, name, description string, skills []string, roleDescription, modelProvider, modelName string) error {
+func (s *AgentService) UpdateAgent(agentID, name, description, avatar string, skills []string, roleDescription, modelProvider, modelName string) error {
 	if s.agentRepo == nil {
 		return fmt.Errorf("agent repository not initialized")
 	}
@@ -458,6 +474,9 @@ func (s *AgentService) UpdateAgent(agentID, name, description string, skills []s
 	if description != "" {
 		agent.Description = description
 	}
+	if avatar != "" {
+		agent.Avatar = avatar
+	}
 	if skills != nil {
 		agent.Skills = skills
 	}