kefu_cloud/server/internal/handler/session.go

package handler

import (
	"net/http"
	"strconv"
	"strings"
	"time"
	"unicode/utf8"

	"github.com/gin-gonic/gin"
	"gorm.io/gorm"
	"kefu-cloud/server/internal/middleware"
	"kefu-cloud/server/internal/model"
	"kefu-cloud/server/internal/ws"
)

type SessionHandler struct{}

func NewSessionHandler() *SessionHandler { return &SessionHandler{} }

type SendMessageReq struct {
	Content string `json:"content" binding:"required"`
	Type    string `json:"type"`
}

type SessionListItem struct {
	model.Session
	UnreadCount   int        `json:"unread_count"`
	LastMessage   string     `json:"last_message"`
	LastMessageAt *time.Time `json:"last_message_at,omitempty"`
	MessageCount  int        `json:"message_count"`
	CustomerName  string     `json:"customer_name"`
	AgentName     string     `json:"agent_name"`
	ChannelName   string     `json:"channel_name"`
	ChannelType   string     `json:"channel_type"`
}

type CreateNoteReq struct {
	Content string `json:"content" binding:"required"`
}

func (h *SessionHandler) SendMessage(c *gin.Context) {
	userID := middleware.GetUserID(c)
	id := c.Param("id")

	var req SendMessageReq
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "参数错误"})
		return
	}
	if req.Type == "" {
		req.Type = "text"
	}
	content, err := validateMessageContent(req.Type, req.Content)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": err.Error()})
		return
	}

	session, ok := loadTenantSession(c, id)
	if !ok {
		return
	}
	if !canOperateSession(c, session) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "无权向该会话发送消息"})
		return
	}
	if session.Status == "ended" || session.Status == "archived" {
		c.JSON(http.StatusConflict, gin.H{"code": 409, "message": "会话已结束"})
		return
	}

	msg := model.Message{
		SessionID:  session.ID,
		SenderType: "agent",
		SenderID:   &userID,
		Content:    content,
		Type:       req.Type,
		SentAt:     time.Now(),
	}

	if err := model.CreateMessage(&msg); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "发送失败"})
		return
	}
	if middleware.GetRole(c) == "agent" {
		model.DB.Model(&model.Session{}).Where("id = ?", session.ID).Update("last_read_seq", msg.Seq)
		session.LastReadSeq = msg.Seq
	}
	broadcastSessionMessage(session, msg)

	middleware.JSON(c, msg)
}

type CreateSessionReq struct {
	ChannelID  uint   `json:"channel_id"`
	CustomerID uint   `json:"customer_id"`
	Priority   string `json:"priority"`
}

type AssignSessionReq struct {
	AgentID uint `json:"agent_id"`
}

func isTenantManager(c *gin.Context) bool {
	return middleware.HasAnyRole(c, "admin", "supervisor")
}

func loadTenantSession(c *gin.Context, id string) (*model.Session, bool) {
	var session model.Session
	if err := model.DB.First(&session, id).Error; err != nil {
		c.JSON(http.StatusNotFound, gin.H{"code": 404, "message": "会话不存在"})
		return nil, false
	}
	if session.TenantID != middleware.GetTenantID(c) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "无权访问其他租户会话"})
		return nil, false
	}
	return &session, true
}

func canReadSession(c *gin.Context, session *model.Session) bool {
	if isTenantManager(c) {
		return true
	}
	if middleware.GetRole(c) == "agent" {
		userID := middleware.GetUserID(c)
		return session.Status == "waiting" || (session.AgentID != nil && *session.AgentID == userID)
	}
	return false
}

func canOperateSession(c *gin.Context, session *model.Session) bool {
	if isTenantManager(c) {
		return true
	}
	return middleware.GetRole(c) == "agent" && session.AgentID != nil && *session.AgentID == middleware.GetUserID(c)
}

func broadcastSessionMessage(session *model.Session, message model.Message) {
	payload, err := ws.NewEvent("message", session.ID, message)
	if err == nil {
		ws.DefaultHub.BroadcastToSession(session.TenantID, session.ID, session.AgentID, payload)
	}
}

func broadcastSessionUpdate(session *model.Session) {
	payload, err := ws.NewEvent("session_updated", session.ID, gin.H{"status": session.Status})
	if err != nil {
		return
	}
	// 坐席列表需要刷新；访客也必须收到 ended/active，才能弹出评价或更新接待状态
	ws.DefaultHub.BroadcastToTenantStaff(session.TenantID, payload)
	ws.DefaultHub.BroadcastToVisitor(session.TenantID, session.ID, payload)
}

func loadAssignableAgent(tenantID, agentID uint) error {
	var agent model.User
	if err := model.DB.First(&agent, agentID).Error; err != nil {
		return err
	}
	if agent.TenantID != tenantID || agent.Role != "agent" || agent.Status == "disabled" {
		return gorm.ErrRecordNotFound
	}
	return nil
}

func unreadCount(session model.Session) int {
	var count int64
	model.DB.Model(&model.Message{}).
		Where("session_id = ? AND sender_type = ? AND seq > ?", session.ID, "visitor", session.LastReadSeq).
		Count(&count)
	return int(count)
}

func (h *SessionHandler) List(c *gin.Context) {
	tenantID := middleware.GetTenantID(c)
	page, pageSize := middleware.GetPageParams(c)
	status := c.Query("status")
	priority := c.Query("priority")
	agentID := c.Query("agent_id")
	channelID := c.Query("channel_id")
	search := strings.TrimSpace(c.Query("search"))
	from := c.Query("from")
	to := c.Query("to")

	var sessions []model.Session
	var total int64

	query := model.DB.Model(&model.Session{}).Where("sessions.tenant_id = ?", tenantID)
	if middleware.GetRole(c) == "agent" {
		query = query.Where("sessions.agent_id = ? OR sessions.status = ?", middleware.GetUserID(c), "waiting")
	}
	if status != "" {
		query = query.Where("sessions.status = ?", status)
	}
	if priority != "" {
		query = query.Where("sessions.priority = ?", priority)
	}
	if agentID != "" {
		query = query.Where("sessions.agent_id = ?", agentID)
	}
	if channelID != "" {
		query = query.Where("sessions.channel_id = ?", channelID)
	}
	if from != "" {
		if t, err := time.ParseInLocation("2006-01-02", from, time.Local); err == nil {
			query = query.Where("sessions.created_at >= ?", t)
		}
	}
	if to != "" {
		if t, err := time.ParseInLocation("2006-01-02", to, time.Local); err == nil {
			query = query.Where("sessions.created_at < ?", t.Add(24*time.Hour))
		}
	}
	if search != "" {
		like := "%" + search + "%"
		query = query.Joins("LEFT JOIN customers ON customers.id = sessions.customer_id").
			Where("customers.name LIKE ? OR CAST(sessions.id AS TEXT) LIKE ? OR COALESCE(sessions.end_reason, '') LIKE ?", like, like, like)
	}

	query.Count(&total)
	if err := query.Order("sessions.created_at desc").Offset((page - 1) * pageSize).Limit(pageSize).Find(&sessions).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "查询会话失败"})
		return
	}

	// 批量补全客户 / 客服 / 渠道 / 消息数
	customerIDs := make([]uint, 0)
	agentIDs := make([]uint, 0)
	channelIDs := make([]uint, 0)
	sessionIDs := make([]uint, 0, len(sessions))
	for _, s := range sessions {
		sessionIDs = append(sessionIDs, s.ID)
		customerIDs = append(customerIDs, s.CustomerID)
		channelIDs = append(channelIDs, s.ChannelID)
		if s.AgentID != nil {
			agentIDs = append(agentIDs, *s.AgentID)
		}
	}
	customerMap := map[uint]model.Customer{}
	if len(customerIDs) > 0 {
		var customers []model.Customer
		model.DB.Where("id IN ?", uniqueUint(customerIDs)).Find(&customers)
		for _, cu := range customers {
			customerMap[cu.ID] = cu
		}
	}
	agentMap := map[uint]model.User{}
	if len(agentIDs) > 0 {
		var users []model.User
		model.DB.Where("id IN ?", uniqueUint(agentIDs)).Find(&users)
		for _, u := range users {
			agentMap[u.ID] = u
		}
	}
	channelMap := map[uint]model.Channel{}
	if len(channelIDs) > 0 {
		var channels []model.Channel
		model.DB.Where("id IN ?", uniqueUint(channelIDs)).Find(&channels)
		for _, ch := range channels {
			channelMap[ch.ID] = ch
		}
	}
	msgCountMap := map[uint]int{}
	if len(sessionIDs) > 0 {
		type row struct {
			SessionID uint
			Cnt       int
		}
		var rows []row
		model.DB.Model(&model.Message{}).
			Select("session_id, COUNT(*) as cnt").
			Where("session_id IN ?", sessionIDs).
			Group("session_id").
			Scan(&rows)
		for _, r := range rows {
			msgCountMap[r.SessionID] = r.Cnt
		}
	}

	items := make([]SessionListItem, 0, len(sessions))
	for _, session := range sessions {
		item := SessionListItem{Session: session, MessageCount: msgCountMap[session.ID]}
		if middleware.GetRole(c) == "agent" && session.AgentID != nil && *session.AgentID == middleware.GetUserID(c) {
			item.UnreadCount = unreadCount(session)
		}
		if cu, ok := customerMap[session.CustomerID]; ok {
			item.CustomerName = cu.Name
		}
		if session.AgentID != nil {
			if u, ok := agentMap[*session.AgentID]; ok {
				item.AgentName = u.Nickname
			}
		}
		if ch, ok := channelMap[session.ChannelID]; ok {
			item.ChannelName = ch.Name
			item.ChannelType = ch.Type
		}
		var lastMsg model.Message
		if err := model.DB.Where("session_id = ?", session.ID).Order("seq desc").First(&lastMsg).Error; err == nil {
			if lastMsg.Type == "image" {
				item.LastMessage = "[图片]"
			} else {
				item.LastMessage = lastMsg.Content
				if utf8.RuneCountInString(item.LastMessage) > 40 {
					runes := []rune(item.LastMessage)
					item.LastMessage = string(runes[:40]) + "…"
				}
			}
			t := lastMsg.SentAt
			item.LastMessageAt = &t
		}
		items = append(items, item)
	}

	middleware.JSONList(c, items, total, page, pageSize)
}

func uniqueUint(ids []uint) []uint {
	seen := make(map[uint]struct{}, len(ids))
	out := make([]uint, 0, len(ids))
	for _, id := range ids {
		if id == 0 {
			continue
		}
		if _, ok := seen[id]; ok {
			continue
		}
		seen[id] = struct{}{}
		out = append(out, id)
	}
	return out
}

func (h *SessionHandler) Get(c *gin.Context) {
	id := c.Param("id")

	session, ok := loadTenantSession(c, id)
	if !ok {
		return
	}
	if !canReadSession(c, session) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "无权查看该会话"})
		return
	}

	var messages []model.Message
	if err := model.DB.Where("session_id = ?", session.ID).Order("seq asc").Find(&messages).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "查询消息失败"})
		return
	}
	var events []model.SessionEvent
	model.DB.Where("session_id = ?", session.ID).Order("created_at asc").Find(&events)
	var pageViews []model.VisitorPageView
	model.DB.Where("session_id = ?", session.ID).Order("entered_at asc").Limit(maxPageViewsPerSession).Find(&pageViews)
	var pendingCount int64
	model.DB.Model(&model.Session{}).Where("customer_id = ? AND tenant_id = ? AND status = ?", session.CustomerID, session.TenantID, "waiting").Count(&pendingCount)

	maxSeq := 0
	for _, m := range messages {
		if m.Seq > maxSeq {
			maxSeq = m.Seq
		}
	}
	middleware.JSON(c, gin.H{
		"session":       session,
		"messages":      messages,
		"events":        events,
		"page_views":    pageViews,
		"pending_count": pendingCount,
		"max_seq":       maxSeq,
	})
}

// ListMessages 按 seq 增量拉取消息：after_seq 之后的新消息（重连 catch-up）。
// GET /sessions/:id/messages?after_seq=12
func (h *SessionHandler) ListMessages(c *gin.Context) {
	session, ok := loadTenantSession(c, c.Param("id"))
	if !ok {
		return
	}
	if !canReadSession(c, session) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "无权查看该会话消息"})
		return
	}

	afterSeq := 0
	if raw := strings.TrimSpace(c.Query("after_seq")); raw != "" {
		parsed, err := strconv.Atoi(raw)
		if err != nil || parsed < 0 {
			c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "after_seq 无效"})
			return
		}
		afterSeq = parsed
	}

	limit := 200
	if raw := strings.TrimSpace(c.Query("limit")); raw != "" {
		if parsed, err := strconv.Atoi(raw); err == nil && parsed > 0 {
			if parsed > 500 {
				parsed = 500
			}
			limit = parsed
		}
	}

	query := model.DB.Where("session_id = ?", session.ID)
	if afterSeq > 0 {
		query = query.Where("seq > ?", afterSeq)
	}

	var messages []model.Message
	if err := query.Order("seq asc").Limit(limit).Find(&messages).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "查询消息失败"})
		return
	}

	var maxSeq int
	if err := model.DB.Model(&model.Message{}).
		Where("session_id = ?", session.ID).
		Select("COALESCE(MAX(seq), 0)").
		Scan(&maxSeq).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "查询消息失败"})
		return
	}

	middleware.JSON(c, gin.H{
		"messages":  messages,
		"after_seq": afterSeq,
		"max_seq":   maxSeq,
		"has_more":  len(messages) >= limit && (len(messages) == 0 || messages[len(messages)-1].Seq < maxSeq),
	})
}

func (h *SessionHandler) MarkRead(c *gin.Context) {
	session, ok := loadTenantSession(c, c.Param("id"))
	if !ok {
		return
	}
	if !canReadSession(c, session) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "无权标记该会话已读"})
		return
	}
	if session.AgentID == nil || middleware.GetRole(c) != "agent" || *session.AgentID != middleware.GetUserID(c) {
		middleware.JSON(c, gin.H{"last_read_seq": session.LastReadSeq})
		return
	}
	var maxSeq int
	if err := model.DB.Model(&model.Message{}).Where("session_id = ?", session.ID).Select("COALESCE(MAX(seq), 0)").Scan(&maxSeq).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "标记已读失败"})
		return
	}
	if err := model.DB.Model(&model.Session{}).Where("id = ?", session.ID).Update("last_read_seq", maxSeq).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "标记已读失败"})
		return
	}
	middleware.JSON(c, gin.H{"last_read_seq": maxSeq})
}

func (h *SessionHandler) AddNote(c *gin.Context) {
	session, ok := loadTenantSession(c, c.Param("id"))
	if !ok {
		return
	}
	if !canOperateSession(c, session) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "无权添加内部备注"})
		return
	}
	var req CreateNoteReq
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "参数错误"})
		return
	}
	content := strings.TrimSpace(req.Content)
	if content == "" || utf8.RuneCountInString(content) > 500 {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "内部备注需为 1 至 500 字"})
		return
	}
	event := model.SessionEvent{SessionID: session.ID, OperatorID: middleware.GetUserID(c), Action: "note", Detail: content}
	if err := model.DB.Create(&event).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "保存内部备注失败"})
		return
	}
	middleware.JSON(c, event)
}

func (h *SessionHandler) ListAvailableAgents(c *gin.Context) {
	type agentItem struct {
		ID       uint   `json:"id"`
		Nickname string `json:"nickname"`
		Status   string `json:"status"`
	}
	// all=1 返回租户全部坐席（含离线），用于对话记录筛选；默认仅在线（工作台转接）
	q := model.DB.Where("tenant_id = ? AND role IN ?", middleware.GetTenantID(c), []string{"agent", "supervisor", "admin"})
	if c.Query("all") != "1" {
		q = q.Where("role = ? AND status = ?", "agent", "online")
	}
	var users []model.User
	if err := q.Order("nickname asc").Find(&users).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "查询客服失败"})
		return
	}
	items := make([]agentItem, 0, len(users))
	for _, user := range users {
		items = append(items, agentItem{ID: user.ID, Nickname: user.Nickname, Status: user.Status})
	}
	middleware.JSON(c, items)
}

func (h *SessionHandler) Create(c *gin.Context) {
	if !isTenantManager(c) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "仅主管或管理员可创建会话"})
		return
	}
	var req CreateSessionReq
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "参数错误"})
		return
	}

	tenantID := middleware.GetTenantID(c)
	var channel model.Channel
	if err := model.DB.Where("id = ? AND tenant_id = ? AND status = ?", req.ChannelID, tenantID, "enabled").First(&channel).Error; err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "渠道不存在或未启用"})
		return
	}
	var customer model.Customer
	if err := model.DB.Where("id = ? AND tenant_id = ?", req.CustomerID, tenantID).First(&customer).Error; err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "客户不存在"})
		return
	}

	session := model.Session{
		TenantID:   tenantID,
		ChannelID:  req.ChannelID,
		CustomerID: req.CustomerID,
		Priority:   req.Priority,
		Status:     "waiting",
	}

	if session.Priority == "" {
		session.Priority = "normal"
	}

	if err := model.DB.Create(&session).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "创建会话失败"})
		return
	}
	model.DB.Model(&model.Customer{}).Where("id = ? AND tenant_id = ?", customer.ID, tenantID).
		Updates(map[string]interface{}{"conversation_count": gorm.Expr("conversation_count + 1"), "last_contact_at": time.Now()})

	middleware.JSON(c, session)
}

func (h *SessionHandler) Assign(c *gin.Context) {
	id := c.Param("id")
	session, ok := loadTenantSession(c, id)
	if !ok {
		return
	}
	var req AssignSessionReq
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "参数错误"})
		return
	}

	if session.Status != "waiting" {
		c.JSON(http.StatusConflict, gin.H{"code": 409, "message": "会话已被分配"})
		return
	}
	if middleware.GetRole(c) == "agent" {
		req.AgentID = middleware.GetUserID(c)
	} else if !isTenantManager(c) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "无权分配会话"})
		return
	}
	if req.AgentID == 0 {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "请选择目标客服"})
		return
	}
	if err := loadAssignableAgent(session.TenantID, req.AgentID); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "目标客服不存在或不可用"})
		return
	}

	result := model.DB.Model(&model.Session{}).
		Where("id = ? AND tenant_id = ? AND status = ?", session.ID, session.TenantID, "waiting").
		Updates(map[string]interface{}{"agent_id": req.AgentID, "status": "active", "last_read_seq": 0})

	if result.Error != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "分配失败"})
		return
	}
	if result.RowsAffected == 0 {
		c.JSON(http.StatusConflict, gin.H{"code": 409, "message": "会话已被分配"})
		return
	}

	operatorID := middleware.GetUserID(c)
	operatorName := userDisplayName(operatorID)
	targetName := userDisplayName(req.AgentID)
	detail := "会话分配给 " + targetName
	if operatorID == req.AgentID {
		detail = operatorName + " 领取了会话"
	} else {
		detail = operatorName + " 将会话分配给 " + targetName
	}
	model.DB.Create(&model.SessionEvent{
		SessionID:  session.ID,
		OperatorID: operatorID,
		Action:     "assign",
		Detail:     detail,
	})
	session.AgentID = &req.AgentID
	session.Status = "active"
	broadcastSessionUpdate(session)
	middleware.JSON(c, gin.H{"message": "分配成功", "detail": detail})
}

func userDisplayName(userID uint) string {
	var user model.User
	if err := model.DB.Select("id", "nickname", "username").First(&user, userID).Error; err != nil {
		return "未知坐席"
	}
	if strings.TrimSpace(user.Nickname) != "" {
		return user.Nickname
	}
	if strings.TrimSpace(user.Username) != "" {
		return user.Username
	}
	return "未知坐席"
}

func (h *SessionHandler) Transfer(c *gin.Context) {
	id := c.Param("id")
	session, ok := loadTenantSession(c, id)
	if !ok {
		return
	}
	if !canOperateSession(c, session) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "无权转接该会话"})
		return
	}
	var req AssignSessionReq
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "参数错误"})
		return
	}

	if err := loadAssignableAgent(session.TenantID, req.AgentID); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "目标客服不存在或不可用"})
		return
	}
	if session.AgentID != nil && *session.AgentID == req.AgentID {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "不能转接给当前接待坐席"})
		return
	}

	operatorID := middleware.GetUserID(c)
	operatorName := userDisplayName(operatorID)
	targetName := userDisplayName(req.AgentID)
	fromName := ""
	if session.AgentID != nil {
		fromName = userDisplayName(*session.AgentID)
	}

	result := model.DB.Model(&model.Session{}).
		Where("id = ? AND tenant_id = ? AND status = ?", session.ID, session.TenantID, "active").
		Updates(map[string]interface{}{"agent_id": req.AgentID, "last_read_seq": 0})
	if result.Error != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "转接失败"})
		return
	}
	if result.RowsAffected == 0 {
		c.JSON(http.StatusConflict, gin.H{"code": 409, "message": "会话不可转接"})
		return
	}

	// 详情写明「谁 → 谁」，便于接手坐席在备注/时间线中一眼看清
	detail := operatorName + " 转接给 " + targetName
	if fromName != "" && fromName != operatorName {
		detail = operatorName + " 将会话由 " + fromName + " 转接给 " + targetName
	}

	model.DB.Create(&model.SessionEvent{
		SessionID:  session.ID,
		OperatorID: operatorID,
		Action:     "transfer",
		Detail:     detail,
	})
	session.AgentID = &req.AgentID
	broadcastSessionUpdate(session)

	middleware.JSON(c, gin.H{"message": "转接成功", "detail": detail})
}

func (h *SessionHandler) End(c *gin.Context) {
	id := c.Param("id")
	reason := c.Query("reason")
	session, ok := loadTenantSession(c, id)
	if !ok {
		return
	}
	if !canOperateSession(c, session) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "无权结束该会话"})
		return
	}
	if reason == "" {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "请填写结束原因"})
		return
	}
	if reason != "resolved" && reason != "no_response" && reason != "visitor_left" && reason != "transferred" && reason != "other" {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "结束原因无效"})
		return
	}
	now := time.Now()

	result := model.DB.Model(&model.Session{}).
		Where("id = ? AND tenant_id = ? AND status <> ?", session.ID, session.TenantID, "ended").
		Updates(map[string]interface{}{"status": "ended", "end_reason": reason, "ended_at": now})

	if result.RowsAffected == 0 {
		c.JSON(http.StatusNotFound, gin.H{"code": 404, "message": "会话不存在"})
		return
	}

	model.DB.Create(&model.SessionEvent{
		SessionID:  session.ID,
		OperatorID: middleware.GetUserID(c),
		Action:     "end",
		Detail:     "结束会话: " + reason,
	})
	session.Status = "ended"
	session.EndedAt = &now
	broadcastSessionUpdate(session)

	middleware.JSON(c, gin.H{"message": "已结束"})
}

func (h *SessionHandler) UpdatePriority(c *gin.Context) {
	id := c.Param("id")
	priority := c.Query("priority")
	session, ok := loadTenantSession(c, id)
	if !ok {
		return
	}
	if !canOperateSession(c, session) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "无权更新该会话"})
		return
	}
	if priority != "urgent" && priority != "normal" {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "优先级无效"})
		return
	}

	result := model.DB.Model(&model.Session{}).
		Where("id = ? AND tenant_id = ?", session.ID, session.TenantID).
		Update("priority", priority)
	if result.Error != nil || result.RowsAffected == 0 {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "更新失败"})
		return
	}
	session.Priority = priority
	broadcastSessionUpdate(session)

	middleware.JSON(c, gin.H{"message": "已更新"})
}

// Archive 将已结束会话归档（主管/管理员）
func (h *SessionHandler) Archive(c *gin.Context) {
	if !isTenantManager(c) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "仅主管或管理员可归档"})
		return
	}
	session, ok := loadTenantSession(c, c.Param("id"))
	if !ok {
		return
	}
	if session.Status != "ended" {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "仅已结束的会话可归档"})
		return
	}
	result := model.DB.Model(&model.Session{}).
		Where("id = ? AND tenant_id = ? AND status = ?", session.ID, session.TenantID, "ended").
		Update("status", "archived")
	if result.Error != nil || result.RowsAffected == 0 {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "归档失败"})
		return
	}
	model.DB.Create(&model.SessionEvent{
		SessionID:  session.ID,
		OperatorID: middleware.GetUserID(c),
		Action:     "archive",
		Detail:     "会话已归档",
	})
	session.Status = "archived"
	broadcastSessionUpdate(session)
	middleware.JSON(c, gin.H{"message": "已归档", "session": session})
}

// BatchArchive 批量归档已结束会话
func (h *SessionHandler) BatchArchive(c *gin.Context) {
	if !isTenantManager(c) {
		c.JSON(http.StatusForbidden, gin.H{"code": 403, "message": "仅主管或管理员可归档"})
		return
	}
	var req struct {
		IDs []uint `json:"ids" binding:"required"`
	}
	if err := c.ShouldBindJSON(&req); err != nil || len(req.IDs) == 0 {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "请选择要归档的会话"})
		return
	}
	if len(req.IDs) > 100 {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "单次最多归档 100 条"})
		return
	}
	tenantID := middleware.GetTenantID(c)
	result := model.DB.Model(&model.Session{}).
		Where("tenant_id = ? AND status = ? AND id IN ?", tenantID, "ended", req.IDs).
		Update("status", "archived")
	if result.Error != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"code": 500, "message": "批量归档失败"})
		return
	}
	for _, id := range req.IDs {
		model.DB.Create(&model.SessionEvent{
			SessionID:  id,
			OperatorID: middleware.GetUserID(c),
			Action:     "archive",
			Detail:     "会话已归档",
		})
	}
	middleware.JSON(c, gin.H{"message": "已归档", "count": result.RowsAffected})
}