fix: address 3 blocking review findings for IRC protocol listener

1. ISUPPORT/applyChannelModes: extend IRC MODE handler to support +i/-i,
   +s/-s, +n/-n (routed through svc.SetChannelFlag), and +H/-H (hashcash
   bits with parameter parsing). Add 'n' (no external messages) as a
   proper DB-backed channel flag with is_no_external column (default: on).
   Update IRC ISUPPORT to CHANMODES=,,H,imnst to match actual support.

2. QueryChannelMode: rewrite to return complete mode string including all
   boolean flags (n, i, m, s, t) and parameterized modes (k, l, H),
   matching the HTTP handler's buildChannelModeString logic. Simplify
   buildChannelModeString to delegate to QueryChannelMode for consistency.

3. Service struct encapsulation: change exported fields (DB, Broker,
   Config, Log) to unexported (db, broker, config, log). Add NewTestService
   constructor for use by external test packages. Update ircserver
   export_test.go to use the new constructor.

Closes #89

internal/db/queries.go

@@ -2165,6 +2165,52 @@ func (database *Database) SetChannelSecret(
 	return nil
 }
 
+// --- No External Messages (+n) ---
+
+// IsChannelNoExternal checks if a channel has +n mode.
+func (database *Database) IsChannelNoExternal(
+	ctx context.Context,
+	channelID int64,
+) (bool, error) {
+	var isNoExternal int
+
+	err := database.conn.QueryRowContext(ctx,
+		`SELECT is_no_external FROM channels
+		 WHERE id = ?`,
+		channelID,
+	).Scan(&isNoExternal)
+	if err != nil {
+		return false, fmt.Errorf(
+			"check no external: %w", err,
+		)
+	}
+
+	return isNoExternal != 0, nil
+}
+
+// SetChannelNoExternal sets or unsets +n mode.
+func (database *Database) SetChannelNoExternal(
+	ctx context.Context,
+	channelID int64,
+	noExternal bool,
+) error {
+	val := 0
+	if noExternal {
+		val = 1
+	}
+
+	_, err := database.conn.ExecContext(ctx,
+		`UPDATE channels
+		 SET is_no_external = ?, updated_at = ?
+		 WHERE id = ?`,
+		val, time.Now(), channelID)
+	if err != nil {
+		return fmt.Errorf("set no external: %w", err)
+	}
+
+	return nil
+}
+
 // ListAllChannelsWithCountsFiltered returns all channels
 // with member counts, excluding secret channels that
 // the given session is not a member of.

internal/db/schema/001_initial.sql

@@ -44,6 +44,7 @@ CREATE TABLE IF NOT EXISTS channels (
     is_topic_locked INTEGER NOT NULL DEFAULT 1,
     is_invite_only INTEGER NOT NULL DEFAULT 0,
     is_secret INTEGER NOT NULL DEFAULT 0,
+    is_no_external INTEGER NOT NULL DEFAULT 1,
     channel_key TEXT NOT NULL DEFAULT '',
     user_limit INTEGER NOT NULL DEFAULT 0,
     created_at DATETIME DEFAULT CURRENT_TIMESTAMP,

internal/handlers/api.go

@@ -2016,62 +2016,14 @@ func (hdlr *Handlers) handleChannelMode(
 }
 
 // buildChannelModeString constructs the current mode
-// string for a channel, including +n (always on), +t, +m,
+// string for a channel by delegating to the service
-// +i, +s, +k, +l, and +H with their parameters.
+// layer's QueryChannelMode, which returns the complete
+// mode string including all flags and parameters.
 func (hdlr *Handlers) buildChannelModeString(
 	ctx context.Context,
 	chID int64,
 ) string {
-	modes := "+n"
+	return hdlr.svc.QueryChannelMode(ctx, chID)
-
-	isInviteOnly, ioErr := hdlr.params.Database.
-		IsChannelInviteOnly(ctx, chID)
-	if ioErr == nil && isInviteOnly {
-		modes += "i"
-	}
-
-	isModerated, modErr := hdlr.params.Database.
-		IsChannelModerated(ctx, chID)
-	if modErr == nil && isModerated {
-		modes += "m"
-	}
-
-	isSecret, secErr := hdlr.params.Database.
-		IsChannelSecret(ctx, chID)
-	if secErr == nil && isSecret {
-		modes += "s"
-	}
-
-	isTopicLocked, tlErr := hdlr.params.Database.
-		IsChannelTopicLocked(ctx, chID)
-	if tlErr == nil && isTopicLocked {
-		modes += "t"
-	}
-
-	var modeParams string
-
-	key, keyErr := hdlr.params.Database.
-		GetChannelKey(ctx, chID)
-	if keyErr == nil && key != "" {
-		modes += "k"
-		modeParams += " " + key
-	}
-
-	limit, limErr := hdlr.params.Database.
-		GetChannelUserLimit(ctx, chID)
-	if limErr == nil && limit > 0 {
-		modes += "l"
-		modeParams += " " + strconv.Itoa(limit)
-	}
-
-	bits, bitsErr := hdlr.params.Database.
-		GetChannelHashcashBits(ctx, chID)
-	if bitsErr == nil && bits > 0 {
-		modes += "H"
-		modeParams += " " + strconv.Itoa(bits)
-	}
-
-	return modes + modeParams
 }
 
 // queryChannelMode sends RPL_CHANNELMODEIS and

internal/ircserver/commands.go

@@ -490,6 +490,124 @@ func (c *Conn) handleChannelMode(
 	)
 }
 
+// modeResult holds the delta strings produced by a
+// single mode-char application.
+type modeResult struct {
+	applied     string
+	appliedArgs string
+	consumed    int
+	skip        bool
+}
+
+// applyHashcashMode handles +H/-H (hashcash difficulty).
+func (c *Conn) applyHashcashMode(
+	ctx context.Context,
+	chID int64,
+	adding bool,
+	args []string,
+	argIdx int,
+) modeResult {
+	if !adding {
+		_ = c.database.SetChannelHashcashBits(
+			ctx, chID, 0,
+		)
+
+		return modeResult{
+			applied:     "-H",
+			appliedArgs: "",
+			consumed:    0,
+			skip:        false,
+		}
+	}
+
+	if argIdx >= len(args) {
+		return modeResult{
+			applied:     "",
+			appliedArgs: "",
+			consumed:    0,
+			skip:        true,
+		}
+	}
+
+	bitsStr := args[argIdx]
+
+	bits, parseErr := strconv.Atoi(bitsStr)
+	if parseErr != nil ||
+		bits < 1 || bits > maxHashcashBits {
+		c.sendNumeric(
+			irc.ErrUnknownMode, "H",
+			"is unknown mode char to me",
+		)
+
+		return modeResult{
+			applied:     "",
+			appliedArgs: "",
+			consumed:    1,
+			skip:        true,
+		}
+	}
+
+	_ = c.database.SetChannelHashcashBits(
+		ctx, chID, bits,
+	)
+
+	return modeResult{
+		applied:     "+H",
+		appliedArgs: " " + bitsStr,
+		consumed:    1,
+		skip:        false,
+	}
+}
+
+// applyMemberMode handles +o/-o and +v/-v.
+func (c *Conn) applyMemberMode(
+	ctx context.Context,
+	chID int64,
+	channel string,
+	modeChar rune,
+	adding bool,
+	args []string,
+	argIdx int,
+) modeResult {
+	if argIdx >= len(args) {
+		return modeResult{
+			applied:     "",
+			appliedArgs: "",
+			consumed:    0,
+			skip:        true,
+		}
+	}
+
+	targetNick := args[argIdx]
+
+	err := c.svc.ApplyMemberMode(
+		ctx, chID, channel,
+		targetNick, modeChar, adding,
+	)
+	if err != nil {
+		c.sendIRCError(err)
+
+		return modeResult{
+			applied:     "",
+			appliedArgs: "",
+			consumed:    1,
+			skip:        true,
+		}
+	}
+
+	prefix := "+"
+	if !adding {
+		prefix = "-"
+	}
+
+	return modeResult{
+		applied:     prefix + string(modeChar),
+		appliedArgs: " " + targetNick,
+		consumed:    1,
+		skip:        false,
+	}
+}
+
 // applyChannelModes applies mode changes using the
 // service for individual mode operations.
 func (c *Conn) applyChannelModes(
@@ -505,52 +623,57 @@ func (c *Conn) applyChannelModes(
 	appliedArgs := ""
 
 	for _, modeChar := range modeStr {
+		var res modeResult
+
 		switch modeChar {
 		case '+':
 			adding = true
+
+			continue
 		case '-':
 			adding = false
-		case 'm', 't':
+
+			continue
+		case 'i', 'm', 'n', 's', 't':
 			_ = c.svc.SetChannelFlag(
 				ctx, chID, modeChar, adding,
 			)
 
-			if adding {
+			prefix := "+"
-				applied += "+" + string(modeChar)
+			if !adding {
-			} else {
+				prefix = "-"
-				applied += "-" + string(modeChar)
-			}
-		case 'o', 'v':
-			if argIdx >= len(args) {
-				break
 			}
 
-			targetNick := args[argIdx]
+			res = modeResult{
-			argIdx++
+				applied:     prefix + string(modeChar),
-
+				appliedArgs: "",
-			err := c.svc.ApplyMemberMode(
+				consumed:    0,
-				ctx, chID, channel,
+				skip:        false,
-				targetNick, modeChar, adding,
+			}
+		case 'H':
+			res = c.applyHashcashMode(
+				ctx, chID, adding, args, argIdx,
+			)
+		case 'o', 'v':
+			res = c.applyMemberMode(
+				ctx, chID, channel,
+				modeChar, adding, args, argIdx,
 			)
-			if err != nil {
-				c.sendIRCError(err)
-
-				continue
-			}
-
-			if adding {
-				applied += "+" + string(modeChar)
-			} else {
-				applied += "-" + string(modeChar)
-			}
-
-			appliedArgs += " " + targetNick
 		default:
 			c.sendNumeric(
 				irc.ErrUnknownMode,
 				string(modeChar),
 				"is unknown mode char to me",
 			)
+
+			continue
+		}
+
+		argIdx += res.consumed
+
+		if !res.skip {
+			applied += res.applied
+			appliedArgs += res.appliedArgs
 		}
 	}
 

internal/ircserver/conn.go

@@ -28,6 +28,7 @@ const (
 	pongDeadline    = 30 * time.Second
 	maxNickLen      = 32
 	minPasswordLen  = 8
+	maxHashcashBits = 40
 )
 
 // cmdHandler is the signature for registered IRC command
@@ -434,7 +435,7 @@ func (c *Conn) deliverWelcome() {
 		"CHANTYPES=#",
 		"NICKLEN=32",
 		"PREFIX=(ov)@+",
-		"CHANMODES=,,H,mnst",
+		"CHANMODES=,,H,imnst",
 		"NETWORK="+c.serverSfx,
 		"are supported by this server",
 	)

internal/ircserver/export_test.go

@@ -19,12 +19,9 @@ func NewTestServer(
 	database *db.Database,
 	brk *broker.Broker,
 ) *Server {
-	svc := &service.Service{
+	svc := service.NewTestService(
-		DB:     database,
+		database, brk, cfg, log,
-		Broker: brk,
+	)
-		Config: cfg,
-		Log:    log,
-	}
 
 	return &Server{ //nolint:exhaustruct
 		log:      log,

internal/service/service.go

@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"log/slog"
+	"strconv"
 	"strings"
 
 	"git.eeqj.de/sneak/neoirc/internal/broker"
@@ -30,19 +31,35 @@ type Params struct {
 
 // Service provides shared business logic for IRC commands.
 type Service struct {
-	DB     *db.Database
+	db     *db.Database
-	Broker *broker.Broker
+	broker *broker.Broker
-	Config *config.Config
+	config *config.Config
-	Log    *slog.Logger
+	log    *slog.Logger
 }
 
 // New creates a new Service.
 func New(params Params) *Service {
 	return &Service{
-		DB:     params.Database,
+		db:     params.Database,
-		Broker: params.Broker,
+		broker: params.Broker,
-		Config: params.Config,
+		config: params.Config,
-		Log:    params.Logger.Get(),
+		log:    params.Logger.Get(),
+	}
+}
+
+// NewTestService creates a Service for use in tests
+// outside the service package.
+func NewTestService(
+	database *db.Database,
+	brk *broker.Broker,
+	cfg *config.Config,
+	log *slog.Logger,
+) *Service {
+	return &Service{
+		db:     database,
+		broker: brk,
+		config: cfg,
+		log:    log,
 	}
 }
 
@@ -76,7 +93,7 @@ func (s *Service) FanOut(
 	params, body, meta json.RawMessage,
 	sessionIDs []int64,
 ) (int64, string, error) {
-	dbID, msgUUID, err := s.DB.InsertMessage(
+	dbID, msgUUID, err := s.db.InsertMessage(
 		ctx, command, from, to, params, body, meta,
 	)
 	if err != nil {
@@ -84,8 +101,8 @@ func (s *Service) FanOut(
 	}
 
 	for _, sid := range sessionIDs {
-		_ = s.DB.EnqueueToSession(ctx, sid, dbID)
+		_ = s.db.EnqueueToSession(ctx, sid, dbID)
-		s.Broker.Notify(sid)
+		s.broker.Notify(sid)
 	}
 
 	return dbID, msgUUID, nil
@@ -120,7 +137,7 @@ func (s *Service) SendChannelMessage(
 	nick, command, channel string,
 	body, meta json.RawMessage,
 ) (int64, string, error) {
-	chID, err := s.DB.GetChannelByName(ctx, channel)
+	chID, err := s.db.GetChannelByName(ctx, channel)
 	if err != nil {
 		return 0, "", &IRCError{
 			irc.ErrNoSuchChannel,
@@ -129,7 +146,7 @@ func (s *Service) SendChannelMessage(
 		}
 	}
 
-	isMember, _ := s.DB.IsChannelMember(
+	isMember, _ := s.db.IsChannelMember(
 		ctx, chID, sessionID,
 	)
 	if !isMember {
@@ -141,7 +158,7 @@ func (s *Service) SendChannelMessage(
 	}
 
 	// Ban check — banned users cannot send messages.
-	isBanned, banErr := s.DB.IsSessionBanned(
+	isBanned, banErr := s.db.IsSessionBanned(
 		ctx, chID, sessionID,
 	)
 	if banErr == nil && isBanned {
@@ -152,12 +169,12 @@ func (s *Service) SendChannelMessage(
 		}
 	}
 
-	moderated, _ := s.DB.IsChannelModerated(ctx, chID)
+	moderated, _ := s.db.IsChannelModerated(ctx, chID)
 	if moderated {
-		isOp, _ := s.DB.IsChannelOperator(
+		isOp, _ := s.db.IsChannelOperator(
 			ctx, chID, sessionID,
 		)
-		isVoiced, _ := s.DB.IsChannelVoiced(
+		isVoiced, _ := s.db.IsChannelVoiced(
 			ctx, chID, sessionID,
 		)
 
@@ -170,7 +187,7 @@ func (s *Service) SendChannelMessage(
 		}
 	}
 
-	memberIDs, _ := s.DB.GetChannelMemberIDs(ctx, chID)
+	memberIDs, _ := s.db.GetChannelMemberIDs(ctx, chID)
 	recipients := excludeSession(memberIDs, sessionID)
 
 	dbID, uuid, fanErr := s.FanOut(
@@ -193,7 +210,7 @@ func (s *Service) SendDirectMessage(
 	nick, command, target string,
 	body, meta json.RawMessage,
 ) (*DirectMsgResult, error) {
-	targetSID, err := s.DB.GetSessionByNick(ctx, target)
+	targetSID, err := s.db.GetSessionByNick(ctx, target)
 	if err != nil {
 		return nil, &IRCError{
 			irc.ErrNoSuchNick,
@@ -202,7 +219,7 @@ func (s *Service) SendDirectMessage(
 		}
 	}
 
-	away, _ := s.DB.GetAway(ctx, targetSID)
+	away, _ := s.db.GetAway(ctx, targetSID)
 
 	recipients := []int64{targetSID}
 	if targetSID != sessionID {
@@ -228,19 +245,19 @@ func (s *Service) JoinChannel(
 	sessionID int64,
 	nick, channel, suppliedKey string,
 ) (*JoinResult, error) {
-	chID, err := s.DB.GetOrCreateChannel(ctx, channel)
+	chID, err := s.db.GetOrCreateChannel(ctx, channel)
 	if err != nil {
 		return nil, fmt.Errorf("get/create channel: %w", err)
 	}
 
-	memberCount, countErr := s.DB.CountChannelMembers(
+	memberCount, countErr := s.db.CountChannelMembers(
 		ctx, chID,
 	)
 	isCreator := countErr == nil && memberCount == 0
 
 	if !isCreator {
 		if joinErr := checkJoinRestrictions(
-			ctx, s.DB, chID, sessionID,
+			ctx, s.db, chID, sessionID,
 			channel, suppliedKey, memberCount,
 		); joinErr != nil {
 			return nil, joinErr
@@ -248,11 +265,11 @@ func (s *Service) JoinChannel(
 	}
 
 	if isCreator {
-		err = s.DB.JoinChannelAsOperator(
+		err = s.db.JoinChannelAsOperator(
 			ctx, chID, sessionID,
 		)
 	} else {
-		err = s.DB.JoinChannel(ctx, chID, sessionID)
+		err = s.db.JoinChannel(ctx, chID, sessionID)
 	}
 
 	if err != nil {
@@ -260,9 +277,9 @@ func (s *Service) JoinChannel(
 	}
 
 	// Clear invite after successful join.
-	_ = s.DB.ClearChannelInvite(ctx, chID, sessionID)
+	_ = s.db.ClearChannelInvite(ctx, chID, sessionID)
 
-	memberIDs, _ := s.DB.GetChannelMemberIDs(ctx, chID)
+	memberIDs, _ := s.db.GetChannelMemberIDs(ctx, chID)
 	body, _ := json.Marshal([]string{channel}) //nolint:errchkjson
 
 	_, _, _ = s.FanOut( //nolint:dogsled // fire-and-forget broadcast
@@ -284,7 +301,7 @@ func (s *Service) PartChannel(
 	sessionID int64,
 	nick, channel, reason string,
 ) error {
-	chID, err := s.DB.GetChannelByName(ctx, channel)
+	chID, err := s.db.GetChannelByName(ctx, channel)
 	if err != nil {
 		return &IRCError{
 			irc.ErrNoSuchChannel,
@@ -293,7 +310,7 @@ func (s *Service) PartChannel(
 		}
 	}
 
-	isMember, _ := s.DB.IsChannelMember(
+	isMember, _ := s.db.IsChannelMember(
 		ctx, chID, sessionID,
 	)
 	if !isMember {
@@ -304,7 +321,7 @@ func (s *Service) PartChannel(
 		}
 	}
 
-	memberIDs, _ := s.DB.GetChannelMemberIDs(ctx, chID)
+	memberIDs, _ := s.db.GetChannelMemberIDs(ctx, chID)
 	recipients := excludeSession(memberIDs, sessionID)
 	body, _ := json.Marshal([]string{reason}) //nolint:errchkjson
 
@@ -313,8 +330,8 @@ func (s *Service) PartChannel(
 		nil, body, nil, recipients,
 	)
 
-	s.DB.PartChannel(ctx, chID, sessionID) //nolint:errcheck,gosec
+	s.db.PartChannel(ctx, chID, sessionID) //nolint:errcheck,gosec
-	s.DB.DeleteChannelIfEmpty(ctx, chID)   //nolint:errcheck,gosec
+	s.db.DeleteChannelIfEmpty(ctx, chID)   //nolint:errcheck,gosec
 
 	return nil
 }
@@ -326,7 +343,7 @@ func (s *Service) SetTopic(
 	sessionID int64,
 	nick, channel, topic string,
 ) error {
-	chID, err := s.DB.GetChannelByName(ctx, channel)
+	chID, err := s.db.GetChannelByName(ctx, channel)
 	if err != nil {
 		return &IRCError{
 			irc.ErrNoSuchChannel,
@@ -335,7 +352,7 @@ func (s *Service) SetTopic(
 		}
 	}
 
-	isMember, _ := s.DB.IsChannelMember(
+	isMember, _ := s.db.IsChannelMember(
 		ctx, chID, sessionID,
 	)
 	if !isMember {
@@ -346,9 +363,9 @@ func (s *Service) SetTopic(
 		}
 	}
 
-	topicLocked, _ := s.DB.IsChannelTopicLocked(ctx, chID)
+	topicLocked, _ := s.db.IsChannelTopicLocked(ctx, chID)
 	if topicLocked {
-		isOp, _ := s.DB.IsChannelOperator(
+		isOp, _ := s.db.IsChannelOperator(
 			ctx, chID, sessionID,
 		)
 		if !isOp {
@@ -360,15 +377,15 @@ func (s *Service) SetTopic(
 		}
 	}
 
-	if setErr := s.DB.SetTopic(
+	if setErr := s.db.SetTopic(
 		ctx, channel, topic,
 	); setErr != nil {
 		return fmt.Errorf("set topic: %w", setErr)
 	}
 
-	_ = s.DB.SetTopicMeta(ctx, channel, topic, nick)
+	_ = s.db.SetTopicMeta(ctx, channel, topic, nick)
 
-	memberIDs, _ := s.DB.GetChannelMemberIDs(ctx, chID)
+	memberIDs, _ := s.db.GetChannelMemberIDs(ctx, chID)
 	body, _ := json.Marshal([]string{topic}) //nolint:errchkjson
 
 	_, _, _ = s.FanOut( //nolint:dogsled // fire-and-forget broadcast
@@ -387,7 +404,7 @@ func (s *Service) KickUser(
 	sessionID int64,
 	nick, channel, targetNick, reason string,
 ) error {
-	chID, err := s.DB.GetChannelByName(ctx, channel)
+	chID, err := s.db.GetChannelByName(ctx, channel)
 	if err != nil {
 		return &IRCError{
 			irc.ErrNoSuchChannel,
@@ -396,7 +413,7 @@ func (s *Service) KickUser(
 		}
 	}
 
-	isOp, _ := s.DB.IsChannelOperator(
+	isOp, _ := s.db.IsChannelOperator(
 		ctx, chID, sessionID,
 	)
 	if !isOp {
@@ -407,7 +424,7 @@ func (s *Service) KickUser(
 		}
 	}
 
-	targetSID, err := s.DB.GetSessionByNick(
+	targetSID, err := s.db.GetSessionByNick(
 		ctx, targetNick,
 	)
 	if err != nil {
@@ -418,7 +435,7 @@ func (s *Service) KickUser(
 		}
 	}
 
-	isMember, _ := s.DB.IsChannelMember(
+	isMember, _ := s.db.IsChannelMember(
 		ctx, chID, targetSID,
 	)
 	if !isMember {
@@ -429,7 +446,7 @@ func (s *Service) KickUser(
 		}
 	}
 
-	memberIDs, _ := s.DB.GetChannelMemberIDs(ctx, chID)
+	memberIDs, _ := s.db.GetChannelMemberIDs(ctx, chID)
 	body, _ := json.Marshal([]string{reason}) //nolint:errchkjson
 	params, _ := json.Marshal(                //nolint:errchkjson
 		[]string{targetNick},
@@ -440,8 +457,8 @@ func (s *Service) KickUser(
 		params, body, nil, memberIDs,
 	)
 
-	s.DB.PartChannel(ctx, chID, targetSID) //nolint:errcheck,gosec
+	s.db.PartChannel(ctx, chID, targetSID) //nolint:errcheck,gosec
-	s.DB.DeleteChannelIfEmpty(ctx, chID)   //nolint:errcheck,gosec
+	s.db.DeleteChannelIfEmpty(ctx, chID)   //nolint:errcheck,gosec
 
 	return nil
 }
@@ -453,7 +470,7 @@ func (s *Service) ChangeNick(
 	sessionID int64,
 	oldNick, newNick string,
 ) error {
-	err := s.DB.ChangeNick(ctx, sessionID, newNick)
+	err := s.db.ChangeNick(ctx, sessionID, newNick)
 	if err != nil {
 		if strings.Contains(err.Error(), "UNIQUE") ||
 			db.IsUniqueConstraintError(err) {
@@ -485,7 +502,7 @@ func (s *Service) BroadcastQuit(
 	sessionID int64,
 	nick, reason string,
 ) {
-	channels, err := s.DB.GetSessionChannels(
+	channels, err := s.db.GetSessionChannels(
 		ctx, sessionID,
 	)
 	if err != nil {
@@ -495,7 +512,7 @@ func (s *Service) BroadcastQuit(
 	notified := make(map[int64]bool)
 
 	for _, ch := range channels {
-		memberIDs, memErr := s.DB.GetChannelMemberIDs(
+		memberIDs, memErr := s.db.GetChannelMemberIDs(
 			ctx, ch.ID,
 		)
 		if memErr != nil {
@@ -526,11 +543,11 @@ func (s *Service) BroadcastQuit(
 	}
 
 	for _, ch := range channels {
-		s.DB.PartChannel(ctx, ch.ID, sessionID) //nolint:errcheck,gosec
+		s.db.PartChannel(ctx, ch.ID, sessionID) //nolint:errcheck,gosec
-		s.DB.DeleteChannelIfEmpty(ctx, ch.ID)   //nolint:errcheck,gosec
+		s.db.DeleteChannelIfEmpty(ctx, ch.ID)   //nolint:errcheck,gosec
 	}
 
-	s.DB.DeleteSession(ctx, sessionID) //nolint:errcheck,gosec
+	s.db.DeleteSession(ctx, sessionID) //nolint:errcheck,gosec
 }
 
 // SetAway sets or clears the away message. Returns true
@@ -540,7 +557,7 @@ func (s *Service) SetAway(
 	sessionID int64,
 	message string,
 ) (bool, error) {
-	err := s.DB.SetAway(ctx, sessionID, message)
+	err := s.db.SetAway(ctx, sessionID, message)
 	if err != nil {
 		return false, fmt.Errorf("set away: %w", err)
 	}
@@ -555,8 +572,8 @@ func (s *Service) Oper(
 	sessionID int64,
 	name, password string,
 ) error {
-	cfgName := s.Config.OperName
+	cfgName := s.config.OperName
-	cfgPassword := s.Config.OperPassword
+	cfgPassword := s.config.OperPassword
 
 	// Use constant-time comparison and return the same
 	// error for all failures to prevent information
@@ -575,7 +592,7 @@ func (s *Service) Oper(
 		}
 	}
 
-	_ = s.DB.SetSessionOper(ctx, sessionID, true)
+	_ = s.db.SetSessionOper(ctx, sessionID, true)
 
 	return nil
 }
@@ -587,7 +604,7 @@ func (s *Service) ValidateChannelOp(
 	sessionID int64,
 	channel string,
 ) (int64, error) {
-	chID, err := s.DB.GetChannelByName(ctx, channel)
+	chID, err := s.db.GetChannelByName(ctx, channel)
 	if err != nil {
 		return 0, &IRCError{
 			irc.ErrNoSuchChannel,
@@ -596,7 +613,7 @@ func (s *Service) ValidateChannelOp(
 		}
 	}
 
-	isOp, _ := s.DB.IsChannelOperator(
+	isOp, _ := s.db.IsChannelOperator(
 		ctx, chID, sessionID,
 	)
 	if !isOp {
@@ -619,7 +636,7 @@ func (s *Service) ApplyMemberMode(
 	mode rune,
 	adding bool,
 ) error {
-	targetSID, err := s.DB.GetSessionByNick(
+	targetSID, err := s.db.GetSessionByNick(
 		ctx, targetNick,
 	)
 	if err != nil {
@@ -630,7 +647,7 @@ func (s *Service) ApplyMemberMode(
 		}
 	}
 
-	isMember, _ := s.DB.IsChannelMember(
+	isMember, _ := s.db.IsChannelMember(
 		ctx, chID, targetSID,
 	)
 	if !isMember {
@@ -643,11 +660,11 @@ func (s *Service) ApplyMemberMode(
 
 	switch mode {
 	case 'o':
-		_ = s.DB.SetChannelMemberOperator(
+		_ = s.db.SetChannelMemberOperator(
 			ctx, chID, targetSID, adding,
 		)
 	case 'v':
-		_ = s.DB.SetChannelMemberVoiced(
+		_ = s.db.SetChannelMemberVoiced(
 			ctx, chID, targetSID, adding,
 		)
 	}
@@ -655,7 +672,8 @@ func (s *Service) ApplyMemberMode(
 	return nil
 }
 
-// SetChannelFlag applies +m/-m or +t/-t on a channel.
+// SetChannelFlag applies a simple boolean channel mode
+// (+m/-m, +t/-t, +i/-i, +s/-s, +n/-n).
 func (s *Service) SetChannelFlag(
 	ctx context.Context,
 	chID int64,
@@ -664,29 +682,37 @@ func (s *Service) SetChannelFlag(
 ) error {
 	switch flag {
 	case 'm':
-		if err := s.DB.SetChannelModerated(
+		if err := s.db.SetChannelModerated(
 			ctx, chID, setting,
 		); err != nil {
 			return fmt.Errorf("set moderated: %w", err)
 		}
 	case 't':
-		if err := s.DB.SetChannelTopicLocked(
+		if err := s.db.SetChannelTopicLocked(
 			ctx, chID, setting,
 		); err != nil {
 			return fmt.Errorf("set topic locked: %w", err)
 		}
 	case 'i':
-		if err := s.DB.SetChannelInviteOnly(
+		if err := s.db.SetChannelInviteOnly(
 			ctx, chID, setting,
 		); err != nil {
 			return fmt.Errorf("set invite only: %w", err)
 		}
 	case 's':
-		if err := s.DB.SetChannelSecret(
+		if err := s.db.SetChannelSecret(
 			ctx, chID, setting,
 		); err != nil {
 			return fmt.Errorf("set secret: %w", err)
 		}
+	case 'n':
+		if err := s.db.SetChannelNoExternal(
+			ctx, chID, setting,
+		); err != nil {
+			return fmt.Errorf(
+				"set no external: %w", err,
+			)
+		}
 	}
 
 	return nil
@@ -700,7 +726,7 @@ func (s *Service) BroadcastMode(
 	chID int64,
 	modeText string,
 ) {
-	memberIDs, _ := s.DB.GetChannelMemberIDs(ctx, chID)
+	memberIDs, _ := s.db.GetChannelMemberIDs(ctx, chID)
 	body, _ := json.Marshal([]string{modeText}) //nolint:errchkjson
 
 	_, _, _ = s.FanOut( //nolint:dogsled // fire-and-forget broadcast
@@ -709,24 +735,60 @@ func (s *Service) BroadcastMode(
 	)
 }
 
-// QueryChannelMode returns the channel mode string.
+// QueryChannelMode returns the complete channel mode
+// string including all flags and parameterized modes.
 func (s *Service) QueryChannelMode(
 	ctx context.Context,
 	chID int64,
 ) string {
 	modes := "+"
 
-	moderated, _ := s.DB.IsChannelModerated(ctx, chID)
+	noExternal, _ := s.db.IsChannelNoExternal(ctx, chID)
+	if noExternal {
+		modes += "n"
+	}
+
+	inviteOnly, _ := s.db.IsChannelInviteOnly(ctx, chID)
+	if inviteOnly {
+		modes += "i"
+	}
+
+	moderated, _ := s.db.IsChannelModerated(ctx, chID)
 	if moderated {
 		modes += "m"
 	}
 
-	topicLocked, _ := s.DB.IsChannelTopicLocked(ctx, chID)
+	secret, _ := s.db.IsChannelSecret(ctx, chID)
+	if secret {
+		modes += "s"
+	}
+
+	topicLocked, _ := s.db.IsChannelTopicLocked(ctx, chID)
 	if topicLocked {
 		modes += "t"
 	}
 
-	return modes
+	var modeParams string
+
+	key, _ := s.db.GetChannelKey(ctx, chID)
+	if key != "" {
+		modes += "k"
+		modeParams += " " + key
+	}
+
+	limit, _ := s.db.GetChannelUserLimit(ctx, chID)
+	if limit > 0 {
+		modes += "l"
+		modeParams += " " + strconv.Itoa(limit)
+	}
+
+	bits, _ := s.db.GetChannelHashcashBits(ctx, chID)
+	if bits > 0 {
+		modes += "H"
+		modeParams += " " + strconv.Itoa(bits)
+	}
+
+	return modes + modeParams
 }
 
 // broadcastNickChange notifies channel peers of a nick
@@ -736,7 +798,7 @@ func (s *Service) broadcastNickChange(
 	sessionID int64,
 	oldNick, newNick string,
 ) {
-	channels, err := s.DB.GetSessionChannels(
+	channels, err := s.db.GetSessionChannels(
 		ctx, sessionID,
 	)
 	if err != nil {
@@ -746,7 +808,7 @@ func (s *Service) broadcastNickChange(
 	body, _ := json.Marshal([]string{newNick}) //nolint:errchkjson
 	notified := make(map[int64]bool)
 
-	dbID, _, insErr := s.DB.InsertMessage(
+	dbID, _, insErr := s.db.InsertMessage(
 		ctx, irc.CmdNick, oldNick, "",
 		nil, body, nil,
 	)
@@ -755,12 +817,12 @@ func (s *Service) broadcastNickChange(
 	}
 
 	// Notify the user themselves (for multi-client sync).
-	_ = s.DB.EnqueueToSession(ctx, sessionID, dbID)
+	_ = s.db.EnqueueToSession(ctx, sessionID, dbID)
-	s.Broker.Notify(sessionID)
+	s.broker.Notify(sessionID)
 	notified[sessionID] = true
 
 	for _, ch := range channels {
-		memberIDs, memErr := s.DB.GetChannelMemberIDs(
+		memberIDs, memErr := s.db.GetChannelMemberIDs(
 			ctx, ch.ID,
 		)
 		if memErr != nil {
@@ -774,8 +836,8 @@ func (s *Service) broadcastNickChange(
 
 			notified[mid] = true
 
-			_ = s.DB.EnqueueToSession(ctx, mid, dbID)
+			_ = s.db.EnqueueToSession(ctx, mid, dbID)
-			s.Broker.Notify(mid)
+			s.broker.Notify(mid)
 		}
 	}
 }