fix group fragmented message parse error.

client/client.go

@@ -54,6 +54,7 @@ type QQClient struct {
 
 	lastMessageSeq         int32
 	lastMessageSeqTmp      sync.Map
+	groupMsgBuilders       sync.Map
 	onlinePushCache        []int16 // reset on reconnect
 	requestPacketRequestId int32
 	messageSeq             int32

client/decoders.go

@@ -229,7 +229,7 @@ func decodeMessageSvcPacket(c *QQClient, _ uint16, payload []byte) (interface{},
 	return nil, err
 }
 
-func decodeGroupMessagePacket(c *QQClient, _ uint16, payload []byte) (interface{}, error) {
+func decodeGroupMessagePacket(c *QQClient, seq uint16, payload []byte) (interface{}, error) {
 	pkt := msg.PushMessagePacket{}
 	err := proto.Unmarshal(payload, &pkt)
 	if err != nil {
@@ -242,6 +242,25 @@ func decodeGroupMessagePacket(c *QQClient, _ uint16, payload []byte) (interface{
 		})
 		return nil, nil
 	}
+	if pkt.Message.Content.PkgNum > 1 {
+		var builder *groupMessageBuilder
+		i, ok := c.groupMsgBuilders.Load(pkt.Message.Content.DivSeq)
+		if !ok {
+			builder = &groupMessageBuilder{
+				MessageSeq:   pkt.Message.Content.DivSeq,
+				MessageCount: pkt.Message.Content.PkgNum,
+			}
+			c.groupMsgBuilders.Store(pkt.Message.Content.DivSeq, builder)
+		} else {
+			builder = i.(*groupMessageBuilder)
+		}
+		builder.MessageSlices = append(builder.MessageSlices, pkt.Message)
+		if int32(len(builder.MessageSlices)) >= builder.MessageCount {
+			c.groupMsgBuilders.Delete(pkt.Message.Content.DivSeq)
+			c.dispatchGroupMessage(c.parseGroupMessage(builder.build()))
+		}
+		return nil, nil
+	}
 	c.dispatchGroupMessage(c.parseGroupMessage(pkt.Message))
 	return nil, nil
 }

client/global.go

@@ -8,6 +8,7 @@ import (
 	"github.com/Mrs4s/MiraiGo/message"
 	"google.golang.org/protobuf/proto"
 	"math/rand"
+	"sort"
 )
 
 type DeviceInfo struct {
@@ -44,6 +45,12 @@ type Version struct {
 	Sdk         uint32
 }
 
+type groupMessageBuilder struct {
+	MessageSeq    int32
+	MessageCount  int32
+	MessageSlices []*msg.Message
+}
+
 var SystemDeviceInfo = &DeviceInfo{
 	Display:     []byte("MIRAI.123456.001"),
 	Product:     []byte("mirai"),
@@ -227,3 +234,14 @@ func parseMessageElems(elems []*msg.Elem) []message.IMessageElement {
 	}
 	return res
 }
+
+func (b *groupMessageBuilder) build() *msg.Message {
+	sort.Slice(b.MessageSlices, func(i, j int) bool {
+		return b.MessageSlices[i].Content.PkgIndex < b.MessageSlices[i].Content.PkgIndex
+	})
+	base := b.MessageSlices[0]
+	for _, m := range b.MessageSlices[1:] {
+		base.Body.RichText.Elems = append(base.Body.RichText.Elems, m.Body.RichText.Elems...)
+	}
+	return base
+}

client/pb/msg/msg.proto

@@ -109,6 +109,7 @@ message UinPairMessage {
 
 message Message {
     MessageHead head = 1;
+    ContentHead content = 2;
     MessageBody body = 3;   
 }