fix: update blocklist using LID with fallback to GetUserInfo

Author: zennn08

user.go

@@ -12,7 +12,9 @@ import (
 	"errors"
 	"fmt"
 	"slices"
+	"strconv"
 	"strings"
+	"time"
 
 	"google.golang.org/protobuf/proto"
 
@@ -942,16 +944,52 @@ func (cli *Client) GetBlocklist(ctx context.Context) (*types.Blocklist, error) {
 
 // UpdateBlocklist updates the user's block list and returns the updated list.
 func (cli *Client) UpdateBlocklist(ctx context.Context, jid types.JID, action events.BlocklistChangeAction) (*types.Blocklist, error) {
+	var lidJID, pnJID types.JID
+
+	if jid.Server == types.DefaultUserServer {
+		pnJID = jid
+		lid, err := cli.Store.LIDs.GetLIDForPN(ctx, jid)
+		if err != nil {
+			return nil, fmt.Errorf("failed to get LID for PN %s: %w", jid, err)
+		}
+		if lid.IsEmpty() {
+			info, err := cli.GetUserInfo(ctx, []types.JID{jid})
+			if err != nil {
+				return nil, fmt.Errorf("failed to get user info for %s to fill LID cache: %w", jid, err)
+			}
+			lid = info[jid].LID
+			if lid.IsEmpty() {
+				return nil, fmt.Errorf("no LID found for %s from server", jid)
+			}
+		}
+		lidJID = lid
+	} else if jid.Server == types.HiddenUserServer {
+		lidJID = jid
+		if action == events.BlocklistChangeActionBlock {
+			pn, err := cli.Store.LIDs.GetPNForLID(ctx, jid)
+			if err != nil {
+				return nil, fmt.Errorf("failed to resolve PN for %s: %w", jid, err)
+			}
+			pnJID = pn
+		}
+	}
+
+	itemAttrs := waBinary.Attrs{
+		"jid":    lidJID,
+		"action": string(action),
+		"dhash":  strconv.FormatInt(time.Now().UnixMilli(), 10),
+	}
+	if action == events.BlocklistChangeActionBlock && !pnJID.IsEmpty() {
+		itemAttrs["pn_jid"] = pnJID
+	}
+
 	resp, err := cli.sendIQ(ctx, infoQuery{
 		Namespace: "blocklist",
 		Type:      iqSet,
 		To:        types.ServerJID,
 		Content: []waBinary.Node{{
-			Tag: "item",
-			Attrs: waBinary.Attrs{
-				"jid":    jid,
-				"action": string(action),
-			},
+			Tag:   "item",
+			Attrs: itemAttrs,
 		}},
 	})
 	if err != nil {