feat: add im group mention flows

server/im_http.go

@@ -1115,6 +1115,93 @@ func serveIMFriends(wrt http.ResponseWriter, req *http.Request) {
 	writeIMSuccess(wrt, req, map[string]any{"items": payload, "next_cursor": nextCursor})
 }
 
+func serveIMGroupResource(wrt http.ResponseWriter, req *http.Request) {
+	topic, tail, ok := groupResourcePath(req.URL.Path)
+	if !ok {
+		writeIMError(wrt, req, http.StatusNotFound, 30004, imReasonMalformedRequest, "group route not found", nil)
+		return
+	}
+	if tail == "members" {
+		serveIMGroupMembers(wrt, req, topic)
+		return
+	}
+	writeIMError(wrt, req, http.StatusNotFound, 30004, imReasonMalformedRequest, "group route not found", nil)
+}
+
+func serveIMGroupMembers(wrt http.ResponseWriter, req *http.Request, topic string) {
+	if req.Method != http.MethodGet {
+		writeIMError(wrt, req, http.StatusMethodNotAllowed, 30002, imReasonMethodNotAllowed, "method not allowed", nil)
+		return
+	}
+	principal, ok := authenticateIMHTTPBearer(wrt, req)
+	if !ok {
+		return
+	}
+	if types.GetTopicCat(topic) != types.TopicCatGrp {
+		writeIMError(wrt, req, http.StatusBadRequest, 30000, imReasonMalformedRequest, "malformed request", map[string]any{"field": "topic"})
+		return
+	}
+	selfSub, err := store.Subs.Get(principal.TenantID, topic, principal.Uid, false)
+	if err != nil {
+		writeIMError(wrt, req, http.StatusInternalServerError, 90000, imReasonInternal, "internal error", nil)
+		return
+	}
+	selfAccess := types.ModeNone
+	if selfSub != nil {
+		selfAccess = selfSub.ModeGiven & selfSub.ModeWant
+	}
+	if selfSub == nil || !selfAccess.IsReader() {
+		writeIMError(wrt, req, http.StatusForbidden, 30005, imReasonPermissionDenied, "topic read permission required", nil)
+		return
+	}
+	limit := parseIMLimit(req.URL.Query().Get("limit"), 30, 100)
+	cursor, err := parseIMNonNegativeCursor(req.URL.Query().Get("cursor"))
+	if err != nil {
+		writeIMError(wrt, req, http.StatusBadRequest, 30000, imReasonMalformedRequest, "malformed request", map[string]any{"field": "cursor"})
+		return
+	}
+	query := strings.TrimSpace(req.URL.Query().Get("query"))
+	mentionableOnly := parseIMBool(req.URL.Query().Get("mentionable"))
+	members, err := store.Topics.GetUsers(principal.TenantID, topic, &types.QueryOpt{Limit: 1000})
+	if err != nil {
+		writeIMError(wrt, req, http.StatusInternalServerError, 90000, imReasonInternal, "internal error", nil)
+		return
+	}
+	items := make([]map[string]any, 0, limit)
+	seen := 0
+	nextCursor := ""
+	for _, member := range members {
+		access := member.ModeGiven & member.ModeWant
+		mentionable := access.IsJoiner() && access.IsReader()
+		if mentionableOnly && !mentionable {
+			continue
+		}
+		item := groupMemberPayload(member, mentionable)
+		if query != "" && !groupMemberMatches(item, query) {
+			continue
+		}
+		if seen < cursor {
+			seen++
+			continue
+		}
+		if len(items) == limit {
+			nextCursor = strconv.Itoa(seen)
+			break
+		}
+		items = append(items, item)
+		seen++
+	}
+	permissions := map[string]any{
+		"can_mention_all": selfAccess.IsAdmin(),
+	}
+	writeIMSuccess(wrt, req, map[string]any{
+		"topic":       topic,
+		"items":       items,
+		"next_cursor": nextCursor,
+		"permissions": permissions,
+	})
+}
+
 func serveIMFriendRequestAction(wrt http.ResponseWriter, req *http.Request) {
 	if req.Method != http.MethodPost {
 		writeIMError(wrt, req, http.StatusMethodNotAllowed, 30002, imReasonMethodNotAllowed, "method not allowed", nil)
@@ -1525,6 +1612,27 @@ func parseIMLimit(raw string, fallback, max int) int {
 	return limit
 }
 
+func parseIMNonNegativeCursor(raw string) (int, error) {
+	raw = strings.TrimSpace(raw)
+	if raw == "" {
+		return 0, nil
+	}
+	cursor, err := strconv.Atoi(raw)
+	if err != nil || cursor < 0 {
+		return 0, errors.New("invalid cursor")
+	}
+	return cursor, nil
+}
+
+func parseIMBool(raw string) bool {
+	switch strings.ToLower(strings.TrimSpace(raw)) {
+	case "1", "true", "yes", "y":
+		return true
+	default:
+		return false
+	}
+}
+
 func conversationMatches(sub types.Subscription, query string) bool {
 	if strings.Contains(strings.ToLower(sub.Topic), query) {
 		return true
@@ -1560,6 +1668,45 @@ func receiptMemberPayload(sub types.Subscription) map[string]any {
 	}
 }
 
+func groupMemberPayload(sub types.Subscription, mentionable bool) map[string]any {
+	access := sub.ModeGiven & sub.ModeWant
+	userID := types.ParseUserId(sub.User)
+	user := &types.User{ObjHeader: types.ObjHeader{Id: userID.String()}, Public: sub.GetPublic(), Trusted: sub.GetTrusted()}
+	data := userSummaryPayload(user, "")
+	data["role"] = groupMemberRole(access)
+	data["mentionable"] = mentionable
+	data["acs"] = map[string]any{
+		"mode":  access.String(),
+		"want":  sub.ModeWant.String(),
+		"given": sub.ModeGiven.String(),
+	}
+	return data
+}
+
+func groupMemberRole(access types.AccessMode) string {
+	switch {
+	case access.IsOwner():
+		return "owner"
+	case access.IsAdmin():
+		return "admin"
+	default:
+		return "member"
+	}
+}
+
+func groupMemberMatches(item map[string]any, query string) bool {
+	query = strings.ToLower(strings.TrimSpace(query))
+	if query == "" {
+		return true
+	}
+	for _, key := range []string{"display_name", "user_id"} {
+		if value, ok := item[key]; ok && strings.Contains(strings.ToLower(fmt.Sprint(value)), query) {
+			return true
+		}
+	}
+	return false
+}
+
 func authorizeIMMessageMutation(principal *imPrincipal, topic string, seq int, allowAdmin bool) (*types.Message, bool, error) {
 	if principal == nil {
 		return nil, false, types.ErrPermissionDenied
@@ -2068,6 +2215,20 @@ func conversationContextTopicFromPath(path string) string {
 	return strings.TrimSuffix(strings.TrimPrefix(path[idx:], prefix), suffix)
 }
 
+func groupResourcePath(path string) (string, string, bool) {
+	const prefix = "/v1/im/groups/"
+	idx := strings.Index(path, prefix)
+	if idx < 0 {
+		return "", "", false
+	}
+	rest := strings.TrimPrefix(path[idx:], prefix)
+	topic, tail, ok := strings.Cut(rest, "/")
+	if !ok || topic == "" || tail == "" {
+		return "", "", false
+	}
+	return topic, strings.Trim(tail, "/"), true
+}
+
 func friendRequestActionFromPath(path string) (string, string) {
 	const prefix = "/v1/im/friend-requests/"
 	idx := strings.Index(path, prefix)