新增机器人功能

bot_service.go

@@ -0,0 +1,196 @@
+package main
+
+import (
+	"context"
+	"crypto/rand"
+	"encoding/binary"
+	"fmt"
+	"strings"
+	"time"
+	"unicode/utf8"
+
+	"meshtastic_mqtt_server/mqtpp"
+
+	mqtt "github.com/mochi-mqtt/server/v2"
+)
+
+const botMaxTextBytes = 200
+
+type botSendTextRequest struct {
+	BotID       uint64
+	MessageType string
+	ChannelID   string
+	ToNodeID    string
+	ToNodeNum   *int64
+	Text        string
+	CreatedBy   string
+}
+
+type botTextSender interface {
+	SendText(ctx context.Context, req botSendTextRequest) (*botMessageRecord, error)
+}
+
+type botService struct {
+	store  *store
+	server *mqtt.Server
+	key    []byte
+}
+
+func newBotService(store *store, server *mqtt.Server, key []byte) *botService {
+	return &botService{store: store, server: server, key: key}
+}
+
+func (s *botService) SendText(_ context.Context, req botSendTextRequest) (*botMessageRecord, error) {
+	if s == nil || s.store == nil {
+		return nil, fmt.Errorf("bot service is not configured")
+	}
+	bot, err := s.store.GetBotNode(req.BotID)
+	if err != nil {
+		return nil, err
+	}
+	if !bot.Enabled {
+		return nil, fmt.Errorf("bot node is disabled")
+	}
+	messageType, err := normalizeBotMessageType(req.MessageType)
+	if err != nil {
+		return nil, err
+	}
+	text := strings.TrimSpace(req.Text)
+	if text == "" {
+		return nil, fmt.Errorf("text is required")
+	}
+	if !utf8.ValidString(text) {
+		return nil, fmt.Errorf("text must be valid utf-8")
+	}
+	if len([]byte(text)) > botMaxTextBytes {
+		return nil, fmt.Errorf("text is too long, max %d bytes", botMaxTextBytes)
+	}
+	channelID := strings.TrimSpace(req.ChannelID)
+	if channelID == "" {
+		channelID = bot.DefaultChannelID
+	}
+	if channelID == "" {
+		return nil, fmt.Errorf("channel id is required")
+	}
+	toNodeNum, toNodeID, err := botMessageTarget(messageType, req)
+	if err != nil {
+		return nil, err
+	}
+	packetID, err := randomPacketID()
+	if err != nil {
+		return nil, err
+	}
+	fromNodeNum := uint32(bot.NodeNum)
+	raw, err := mqtpp.BuildTextMessageServiceEnvelope(mqtpp.TextMessageBuildOptions{
+		FromNodeNum: fromNodeNum,
+		ToNodeNum:   uint32(toNodeNum),
+		PacketID:    packetID,
+		ChannelID:   channelID,
+		GatewayID:   bot.NodeID,
+		Text:        text,
+		PSK:         s.key,
+		Encrypt:     true,
+		ViaMQTT:     true,
+	})
+	if err != nil {
+		return nil, err
+	}
+	topic := strings.Trim(bot.TopicPrefix, "/") + "/" + channelID + "/" + bot.NodeID
+	row := &botMessageRecord{
+		BotID:       bot.ID,
+		BotNodeID:   bot.NodeID,
+		BotNodeNum:  bot.NodeNum,
+		MessageType: messageType,
+		ChannelID:   channelID,
+		ToNodeID:    toNodeID,
+		ToNodeNum:   int64PtrOrNil(toNodeNum, messageType == botMessageTypeDirect),
+		Topic:       topic,
+		PacketID:    int64(packetID),
+		Text:        text,
+		PayloadLen:  int64(len(raw)),
+		Encrypted:   true,
+		Status:      botMessageStatusPending,
+		CreatedBy:   strings.TrimSpace(req.CreatedBy),
+	}
+	if err := s.store.InsertBotMessage(row); err != nil {
+		return nil, err
+	}
+	if s.server == nil {
+		_ = s.store.UpdateBotMessageStatus(row.ID, botMessageStatusFailed, "mqtt server is not configured", nil)
+		row.Status = botMessageStatusFailed
+		row.Error = "mqtt server is not configured"
+		return row, fmt.Errorf("mqtt server is not configured")
+	}
+	if err := s.server.Publish(topic, raw, false, 0); err != nil {
+		_ = s.store.UpdateBotMessageStatus(row.ID, botMessageStatusFailed, err.Error(), nil)
+		row.Status = botMessageStatusFailed
+		row.Error = err.Error()
+		return row, err
+	}
+	now := time.Now()
+	if err := s.store.UpdateBotMessageStatus(row.ID, botMessageStatusPublished, "", &now); err != nil {
+		return nil, err
+	}
+	row.Status = botMessageStatusPublished
+	row.Error = ""
+	row.PublishedAt = &now
+	return row, nil
+}
+
+func normalizeBotMessageType(value string) (string, error) {
+	switch strings.TrimSpace(value) {
+	case "", botMessageTypeChannel:
+		return botMessageTypeChannel, nil
+	case botMessageTypeDirect:
+		return botMessageTypeDirect, nil
+	default:
+		return "", fmt.Errorf("message type must be channel or direct")
+	}
+}
+
+func botMessageTarget(messageType string, req botSendTextRequest) (int64, *string, error) {
+	if messageType == botMessageTypeChannel {
+		return int64(mqtpp.NodeNumBroadcast), nil, nil
+	}
+	if req.ToNodeNum != nil && *req.ToNodeNum > 0 {
+		if err := validateBotNodeNum(*req.ToNodeNum); err != nil {
+			return 0, nil, err
+		}
+		nodeID := mqtpp.NodeNumToID(uint32(*req.ToNodeNum))
+		return *req.ToNodeNum, &nodeID, nil
+	}
+	toNodeID := strings.TrimSpace(req.ToNodeID)
+	if toNodeID == "" {
+		return 0, nil, fmt.Errorf("target node is required for direct message")
+	}
+	nodeNum, err := mqtpp.ParseNodeID(toNodeID)
+	if err != nil {
+		return 0, nil, err
+	}
+	if err := validateBotNodeNum(int64(nodeNum)); err != nil {
+		return 0, nil, err
+	}
+	normalized := mqtpp.NodeNumToID(nodeNum)
+	return int64(nodeNum), &normalized, nil
+}
+
+func randomPacketID() (uint32, error) {
+	for i := 0; i < 8; i++ {
+		var buf [4]byte
+		if _, err := rand.Read(buf[:]); err != nil {
+			return 0, err
+		}
+		id := binary.LittleEndian.Uint32(buf[:])
+		if id != 0 {
+			return id, nil
+		}
+	}
+	return 0, fmt.Errorf("generate packet id failed")
+}
+
+func int64PtrOrNil(value int64, ok bool) *int64 {
+	if !ok {
+		return nil
+	}
+	return &value
+}