package services

import (
	"agent-desk/internal/models"
	"agent-desk/internal/pkg/constants"
	"agent-desk/internal/pkg/enums"
	"agent-desk/internal/repositories"
	"github.com/mlogclub/simple/sqls"
	"log/slog"
	"slices"
	"time"
)

const agentPresenceLeaseTTL = 90 * time.Second
const agentPresenceDisconnectGrace = 15 * time.Second
const agentPresenceRenewInterval = 15 * time.Second

func (s *wsService) renewAgentPresence(session *ClientSession) {
	if session == nil || session.Closed.Load() || session.Principal == nil || (session.Role != realtimeRoleAdmin && session.Role != realtimeRoleNotification) {
		return
	}
	session.presenceMu.Lock()
	dispatchPending := false
	defer func() {
		session.presenceMu.Unlock()
		// Finish the presence write before dispatching, and keep ownership in
		// this call rather than launching an untracked database goroutine.
		if dispatchPending {
			_, _ = ConversationDispatchService.DispatchPendingConversations(0)
		}
	}()
	if session.PresenceEnded {
		return
	}
	principal := session.Principal
	if principal.UserType != enums.UserTypeEmployee || !slices.Contains(principal.Permissions, constants.PermissionConversationView.Code) {
		return
	}
	now := time.Now()
	last := session.PresenceRenewedAt.Load()
	if now.Unix()-last < int64(agentPresenceRenewInterval/time.Second) {
		return
	}
	if !session.PresenceRenewedAt.CompareAndSwap(last, now.Unix()) {
		return
	}
	// The internal ID is generated independently per connection, across processes.
	expires := now.Add(agentPresenceLeaseTTL)
	if principal.ExpiresAt.Before(expires) {
		expires = principal.ExpiresAt
	}
	lease := models.AgentPresenceLease{ID: session.PresenceLeaseID, UserID: principal.UserID, LoginSessionID: principal.LoginSessionID, ExpiresAt: expires}
	if lease.ID == "" {
		return
	}
	if err := repositories.SupportAvailabilityRepository.RenewPresence(sqls.DB(), &lease); err != nil {
		slog.Warn("support presence renewal failed")
		return
	}
	if last == 0 {
		dispatchPending = true
	}
}
func (s *wsService) endAgentPresence(session *ClientSession) {
	if session == nil {
		return
	}
	session.presenceMu.Lock()
	defer session.presenceMu.Unlock()
	session.PresenceEnded = true
	if session.PresenceLeaseID == "" || session.PresenceRenewedAt.Load() == 0 {
		return
	}
	if err := repositories.SupportAvailabilityRepository.EndPresence(sqls.DB(), session.PresenceLeaseID, time.Now().Add(agentPresenceDisconnectGrace)); err != nil {
		slog.Warn("support presence disconnect update failed")
	}
}