package main

import (
	"encoding/json"
	"strings"
	"time"

	"github.com/tinode/chat/server/logs"
	"github.com/tinode/chat/server/store/types"
)

const p2pPermissionsRefreshedEvent = "p2p.permissions.refreshed"

type p2pPermissionsPayload struct {
	UserIDs []string `json:"user_ids"`
}

// publishIMP2PPermissionsRefresh asks the topic master to reload permissions
// after the HTTP API has repaired or created the two P2P subscriptions.
func publishIMP2PPermissionsRefresh(tenantID types.TenantID, topic string, uids ...types.Uid) {
	topic = strings.TrimSpace(topic)
	if !tenantID.IsValid() || topic == "" {
		return
	}
	payload := p2pPermissionsPayload{UserIDs: make([]string, 0, len(uids))}
	for _, uid := range uids {
		if !uid.IsZero() {
			payload.UserIDs = append(payload.UserIDs, uid.UserId())
		}
	}
	if len(payload.UserIDs) == 0 {
		return
	}
	encoded, err := json.Marshal(payload)
	if err != nil {
		logs.Warn.Printf("p2p permissions refresh: encode topic=%s: %v", topic, err)
		return
	}
	message := &ServerComMessage{
		TenantID:  tenantID,
		RcptTo:    topic,
		Timestamp: time.Now().UTC().Round(time.Millisecond),
		Info: &MsgServerInfo{
			Topic: topic, What: "p2p", Event: p2pPermissionsRefreshedEvent,
			Payload: json.RawMessage(encoded),
		},
	}
	if globals.hub != nil {
		select {
		case globals.hub.routeSrv <- message:
		default:
			logs.Warn.Printf("p2p permissions refresh: hub queue full topic=%s", topic)
		}
	}
	publishRealtimeTopicMessage(topic, message)
}