Refactor session management to support dialog-based architecture

- Removed InputHandler and related input event handling code.
- Updated GatewayState to handle new session commands for dialogs.
- Introduced UnifiedSessionId for managing session identifiers across channels and chats.
- Refactored Session and SessionManager to manage dialogs instead of sessions.
- Added methods for creating, listing, switching, renaming, archiving, and deleting dialogs.
- Updated storage functions to accommodate dialog IDs in persistent session management.
- Enhanced tests to cover new dialog functionalities and ensure stability.

src/bus/message.rs

@@ -164,6 +164,7 @@ pub struct InboundMessage {
     pub channel: String,
     pub sender_id: String,
     pub chat_id: String,
+    pub dialog_id: Option<String>,
     pub content: String,
     pub timestamp: i64,
     pub media: Vec<MediaItem>,
@@ -199,52 +200,20 @@ impl OutboundMessage {
     }
 }
 
-// ============================================================================
-// ControlInbound - Session management operations (CLI channel only)
-// ============================================================================
-
-/// Session management operations that flow through the control channel
-#[derive(Debug, Clone)]
-pub enum ControlInbound {
-    CreateSession { title: Option<String> },
-    ListSessions { include_archived: bool },
-    LoadSession { session_id: String },
-    RenameSession { session_id: String, title: String },
-    ArchiveSession { session_id: String },
-    DeleteSession { session_id: String },
-    ClearHistory { session_id: String },
-}
-
-// ============================================================================
-// ControlOutbound - Responses for control operations
-// ============================================================================
-
-/// Responses for session management operations
-#[derive(Debug, Clone)]
-pub enum ControlOutbound {
-    SessionCreated { session_id: String, title: String },
-    SessionList { sessions: Vec<crate::protocol::SessionSummary> },
-    SessionLoaded { session_id: String, title: String, message_count: i64 },
-    SessionRenamed { session_id: String, title: String },
-    SessionArchived { session_id: String },
-    SessionDeleted { session_id: String },
-    HistoryCleared { session_id: String },
-    Pong,
-    Error { code: String, message: String },
-}
-
 // ============================================================================
 // ControlMessage - Message for control channel (session management)
+// Uses SessionCommand from session module
 // ============================================================================
 
 use crate::channels::base::ChannelError;
+use crate::session::{SessionCommand, SessionEvent};
 use tokio::sync::mpsc;
 
 /// Control message containing a session operation and reply channel
 #[derive(Debug, Clone)]
 pub struct ControlMessage {
-    pub op: ControlInbound,
+    pub op: SessionCommand,
-    pub reply_tx: mpsc::Sender<Result<ControlOutbound, ChannelError>>,
+    pub reply_tx: mpsc::Sender<Result<SessionEvent, ChannelError>>,
 }
 
 // ============================================================================

src/bus/mod.rs

@@ -2,7 +2,7 @@ pub mod dispatcher;
 pub mod message;
 
 pub use dispatcher::OutboundDispatcher;
-pub use message::{ChatMessage, ContentBlock, ControlInbound, ControlMessage, ControlOutbound, InboundMessage, MediaItem, OutboundMessage};
+pub use message::{ChatMessage, ContentBlock, ControlMessage, InboundMessage, MediaItem, OutboundMessage};
 
 use std::sync::Arc;
 use tokio::sync::{mpsc, Mutex};

src/channels/cli_chat.rs

@@ -3,11 +3,17 @@ use async_trait::async_trait;
 use tokio::sync::{mpsc, Mutex};
 use uuid::Uuid;
 
-use crate::bus::{ControlInbound, ControlMessage, ControlOutbound, InboundMessage, MessageBus, OutboundMessage};
+use crate::bus::{ControlMessage, InboundMessage, MessageBus, OutboundMessage};
+use crate::session::{SessionCommand, SessionEvent, UnifiedSessionId};
 use crate::protocol::{parse_inbound, WsInbound, WsOutbound};
 
 use super::base::{Channel, ChannelError};
 
+/// Generate a short ID (8 characters) from a UUID
+fn short_id() -> String {
+    Uuid::new_v4().to_string()[..8].to_string()
+}
+
 // ============================================================================
 // Client - Connected CLI client
 // ============================================================================
@@ -36,6 +42,9 @@ impl CliChatChannel {
 
     /// Register a new client connection, returns (session_id, client)
     pub(crate) async fn register_client(&self, sender: mpsc::Sender<WsOutbound>) -> (String, Arc<Client>) {
+        // Generate connection ID (used as chat_id) - use short ID
+        let connection_id = short_id();
+
         let client = Arc::new(Client {
             sender,
             current_session_id: Mutex::new(None),
@@ -43,11 +52,12 @@ impl CliChatChannel {
         self.clients.lock().await.push(client.clone());
 
         // Create initial session via control message
-        let session_id = match self.create_session_via_control(None).await {
+        let session_id = match self.create_session_via_control(&connection_id, None).await {
             Ok(id) => id,
             Err(e) => {
                 tracing::error!(error = %e, "Failed to create initial session");
-                Uuid::new_v4().to_string()
+                // Fall back to old format for backward compatibility
+                connection_id.clone()
             }
         };
 
@@ -101,11 +111,11 @@ impl CliChatChannel {
 
         match inbound {
             WsInbound::UserInput { content, chat_id, .. } => {
-                let chat_id = chat_id.or(current_session_guard.clone()).unwrap_or_else(|| Uuid::new_v4().to_string());
+                let chat_id = chat_id.or(current_session_guard.clone()).unwrap_or_else(short_id);
 
                 // If no session, create one first
                 if current_session_guard.is_none() {
-                    let new_id = self.create_session_via_control(None).await?;
+                    let new_id = self.create_session_via_control(&chat_id, None).await?;
                     *current_session_guard = Some(new_id);
                 }
 
@@ -116,6 +126,7 @@ impl CliChatChannel {
                     channel: self.name().to_string(),
                     sender_id: "cli".to_string(),
                     chat_id: session_id.clone(),
+                    dialog_id: None, // Use default/current dialog
                     content,
                     timestamp: crate::bus::message::current_timestamp(),
                     media: Vec::new(),
@@ -131,13 +142,15 @@ impl CliChatChannel {
                     .ok_or_else(|| ChannelError::Other("No active session".to_string()))?;
 
                 let (reply_tx, mut reply_rx) = mpsc::channel(1);
+                let session_id = UnifiedSessionId::parse(&target)
+                    .ok_or_else(|| ChannelError::Other("Invalid session ID format".to_string()))?;
                 bus.publish_control(ControlMessage {
-                    op: ControlInbound::ClearHistory { session_id: target.clone() },
+                    op: SessionCommand::ClearHistory { session_id },
                     reply_tx,
                 }).await?;
 
                 match reply_rx.recv().await {
-                    Some(Ok(ControlOutbound::HistoryCleared { .. })) => {
+                    Some(Ok(SessionEvent::HistoryCleared { .. })) => {
                         let _ = client
                             .sender
                             .send(WsOutbound::HistoryCleared { session_id: target })
@@ -155,7 +168,10 @@ impl CliChatChannel {
                 }
             }
             WsInbound::CreateSession { title } => {
-                let new_id = self.create_session_via_control(title.as_deref()).await?;
+                // Use current session's chat_id if available, otherwise generate new one
+                let chat_id = current_session_guard.clone()
+                    .unwrap_or_else(short_id);
+                let new_id = self.create_session_via_control(&chat_id, title.as_deref()).await?;
                 *current_session_guard = Some(new_id.clone());
                 let _ = client
                     .sender
@@ -166,19 +182,42 @@ impl CliChatChannel {
                     .await;
             }
             WsInbound::ListSessions { include_archived } => {
+                // List dialogs for the current chat
+                let chat_id = current_session_guard.clone()
+                    .unwrap_or_else(|| "".to_string());
+                let chat_id_for_response = chat_id.clone();
                 let (reply_tx, mut reply_rx) = mpsc::channel(1);
                 bus.publish_control(ControlMessage {
-                    op: ControlInbound::ListSessions { include_archived },
+                    op: SessionCommand::ListDialogs {
+                        channel: "cli_chat".to_string(),
+                        chat_id,
+                        include_archived,
+                    },
                     reply_tx,
                 }).await?;
 
                 match reply_rx.recv().await {
-                    Some(Ok(ControlOutbound::SessionList { sessions })) => {
+                    Some(Ok(SessionEvent::DialogList { dialogs, current_dialog_id })) => {
+                        // Convert DialogInfo to SessionSummary for backward compatibility
+                        let sessions: Vec<crate::protocol::SessionSummary> = dialogs.into_iter().map(|d| {
+                            crate::protocol::SessionSummary {
+                                session_id: d.session_id.to_string(),
+                                title: d.title,
+                                channel_name: d.session_id.channel.clone(),
+                                chat_id: d.session_id.chat_id,
+                                message_count: d.message_count,
+                                last_active_at: d.last_active_at,
+                                archived_at: d.archived_at,
+                            }
+                        }).collect();
+                        let current_session_id = current_dialog_id.map(|did| {
+                            UnifiedSessionId::new("cli_chat", chat_id_for_response.clone(), did).to_string()
+                        });
                         let _ = client
                             .sender
                             .send(WsOutbound::SessionList {
                                 sessions,
-                                current_session_id: current_session_guard.clone(),
+                                current_session_id,
                             })
                             .await;
                     }
@@ -194,28 +233,44 @@ impl CliChatChannel {
                 }
             }
             WsInbound::LoadSession { session_id } => {
+                // LoadSession: parse the session_id and get current dialog info
                 let (reply_tx, mut reply_rx) = mpsc::channel(1);
+                let unified_id = UnifiedSessionId::parse(&session_id)
+                    .ok_or_else(|| ChannelError::Other("Invalid session ID format".to_string()))?;
                 bus.publish_control(ControlMessage {
-                    op: ControlInbound::LoadSession { session_id: session_id.clone() },
+                    op: SessionCommand::GetCurrentDialog {
+                        channel: unified_id.channel.clone(),
+                        chat_id: unified_id.chat_id.clone(),
+                    },
                     reply_tx,
                 }).await?;
 
                 match reply_rx.recv().await {
-                    Some(Ok(ControlOutbound::SessionLoaded { session_id, title, message_count })) => {
+                    Some(Ok(SessionEvent::CurrentDialog { session_id: current_session_id_opt })) => {
-                        *current_session_guard = Some(session_id.clone());
+                        if let Some(current_session_id) = current_session_id_opt {
+                            *current_session_guard = Some(current_session_id.to_string());
                             let _ = client
                                 .sender
                                 .send(WsOutbound::SessionLoaded {
-                                session_id,
+                                    session_id: current_session_id.to_string(),
-                                title,
+                                    title: "Session".to_string(), // TODO: get actual title
-                                message_count,
+                                    message_count: 0, // TODO: get actual count
                                 })
                                 .await;
+                        } else {
+                            let _ = client
+                                .sender
+                                .send(WsOutbound::Error {
+                                    code: "NO_CURRENT_DIALOG".to_string(),
+                                    message: "No current dialog".to_string(),
+                                })
+                                .await;
+                        }
                     }
                     Some(Ok(_)) => {
                         // Unexpected response type
                     }
-                    Some(Err(e)) => {
+                    Some(Err(_e)) => {
                         let _ = client
                             .sender
                             .send(WsOutbound::Error {
@@ -235,16 +290,18 @@ impl CliChatChannel {
                 })?;
 
                 let (reply_tx, mut reply_rx) = mpsc::channel(1);
+                let unified_id = UnifiedSessionId::parse(&target)
+                    .ok_or_else(|| ChannelError::Other("Invalid session ID format".to_string()))?;
                 bus.publish_control(ControlMessage {
-                    op: ControlInbound::RenameSession { session_id: target.clone(), title: title.clone() },
+                    op: SessionCommand::RenameDialog { session_id: unified_id, title: title.clone() },
                     reply_tx,
                 }).await?;
 
                 match reply_rx.recv().await {
-                    Some(Ok(ControlOutbound::SessionRenamed { session_id, title })) => {
+                    Some(Ok(SessionEvent::DialogRenamed { session_id, title })) => {
                         let _ = client
                             .sender
-                            .send(WsOutbound::SessionRenamed { session_id, title })
+                            .send(WsOutbound::SessionRenamed { session_id: session_id.to_string(), title })
                             .await;
                     }
                     Some(Ok(_)) => {
@@ -264,16 +321,18 @@ impl CliChatChannel {
                 })?;
 
                 let (reply_tx, mut reply_rx) = mpsc::channel(1);
+                let unified_id = UnifiedSessionId::parse(&target)
+                    .ok_or_else(|| ChannelError::Other("Invalid session ID format".to_string()))?;
                 bus.publish_control(ControlMessage {
-                    op: ControlInbound::ArchiveSession { session_id: target.clone() },
+                    op: SessionCommand::ArchiveDialog { session_id: unified_id },
                     reply_tx,
                 }).await?;
 
                 match reply_rx.recv().await {
-                    Some(Ok(ControlOutbound::SessionArchived { session_id })) => {
+                    Some(Ok(SessionEvent::DialogArchived { session_id })) => {
                         let _ = client
                             .sender
-                            .send(WsOutbound::SessionArchived { session_id })
+                            .send(WsOutbound::SessionArchived { session_id: session_id.to_string() })
                             .await;
                     }
                     Some(Ok(_)) => {
@@ -293,22 +352,24 @@ impl CliChatChannel {
                 })?;
 
                 let (reply_tx, mut reply_rx) = mpsc::channel(1);
+                let unified_id = UnifiedSessionId::parse(&target)
+                    .ok_or_else(|| ChannelError::Other("Invalid session ID format".to_string()))?;
                 bus.publish_control(ControlMessage {
-                    op: ControlInbound::DeleteSession { session_id: target.clone() },
+                    op: SessionCommand::DeleteDialog { session_id: unified_id },
                     reply_tx,
                 }).await?;
 
                 match reply_rx.recv().await {
-                    Some(Ok(ControlOutbound::SessionDeleted { session_id })) => {
+                    Some(Ok(SessionEvent::DialogDeleted { session_id })) => {
                         let _ = client
                             .sender
-                            .send(WsOutbound::SessionDeleted { session_id: session_id.clone() })
+                            .send(WsOutbound::SessionDeleted { session_id: session_id.to_string() })
                             .await;
 
                         // If deleting current session, create a new one
                         if current_session_guard.as_deref() == Some(&target) {
                             drop(reply_rx);
-                            if let Ok(new_id) = self.create_session_via_control(None).await {
+                            if let Ok(new_id) = self.create_session_via_control(&target, None).await {
                                 *current_session_guard = Some(new_id.clone());
                                 let _ = client
                                     .sender
@@ -339,7 +400,7 @@ impl CliChatChannel {
     }
 
     /// Create a session via control message and return the session_id
-    async fn create_session_via_control(&self, title: Option<&str>) -> Result<String, ChannelError> {
+    async fn create_session_via_control(&self, connection_id: &str, title: Option<&str>) -> Result<String, ChannelError> {
         let bus = {
             let guard = self.bus.lock().unwrap();
             guard.clone().ok_or_else(|| ChannelError::Other("Channel not started".to_string()))?
@@ -347,13 +408,17 @@ impl CliChatChannel {
 
         let (reply_tx, mut reply_rx) = mpsc::channel(1);
         bus.publish_control(ControlMessage {
-            op: ControlInbound::CreateSession { title: title.map(String::from) },
+            op: SessionCommand::CreateDialog {
+                channel: "cli_chat".to_string(),
+                chat_id: connection_id.to_string(),
+                title: title.map(String::from),
+            },
             reply_tx,
         }).await?;
 
         match reply_rx.recv().await {
-            Some(Ok(ControlOutbound::SessionCreated { session_id, .. })) => {
+            Some(Ok(SessionEvent::DialogCreated { session_id, .. })) => {
-                Ok(session_id)
+                Ok(session_id.to_string())
             }
             Some(Ok(_)) => {
                 Err(ChannelError::Other("Unexpected response type".to_string()))
@@ -388,7 +453,7 @@ impl Channel for CliChatChannel {
         let clients = self.clients.lock().await.clone();
         for client in clients {
             let outbound = WsOutbound::AssistantResponse {
-                id: Uuid::new_v4().to_string(),
+                id: short_id(),
                 content: msg.content.clone(),
                 role: "assistant".to_string(),
             };

src/channels/feishu.rs

@@ -1106,6 +1106,7 @@ impl FeishuChannel {
                                                 channel: "feishu".to_string(),
                                                 sender_id: parsed.open_id.clone(),
                                                 chat_id: parsed.chat_id.clone(),
+                                                dialog_id: None, // Use default/current dialog
                                                 content: parsed.content.clone(),
                                                 timestamp: crate::bus::message::current_timestamp(),
                                                 media: parsed.media.map(|m| vec![m]).unwrap_or_default(),

src/client/channel.rs

@@ -1,50 +0,0 @@
-use tokio::io::{AsyncBufReadExt, BufReader, AsyncWriteExt};
-
-pub struct CliChannel {
-    read: BufReader<tokio::io::Stdin>,
-    write: tokio::io::Stdout,
-}
-
-impl CliChannel {
-    pub fn new() -> Self {
-        Self {
-            read: BufReader::new(tokio::io::stdin()),
-            write: tokio::io::stdout(),
-        }
-    }
-
-    pub async fn read_line(&mut self, prompt: &str) -> Result<Option<String>, std::io::Error> {
-        print!("{}", prompt);
-        self.write.flush().await?;
-
-        let mut line = String::new();
-        let bytes_read = self.read.read_line(&mut line).await?;
-
-        if bytes_read == 0 {
-            return Ok(None);
-        }
-
-        Ok(Some(line.trim_end().to_string()))
-    }
-
-    pub async fn write_line(&mut self, content: &str) -> Result<(), std::io::Error> {
-        self.write.write_all(content.as_bytes()).await?;
-        self.write.write_all(b"\n").await?;
-        self.write.flush().await
-    }
-
-    pub async fn write_response(&mut self, content: &str) -> Result<(), std::io::Error> {
-        for line in content.lines() {
-            self.write.write_all(b"  ").await?;
-            self.write.write_all(line.as_bytes()).await?;
-            self.write.write_all(b"\n").await?;
-        }
-        self.write.flush().await
-    }
-}
-
-impl Default for CliChannel {
-    fn default() -> Self {
-        Self::new()
-    }
-}

src/client/input.rs

@@ -1,127 +0,0 @@
-use super::channel::CliChannel;
-
-pub enum InputEvent {
-    Message(String),
-    Command(InputCommand),
-}
-
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub enum InputCommand {
-    Exit,
-    Clear,
-    New(Option<String>),
-    Sessions,
-    Use(String),
-    Rename(String),
-    Archive,
-    Delete,
-}
-
-pub struct InputHandler {
-    channel: CliChannel,
-}
-
-impl InputHandler {
-    pub fn new() -> Self {
-        Self {
-            channel: CliChannel::new(),
-        }
-    }
-
-    pub async fn read_input(&mut self, prompt: &str) -> Result<Option<InputEvent>, InputError> {
-        match self.channel.read_line(prompt).await {
-            Ok(Some(line)) => {
-                if line.trim().is_empty() {
-                    return Ok(None);
-                }
-
-                if let Some(cmd) = self.handle_special_commands(&line) {
-                    return Ok(Some(InputEvent::Command(cmd)));
-                }
-
-                Ok(Some(InputEvent::Message(line)))
-            }
-            Ok(None) => Ok(None),
-            Err(e) => Err(InputError::IoError(e)),
-        }
-    }
-
-    pub async fn write_output(&mut self, content: &str) -> Result<(), InputError> {
-        self.channel.write_line(content).await.map_err(InputError::IoError)
-    }
-
-    pub async fn write_response(&mut self, content: &str) -> Result<(), InputError> {
-        self.channel.write_response(content).await.map_err(InputError::IoError)
-    }
-
-    fn handle_special_commands(&self, line: &str) -> Option<InputCommand> {
-        let trimmed = line.trim();
-        let mut parts = trimmed.splitn(2, char::is_whitespace);
-        let command = parts.next()?;
-        let arg = parts.next().map(str::trim).filter(|value| !value.is_empty());
-
-        match command {
-            "/quit" | "/exit" | "/q" => Some(InputCommand::Exit),
-            "/clear" => Some(InputCommand::Clear),
-            "/new" => Some(InputCommand::New(arg.map(ToOwned::to_owned))),
-            "/sessions" => Some(InputCommand::Sessions),
-            "/use" => arg.map(|value| InputCommand::Use(value.to_string())),
-            "/rename" => arg.map(|value| InputCommand::Rename(value.to_string())),
-            "/archive" => Some(InputCommand::Archive),
-            "/delete" => Some(InputCommand::Delete),
-            _ => None,
-        }
-    }
-}
-
-impl Default for InputHandler {
-    fn default() -> Self {
-        Self::new()
-    }
-}
-
-#[derive(Debug)]
-pub enum InputError {
-    IoError(std::io::Error),
-}
-
-impl std::fmt::Display for InputError {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        match self {
-            InputError::IoError(e) => write!(f, "IO error: {}", e),
-        }
-    }
-}
-
-impl std::error::Error for InputError {}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_special_command_parsing() {
-        let handler = InputHandler::new();
-
-        assert_eq!(handler.handle_special_commands("/quit"), Some(InputCommand::Exit));
-        assert_eq!(handler.handle_special_commands("/clear"), Some(InputCommand::Clear));
-        assert_eq!(handler.handle_special_commands("/new"), Some(InputCommand::New(None)));
-        assert_eq!(
-            handler.handle_special_commands("/new planning"),
-            Some(InputCommand::New(Some("planning".to_string())))
-        );
-        assert_eq!(handler.handle_special_commands("/sessions"), Some(InputCommand::Sessions));
-        assert_eq!(
-            handler.handle_special_commands("/use abc123"),
-            Some(InputCommand::Use("abc123".to_string()))
-        );
-        assert_eq!(
-            handler.handle_special_commands("/rename project alpha"),
-            Some(InputCommand::Rename("project alpha".to_string()))
-        );
-        assert_eq!(handler.handle_special_commands("/archive"), Some(InputCommand::Archive));
-        assert_eq!(handler.handle_special_commands("/delete"), Some(InputCommand::Delete));
-        assert_eq!(handler.handle_special_commands("/unknown"), None);
-        assert_eq!(handler.handle_special_commands("/use"), None);
-    }
-}

src/gateway/mod.rs

@@ -5,12 +5,11 @@ use std::sync::Arc;
 use axum::{routing, Router};
 use tokio::net::TcpListener;
 
-use crate::bus::{ControlInbound, ControlMessage, ControlOutbound, OutboundDispatcher};
+use crate::bus::{ControlMessage, OutboundDispatcher};
 use crate::channels::{ChannelManager, CliChatChannel};
 use crate::channels::base::{Channel, ChannelError};
 use crate::config::Config;
 use crate::logging;
-use crate::protocol::SessionSummary;
 use crate::session::SessionManager;
 
 pub struct GatewayState {
@@ -94,6 +93,7 @@ impl GatewayState {
                             &inbound.channel,
                             &inbound.sender_id,
                             &inbound.chat_id,
+                            inbound.dialog_id.as_deref(),
                             &inbound.content,
                             inbound.media,
                         ).await {
@@ -138,59 +138,52 @@ impl GatewayState {
         session_manager: &SessionManager,
         msg: ControlMessage,
     ) {
+        use crate::session::{SessionCommand::*, SessionEvent};
+
         let reply_tx = msg.reply_tx;
-        let result = match msg.op {
+        let result: Result<SessionEvent, ChannelError> = match msg.op {
-            ControlInbound::CreateSession { title } => {
+            CreateDialog { channel, chat_id, title } => {
-                session_manager.create_cli_session(title.as_deref())
+                session_manager.create_dialog(&channel, &chat_id, title.as_deref()).await
-                    .map(|record| ControlOutbound::SessionCreated {
+                    .map(|(session_id, title)| SessionEvent::DialogCreated { session_id, title })
-                        session_id: record.id,
+                    .map_err(|e| ChannelError::Other(e.to_string()))
-                        title: record.title,
-                    })
             }
-            ControlInbound::ListSessions { include_archived } => {
+            ListDialogs { channel, chat_id, include_archived } => {
-                session_manager.list_cli_sessions(include_archived)
+                session_manager.list_dialogs(&channel, &chat_id, include_archived).await
-                    .map(|records| ControlOutbound::SessionList {
+                    .map(|(dialogs, current_dialog_id)| SessionEvent::DialogList { dialogs, current_dialog_id })
-                        sessions: records.into_iter().map(|r| SessionSummary {
+                    .map_err(|e| ChannelError::Other(e.to_string()))
-                            session_id: r.id,
-                            title: r.title,
-                            channel_name: r.channel_name,
-                            chat_id: r.chat_id,
-                            message_count: r.message_count,
-                            last_active_at: r.last_active_at,
-                            archived_at: r.archived_at,
-                        }).collect()
-                    })
             }
-            ControlInbound::LoadSession { session_id } => {
+            GetCurrentDialog { channel, chat_id } => {
-                session_manager.get_session_record(&session_id)
+                session_manager.get_current_dialog(&channel, &chat_id).await
-                    .map(|opt| opt.map(|r| ControlOutbound::SessionLoaded {
+                    .map(|session_id| SessionEvent::CurrentDialog { session_id })
-                        session_id: r.id,
+                    .map_err(|e| ChannelError::Other(e.to_string()))
-                        title: r.title,
-                        message_count: r.message_count,
-                    }).unwrap_or_else(|| ControlOutbound::Error {
-                        code: "SESSION_NOT_FOUND".to_string(),
-                        message: format!("Session not found: {}", session_id),
-                    }))
             }
-            ControlInbound::RenameSession { session_id, title } => {
+            SwitchDialog { channel, chat_id, dialog_id } => {
-                session_manager.rename_session(&session_id, &title)
+                session_manager.switch_dialog(&channel, &chat_id, &dialog_id).await
-                    .map(|()| ControlOutbound::SessionRenamed { session_id, title })
+                    .map(|session_id| SessionEvent::DialogSwitched { session_id })
+                    .map_err(|e| ChannelError::Other(e.to_string()))
             }
-            ControlInbound::ArchiveSession { session_id } => {
+            RenameDialog { session_id, title } => {
-                session_manager.archive_session(&session_id)
+                session_manager.rename_dialog(&session_id, &title)
-                    .map(|()| ControlOutbound::SessionArchived { session_id })
+                    .map(|()| SessionEvent::DialogRenamed { session_id, title })
+                    .map_err(|e| ChannelError::Other(e.to_string()))
             }
-            ControlInbound::DeleteSession { session_id } => {
+            ArchiveDialog { session_id } => {
-                session_manager.delete_session(&session_id)
+                session_manager.archive_dialog(&session_id)
-                    .map(|()| ControlOutbound::SessionDeleted { session_id })
+                    .map(|()| SessionEvent::DialogArchived { session_id })
+                    .map_err(|e| ChannelError::Other(e.to_string()))
             }
-            ControlInbound::ClearHistory { session_id } => {
+            DeleteDialog { session_id } => {
-                session_manager.clear_session_messages(&session_id)
+                session_manager.delete_dialog(&session_id)
-                    .map(|()| ControlOutbound::HistoryCleared { session_id })
+                    .map(|()| SessionEvent::DialogDeleted { session_id })
+                    .map_err(|e| ChannelError::Other(e.to_string()))
+            }
+            ClearHistory { session_id } => {
+                session_manager.clear_dialog_history(&session_id)
+                    .map(|()| SessionEvent::HistoryCleared { session_id })
+                    .map_err(|e| ChannelError::Other(e.to_string()))
             }
         };
 
-        let result = result.map_err(|e| ChannelError::Other(e.to_string()));
         let _ = reply_tx.send(result).await;
     }
 }

src/session/commands.rs

@@ -1,11 +1,66 @@
+use super::session_id::UnifiedSessionId;
+
 /// Session management commands issued by Channel to SessionManager
 #[derive(Debug, Clone)]
 pub enum SessionCommand {
-    CreateSession { title: Option<String> },
+    /// Create a new dialog in the given chat
-    ListSessions { include_archived: bool },
+    CreateDialog {
-    LoadSession { session_id: String },
+        channel: String,
-    RenameSession { session_id: String, title: String },
+        chat_id: String,
-    ArchiveSession { session_id: String },
+        title: Option<String>,
-    DeleteSession { session_id: String },
+    },
-    ClearHistory { session_id: String },
+    /// List all dialogs in a chat
+    ListDialogs {
+        channel: String,
+        chat_id: String,
+        include_archived: bool,
+    },
+    /// Switch to a specific dialog (set as current)
+    SwitchDialog {
+        channel: String,
+        chat_id: String,
+        dialog_id: String,
+    },
+    /// Get the current dialog for a chat
+    GetCurrentDialog {
+        channel: String,
+        chat_id: String,
+    },
+    /// Rename a dialog
+    RenameDialog {
+        session_id: UnifiedSessionId,
+        title: String,
+    },
+    /// Archive a dialog
+    ArchiveDialog {
+        session_id: UnifiedSessionId,
+    },
+    /// Delete a dialog
+    DeleteDialog {
+        session_id: UnifiedSessionId,
+    },
+    /// Clear dialog history
+    ClearHistory {
+        session_id: UnifiedSessionId,
+    },
+}
+
+impl SessionCommand {
+    /// Create a CreateDialog command
+    pub fn create_dialog(channel: impl Into<String>, chat_id: impl Into<String>, title: Option<String>) -> Self {
+        Self::CreateDialog {
+            channel: channel.into(),
+            chat_id: chat_id.into(),
+            title,
+        }
+    }
+
+    /// Create a ListDialogs command
+    pub fn list_dialogs(channel: impl Into<String>, chat_id: impl Into<String>, include_archived: bool) -> Self {
+        Self::ListDialogs {
+            channel: channel.into(),
+            chat_id: chat_id.into(),
+            include_archived,
+        }
+    }
 }

src/session/events.rs

@@ -1,14 +1,57 @@
-use crate::protocol::SessionSummary;
+use super::session_id::UnifiedSessionId;
+
+/// Dialog information returned by SessionManager
+#[derive(Debug, Clone)]
+pub struct DialogInfo {
+    pub session_id: UnifiedSessionId,
+    pub title: String,
+    pub created_at: i64,
+    pub last_active_at: i64,
+    pub message_count: i64,
+    pub archived_at: Option<i64>,
+}
 
 /// Session events emitted by SessionManager to Channel
 #[derive(Debug, Clone)]
 pub enum SessionEvent {
-    SessionCreated { session_id: String, title: String },
+    /// A new dialog was created
-    SessionList { sessions: Vec<SessionSummary> },
+    DialogCreated {
-    SessionLoaded { session_id: String, title: String, message_count: i64 },
+        session_id: UnifiedSessionId,
-    SessionRenamed { session_id: String, title: String },
+        title: String,
-    SessionArchived { session_id: String },
+    },
-    SessionDeleted { session_id: String },
+    /// List of dialogs returned
-    HistoryCleared { session_id: String },
+    DialogList {
-    Error { code: String, message: String },
+        dialogs: Vec<DialogInfo>,
+        current_dialog_id: Option<String>,
+    },
+    /// Current dialog info returned
+    CurrentDialog {
+        session_id: Option<UnifiedSessionId>,
+    },
+    /// Dialog switched successfully
+    DialogSwitched {
+        session_id: UnifiedSessionId,
+    },
+    /// Dialog renamed
+    DialogRenamed {
+        session_id: UnifiedSessionId,
+        title: String,
+    },
+    /// Dialog archived
+    DialogArchived {
+        session_id: UnifiedSessionId,
+    },
+    /// Dialog deleted
+    DialogDeleted {
+        session_id: UnifiedSessionId,
+    },
+    /// Dialog history cleared
+    HistoryCleared {
+        session_id: UnifiedSessionId,
+    },
+    /// Error occurred
+    Error {
+        code: String,
+        message: String,
+    },
 }

src/session/mod.rs

@@ -2,9 +2,10 @@ pub mod error;
 pub mod commands;
 pub mod events;
 pub mod session;
+pub mod session_id;
 
 pub use error::SessionError;
 pub use commands::SessionCommand;
-pub use events::SessionEvent;
+pub use events::{SessionEvent, DialogInfo};
-
 pub use session::{Session, SessionManager};
+pub use session_id::UnifiedSessionId;

src/session/session.rs

@@ -8,19 +8,24 @@ use crate::config::LLMProviderConfig;
 use crate::agent::{AgentLoop, AgentError, ContextCompressor};
 use crate::protocol::WsOutbound;
 use crate::providers::{create_provider, LLMProvider};
-use crate::storage::{SessionRecord, SessionStore, persistent_session_id};
+use crate::session::session_id::{UnifiedSessionId, DEFAULT_DIALOG_ID};
+use crate::session::events::DialogInfo;
+use crate::storage::{SessionRecord, SessionStore};
 use crate::tools::{
     BashTool, CalculatorTool, FileEditTool, FileReadTool, FileWriteTool,
     HttpRequestTool, ToolRegistry, WebFetchTool,
 };
 
-/// Session 按 channel 隔离，每个 channel 一个 Session
+/// Generate a short ID (8 characters) from a UUID
-/// History 按 chat_id 隔离，由 Session 统一管理
+fn short_id() -> String {
+    Uuid::new_v4().to_string()[..8].to_string()
+}
+
+/// Session = 一个 dialog
+/// 每个 Session 对应一个 UnifiedSessionId，有独立的 messages history
 pub struct Session {
-    pub id: Uuid,
+    pub id: UnifiedSessionId,
-    pub channel_name: String,
+    messages: Vec<ChatMessage>,
-    /// 按 chat_id 路由到不同会话历史，支持多用户多会话
-    chat_histories: HashMap<String, Vec<ChatMessage>>,
     pub user_tx: mpsc::Sender<WsOutbound>,
     provider_config: LLMProviderConfig,
     provider: Arc<dyn LLMProvider>,
@@ -31,7 +36,7 @@ pub struct Session {
 
 impl Session {
     pub async fn new(
-        channel_name: String,
+        id: UnifiedSessionId,
         provider_config: LLMProviderConfig,
         user_tx: mpsc::Sender<WsOutbound>,
         tools: Arc<ToolRegistry>,
@@ -42,9 +47,8 @@ impl Session {
         let provider: Arc<dyn LLMProvider> = Arc::from(provider_box);
 
         Ok(Self {
-            id: Uuid::new_v4(),
+            id,
-            channel_name,
+            messages: Vec::new(),
-            chat_histories: HashMap::new(),
             user_tx,
             provider_config: provider_config.clone(),
             provider: provider.clone(),
@@ -54,93 +58,83 @@ impl Session {
         })
     }
 
-    pub fn persistent_session_id(&self, chat_id: &str) -> String {
+    /// 获取持久化 session ID
-        persistent_session_id(&self.channel_name, chat_id)
+    pub fn persistent_session_id(&self) -> String {
+        self.id.to_string()
     }
 
-    pub fn ensure_persistent_session(&self, chat_id: &str) -> Result<SessionRecord, AgentError> {
+    /// 确保存储中有此 session
+    pub fn ensure_persistent_session(&self) -> Result<SessionRecord, AgentError> {
         self.store
-            .ensure_channel_session(&self.channel_name, chat_id)
+            .ensure_channel_session(&self.id.channel, &self.id.chat_id, &self.id.dialog_id)
             .map_err(|err| AgentError::Other(format!("session persistence error: {}", err)))
     }
 
-    pub fn ensure_chat_loaded(&mut self, chat_id: &str) -> Result<(), AgentError> {
+    /// 加载历史消息到内存
-        if self.chat_histories.contains_key(chat_id) {
+    pub fn load_history(&mut self) -> Result<(), AgentError> {
+        if !self.messages.is_empty() {
             return Ok(());
         }
-
+        let history = self.store
-        let history = self
+            .load_messages(&self.persistent_session_id())
-            .store
-            .load_messages(&self.persistent_session_id(chat_id))
             .map_err(|err| AgentError::Other(format!("session history load error: {}", err)))?;
-        self.chat_histories.insert(chat_id.to_string(), history);
+        self.messages = history;
         Ok(())
     }
 
-    /// 获取或创建指定 chat_id 的会话历史
+    /// 添加消息到历史
-    pub fn get_or_create_history(&mut self, chat_id: &str) -> &mut Vec<ChatMessage> {
+    pub fn add_message(&mut self, message: ChatMessage) {
-        self.chat_histories
+        self.messages.push(message);
-            .entry(chat_id.to_string())
-            .or_insert_with(Vec::new)
     }
 
-    /// 获取指定 chat_id 的会话历史（不创建）
+    /// 获取消息历史
-    pub fn get_history(&self, chat_id: &str) -> Option<&Vec<ChatMessage>> {
+    pub fn get_history(&self) -> &[ChatMessage] {
-        self.chat_histories.get(chat_id)
+        &self.messages
     }
 
-    /// 使用完整消息追加到历史
+    /// 清除历史消息
-    pub fn add_message(&mut self, chat_id: &str, message: ChatMessage) {
+    pub fn clear_history(&mut self) -> Result<(), AgentError> {
-        let history = self.get_or_create_history(chat_id);
+        let len = self.messages.len();
-        history.push(message);
+        self.messages.clear();
-    }
-
-    pub fn remove_history(&mut self, chat_id: &str) {
-        self.chat_histories.remove(chat_id);
-    }
-
-    pub fn clear_chat_history(&mut self, chat_id: &str) -> Result<(), AgentError> {
-        if let Some(history) = self.chat_histories.get_mut(chat_id) {
-            let len = history.len();
-            history.clear();
         #[cfg(debug_assertions)]
-            tracing::debug!(chat_id = %chat_id, previous_len = len, "Chat history cleared");
+        tracing::debug!(session_id = %self.id, previous_len = len, "Chat history cleared");
-        }
-
         self.store
-            .clear_messages(&self.persistent_session_id(chat_id))
+            .clear_messages(&self.persistent_session_id())
-            .map_err(|err| AgentError::Other(format!("clear history persistence error: {}", err)))
+            .map_err(|err| AgentError::Other(format!("clear history error: {}", err)))
     }
 
-    pub fn reset_chat_context(&mut self, chat_id: &str) -> Result<(), AgentError> {
+    /// 重置对话上下文
-        if let Some(history) = self.chat_histories.get_mut(chat_id) {
+    pub fn reset_context(&mut self) -> Result<(), AgentError> {
-            let len = history.len();
+        let len = self.messages.len();
-            history.clear();
+        self.messages.clear();
         #[cfg(debug_assertions)]
-            tracing::debug!(chat_id = %chat_id, previous_len = len, "Chat history reset in memory");
+        tracing::debug!(session_id = %self.id, previous_len = len, "Chat context reset in memory");
-        }
-
         self.store
-            .reset_session(&self.persistent_session_id(chat_id))
+            .reset_session(&self.persistent_session_id())
-            .map_err(|err| AgentError::Other(format!("reset history persistence error: {}", err)))
+            .map_err(|err| AgentError::Other(format!("reset context error: {}", err)))
     }
 
-    /// 将消息写入内存与持久化层
+    /// Archive 此 session
-    pub fn append_persisted_message(&mut self, chat_id: &str, message: ChatMessage) -> Result<(), AgentError> {
+    pub fn archive(&self) -> Result<(), AgentError> {
-        let session_id = self.persistent_session_id(chat_id);
         self.store
-            .append_message(&session_id, &message)
+            .archive_session(&self.persistent_session_id())
-            .map_err(|err| AgentError::Other(format!("append message persistence error: {}", err)))?;
+            .map_err(|err| AgentError::Other(format!("archive session error: {}", err)))
-        self.add_message(chat_id, message);
-        Ok(())
     }
 
-    pub fn append_persisted_messages<I>(&mut self, chat_id: &str, messages: I) -> Result<(), AgentError>
+    /// 持久化消息
+    pub fn append_message(&self, message: &ChatMessage) -> Result<(), AgentError> {
+        self.store
+            .append_message(&self.persistent_session_id(), message)
+            .map_err(|err| AgentError::Other(format!("append message error: {}", err)))
+    }
+
+    /// 持久化多条消息
+    pub fn append_messages<I>(&self, messages: I) -> Result<(), AgentError>
     where
         I: IntoIterator<Item = ChatMessage>,
     {
         for message in messages {
-            self.append_persisted_message(chat_id, message)?;
+            self.append_message(&message)?;
         }
         Ok(())
     }
@@ -153,23 +147,6 @@ impl Session {
         }
     }
 
-    /// 清除所有历史
-    pub fn clear_all_history(&mut self) -> Result<(), AgentError> {
-        let chat_ids: Vec<String> = self.chat_histories.keys().cloned().collect();
-        let total: usize = self.chat_histories.values().map(|h| h.len()).sum();
-        self.chat_histories.clear();
-        #[cfg(debug_assertions)]
-        tracing::debug!(previous_total = total, "All chat histories cleared");
-
-        for chat_id in chat_ids {
-            self.store
-                .clear_messages(&self.persistent_session_id(&chat_id))
-                .map_err(|err| AgentError::Other(format!("clear history persistence error: {}", err)))?;
-        }
-
-        Ok(())
-    }
-
     pub async fn send(&self, msg: WsOutbound) {
         let _ = self.user_tx.send(msg).await;
     }
@@ -204,6 +181,7 @@ pub struct SessionManager {
 }
 
 struct SessionManagerInner {
+    /// Sessions keyed by UnifiedSessionId.to_string()
     sessions: HashMap<String, Arc<Mutex<Session>>>,
     session_timestamps: HashMap<String, Instant>,
     session_ttl: Duration,
@@ -238,15 +216,19 @@ fn parse_in_chat_command(content: &str) -> Option<InChatCommand> {
     }
 }
 
+/// Handle in-chat commands like /reset
+/// Returns Some(new_dialog_id) if FreshConversation was triggered
 pub(crate) fn handle_in_chat_command(
     session: &mut Session,
-    chat_id: &str,
     content: &str,
 ) -> Result<Option<String>, AgentError> {
     match parse_in_chat_command(content) {
         Some(InChatCommand::FreshConversation) => {
-            session.reset_chat_context(chat_id)?;
+            // Archive the current session
-            Ok(Some("Started a fresh conversation.".to_string()))
+            session.archive()?;
+
+            // Return new dialog_id to be created
+            Ok(Some(short_id()))
         }
         None => Ok(None),
     }
@@ -327,73 +309,246 @@ impl SessionManager {
             .map_err(|err| AgentError::Other(format!("load messages error: {}", err)))
     }
 
-    /// 确保 session 存在且未超时，超时则重建
+    // =========================================================================
-    pub async fn ensure_session(&self, channel_name: &str) -> Result<(), AgentError> {
+    // Dialog management methods (UnifiedSessionId based)
-        let mut inner = self.inner.lock().await;
+    // =========================================================================
 
-        let should_recreate = if let Some(last_active) = inner.session_timestamps.get(channel_name) {
+    /// Create a new session (dialog) and return (session_id, title)
-            let elapsed = last_active.elapsed();
+    pub async fn create_session(
-            if elapsed > inner.session_ttl {
+        &self,
-                tracing::info!(channel = %channel_name, elapsed_hours = elapsed.as_secs() / 3600, "Session expired, recreating");
+        channel: &str,
-                true
+        chat_id: &str,
-            } else {
+        title: Option<&str>,
-                false
+    ) -> Result<(UnifiedSessionId, String), AgentError> {
-            }
+        let dialog_id = short_id();
-        } else {
+        let unified_id = UnifiedSessionId::new(channel, chat_id, &dialog_id);
-            #[cfg(debug_assertions)]
+        let session_id_str = unified_id.to_string();
-            tracing::debug!(channel = %channel_name, "Creating new session");
-            true
-        };
 
-        if should_recreate {
+        let title = title
-            // 移除旧 session
+            .map(str::trim)
-            inner.sessions.remove(channel_name);
+            .filter(|value| !value.is_empty())
+            .map(ToOwned::to_owned)
+            .unwrap_or_else(|| format!("Dialog {}", &dialog_id));
 
-            // 创建新 session（使用临时 user_tx，因为 Feishu 不通过 WS）
+        // Ensure storage record exists
+        self.store
+            .ensure_channel_session(channel, chat_id, &dialog_id)
+            .map_err(|err| AgentError::Other(format!("create session error: {}", err)))?;
+
+        // Create session instance
         let (user_tx, _rx) = mpsc::channel::<WsOutbound>(100);
         let session = Session::new(
-                channel_name.to_string(),
+            unified_id.clone(),
             self.provider_config.clone(),
             user_tx,
             self.tools.clone(),
             self.store.clone(),
         )
         .await?;
+
         let arc = Arc::new(Mutex::new(session));
+        let inner = &mut *self.inner.lock().await;
+        inner.sessions.insert(session_id_str.clone(), arc.clone());
+        inner.session_timestamps.insert(session_id_str, Instant::now());
 
-            inner.sessions.insert(channel_name.to_string(), arc.clone());
+        Ok((unified_id, title))
-            inner.session_timestamps.insert(channel_name.to_string(), Instant::now());
     }
 
-        Ok(())
+    /// Get or create a session by UnifiedSessionId
+    pub async fn get_or_create_session(&self, unified_id: &UnifiedSessionId) -> Result<Arc<Mutex<Session>>, AgentError> {
+        let session_id_str = unified_id.to_string();
+        let inner = &mut *self.inner.lock().await;
+
+        // Check if session exists
+        if let Some(session) = inner.sessions.get(&session_id_str) {
+            // Update timestamp
+            inner.session_timestamps.insert(session_id_str, Instant::now());
+            return Ok(session.clone());
         }
 
-    /// 获取 session（不检查超时）
+        // Check if session exists in storage
-    pub async fn get(&self, channel_name: &str) -> Option<Arc<Mutex<Session>>> {
+        if let Ok(Some(_)) = self.store.get_session(&session_id_str) {
-        let inner = self.inner.lock().await;
+            // Create session instance from storage
-        inner.sessions.get(channel_name).cloned()
+            let (user_tx, _rx) = mpsc::channel::<WsOutbound>(100);
+            let session = Session::new(
+                unified_id.clone(),
+                self.provider_config.clone(),
+                user_tx,
+                self.tools.clone(),
+                self.store.clone(),
+            )
+            .await?;
+
+            let arc = Arc::new(Mutex::new(session));
+            inner.sessions.insert(session_id_str.clone(), arc.clone());
+            inner.session_timestamps.insert(session_id_str, Instant::now());
+            return Ok(arc);
         }
 
-    /// 更新最后活跃时间
+        // Session doesn't exist - create new directly
-    pub async fn touch(&self, channel_name: &str) {
+        let (user_tx, _rx) = mpsc::channel::<WsOutbound>(100);
-        let mut inner = self.inner.lock().await;
+        let session = Session::new(
-        inner.session_timestamps.insert(channel_name.to_string(), Instant::now());
+            unified_id.clone(),
+            self.provider_config.clone(),
+            user_tx,
+            self.tools.clone(),
+            self.store.clone(),
+        )
+        .await?;
+
+        let arc = Arc::new(Mutex::new(session));
+        inner.sessions.insert(session_id_str.clone(), arc.clone());
+        inner.session_timestamps.insert(session_id_str, Instant::now());
+        Ok(arc)
+    }
+
+    /// List all dialogs for a chat scope (internal)
+    async fn list_dialogs_for_chat(
+        &self,
+        channel: &str,
+        chat_id: &str,
+        include_archived: bool,
+    ) -> Result<Vec<DialogInfo>, AgentError> {
+        let records = self.store
+            .list_sessions(channel, include_archived)
+            .map_err(|err| AgentError::Other(format!("list dialogs error: {}", err)))?;
+
+        let dialogs: Vec<DialogInfo> = records
+            .into_iter()
+            .filter(|r| {
+                // Filter to only dialogs for this chat_id
+                if let Some(sid) = UnifiedSessionId::parse(&r.id) {
+                    sid.chat_id == chat_id
+                } else {
+                    false
+                }
+            })
+            .map(|r| {
+                let sid = UnifiedSessionId::parse(&r.id).unwrap();
+                DialogInfo {
+                    session_id: sid,
+                    title: r.title,
+                    created_at: r.created_at,
+                    last_active_at: r.last_active_at,
+                    message_count: r.message_count,
+                    archived_at: r.archived_at,
+                }
+            })
+            .collect();
+
+        Ok(dialogs)
+    }
+
+    /// Get the most recent dialog for a chat scope (from storage)
+    pub async fn get_most_recent_dialog(
+        &self,
+        channel: &str,
+        chat_id: &str,
+    ) -> Result<Option<UnifiedSessionId>, AgentError> {
+        let records = self.store
+            .list_sessions(channel, false)
+            .map_err(|err| AgentError::Other(format!("get recent dialog error: {}", err)))?;
+
+        let most_recent = records
+            .into_iter()
+            .filter(|r| {
+                if let Some(sid) = UnifiedSessionId::parse(&r.id) {
+                    sid.chat_id == chat_id
+                } else {
+                    false
+                }
+            })
+            .max_by_key(|r| r.last_active_at);
+
+        Ok(most_recent.map(|r| UnifiedSessionId::parse(&r.id).unwrap()))
+    }
+
+    /// Rename a dialog
+    pub fn rename_dialog(&self, session_id: &UnifiedSessionId, title: &str) -> Result<(), AgentError> {
+        self.store
+            .rename_session(&session_id.to_string(), title)
+            .map_err(|err| AgentError::Other(format!("rename dialog error: {}", err)))
+    }
+
+    /// Create a new dialog (wrapper for create_session to match gateway interface)
+    pub async fn create_dialog(
+        &self,
+        channel: &str,
+        chat_id: &str,
+        title: Option<&str>,
+    ) -> Result<(UnifiedSessionId, String), AgentError> {
+        self.create_session(channel, chat_id, title).await
+    }
+
+    /// Get current dialog for a chat (wrapper for get_most_recent_dialog)
+    pub async fn get_current_dialog(
+        &self,
+        channel: &str,
+        chat_id: &str,
+    ) -> Result<Option<UnifiedSessionId>, AgentError> {
+        self.get_most_recent_dialog(channel, chat_id).await
+    }
+
+    /// Switch to a different dialog - not applicable in new architecture
+    /// Each Session IS a dialog, so switching is just loading that session
+    pub async fn switch_dialog(
+        &self,
+        _channel: &str,
+        _chat_id: &str,
+        _dialog_id: &str,
+    ) -> Result<UnifiedSessionId, AgentError> {
+        Err(AgentError::Other("switch_dialog not applicable in new architecture".to_string()))
+    }
+
+    /// List all dialogs for a chat scope (returns tuple for gateway compatibility)
+    pub async fn list_dialogs(
+        &self,
+        channel: &str,
+        chat_id: &str,
+        include_archived: bool,
+    ) -> Result<(Vec<DialogInfo>, Option<String>), AgentError> {
+        let dialogs = self.list_dialogs_for_chat(channel, chat_id, include_archived).await?;
+        let current = self.get_most_recent_dialog(channel, chat_id).await?;
+        Ok((dialogs, current.map(|id| id.to_string())))
+    }
+
+    /// Archive a dialog
+    pub fn archive_dialog(&self, session_id: &UnifiedSessionId) -> Result<(), AgentError> {
+        self.store
+            .archive_session(&session_id.to_string())
+            .map_err(|err| AgentError::Other(format!("archive dialog error: {}", err)))
+    }
+
+    /// Delete a dialog
+    pub fn delete_dialog(&self, session_id: &UnifiedSessionId) -> Result<(), AgentError> {
+        self.store
+            .delete_session(&session_id.to_string())
+            .map_err(|err| AgentError::Other(format!("delete dialog error: {}", err)))
+    }
+
+    /// Clear dialog history
+    pub fn clear_dialog_history(&self, session_id: &UnifiedSessionId) -> Result<(), AgentError> {
+        self.store
+            .clear_messages(&session_id.to_string())
+            .map_err(|err| AgentError::Other(format!("clear dialog history error: {}", err)))
     }
 
     /// 处理消息：路由到对应 session 的 agent
     pub async fn handle_message(
         &self,
-        channel_name: &str,
+        channel: &str,
         _sender_id: &str,
         chat_id: &str,
+        dialog_id: Option<&str>,
         content: &str,
         media: Vec<crate::bus::MediaItem>,
     ) -> Result<String, AgentError> {
         #[cfg(debug_assertions)]
         {
             tracing::debug!(
-                channel = %channel_name,
+                channel = %channel,
                 chat_id = %chat_id,
+                dialog_id = ?dialog_id,
                 content_len = content.len(),
                 media_count = %media.len(),
                 "Routing message to agent"
@@ -403,28 +558,41 @@ impl SessionManager {
             }
         }
 
-        // 确保 session 存在（可能需要重建）
+        // 确定 dialog_id
-        self.ensure_session(channel_name).await?;
+        let dialog_id = dialog_id.unwrap_or(DEFAULT_DIALOG_ID);
 
-        // 更新活跃时间
+        // 获取或创建 session
-        self.touch(channel_name).await;
+        let unified_id = UnifiedSessionId::new(channel, chat_id, dialog_id);
-
+        let session = self.get_or_create_session(&unified_id).await?;
-        // 获取 session
-        let session = self
-            .get(channel_name)
-            .await
-            .ok_or_else(|| AgentError::Other("Session not found".to_string()))?;
 
         // 处理消息
-        let response = {
+        let response: String = {
             let mut session_guard = session.lock().await;
 
-            session_guard.ensure_persistent_session(chat_id)?;
+            // 检查是否是 FreshConversation 命令
-            session_guard.ensure_chat_loaded(chat_id)?;
+            let fresh_conversation_result = handle_in_chat_command(&mut session_guard, content)?;
 
-            if let Some(command_response) = handle_in_chat_command(&mut session_guard, chat_id, content)? {
+            let (session_to_use, fresh_started) = match fresh_conversation_result {
-                return Ok(command_response);
+                Some(_new_dialog_id) => {
+                    // Archive the old session
+                    session_guard.archive()?;
+                    drop(session_guard);
+
+                    // Create new session for the new dialog
+                    // This creates and registers the session
+                    let (new_unified_id, _title) = self.create_session(channel, chat_id, None).await?;
+                    // Get the newly created session
+                    let new_session = self.get_or_create_session(&new_unified_id).await?;
+                    (new_session, true)
                 }
+                None => (Arc::clone(&session), false),
+            };
+
+            // 使用选定的 session 进行处理
+            let mut session_guard = session_to_use.lock().await;
+
+            // 确保 session 持久化记录存在
+            session_guard.ensure_persistent_session()?;
 
             // 添加用户消息到历史
             let media_refs: Vec<String> = media.iter().map(|m| m.path.clone()).collect();
@@ -432,13 +600,16 @@ impl SessionManager {
             if !media_refs.is_empty() {
                 tracing::debug!(media_count = %media.len(), media_refs = ?media_refs, "Adding user message with media");
             }
-            let user_message = session_guard.create_user_message(content, media_refs);
-            session_guard.append_persisted_message(chat_id, user_message)?;
 
-            // 获取完整历史
+            let user_message = session_guard.create_user_message(content, media_refs);
-            let history = session_guard.get_or_create_history(chat_id).clone();
+            session_guard.add_message(user_message.clone());
+            session_guard.append_message(&user_message)?;
+
+            // 加载历史
+            session_guard.load_history()?;
 
             // 压缩历史（如果需要）
+            let history = session_guard.get_history().to_vec();
             let history = session_guard.compressor
                 .compress_if_needed(history)
                 .await?;
@@ -447,29 +618,35 @@ impl SessionManager {
             let agent = session_guard.create_agent()?;
             let result = agent.process(history).await?;
 
-            // 按真实顺序持久化 assistant tool_calls、tool 结果和最终 assistant 回复
+            // 持久化 assistant 消息
-            session_guard.append_persisted_messages(chat_id, result.emitted_messages.clone())?;
+            for msg in &result.emitted_messages {
+                session_guard.append_message(msg)?;
+            }
 
-            result.final_response
+            // 如果是 FreshConversation 命令，返回命令消息
+            if fresh_started {
+                "Starting a fresh conversation...".to_string()
+            } else {
+                result.final_response.content
+            }
         };
 
         #[cfg(debug_assertions)]
         tracing::debug!(
-            channel = %channel_name,
+            channel = %channel,
             chat_id = %chat_id,
-            response_len = response.content.len(),
+            response_len = %response.len(),
             "Agent response received"
         );
 
-        Ok(response.content)
+        Ok(response)
     }
 
     /// 清除指定 session 的所有历史
-    pub async fn clear_session_history(&self, channel_name: &str) -> Result<(), AgentError> {
+    pub async fn clear_session_history(&self, unified_id: &UnifiedSessionId) -> Result<(), AgentError> {
-        if let Some(session) = self.get(channel_name).await {
+        let session = self.get_or_create_session(unified_id).await?;
         let mut session_guard = session.lock().await;
-            session_guard.clear_all_history()?;
+        session_guard.clear_history()?;
-        }
         Ok(())
     }
 }
@@ -503,44 +680,4 @@ mod tests {
         assert_eq!(parse_in_chat_command("/new planning"), None);
         assert_eq!(parse_in_chat_command("please /reset"), None);
     }
-
-    #[tokio::test]
-    async fn test_handle_in_chat_command_resets_active_history_only() {
-        let store = Arc::new(SessionStore::in_memory().unwrap());
-        let (user_tx, _user_rx) = mpsc::channel(4);
-        let tools = Arc::new(default_tools());
-        let mut session = Session::new(
-            "feishu".to_string(),
-            test_provider_config(),
-            user_tx,
-            tools,
-            store.clone(),
-        )
-        .await
-        .unwrap();
-
-        session.ensure_persistent_session("chat-1").unwrap();
-        session.ensure_chat_loaded("chat-1").unwrap();
-        session
-            .append_persisted_message("chat-1", ChatMessage::user("hello"))
-            .unwrap();
-
-        let response = handle_in_chat_command(&mut session, "chat-1", "/reset")
-            .unwrap()
-            .unwrap();
-
-        assert_eq!(response, "Started a fresh conversation.");
-        assert!(session.get_history("chat-1").unwrap().is_empty());
-        assert!(store
-            .load_messages(&session.persistent_session_id("chat-1"))
-            .unwrap()
-            .is_empty());
-        assert_eq!(
-            store
-                .load_all_messages(&session.persistent_session_id("chat-1"))
-                .unwrap()
-                .len(),
-            1,
-        );
-    }
 }

src/session/session_id.rs

@@ -0,0 +1,120 @@
+/// Unified session identifier composed of channel, chat_id, and dialog_id
+///
+/// Format: `channel:chat_id:dialog_id`
+///
+/// Examples:
+/// - CLI: `"cli_chat:sid_abc123:dialog_xyz"`
+/// - Feishu: `"feishu:oc_123456:dialog_xyz"`
+///
+/// For simple cases where only one dialog exists per chat:
+/// - `dialog_id` defaults to `"default"`
+
+use serde::{Deserialize, Serialize};
+
+pub const DEFAULT_DIALOG_ID: &str = "default";
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
+pub struct UnifiedSessionId {
+    pub channel: String,
+    pub chat_id: String,
+    pub dialog_id: String,
+}
+
+impl UnifiedSessionId {
+    /// Create a new UnifiedSessionId
+    pub fn new(channel: impl Into<String>, chat_id: impl Into<String>, dialog_id: impl Into<String>) -> Self {
+        Self {
+            channel: channel.into(),
+            chat_id: chat_id.into(),
+            dialog_id: dialog_id.into(),
+        }
+    }
+
+    /// Create with default dialog_id ("default")
+    pub fn with_default_dialog(channel: impl Into<String>, chat_id: impl Into<String>) -> Self {
+        Self {
+            channel: channel.into(),
+            chat_id: chat_id.into(),
+            dialog_id: DEFAULT_DIALOG_ID.to_string(),
+        }
+    }
+
+    /// Parse from string format "channel:chat_id:dialog_id"
+    pub fn parse(s: &str) -> Option<Self> {
+        let parts: Vec<&str> = s.split(':').collect();
+        if parts.len() != 3 {
+            return None;
+        }
+        Some(Self {
+            channel: parts[0].to_string(),
+            chat_id: parts[1].to_string(),
+            dialog_id: parts[2].to_string(),
+        })
+    }
+
+    /// Convert to string format "channel:chat_id:dialog_id"
+    pub fn to_string(&self) -> String {
+        format!("{}:{}:{}", self.channel, self.chat_id, self.dialog_id)
+    }
+
+    /// Get the session key without dialog_id (channel:chat_id)
+    /// This is used to group all dialogs within a chat
+    pub fn chat_scope(&self) -> String {
+        format!("{}:{}", self.channel, self.chat_id)
+    }
+}
+
+impl std::fmt::Display for UnifiedSessionId {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.to_string())
+    }
+}
+
+// Note: No Deref implementation to avoid confusion between String and UnifiedSessionId
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_new() {
+        let id = UnifiedSessionId::new("cli_chat", "sid123", "dialog456");
+        assert_eq!(id.channel, "cli_chat");
+        assert_eq!(id.chat_id, "sid123");
+        assert_eq!(id.dialog_id, "dialog456");
+    }
+
+    #[test]
+    fn test_with_default_dialog() {
+        let id = UnifiedSessionId::with_default_dialog("feishu", "oc123");
+        assert_eq!(id.channel, "feishu");
+        assert_eq!(id.chat_id, "oc123");
+        assert_eq!(id.dialog_id, "default");
+    }
+
+    #[test]
+    fn test_parse() {
+        let id = UnifiedSessionId::parse("cli_chat:sid123:dialog456").unwrap();
+        assert_eq!(id.channel, "cli_chat");
+        assert_eq!(id.chat_id, "sid123");
+        assert_eq!(id.dialog_id, "dialog456");
+    }
+
+    #[test]
+    fn test_parse_invalid() {
+        assert!(UnifiedSessionId::parse("invalid").is_none());
+        assert!(UnifiedSessionId::parse("only:two").is_none());
+    }
+
+    #[test]
+    fn test_to_string() {
+        let id = UnifiedSessionId::new("feishu", "oc123", "dialog789");
+        assert_eq!(id.to_string(), "feishu:oc123:dialog789");
+    }
+
+    #[test]
+    fn test_chat_scope() {
+        let id = UnifiedSessionId::new("feishu", "oc123", "dialog789");
+        assert_eq!(id.chat_scope(), "feishu:oc123");
+    }
+}

src/storage/mod.rs

@@ -140,8 +140,9 @@ impl SessionStore {
         &self,
         channel_name: &str,
         chat_id: &str,
+        dialog_id: &str,
     ) -> Result<SessionRecord, StorageError> {
-        let session_id = persistent_session_id(channel_name, chat_id);
+        let session_id = persistent_session_id(channel_name, chat_id, dialog_id);
         if let Some(record) = self.get_session(&session_id)? {
             return Ok(record);
         }
@@ -343,12 +344,8 @@ impl SessionStore {
     }
 }
 
-pub fn persistent_session_id(channel_name: &str, chat_id: &str) -> String {
+pub fn persistent_session_id(channel_name: &str, chat_id: &str, dialog_id: &str) -> String {
-    if channel_name == "cli" || channel_name == "cli_chat" {
+    format!("{}:{}:{}", channel_name, chat_id, dialog_id)
-        chat_id.to_string()
-    } else {
-        format!("{}:{}", channel_name, chat_id)
-    }
 }
 
 fn default_session_db_path() -> Result<PathBuf, std::io::Error> {
@@ -474,9 +471,9 @@ mod tests {
 
     #[test]
     fn test_persistent_session_id_for_cli_and_channel() {
-        assert_eq!(persistent_session_id("cli", "abc"), "abc");
+        assert_eq!(persistent_session_id("cli", "abc", "default"), "cli:abc:default");
-        assert_eq!(persistent_session_id("cli_chat", "abc"), "abc");
+        assert_eq!(persistent_session_id("cli_chat", "abc", "default"), "cli_chat:abc:default");
-        assert_eq!(persistent_session_id("feishu", "abc"), "feishu:abc");
+        assert_eq!(persistent_session_id("feishu", "abc", "default"), "feishu:abc:default");
     }
 
     #[test]
@@ -535,8 +532,8 @@ mod tests {
     fn test_ensure_channel_session_is_stable() {
         let store = SessionStore::in_memory().unwrap();
 
-        let first = store.ensure_channel_session("feishu", "chat-1").unwrap();
+        let first = store.ensure_channel_session("feishu", "chat-1", "default").unwrap();
-        let second = store.ensure_channel_session("feishu", "chat-1").unwrap();
+        let second = store.ensure_channel_session("feishu", "chat-1", "default").unwrap();
 
         assert_eq!(first.id, second.id);
         assert_eq!(first.chat_id, "chat-1");