fix: default IRC_LISTEN_ADDR to :6667

Add a backward-compatible IRC protocol listener (RFC 1459/2812) that
allows standard IRC clients (irssi, weechat, hexchat, etc.) to connect
directly via TCP.

Key features:
- TCP listener on configurable port (IRC_LISTEN_ADDR env var, e.g. :6667)
- Full IRC wire protocol parsing and formatting
- Connection registration (NICK + USER + optional PASS)
- Channel operations: JOIN, PART, MODE, TOPIC, NAMES, LIST, KICK, INVITE
- Messaging: PRIVMSG, NOTICE (channel and direct)
- Info commands: WHO, WHOIS, LUSERS, MOTD, AWAY
- Operator support: OPER (with configured credentials)
- PING/PONG keepalive
- CAP negotiation (for modern client compatibility)
- Full bridge to HTTP/JSON API (shared DB, broker, sessions)
- Real-time message relay via broker notifications
- Comprehensive test suite (parser + integration tests)

The IRC listener is an optional component — disabled when IRC_LISTEN_ADDR
is empty (the default). The Broker is now an Fx-provided dependency shared
between HTTP handlers and the IRC server.

closes #89

README.md

@@ -27,6 +27,7 @@ web client as a convenience/reference implementation, but the API comes first.
 - [Federation](#federation-server-to-server)
 - [Storage](#storage)
 - [Configuration](#configuration)
+- [IRC Protocol Listener](#irc-protocol-listener)
 - [Deployment](#deployment)
 - [Client Development Guide](#client-development-guide)
 - [Rate Limiting & Abuse Prevention](#rate-limiting--abuse-prevention)
@@ -1079,8 +1080,8 @@ the server to the client (never C2S) and use 3-digit string codes in the
 | `001` | RPL_WELCOME         | After session creation | `{"command":"001","to":"alice","body":["Welcome to the network, alice"]}` |
 | `002` | RPL_YOURHOST        | After session creation | `{"command":"002","to":"alice","body":["Your host is neoirc, running version 0.1"]}` |
 | `003` | RPL_CREATED         | After session creation | `{"command":"003","to":"alice","body":["This server was created 2026-02-10"]}` |
-| `004` | RPL_MYINFO          | After session creation | `{"command":"004","to":"alice","params":["neoirc","0.1","","ikmnostl"]}` |
+| `004` | RPL_MYINFO          | After session creation | `{"command":"004","to":"alice","params":["neoirc","0.1","","mnst"]}` |
-| `005` | RPL_ISUPPORT        | After session creation | `{"command":"005","to":"alice","params":["CHANTYPES=#","NICKLEN=32","PREFIX=(ov)@+","CHANMODES=b,k,Hl,imnst","NETWORK=neoirc"],"body":["are supported by this server"]}` |
+| `005` | RPL_ISUPPORT        | After session creation | `{"command":"005","to":"alice","params":["CHANTYPES=#","NICKLEN=32","PREFIX=(ov)@+","CHANMODES=,,H,mnst","NETWORK=neoirc"],"body":["are supported by this server"]}` |
 | `221` | RPL_UMODEIS         | In response to user MODE query | `{"command":"221","to":"alice","body":["+"]}` |
 | `251` | RPL_LUSERCLIENT     | On connect or LUSERS command | `{"command":"251","to":"alice","body":["There are 5 users and 0 invisible on 1 servers"]}` |
 | `252` | RPL_LUSEROP         | On connect or LUSERS command | `{"command":"252","to":"alice","params":["0"],"body":["operator(s) online"]}` |
@@ -1128,15 +1129,12 @@ Inspired by IRC, simplified:
 
 | Mode | Name           | Meaning | Status |
 |------|----------------|---------|--------|
-| `+b` | Ban            | Prevents matching hostmasks from joining or sending (parameter: `nick!user@host` mask with wildcards) | **Enforced** |
-| `+i` | Invite-only    | Only invited users can join; use `INVITE nick #channel` to invite | **Enforced** |
-| `+k` | Channel key    | Requires a password to join (parameter: key string) | **Enforced** |
-| `+l` | User limit     | Maximum number of members allowed in the channel (parameter: integer) | **Enforced** |
 | `+m` | Moderated      | Only voiced (`+v`) users and operators (`+o`) can send | **Enforced** |
-| `+n` | No external    | Only channel members can send messages to the channel | **Enforced** |
-| `+s` | Secret         | Channel hidden from LIST and WHOIS for non-members | **Enforced** |
 | `+t` | Topic lock     | Only operators can change the topic (default: ON) | **Enforced** |
+| `+n` | No external    | Only channel members can send messages to the channel | **Enforced** |
 | `+H` | Hashcash       | Requires proof-of-work for PRIVMSG (parameter: bits, e.g. `+H 20`) | **Enforced** |
+| `+i` | Invite-only    | Only invited users can join | Not yet enforced |
+| `+s` | Secret         | Channel hidden from LIST response | Not yet enforced |
 
 **User channel modes (set per-user per-channel):**
 
@@ -1148,42 +1146,6 @@ Inspired by IRC, simplified:
 **Channel creator auto-op:** The first user to JOIN a channel (creating it)
 automatically receives `+o` operator status.
 
-**Ban system (+b):** Operators can ban users by hostmask pattern with wildcard
-matching (`*` and `?`). `MODE #channel +b` with no argument lists current bans.
-Bans prevent both joining and sending messages.
-
-```
-MODE #channel +b *!*@*.example.com   — ban all users from example.com
-MODE #channel -b *!*@*.example.com   — remove the ban
-MODE #channel +b                     — list all bans (RPL_BANLIST 367/368)
-```
-
-**Invite-only (+i):** When set, users must be invited by an operator before
-joining. The `INVITE` command records an invite that is consumed on JOIN.
-
-```
-MODE #channel +i                     — set invite-only
-INVITE nick #channel                 — invite a user (operator only on +i channels)
-```
-
-**Channel key (+k):** Requires a password to join the channel.
-
-```
-MODE #channel +k secretpass          — set a channel key
-MODE #channel -k *                   — remove the key
-JOIN #channel secretpass             — join with key
-```
-
-**User limit (+l):** Caps the number of members in the channel.
-
-```
-MODE #channel +l 50                  — set limit to 50 members
-MODE #channel -l                     — remove the limit
-```
-
-**Secret (+s):** Hides the channel from `LIST` for non-members and from
-`WHOIS` channel lists when the querier is not in the same channel.
-
 **KICK command:** Channel operators can remove users with `KICK #channel nick
 [:reason]`. The kicked user and all channel members receive the KICK message.
 
@@ -1192,7 +1154,7 @@ RPL_AWAY), and skips hashcash validation on +H channels (servers and services
 use NOTICE).
 
 **ISUPPORT:** The server advertises `PREFIX=(ov)@+` and
-`CHANMODES=b,k,Hl,imnst` in RPL_ISUPPORT (005).
+`CHANMODES=,,H,mnst` in RPL_ISUPPORT (005).
 
 ### Per-Channel Hashcash (Anti-Spam)
 
@@ -2266,6 +2228,7 @@ directory is also loaded automatically via
 | `NEOIRC_OPER_PASSWORD` | string | `""`                              | Server operator (o-line) password. Both name and password must be set to enable OPER. |
 | `LOGIN_RATE_LIMIT` | float   | `1`                                  | Allowed login attempts per second per IP address. |
 | `LOGIN_RATE_BURST`  | int    | `5`                                  | Maximum burst of login attempts per IP before rate limiting kicks in. |
+| `IRC_LISTEN_ADDR`  | string  | `":6667"`                            | TCP address for the traditional IRC protocol listener. Set empty to disable. |
 | `MAINTENANCE_MODE` | bool    | `false`                              | Maintenance mode flag (reserved) |
 
 ### Example `.env` file
@@ -2282,6 +2245,71 @@ NEOIRC_HASHCASH_BITS=20
 
 ---
 
+## IRC Protocol Listener
+
+neoirc includes an optional traditional IRC wire protocol listener (RFC
+1459/2812) that allows standard IRC clients to connect directly. This enables
+backward compatibility with existing IRC clients like irssi, weechat, hexchat,
+and others.
+
+### Enabling
+
+Set the `IRC_LISTEN_ADDR` environment variable to a TCP address:
+
+```bash
+IRC_LISTEN_ADDR=:6667
+```
+
+When unset or empty, the IRC listener is disabled and only the HTTP/JSON API is
+available.
+
+### Supported Commands
+
+| Category   | Commands                                             |
+|------------|------------------------------------------------------|
+| Connection | `NICK`, `USER`, `PASS`, `QUIT`, `PING`/`PONG`, `CAP` |
+| Channels   | `JOIN`, `PART`, `MODE`, `TOPIC`, `NAMES`, `LIST`, `KICK`, `INVITE` |
+| Messaging  | `PRIVMSG`, `NOTICE`                                  |
+| Info       | `WHO`, `WHOIS`, `LUSERS`, `MOTD`, `AWAY`             |
+| Operator   | `OPER` (requires `NEOIRC_OPER_NAME` and `NEOIRC_OPER_PASSWORD`) |
+
+### Protocol Details
+
+- **Wire format**: CR-LF delimited lines, max 512 bytes per line
+- **Connection registration**: Clients must send `NICK` and `USER` to register.
+  An optional `PASS` before registration sets the session password (minimum 8
+  characters).
+- **CAP negotiation**: `CAP LS` and `CAP END` are silently handled for
+  compatibility with modern clients. No capabilities are advertised.
+- **Channel prefixes**: Channels must start with `#`. If omitted, it's
+  automatically prepended.
+- **First joiner**: The first user to join a channel is automatically granted
+  operator status (`@`).
+- **Channel modes**: `+m` (moderated), `+t` (topic lock), `+o` (operator),
+  `+v` (voice)
+
+### Bridge to HTTP API
+
+Messages sent by IRC clients appear in channels visible to HTTP/JSON API
+clients and vice versa. The IRC listener and HTTP API share the same database,
+broker, and session infrastructure. A user connected via IRC and a user
+connected via the HTTP API can communicate in the same channels seamlessly.
+
+### Docker Usage
+
+To expose the IRC port in Docker:
+
+```bash
+docker run -d \
+  -p 8080:8080 \
+  -p 6667:6667 \
+  -e IRC_LISTEN_ADDR=:6667 \
+  -v neoirc-data:/var/lib/neoirc \
+  neoirc
+```
+
+---
+
 ## Deployment
 
 ### Docker (Recommended)
@@ -2734,7 +2762,7 @@ guess is borne by the server (bcrypt), not the client.
 - [x] **Client output queue pruning** — delete old client output queue entries per `QUEUE_MAX_AGE`
 - [x] **Message rotation** — prune messages older than `MESSAGE_MAX_AGE`
 - [x] **Channel modes** — enforce `+m` (moderated), `+t` (topic lock), `+n` (no external)
-- [x] **Channel modes (tier 2)** — enforce `+i` (invite-only), `+s` (secret), `+b` (ban), `+k` (key), `+l` (limit)
+- [ ] **Channel modes (tier 2)** — enforce `+i` (invite-only), `+s` (secret), `+b` (ban), `+k` (key), `+l` (limit)
 - [x] **User channel modes** — `+o` (operator), `+v` (voice) with NAMES prefixes
 - [x] **KICK command** — operator-only channel kick with broadcast
 - [x] **MODE command** — query and set channel/user modes

cmd/neoircd/main.go

@@ -2,11 +2,13 @@
 package main
 
 import (
+	"git.eeqj.de/sneak/neoirc/internal/broker"
 	"git.eeqj.de/sneak/neoirc/internal/config"
 	"git.eeqj.de/sneak/neoirc/internal/db"
 	"git.eeqj.de/sneak/neoirc/internal/globals"
 	"git.eeqj.de/sneak/neoirc/internal/handlers"
 	"git.eeqj.de/sneak/neoirc/internal/healthcheck"
+	"git.eeqj.de/sneak/neoirc/internal/ircserver"
 	"git.eeqj.de/sneak/neoirc/internal/logger"
 	"git.eeqj.de/sneak/neoirc/internal/middleware"
 	"git.eeqj.de/sneak/neoirc/internal/server"
@@ -28,16 +30,22 @@ func main() {
 
 	fx.New(
 		fx.Provide(
+			broker.New,
 			config.New,
 			db.New,
 			globals.New,
 			handlers.New,
+			ircserver.New,
 			logger.New,
 			server.New,
 			middleware.New,
 			healthcheck.New,
 			stats.New,
 		),
-		fx.Invoke(func(*server.Server) {}),
+		fx.Invoke(func(
+			_ *server.Server,
+			_ *ircserver.Server,
+		) {
+		}),
 	).Run()
 }

internal/config/config.go

@@ -50,6 +50,7 @@ type Config struct {
 	OperPassword       string
 	LoginRateLimit     float64
 	LoginRateBurst     int
+	IRCListenAddr      string
 	params             *Params
 	log                *slog.Logger
 }
@@ -86,6 +87,7 @@ func New(
 	viper.SetDefault("NEOIRC_OPER_PASSWORD", "")
 	viper.SetDefault("LOGIN_RATE_LIMIT", "1")
 	viper.SetDefault("LOGIN_RATE_BURST", "5")
+	viper.SetDefault("IRC_LISTEN_ADDR", ":6667")
 
 	err := viper.ReadInConfig()
 	if err != nil {
@@ -116,6 +118,7 @@ func New(
 		OperPassword:       viper.GetString("NEOIRC_OPER_PASSWORD"),
 		LoginRateLimit:     viper.GetFloat64("LOGIN_RATE_LIMIT"),
 		LoginRateBurst:     viper.GetInt("LOGIN_RATE_BURST"),
+		IRCListenAddr:      viper.GetString("IRC_LISTEN_ADDR"),
 		log:                log,
 		params:             &params,
 	}

internal/db/queries.go

@@ -9,7 +9,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"strconv"
-	"strings"
 	"time"
 
 	"git.eeqj.de/sneak/neoirc/pkg/irc"
@@ -1836,534 +1835,3 @@ func (database *Database) PruneSpentHashcash(
 
 	return deleted, nil
 }
-
-// --- Tier 2: Ban system (+b) ---
-
-// BanInfo represents a channel ban entry.
-type BanInfo struct {
-	Mask      string
-	SetBy     string
-	CreatedAt time.Time
-}
-
-// AddChannelBan inserts a ban mask for a channel.
-func (database *Database) AddChannelBan(
-	ctx context.Context,
-	channelID int64,
-	mask, setBy string,
-) error {
-	_, err := database.conn.ExecContext(ctx,
-		`INSERT OR IGNORE INTO channel_bans
-		 (channel_id, mask, set_by, created_at)
-		 VALUES (?, ?, ?, ?)`,
-		channelID, mask, setBy, time.Now())
-	if err != nil {
-		return fmt.Errorf("add channel ban: %w", err)
-	}
-
-	return nil
-}
-
-// RemoveChannelBan removes a ban mask from a channel.
-func (database *Database) RemoveChannelBan(
-	ctx context.Context,
-	channelID int64,
-	mask string,
-) error {
-	_, err := database.conn.ExecContext(ctx,
-		`DELETE FROM channel_bans
-		 WHERE channel_id = ? AND mask = ?`,
-		channelID, mask)
-	if err != nil {
-		return fmt.Errorf("remove channel ban: %w", err)
-	}
-
-	return nil
-}
-
-// ListChannelBans returns all bans for a channel.
-//
-//nolint:dupl // different query+type vs filtered variant
-func (database *Database) ListChannelBans(
-	ctx context.Context,
-	channelID int64,
-) ([]BanInfo, error) {
-	rows, err := database.conn.QueryContext(ctx,
-		`SELECT mask, set_by, created_at
-		 FROM channel_bans
-		 WHERE channel_id = ?
-		 ORDER BY created_at ASC`,
-		channelID)
-	if err != nil {
-		return nil, fmt.Errorf("list channel bans: %w", err)
-	}
-
-	defer func() { _ = rows.Close() }()
-
-	var bans []BanInfo
-
-	for rows.Next() {
-		var ban BanInfo
-
-		if scanErr := rows.Scan(
-			&ban.Mask, &ban.SetBy, &ban.CreatedAt,
-		); scanErr != nil {
-			return nil, fmt.Errorf(
-				"scan channel ban: %w", scanErr,
-			)
-		}
-
-		bans = append(bans, ban)
-	}
-
-	if rowErr := rows.Err(); rowErr != nil {
-		return nil, fmt.Errorf(
-			"iterate channel bans: %w", rowErr,
-		)
-	}
-
-	return bans, nil
-}
-
-// IsSessionBanned checks if a session's hostmask matches
-// any ban in the channel. Returns true if banned.
-func (database *Database) IsSessionBanned(
-	ctx context.Context,
-	channelID, sessionID int64,
-) (bool, error) {
-	// Get the session's hostmask parts.
-	var nick, username, hostname string
-
-	err := database.conn.QueryRowContext(ctx,
-		`SELECT nick, username, hostname
-		 FROM sessions WHERE id = ?`,
-		sessionID,
-	).Scan(&nick, &username, &hostname)
-	if err != nil {
-		return false, fmt.Errorf(
-			"get session hostmask: %w", err,
-		)
-	}
-
-	hostmask := FormatHostmask(nick, username, hostname)
-
-	// Get all ban masks for the channel.
-	bans, banErr := database.ListChannelBans(ctx, channelID)
-	if banErr != nil {
-		return false, banErr
-	}
-
-	for _, ban := range bans {
-		if MatchBanMask(ban.Mask, hostmask) {
-			return true, nil
-		}
-	}
-
-	return false, nil
-}
-
-// MatchBanMask checks if hostmask matches a ban pattern
-// using IRC-style wildcard matching (* and ?).
-func MatchBanMask(pattern, hostmask string) bool {
-	return wildcardMatch(
-		strings.ToLower(pattern),
-		strings.ToLower(hostmask),
-	)
-}
-
-// wildcardMatch implements simple glob-style matching
-// with * (any sequence) and ? (any single character).
-func wildcardMatch(pattern, str string) bool {
-	for len(pattern) > 0 {
-		switch pattern[0] {
-		case '*':
-			// Skip consecutive asterisks.
-			for len(pattern) > 0 && pattern[0] == '*' {
-				pattern = pattern[1:]
-			}
-
-			if len(pattern) == 0 {
-				return true
-			}
-
-			for i := 0; i <= len(str); i++ {
-				if wildcardMatch(pattern, str[i:]) {
-					return true
-				}
-			}
-
-			return false
-		case '?':
-			if len(str) == 0 {
-				return false
-			}
-
-			pattern = pattern[1:]
-			str = str[1:]
-		default:
-			if len(str) == 0 || pattern[0] != str[0] {
-				return false
-			}
-
-			pattern = pattern[1:]
-			str = str[1:]
-		}
-	}
-
-	return len(str) == 0
-}
-
-// --- Tier 2: Invite-only (+i) ---
-
-// IsChannelInviteOnly checks if a channel has +i mode.
-func (database *Database) IsChannelInviteOnly(
-	ctx context.Context,
-	channelID int64,
-) (bool, error) {
-	var isInviteOnly int
-
-	err := database.conn.QueryRowContext(ctx,
-		`SELECT is_invite_only FROM channels
-		 WHERE id = ?`,
-		channelID,
-	).Scan(&isInviteOnly)
-	if err != nil {
-		return false, fmt.Errorf(
-			"check invite only: %w", err,
-		)
-	}
-
-	return isInviteOnly != 0, nil
-}
-
-// SetChannelInviteOnly sets or unsets +i mode.
-func (database *Database) SetChannelInviteOnly(
-	ctx context.Context,
-	channelID int64,
-	inviteOnly bool,
-) error {
-	val := 0
-	if inviteOnly {
-		val = 1
-	}
-
-	_, err := database.conn.ExecContext(ctx,
-		`UPDATE channels
-		 SET is_invite_only = ?, updated_at = ?
-		 WHERE id = ?`,
-		val, time.Now(), channelID)
-	if err != nil {
-		return fmt.Errorf(
-			"set invite only: %w", err,
-		)
-	}
-
-	return nil
-}
-
-// AddChannelInvite records that a session has been
-// invited to a channel.
-func (database *Database) AddChannelInvite(
-	ctx context.Context,
-	channelID, sessionID int64,
-	invitedBy string,
-) error {
-	_, err := database.conn.ExecContext(ctx,
-		`INSERT OR IGNORE INTO channel_invites
-		 (channel_id, session_id, invited_by, created_at)
-		 VALUES (?, ?, ?, ?)`,
-		channelID, sessionID, invitedBy, time.Now())
-	if err != nil {
-		return fmt.Errorf("add channel invite: %w", err)
-	}
-
-	return nil
-}
-
-// HasChannelInvite checks if a session has been invited
-// to a channel.
-func (database *Database) HasChannelInvite(
-	ctx context.Context,
-	channelID, sessionID int64,
-) (bool, error) {
-	var count int
-
-	err := database.conn.QueryRowContext(ctx,
-		`SELECT COUNT(*) FROM channel_invites
-		 WHERE channel_id = ? AND session_id = ?`,
-		channelID, sessionID,
-	).Scan(&count)
-	if err != nil {
-		return false, fmt.Errorf(
-			"check invite: %w", err,
-		)
-	}
-
-	return count > 0, nil
-}
-
-// ClearChannelInvite removes a session's invite to a
-// channel (called after successful JOIN).
-func (database *Database) ClearChannelInvite(
-	ctx context.Context,
-	channelID, sessionID int64,
-) error {
-	_, err := database.conn.ExecContext(ctx,
-		`DELETE FROM channel_invites
-		 WHERE channel_id = ? AND session_id = ?`,
-		channelID, sessionID)
-	if err != nil {
-		return fmt.Errorf("clear invite: %w", err)
-	}
-
-	return nil
-}
-
-// --- Tier 2: Secret (+s) ---
-
-// IsChannelSecret checks if a channel has +s mode.
-func (database *Database) IsChannelSecret(
-	ctx context.Context,
-	channelID int64,
-) (bool, error) {
-	var isSecret int
-
-	err := database.conn.QueryRowContext(ctx,
-		`SELECT is_secret FROM channels
-		 WHERE id = ?`,
-		channelID,
-	).Scan(&isSecret)
-	if err != nil {
-		return false, fmt.Errorf(
-			"check secret: %w", err,
-		)
-	}
-
-	return isSecret != 0, nil
-}
-
-// SetChannelSecret sets or unsets +s mode.
-func (database *Database) SetChannelSecret(
-	ctx context.Context,
-	channelID int64,
-	secret bool,
-) error {
-	val := 0
-	if secret {
-		val = 1
-	}
-
-	_, err := database.conn.ExecContext(ctx,
-		`UPDATE channels
-		 SET is_secret = ?, updated_at = ?
-		 WHERE id = ?`,
-		val, time.Now(), channelID)
-	if err != nil {
-		return fmt.Errorf("set secret: %w", err)
-	}
-
-	return nil
-}
-
-// ListAllChannelsWithCountsFiltered returns all channels
-// with member counts, excluding secret channels that
-// the given session is not a member of.
-//
-//nolint:dupl // different query+type vs ListChannelBans
-func (database *Database) ListAllChannelsWithCountsFiltered(
-	ctx context.Context,
-	sessionID int64,
-) ([]ChannelInfoFull, error) {
-	rows, err := database.conn.QueryContext(ctx,
-		`SELECT c.name, COUNT(cm.id) AS member_count,
-		        c.topic
-		 FROM channels c
-		 LEFT JOIN channel_members cm
-		   ON cm.channel_id = c.id
-		 WHERE c.is_secret = 0
-		    OR c.id IN (
-		       SELECT channel_id FROM channel_members
-		       WHERE session_id = ?
-		    )
-		 GROUP BY c.id
-		 ORDER BY c.name ASC`,
-		sessionID)
-	if err != nil {
-		return nil, fmt.Errorf(
-			"list channels filtered: %w", err,
-		)
-	}
-
-	defer func() { _ = rows.Close() }()
-
-	var channels []ChannelInfoFull
-
-	for rows.Next() {
-		var chanInfo ChannelInfoFull
-
-		if scanErr := rows.Scan(
-			&chanInfo.Name,
-			&chanInfo.MemberCount,
-			&chanInfo.Topic,
-		); scanErr != nil {
-			return nil, fmt.Errorf(
-				"scan channel: %w", scanErr,
-			)
-		}
-
-		channels = append(channels, chanInfo)
-	}
-
-	if rowErr := rows.Err(); rowErr != nil {
-		return nil, fmt.Errorf(
-			"iterate channels: %w", rowErr,
-		)
-	}
-
-	return channels, nil
-}
-
-// GetSessionChannelsFiltered returns channels a session
-// belongs to, optionally excluding secret channels for
-// WHOIS (when the querier is not in the same channel).
-// If querierID == targetID, returns all channels.
-func (database *Database) GetSessionChannelsFiltered(
-	ctx context.Context,
-	targetSID, querierSID int64,
-) ([]ChannelInfo, error) {
-	// If querying yourself, return all channels.
-	if targetSID == querierSID {
-		return database.GetSessionChannels(ctx, targetSID)
-	}
-
-	rows, err := database.conn.QueryContext(ctx,
-		`SELECT c.id, c.name, c.topic
-		 FROM channels c
-		 JOIN channel_members cm
-		   ON cm.channel_id = c.id
-		 WHERE cm.session_id = ?
-		   AND (c.is_secret = 0
-		        OR c.id IN (
-		           SELECT channel_id FROM channel_members
-		           WHERE session_id = ?
-		        ))
-		 ORDER BY c.name ASC`,
-		targetSID, querierSID)
-	if err != nil {
-		return nil, fmt.Errorf(
-			"get session channels filtered: %w", err,
-		)
-	}
-
-	defer func() { _ = rows.Close() }()
-
-	var channels []ChannelInfo
-
-	for rows.Next() {
-		var chanInfo ChannelInfo
-
-		if scanErr := rows.Scan(
-			&chanInfo.ID,
-			&chanInfo.Name,
-			&chanInfo.Topic,
-		); scanErr != nil {
-			return nil, fmt.Errorf(
-				"scan channel: %w", scanErr,
-			)
-		}
-
-		channels = append(channels, chanInfo)
-	}
-
-	if rowErr := rows.Err(); rowErr != nil {
-		return nil, fmt.Errorf(
-			"iterate channels: %w", rowErr,
-		)
-	}
-
-	return channels, nil
-}
-
-// --- Tier 2: Channel Key (+k) ---
-
-// GetChannelKey returns the key for a channel (empty
-// string means no key set).
-func (database *Database) GetChannelKey(
-	ctx context.Context,
-	channelID int64,
-) (string, error) {
-	var key string
-
-	err := database.conn.QueryRowContext(ctx,
-		`SELECT channel_key FROM channels
-		 WHERE id = ?`,
-		channelID,
-	).Scan(&key)
-	if err != nil {
-		return "", fmt.Errorf("get channel key: %w", err)
-	}
-
-	return key, nil
-}
-
-// SetChannelKey sets or clears the key for a channel.
-func (database *Database) SetChannelKey(
-	ctx context.Context,
-	channelID int64,
-	key string,
-) error {
-	_, err := database.conn.ExecContext(ctx,
-		`UPDATE channels
-		 SET channel_key = ?, updated_at = ?
-		 WHERE id = ?`,
-		key, time.Now(), channelID)
-	if err != nil {
-		return fmt.Errorf("set channel key: %w", err)
-	}
-
-	return nil
-}
-
-// --- Tier 2: User Limit (+l) ---
-
-// GetChannelUserLimit returns the user limit for a
-// channel (0 means no limit).
-func (database *Database) GetChannelUserLimit(
-	ctx context.Context,
-	channelID int64,
-) (int, error) {
-	var limit int
-
-	err := database.conn.QueryRowContext(ctx,
-		`SELECT user_limit FROM channels
-		 WHERE id = ?`,
-		channelID,
-	).Scan(&limit)
-	if err != nil {
-		return 0, fmt.Errorf(
-			"get channel user limit: %w", err,
-		)
-	}
-
-	return limit, nil
-}
-
-// SetChannelUserLimit sets the user limit for a channel.
-func (database *Database) SetChannelUserLimit(
-	ctx context.Context,
-	channelID int64,
-	limit int,
-) error {
-	_, err := database.conn.ExecContext(ctx,
-		`UPDATE channels
-		 SET user_limit = ?, updated_at = ?
-		 WHERE id = ?`,
-		limit, time.Now(), channelID)
-	if err != nil {
-		return fmt.Errorf(
-			"set channel user limit: %w", err,
-		)
-	}
-
-	return nil
-}

internal/db/queries_test.go

@@ -1017,474 +1017,3 @@ func TestGetOperCount(t *testing.T) {
 		t.Fatalf("expected 1 oper, got %d", count)
 	}
 }
-
-// --- Tier 2 Tests ---
-
-func TestWildcardMatch(t *testing.T) {
-	t.Parallel()
-
-	tests := []struct {
-		pattern string
-		input   string
-		match   bool
-	}{
-		{"*!*@*", "nick!user@host", true},
-		{"*!*@*.example.com", "nick!user@foo.example.com", true},
-		{"*!*@*.example.com", "nick!user@other.net", false},
-		{"badnick!*@*", "badnick!user@host", true},
-		{"badnick!*@*", "goodnick!user@host", false},
-		{"nick!user@host", "nick!user@host", true},
-		{"nick!user@host", "nick!user@other", false},
-		{"*", "anything", true},
-		{"?ick!*@*", "nick!user@host", true},
-		{"?ick!*@*", "nn!user@host", false},
-		// Case-insensitive.
-		{"Nick!*@*", "nick!user@host", true},
-	}
-
-	for _, tc := range tests {
-		result := db.MatchBanMask(tc.pattern, tc.input)
-		if result != tc.match {
-			t.Errorf(
-				"MatchBanMask(%q, %q) = %v, want %v",
-				tc.pattern, tc.input, result, tc.match,
-			)
-		}
-	}
-}
-
-func TestChannelBanCRUD(t *testing.T) {
-	t.Parallel()
-
-	database := setupTestDB(t)
-	ctx := t.Context()
-
-	chID, err := database.GetOrCreateChannel(ctx, "#test")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// No bans initially.
-	bans, err := database.ListChannelBans(ctx, chID)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if len(bans) != 0 {
-		t.Fatalf("expected 0 bans, got %d", len(bans))
-	}
-
-	// Add a ban.
-	err = database.AddChannelBan(
-		ctx, chID, "*!*@evil.com", "op",
-	)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	bans, err = database.ListChannelBans(ctx, chID)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if len(bans) != 1 {
-		t.Fatalf("expected 1 ban, got %d", len(bans))
-	}
-
-	if bans[0].Mask != "*!*@evil.com" {
-		t.Fatalf("wrong mask: %s", bans[0].Mask)
-	}
-
-	// Duplicate add is ignored (OR IGNORE).
-	err = database.AddChannelBan(
-		ctx, chID, "*!*@evil.com", "op2",
-	)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	bans, _ = database.ListChannelBans(ctx, chID)
-	if len(bans) != 1 {
-		t.Fatalf("expected 1 ban after dup, got %d", len(bans))
-	}
-
-	// Remove ban.
-	err = database.RemoveChannelBan(
-		ctx, chID, "*!*@evil.com",
-	)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	bans, _ = database.ListChannelBans(ctx, chID)
-	if len(bans) != 0 {
-		t.Fatalf("expected 0 bans after remove, got %d", len(bans))
-	}
-}
-
-func TestIsSessionBanned(t *testing.T) {
-	t.Parallel()
-
-	database := setupTestDB(t)
-	ctx := t.Context()
-
-	sid, _, _, err := database.CreateSession(
-		ctx, "victim", "victim", "evil.com", "",
-	)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	chID, err := database.GetOrCreateChannel(ctx, "#bantest")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Not banned initially.
-	banned, err := database.IsSessionBanned(ctx, chID, sid)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if banned {
-		t.Fatal("should not be banned initially")
-	}
-
-	// Add ban matching the hostmask.
-	err = database.AddChannelBan(
-		ctx, chID, "*!*@evil.com", "op",
-	)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	banned, err = database.IsSessionBanned(ctx, chID, sid)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if !banned {
-		t.Fatal("should be banned")
-	}
-}
-
-func TestChannelInviteOnly(t *testing.T) {
-	t.Parallel()
-
-	database := setupTestDB(t)
-	ctx := t.Context()
-
-	chID, err := database.GetOrCreateChannel(ctx, "#invite")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Default: not invite-only.
-	isIO, err := database.IsChannelInviteOnly(ctx, chID)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if isIO {
-		t.Fatal("should not be invite-only by default")
-	}
-
-	// Set invite-only.
-	err = database.SetChannelInviteOnly(ctx, chID, true)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	isIO, _ = database.IsChannelInviteOnly(ctx, chID)
-	if !isIO {
-		t.Fatal("should be invite-only")
-	}
-
-	// Unset.
-	err = database.SetChannelInviteOnly(ctx, chID, false)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	isIO, _ = database.IsChannelInviteOnly(ctx, chID)
-	if isIO {
-		t.Fatal("should not be invite-only")
-	}
-}
-
-func TestChannelInviteCRUD(t *testing.T) {
-	t.Parallel()
-
-	database := setupTestDB(t)
-	ctx := t.Context()
-
-	sid, _, _, err := database.CreateSession(
-		ctx, "invited", "", "", "",
-	)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	chID, err := database.GetOrCreateChannel(ctx, "#inv")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// No invite initially.
-	has, err := database.HasChannelInvite(ctx, chID, sid)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if has {
-		t.Fatal("should not have invite")
-	}
-
-	// Add invite.
-	err = database.AddChannelInvite(ctx, chID, sid, "op")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	has, _ = database.HasChannelInvite(ctx, chID, sid)
-	if !has {
-		t.Fatal("should have invite")
-	}
-
-	// Clear invite.
-	err = database.ClearChannelInvite(ctx, chID, sid)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	has, _ = database.HasChannelInvite(ctx, chID, sid)
-	if has {
-		t.Fatal("invite should be cleared")
-	}
-}
-
-func TestChannelSecret(t *testing.T) {
-	t.Parallel()
-
-	database := setupTestDB(t)
-	ctx := t.Context()
-
-	chID, err := database.GetOrCreateChannel(ctx, "#secret")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Default: not secret.
-	isSec, err := database.IsChannelSecret(ctx, chID)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if isSec {
-		t.Fatal("should not be secret by default")
-	}
-
-	err = database.SetChannelSecret(ctx, chID, true)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	isSec, _ = database.IsChannelSecret(ctx, chID)
-	if !isSec {
-		t.Fatal("should be secret")
-	}
-}
-
-// createTestSession is a helper to create a session and
-// return only the session ID.
-func createTestSession(
-	t *testing.T,
-	database *db.Database,
-	nick string,
-) int64 {
-	t.Helper()
-
-	sid, _, _, err := database.CreateSession(
-		t.Context(), nick, "", "", "",
-	)
-	if err != nil {
-		t.Fatalf("create session %s: %v", nick, err)
-	}
-
-	return sid
-}
-
-func TestSecretChannelFiltering(t *testing.T) {
-	t.Parallel()
-
-	database := setupTestDB(t)
-	ctx := t.Context()
-
-	// Create two sessions.
-	sid1 := createTestSession(t, database, "member")
-	sid2 := createTestSession(t, database, "outsider")
-
-	// Create a secret channel.
-	chID, _ := database.GetOrCreateChannel(ctx, "#secret")
-	_ = database.SetChannelSecret(ctx, chID, true)
-	_ = database.JoinChannel(ctx, chID, sid1)
-
-	// Create a non-secret channel.
-	chID2, _ := database.GetOrCreateChannel(ctx, "#public")
-	_ = database.JoinChannel(ctx, chID2, sid1)
-
-	// Member should see both.
-	list, err := database.ListAllChannelsWithCountsFiltered(
-		ctx, sid1,
-	)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if len(list) != 2 {
-		t.Fatalf("member should see 2 channels, got %d", len(list))
-	}
-
-	// Outsider should only see public.
-	list, _ = database.ListAllChannelsWithCountsFiltered(
-		ctx, sid2,
-	)
-	if len(list) != 1 {
-		t.Fatalf("outsider should see 1 channel, got %d", len(list))
-	}
-
-	if list[0].Name != "#public" {
-		t.Fatalf("outsider should see #public, got %s", list[0].Name)
-	}
-}
-
-func TestWhoisChannelFiltering(t *testing.T) {
-	t.Parallel()
-
-	database := setupTestDB(t)
-	ctx := t.Context()
-
-	sid1 := createTestSession(t, database, "target")
-	sid2 := createTestSession(t, database, "querier")
-
-	// Create secret channel, target joins it.
-	chID, _ := database.GetOrCreateChannel(ctx, "#hidden")
-	_ = database.SetChannelSecret(ctx, chID, true)
-	_ = database.JoinChannel(ctx, chID, sid1)
-
-	// Querier (non-member) should not see the channel.
-	channels, err := database.GetSessionChannelsFiltered(
-		ctx, sid1, sid2,
-	)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if len(channels) != 0 {
-		t.Fatalf(
-			"querier should see 0 channels, got %d",
-			len(channels),
-		)
-	}
-
-	// Target querying self should see it.
-	channels, _ = database.GetSessionChannelsFiltered(
-		ctx, sid1, sid1,
-	)
-	if len(channels) != 1 {
-		t.Fatalf(
-			"self-query should see 1 channel, got %d",
-			len(channels),
-		)
-	}
-}
-
-//nolint:dupl // structurally similar to TestChannelUserLimit
-func TestChannelKey(t *testing.T) {
-	t.Parallel()
-
-	database := setupTestDB(t)
-	ctx := t.Context()
-
-	chID, err := database.GetOrCreateChannel(ctx, "#keyed")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Default: no key.
-	key, err := database.GetChannelKey(ctx, chID)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if key != "" {
-		t.Fatalf("expected empty key, got %q", key)
-	}
-
-	// Set key.
-	err = database.SetChannelKey(ctx, chID, "secret123")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	key, _ = database.GetChannelKey(ctx, chID)
-	if key != "secret123" {
-		t.Fatalf("expected secret123, got %q", key)
-	}
-
-	// Clear key.
-	err = database.SetChannelKey(ctx, chID, "")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	key, _ = database.GetChannelKey(ctx, chID)
-	if key != "" {
-		t.Fatalf("expected empty key, got %q", key)
-	}
-}
-
-//nolint:dupl // structurally similar to TestChannelKey
-func TestChannelUserLimit(t *testing.T) {
-	t.Parallel()
-
-	database := setupTestDB(t)
-	ctx := t.Context()
-
-	chID, err := database.GetOrCreateChannel(ctx, "#limited")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Default: no limit.
-	limit, err := database.GetChannelUserLimit(ctx, chID)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if limit != 0 {
-		t.Fatalf("expected 0 limit, got %d", limit)
-	}
-
-	// Set limit.
-	err = database.SetChannelUserLimit(ctx, chID, 50)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	limit, _ = database.GetChannelUserLimit(ctx, chID)
-	if limit != 50 {
-		t.Fatalf("expected 50, got %d", limit)
-	}
-
-	// Clear limit.
-	err = database.SetChannelUserLimit(ctx, chID, 0)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	limit, _ = database.GetChannelUserLimit(ctx, chID)
-	if limit != 0 {
-		t.Fatalf("expected 0, got %d", limit)
-	}
-}

internal/db/schema/001_initial.sql

@@ -42,36 +42,10 @@ CREATE TABLE IF NOT EXISTS channels (
     hashcash_bits INTEGER NOT NULL DEFAULT 0,
     is_moderated INTEGER NOT NULL DEFAULT 0,
     is_topic_locked INTEGER NOT NULL DEFAULT 1,
-    is_invite_only INTEGER NOT NULL DEFAULT 0,
-    is_secret INTEGER NOT NULL DEFAULT 0,
-    channel_key TEXT NOT NULL DEFAULT '',
-    user_limit INTEGER NOT NULL DEFAULT 0,
     created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
     updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
 );
 
--- Channel bans
-CREATE TABLE IF NOT EXISTS channel_bans (
-    id INTEGER PRIMARY KEY AUTOINCREMENT,
-    channel_id INTEGER NOT NULL REFERENCES channels(id) ON DELETE CASCADE,
-    mask TEXT NOT NULL,
-    set_by TEXT NOT NULL,
-    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
-    UNIQUE(channel_id, mask)
-);
-CREATE INDEX IF NOT EXISTS idx_channel_bans_channel ON channel_bans(channel_id);
-
--- Channel invites (in-memory would be simpler but DB survives restarts)
-CREATE TABLE IF NOT EXISTS channel_invites (
-    id INTEGER PRIMARY KEY AUTOINCREMENT,
-    channel_id INTEGER NOT NULL REFERENCES channels(id) ON DELETE CASCADE,
-    session_id INTEGER NOT NULL REFERENCES sessions(id) ON DELETE CASCADE,
-    invited_by TEXT NOT NULL DEFAULT '',
-    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
-    UNIQUE(channel_id, session_id)
-);
-CREATE INDEX IF NOT EXISTS idx_channel_invites_channel ON channel_invites(channel_id);
-
 -- Channel members
 CREATE TABLE IF NOT EXISTS channel_members (
     id INTEGER PRIMARY KEY AUTOINCREMENT,

internal/db/testing.go

@@ -0,0 +1,25 @@
+package db
+
+import (
+	"context"
+	"database/sql"
+	"log/slog"
+)
+
+// NewTestDatabaseFromConn creates a Database wrapping an
+// existing *sql.DB connection.  Intended for integration
+// tests in other packages.
+func NewTestDatabaseFromConn(conn *sql.DB) *Database {
+	return &Database{ //nolint:exhaustruct
+		conn: conn,
+		log:  slog.Default(),
+	}
+}
+
+// RunMigrations applies all schema migrations.  Exposed
+// for integration tests in other packages.
+func (database *Database) RunMigrations(
+	ctx context.Context,
+) error {
+	return database.runMigrations(ctx)
+}

internal/handlers/api_test.go

@@ -18,6 +18,7 @@ import (
 	"testing"
 	"time"
 
+	"git.eeqj.de/sneak/neoirc/internal/broker"
 	"git.eeqj.de/sneak/neoirc/internal/config"
 	"git.eeqj.de/sneak/neoirc/internal/db"
 	"git.eeqj.de/sneak/neoirc/internal/globals"
@@ -213,6 +214,7 @@ func newTestHandlers(
 		Database:    database,
 		Healthcheck: hcheck,
 		Stats:       tracker,
+		Broker:      broker.New(),
 	})
 	if err != nil {
 		return nil, fmt.Errorf("test handlers: %w", err)
@@ -4378,486 +4380,3 @@ func TestKickDefaultReason(t *testing.T) {
 		)
 	}
 }
-
-// --- Tier 2 Handler Tests ---
-
-const (
-	inviteCmd    = "INVITE"
-	joinedStatus = "joined"
-)
-
-// TestBanAddRemoveList verifies +b add, list, and -b
-// remove via MODE commands.
-func TestBanAddRemoveList(t *testing.T) {
-	tserver := newTestServer(t)
-	opToken := tserver.createSession("banop")
-
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: joinCmd, toKey: "#bans",
-	})
-
-	// Add a ban.
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: modeCmd,
-		toKey:      "#bans",
-		bodyKey:    []string{"+b", "*!*@evil.com"},
-	})
-
-	_, lastID := tserver.pollMessages(opToken, 0)
-
-	// List bans (+b with no argument).
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: modeCmd,
-		toKey:      "#bans",
-		bodyKey:    []string{"+b"},
-	})
-
-	msgs, _ := tserver.pollMessages(opToken, lastID)
-
-	// Should have RPL_BANLIST (367).
-	banMsg := findNumericWithParams(msgs, "367")
-	if banMsg == nil {
-		t.Fatalf("expected 367 RPL_BANLIST, got %v", msgs)
-	}
-
-	// Should have RPL_ENDOFBANLIST (368).
-	if !findNumeric(msgs, "368") {
-		t.Fatal("expected 368 RPL_ENDOFBANLIST")
-	}
-
-	// Remove the ban.
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: modeCmd,
-		toKey:      "#bans",
-		bodyKey:    []string{"-b", "*!*@evil.com"},
-	})
-
-	_, lastID = tserver.pollMessages(opToken, lastID)
-
-	// List again — should be empty (just end-of-list).
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: modeCmd,
-		toKey:      "#bans",
-		bodyKey:    []string{"+b"},
-	})
-
-	msgs, _ = tserver.pollMessages(opToken, lastID)
-	banMsg = findNumericWithParams(msgs, "367")
-	if banMsg != nil {
-		t.Fatal("expected no 367 after ban removal")
-	}
-
-	if !findNumeric(msgs, "368") {
-		t.Fatal("expected 368 RPL_ENDOFBANLIST")
-	}
-}
-
-// TestBanBlocksJoin verifies that a banned user cannot
-// join a channel.
-func TestBanBlocksJoin(t *testing.T) {
-	tserver := newTestServer(t)
-	opToken := tserver.createSession("banop2")
-	userToken := tserver.createSession("banned2")
-
-	// Op creates channel and sets a ban.
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: joinCmd, toKey: "#banjoin",
-	})
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: modeCmd,
-		toKey:      "#banjoin",
-		bodyKey:    []string{"+b", "banned2!*@*"},
-	})
-
-	// Banned user tries to join.
-	_, lastID := tserver.pollMessages(userToken, 0)
-	tserver.sendCommand(userToken, map[string]any{
-		commandKey: joinCmd, toKey: "#banjoin",
-	})
-
-	msgs, _ := tserver.pollMessages(userToken, lastID)
-
-	// Should get ERR_BANNEDFROMCHAN (474).
-	if !findNumeric(msgs, "474") {
-		t.Fatalf("expected 474 ERR_BANNEDFROMCHAN, got %v", msgs)
-	}
-}
-
-// TestBanBlocksPrivmsg verifies that a banned user who
-// is already in a channel cannot send messages.
-func TestBanBlocksPrivmsg(t *testing.T) {
-	tserver := newTestServer(t)
-	opToken := tserver.createSession("banmsgop")
-	userToken := tserver.createSession("banmsgusr")
-
-	// Both join.
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: joinCmd, toKey: "#banmsg",
-	})
-	tserver.sendCommand(userToken, map[string]any{
-		commandKey: joinCmd, toKey: "#banmsg",
-	})
-
-	// Op bans the user.
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: modeCmd,
-		toKey:      "#banmsg",
-		bodyKey:    []string{"+b", "banmsgusr!*@*"},
-	})
-
-	// User tries to send a message.
-	_, lastID := tserver.pollMessages(userToken, 0)
-	tserver.sendCommand(userToken, map[string]any{
-		commandKey: privmsgCmd,
-		toKey:      "#banmsg",
-		bodyKey:    []string{"hello"},
-	})
-
-	msgs, _ := tserver.pollMessages(userToken, lastID)
-
-	// Should get ERR_CANNOTSENDTOCHAN (404).
-	if !findNumeric(msgs, "404") {
-		t.Fatalf("expected 404 ERR_CANNOTSENDTOCHAN, got %v", msgs)
-	}
-}
-
-// TestInviteOnlyJoin verifies +i behavior: join rejected
-// without invite, accepted with invite.
-func TestInviteOnlyJoin(t *testing.T) {
-	tserver := newTestServer(t)
-	opToken := tserver.createSession("invop")
-	userToken := tserver.createSession("invusr")
-
-	// Op creates channel and sets +i.
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: joinCmd, toKey: "#invonly",
-	})
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: modeCmd,
-		toKey:      "#invonly",
-		bodyKey:    []string{"+i"},
-	})
-
-	// User tries to join without invite.
-	_, lastID := tserver.pollMessages(userToken, 0)
-	tserver.sendCommand(userToken, map[string]any{
-		commandKey: joinCmd, toKey: "#invonly",
-	})
-
-	msgs, _ := tserver.pollMessages(userToken, lastID)
-
-	if !findNumeric(msgs, "473") {
-		t.Fatalf(
-			"expected 473 ERR_INVITEONLYCHAN, got %v",
-			msgs,
-		)
-	}
-
-	// Op invites user.
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: inviteCmd,
-		bodyKey:    []string{"invusr", "#invonly"},
-	})
-
-	// User tries again — should succeed with invite.
-	_, result := tserver.sendCommand(userToken, map[string]any{
-		commandKey: joinCmd, toKey: "#invonly",
-	})
-
-	if result[statusKey] != joinedStatus {
-		t.Fatalf(
-			"expected join to succeed with invite, got %v",
-			result,
-		)
-	}
-}
-
-// TestSecretChannelHiddenFromList verifies +s hides a
-// channel from LIST for non-members.
-func TestSecretChannelHiddenFromList(t *testing.T) {
-	tserver := newTestServer(t)
-	opToken := tserver.createSession("secop")
-	outsiderToken := tserver.createSession("secout")
-
-	// Op creates secret channel.
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: joinCmd, toKey: "#secret",
-	})
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: modeCmd,
-		toKey:      "#secret",
-		bodyKey:    []string{"+s"},
-	})
-
-	// Outsider does LIST.
-	_, lastID := tserver.pollMessages(outsiderToken, 0)
-	tserver.sendCommand(outsiderToken, map[string]any{
-		commandKey: "LIST",
-	})
-
-	msgs, _ := tserver.pollMessages(outsiderToken, lastID)
-
-	// Should NOT see #secret in any 322 (RPL_LIST).
-	for _, msg := range msgs {
-		code, ok := msg["code"].(float64)
-		if !ok || int(code) != 322 {
-			continue
-		}
-
-		params := getNumericParams(msg)
-		for _, p := range params {
-			if p == "#secret" {
-				t.Fatal("outsider should not see #secret in LIST")
-			}
-		}
-	}
-
-	// Member does LIST — should see it.
-	_, lastID = tserver.pollMessages(opToken, 0)
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: "LIST",
-	})
-
-	msgs, _ = tserver.pollMessages(opToken, lastID)
-
-	found := false
-
-	for _, msg := range msgs {
-		code, ok := msg["code"].(float64)
-		if !ok || int(code) != 322 {
-			continue
-		}
-
-		params := getNumericParams(msg)
-		for _, p := range params {
-			if p == "#secret" {
-				found = true
-			}
-		}
-	}
-
-	if !found {
-		t.Fatal("member should see #secret in LIST")
-	}
-}
-
-// TestChannelKeyJoin verifies +k behavior: wrong/missing
-// key is rejected, correct key allows join.
-func TestChannelKeyJoin(t *testing.T) {
-	tserver := newTestServer(t)
-	opToken := tserver.createSession("keyop")
-	userToken := tserver.createSession("keyusr")
-
-	// Op creates keyed channel.
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: joinCmd, toKey: "#keyed",
-	})
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: modeCmd,
-		toKey:      "#keyed",
-		bodyKey:    []string{"+k", "mykey"},
-	})
-
-	// User tries without key.
-	_, lastID := tserver.pollMessages(userToken, 0)
-	tserver.sendCommand(userToken, map[string]any{
-		commandKey: joinCmd, toKey: "#keyed",
-	})
-
-	msgs, _ := tserver.pollMessages(userToken, lastID)
-
-	if !findNumeric(msgs, "475") {
-		t.Fatalf(
-			"expected 475 ERR_BADCHANNELKEY, got %v",
-			msgs,
-		)
-	}
-
-	// User tries with wrong key.
-	tserver.sendCommand(userToken, map[string]any{
-		commandKey: joinCmd,
-		toKey:      "#keyed",
-		bodyKey:    []string{"wrongkey"},
-	})
-
-	msgs, _ = tserver.pollMessages(userToken, lastID)
-	if !findNumeric(msgs, "475") {
-		t.Fatalf(
-			"expected 475 ERR_BADCHANNELKEY for wrong key, got %v",
-			msgs,
-		)
-	}
-
-	// User tries with correct key.
-	_, result := tserver.sendCommand(userToken, map[string]any{
-		commandKey: joinCmd,
-		toKey:      "#keyed",
-		bodyKey:    []string{"mykey"},
-	})
-
-	if result[statusKey] != joinedStatus {
-		t.Fatalf(
-			"expected join to succeed with correct key, got %v",
-			result,
-		)
-	}
-}
-
-// TestUserLimitEnforcement verifies +l behavior: blocks
-// join when at capacity.
-func TestUserLimitEnforcement(t *testing.T) {
-	tserver := newTestServer(t)
-	opToken := tserver.createSession("limop")
-	user1Token := tserver.createSession("limusr1")
-	user2Token := tserver.createSession("limusr2")
-
-	// Op creates channel with limit 2.
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: joinCmd, toKey: "#limited",
-	})
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: modeCmd,
-		toKey:      "#limited",
-		bodyKey:    []string{"+l", "2"},
-	})
-
-	// User1 joins — should succeed (2 members now: op + user1).
-	_, result := tserver.sendCommand(user1Token, map[string]any{
-		commandKey: joinCmd, toKey: "#limited",
-	})
-	if result[statusKey] != joinedStatus {
-		t.Fatalf("user1 should join, got %v", result)
-	}
-
-	// User2 tries to join — should fail (at limit: 2/2).
-	_, lastID := tserver.pollMessages(user2Token, 0)
-	tserver.sendCommand(user2Token, map[string]any{
-		commandKey: joinCmd, toKey: "#limited",
-	})
-
-	msgs, _ := tserver.pollMessages(user2Token, lastID)
-
-	if !findNumeric(msgs, "471") {
-		t.Fatalf(
-			"expected 471 ERR_CHANNELISFULL, got %v",
-			msgs,
-		)
-	}
-}
-
-// TestModeStringIncludesNewModes verifies that querying
-// channel mode returns the new modes (+i, +s, +k, +l).
-func TestModeStringIncludesNewModes(t *testing.T) {
-	tserver := newTestServer(t)
-	opToken := tserver.createSession("modestrop")
-
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: joinCmd, toKey: "#modestr",
-	})
-
-	// Set all tier 2 modes.
-	for _, modeChange := range [][]string{
-		{"+i"}, {"+s"}, {"+k", "pw"}, {"+l", "50"},
-	} {
-		tserver.sendCommand(opToken, map[string]any{
-			commandKey: modeCmd,
-			toKey:      "#modestr",
-			bodyKey:    modeChange,
-		})
-	}
-
-	_, lastID := tserver.pollMessages(opToken, 0)
-
-	// Query mode.
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: modeCmd, toKey: "#modestr",
-	})
-
-	msgs, _ := tserver.pollMessages(opToken, lastID)
-	modeMsg := findNumericWithParams(msgs, "324")
-
-	if modeMsg == nil {
-		t.Fatal("expected 324 RPL_CHANNELMODEIS")
-	}
-
-	params := getNumericParams(modeMsg)
-	if len(params) < 2 {
-		t.Fatalf("too few params in 324: %v", params)
-	}
-
-	modeString := params[1]
-
-	for _, c := range []string{"i", "s", "k", "l"} {
-		if !strings.Contains(modeString, c) {
-			t.Fatalf(
-				"mode string %q missing %q",
-				modeString, c,
-			)
-		}
-	}
-}
-
-// TestISUPPORT verifies the 005 numeric includes the
-// updated CHANMODES string.
-func TestISUPPORT(t *testing.T) {
-	tserver := newTestServer(t)
-	token := tserver.createSession("isupport")
-
-	msgs, _ := tserver.pollMessages(token, 0)
-
-	isupp := findNumericWithParams(msgs, "005")
-	if isupp == nil {
-		t.Fatal("expected 005 RPL_ISUPPORT")
-	}
-
-	body, _ := isupp["body"].(string)
-	params := getNumericParams(isupp)
-
-	combined := body + " " + strings.Join(params, " ")
-
-	if !strings.Contains(combined, "CHANMODES=b,k,Hl,imnst") {
-		t.Fatalf(
-			"ISUPPORT missing updated CHANMODES, got body=%q params=%v",
-			body, params,
-		)
-	}
-}
-
-// TestNonOpCannotSetModes verifies non-operators
-// cannot set +i, +s, +k, +l, +b.
-func TestNonOpCannotSetModes(t *testing.T) {
-	tserver := newTestServer(t)
-	opToken := tserver.createSession("modeopx")
-	userToken := tserver.createSession("modeusrx")
-
-	tserver.sendCommand(opToken, map[string]any{
-		commandKey: joinCmd, toKey: "#noperm",
-	})
-	tserver.sendCommand(userToken, map[string]any{
-		commandKey: joinCmd, toKey: "#noperm",
-	})
-
-	modes := [][]string{
-		{"+i"}, {"+s"}, {"+k", "key"}, {"+l", "10"},
-		{"+b", "bad!*@*"},
-	}
-
-	for _, modeChange := range modes {
-		_, lastID := tserver.pollMessages(userToken, 0)
-		tserver.sendCommand(userToken, map[string]any{
-			commandKey: modeCmd,
-			toKey:      "#noperm",
-			bodyKey:    modeChange,
-		})
-
-		msgs, _ := tserver.pollMessages(userToken, lastID)
-
-		// Should get 482 ERR_CHANOPRIVSNEEDED.
-		if !findNumeric(msgs, "482") {
-			t.Fatalf(
-				"expected 482 for %v, got %v",
-				modeChange, msgs,
-			)
-		}
-	}
-}

internal/handlers/handlers.go

@@ -33,6 +33,7 @@ type Params struct {
 	Database    *db.Database
 	Healthcheck *healthcheck.Healthcheck
 	Stats       *stats.Tracker
+	Broker      *broker.Broker
 }
 
 const defaultIdleTimeout = 30 * 24 * time.Hour
@@ -79,7 +80,7 @@ func New(
 		params:          &params,
 		log:             params.Logger.Get(),
 		hc:              params.Healthcheck,
-		broker:          broker.New(),
+		broker:          params.Broker,
 		hashcashVal:     hashcash.NewValidator(resource),
 		channelHashcash: hashcash.NewChannelValidator(),
 		loginLimiter:    ratelimit.New(loginRate, loginBurst),

internal/ircserver/conn.go

@@ -0,0 +1,551 @@
+package ircserver
+
+import (
+	"bufio"
+	"context"
+	"encoding/json"
+	"fmt"
+	"log/slog"
+	"net"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"git.eeqj.de/sneak/neoirc/internal/broker"
+	"git.eeqj.de/sneak/neoirc/internal/config"
+	"git.eeqj.de/sneak/neoirc/internal/db"
+	"git.eeqj.de/sneak/neoirc/pkg/irc"
+)
+
+const (
+	maxLineLen     = 512
+	readTimeout    = 5 * time.Minute
+	writeTimeout   = 30 * time.Second
+	dnsTimeout     = 3 * time.Second
+	pollInterval   = 100 * time.Millisecond
+	pingInterval   = 90 * time.Second
+	pongDeadline   = 30 * time.Second
+	maxNickLen     = 32
+	minPasswordLen = 8
+)
+
+// Conn represents a single IRC client TCP connection.
+type Conn struct {
+	conn      net.Conn
+	log       *slog.Logger
+	database  *db.Database
+	brk       *broker.Broker
+	cfg       *config.Config
+	serverSfx string
+
+	mu        sync.Mutex
+	nick      string
+	username  string
+	realname  string
+	hostname  string
+	remoteIP  string
+	sessionID int64
+	clientID  int64
+
+	registered bool
+	gotNick    bool
+	gotUser    bool
+	passWord   string
+
+	lastQueueID int64
+	closed      bool
+	cancel      context.CancelFunc
+}
+
+func newConn(
+	ctx context.Context,
+	tcpConn net.Conn,
+	log *slog.Logger,
+	database *db.Database,
+	brk *broker.Broker,
+	cfg *config.Config,
+) *Conn {
+	host, _, _ := net.SplitHostPort(tcpConn.RemoteAddr().String())
+
+	srvName := cfg.ServerName
+	if srvName == "" {
+		srvName = "neoirc"
+	}
+
+	return &Conn{ //nolint:exhaustruct // zero-value defaults
+		conn:      tcpConn,
+		log:       log,
+		database:  database,
+		brk:       brk,
+		cfg:       cfg,
+		serverSfx: srvName,
+		remoteIP:  host,
+		hostname:  resolveHost(ctx, host),
+	}
+}
+
+// resolveHost does a reverse DNS lookup, returning the IP
+// on failure.
+func resolveHost(ctx context.Context, addr string) string {
+	ctx, cancel := context.WithTimeout(ctx, dnsTimeout)
+	defer cancel()
+
+	resolver := &net.Resolver{} //nolint:exhaustruct
+
+	names, err := resolver.LookupAddr(ctx, addr)
+	if err != nil || len(names) == 0 {
+		return addr
+	}
+
+	return strings.TrimSuffix(names[0], ".")
+}
+
+// serve is the main loop for a single IRC client connection.
+func (c *Conn) serve(ctx context.Context) {
+	ctx, c.cancel = context.WithCancel(ctx)
+	defer c.cleanup(ctx)
+
+	scanner := bufio.NewScanner(c.conn)
+	scanner.Buffer(make([]byte, maxLineLen), maxLineLen)
+
+	for {
+		_ = c.conn.SetReadDeadline(
+			time.Now().Add(readTimeout),
+		)
+
+		if !scanner.Scan() {
+			return
+		}
+
+		line := scanner.Text()
+		if line == "" {
+			continue
+		}
+
+		msg := ParseMessage(line)
+		if msg == nil {
+			continue
+		}
+
+		c.handleMessage(ctx, msg)
+
+		if c.closed {
+			return
+		}
+	}
+}
+
+func (c *Conn) cleanup(ctx context.Context) {
+	c.mu.Lock()
+	wasRegistered := c.registered
+	sessID := c.sessionID
+	nick := c.nick
+	c.closed = true
+	c.mu.Unlock()
+
+	if wasRegistered && sessID > 0 {
+		c.broadcastQuit(ctx, nick, "Connection closed")
+		c.database.DeleteSession(ctx, sessID) //nolint:errcheck,gosec
+	}
+
+	c.conn.Close() //nolint:errcheck,gosec
+}
+
+func (c *Conn) broadcastQuit(
+	ctx context.Context,
+	nick, reason string,
+) {
+	channels, err := c.database.GetSessionChannels(
+		ctx, c.sessionID,
+	)
+	if err != nil {
+		return
+	}
+
+	notified := make(map[int64]bool)
+
+	for _, ch := range channels {
+		chID, getErr := c.database.GetChannelByName(
+			ctx, ch.Name,
+		)
+		if getErr != nil {
+			continue
+		}
+
+		memberIDs, memErr := c.database.GetChannelMemberIDs(
+			ctx, chID,
+		)
+		if memErr != nil {
+			continue
+		}
+
+		for _, mid := range memberIDs {
+			if mid == c.sessionID || notified[mid] {
+				continue
+			}
+
+			notified[mid] = true
+		}
+	}
+
+	body, _ := json.Marshal([]string{reason}) //nolint:errchkjson
+
+	for sid := range notified {
+		dbID, _, insErr := c.database.InsertMessage(
+			ctx, irc.CmdQuit, nick, "", nil, body, nil,
+		)
+		if insErr != nil {
+			continue
+		}
+
+		_ = c.database.EnqueueToSession(ctx, sid, dbID)
+		c.brk.Notify(sid)
+	}
+
+	// Part from all channels so they get cleaned up.
+	for _, ch := range channels {
+		c.database.PartChannel(ctx, ch.ID, c.sessionID) //nolint:errcheck,gosec
+		c.database.DeleteChannelIfEmpty(ctx, ch.ID)     //nolint:errcheck,gosec
+	}
+}
+
+// send writes a formatted IRC line to the connection.
+func (c *Conn) send(line string) {
+	_ = c.conn.SetWriteDeadline(
+		time.Now().Add(writeTimeout),
+	)
+
+	_, _ = fmt.Fprintf(c.conn, "%s\r\n", line)
+}
+
+// sendNumeric sends a numeric reply from the server.
+func (c *Conn) sendNumeric(
+	code irc.IRCMessageType,
+	params ...string,
+) {
+	nick := c.nick
+	if nick == "" {
+		nick = "*"
+	}
+
+	allParams := make([]string, 0, 1+len(params))
+	allParams = append(allParams, nick)
+	allParams = append(allParams, params...)
+
+	c.send(FormatMessage(
+		c.serverSfx, code.Code(), allParams...,
+	))
+}
+
+// sendFromServer sends a message from the server.
+func (c *Conn) sendFromServer(
+	command string, params ...string,
+) {
+	c.send(FormatMessage(c.serverSfx, command, params...))
+}
+
+// hostmask returns the client's full hostmask
+// (nick!user@host).
+func (c *Conn) hostmask() string {
+	user := c.username
+	if user == "" {
+		user = c.nick
+	}
+
+	host := c.hostname
+	if host == "" {
+		host = c.remoteIP
+	}
+
+	return c.nick + "!" + user + "@" + host
+}
+
+// handleMessage dispatches a parsed IRC message.
+//
+//nolint:cyclop // dispatch table is inherently branchy
+func (c *Conn) handleMessage(
+	ctx context.Context,
+	msg *Message,
+) {
+	// Before registration, only NICK, USER, PASS, PING,
+	// QUIT, and CAP are accepted.
+	if !c.registered {
+		c.handlePreRegistration(ctx, msg)
+
+		return
+	}
+
+	switch msg.Command {
+	case irc.CmdPing:
+		c.handlePing(msg)
+	case "PONG":
+		// Silently accept.
+	case irc.CmdNick:
+		c.handleNick(ctx, msg)
+	case irc.CmdPrivmsg, irc.CmdNotice:
+		c.handlePrivmsg(ctx, msg)
+	case irc.CmdJoin:
+		c.handleJoin(ctx, msg)
+	case irc.CmdPart:
+		c.handlePart(ctx, msg)
+	case irc.CmdQuit:
+		c.handleQuit(msg)
+	case irc.CmdTopic:
+		c.handleTopic(ctx, msg)
+	case irc.CmdMode:
+		c.handleMode(ctx, msg)
+	case irc.CmdNames:
+		c.handleNames(ctx, msg)
+	case irc.CmdList:
+		c.handleList(ctx)
+	case irc.CmdWhois:
+		c.handleWhois(ctx, msg)
+	case irc.CmdWho:
+		c.handleWho(ctx, msg)
+	case irc.CmdLusers:
+		c.handleLusers(ctx)
+	case irc.CmdMotd:
+		c.deliverMOTD()
+	case irc.CmdOper:
+		c.handleOper(ctx, msg)
+	case irc.CmdAway:
+		c.handleAway(ctx, msg)
+	case irc.CmdKick:
+		c.handleKick(ctx, msg)
+	case irc.CmdPass:
+		c.handlePassPostReg(ctx, msg)
+	case "INVITE":
+		c.handleInvite(ctx, msg)
+	case "CAP":
+		c.handleCAP(msg)
+	case "USERHOST":
+		c.handleUserhost(ctx, msg)
+	default:
+		c.sendNumeric(
+			irc.ErrUnknownCommand,
+			msg.Command, "Unknown command",
+		)
+	}
+}
+
+// handlePreRegistration handles messages before the
+// connection is registered (NICK+USER received).
+func (c *Conn) handlePreRegistration(
+	ctx context.Context,
+	msg *Message,
+) {
+	switch msg.Command {
+	case irc.CmdPass:
+		if len(msg.Params) < 1 {
+			c.sendNumeric(
+				irc.ErrNeedMoreParams,
+				"PASS", "Not enough parameters",
+			)
+
+			return
+		}
+
+		c.passWord = msg.Params[0]
+	case irc.CmdNick:
+		if len(msg.Params) < 1 {
+			c.sendNumeric(
+				irc.ErrNoNicknameGiven,
+				"No nickname given",
+			)
+
+			return
+		}
+
+		c.nick = msg.Params[0]
+		if len(c.nick) > maxNickLen {
+			c.nick = c.nick[:maxNickLen]
+		}
+
+		c.gotNick = true
+	case irc.CmdUser:
+		if len(msg.Params) < 4 { //nolint:mnd
+			c.sendNumeric(
+				irc.ErrNeedMoreParams,
+				"USER", "Not enough parameters",
+			)
+
+			return
+		}
+
+		c.username = msg.Params[0]
+		c.realname = msg.Params[3]
+		c.gotUser = true
+	case irc.CmdPing:
+		c.handlePing(msg)
+
+		return
+	case irc.CmdQuit:
+		c.handleQuit(msg)
+
+		return
+	case "CAP":
+		c.handleCAP(msg)
+
+		return
+	default:
+		c.sendNumeric(
+			irc.ErrNotRegistered,
+			"You have not registered",
+		)
+
+		return
+	}
+
+	// Try to complete registration once we have both
+	// NICK and USER.
+	if c.gotNick && c.gotUser {
+		c.completeRegistration(ctx)
+	}
+}
+
+// completeRegistration creates a session and sends the
+// welcome burst.
+func (c *Conn) completeRegistration(ctx context.Context) {
+	// Check if nick is valid.
+	if c.nick == "" {
+		c.sendNumeric(
+			irc.ErrNoNicknameGiven, "No nickname given",
+		)
+
+		return
+	}
+
+	// Create session in DB.
+	sessionID, clientID, _, err := c.database.CreateSession(
+		ctx, c.nick, c.username, c.hostname, c.remoteIP,
+	)
+	if err != nil {
+		if strings.Contains(err.Error(), "UNIQUE constraint") ||
+			strings.Contains(err.Error(), "nick") {
+			c.sendNumeric(
+				irc.ErrNicknameInUse,
+				c.nick, "Nickname is already in use",
+			)
+
+			return
+		}
+
+		c.log.Error(
+			"failed to create session", "error", err,
+		)
+		c.send("ERROR :Internal server error")
+		c.closed = true
+
+		return
+	}
+
+	c.mu.Lock()
+	c.sessionID = sessionID
+	c.clientID = clientID
+	c.registered = true
+	c.mu.Unlock()
+
+	// If PASS was provided before registration, set the
+	// session password.
+	if c.passWord != "" && len(c.passWord) >= minPasswordLen {
+		c.setPassword(ctx, c.passWord)
+	}
+
+	// Send welcome burst.
+	c.deliverWelcome()
+	c.deliverLusers(ctx)
+	c.deliverMOTD()
+
+	// Start the message relay goroutine.
+	go c.relayMessages(ctx)
+}
+
+// deliverWelcome sends 001-005 welcome numerics.
+func (c *Conn) deliverWelcome() {
+	c.sendNumeric(irc.RplWelcome, fmt.Sprintf(
+		"Welcome to the %s Network, %s",
+		c.serverSfx, c.hostmask(),
+	))
+	c.sendNumeric(irc.RplYourHost, fmt.Sprintf(
+		"Your host is %s, running version neoirc",
+		c.serverSfx,
+	))
+	c.sendNumeric(
+		irc.RplCreated,
+		"This server was created recently",
+	)
+	c.sendNumeric(
+		irc.RplMyInfo,
+		c.serverSfx, "neoirc", "", "mnst",
+	)
+	c.sendNumeric(
+		irc.RplIsupport,
+		"CHANTYPES=#",
+		"NICKLEN=32",
+		"PREFIX=(ov)@+",
+		"CHANMODES=,,H,mnst",
+		"NETWORK="+c.serverSfx,
+		"are supported by this server",
+	)
+}
+
+// deliverLusers sends 251/252/254/255 server statistics.
+func (c *Conn) deliverLusers(ctx context.Context) {
+	users, _ := c.database.GetUserCount(ctx)
+	opers, _ := c.database.GetOperCount(ctx)
+	channels, _ := c.database.GetChannelCount(ctx)
+
+	c.sendNumeric(irc.RplLuserClient, fmt.Sprintf(
+		"There are %d users and 0 invisible on 1 servers",
+		users,
+	))
+	c.sendNumeric(
+		irc.RplLuserOp,
+		strconv.FormatInt(opers, 10),
+		"operator(s) online",
+	)
+	c.sendNumeric(
+		irc.RplLuserChannels,
+		strconv.FormatInt(channels, 10),
+		"channels formed",
+	)
+	c.sendNumeric(irc.RplLuserMe, fmt.Sprintf(
+		"I have %d clients and 1 servers", users,
+	))
+}
+
+// deliverMOTD sends 375/372/376 MOTD lines.
+func (c *Conn) deliverMOTD() {
+	motd := c.cfg.MOTD
+	if motd == "" {
+		c.sendNumeric(
+			irc.ErrNoMotd, "MOTD File is missing",
+		)
+
+		return
+	}
+
+	c.sendNumeric(irc.RplMotdStart, fmt.Sprintf(
+		"- %s Message of the Day -", c.serverSfx,
+	))
+
+	for _, line := range strings.Split(motd, "\n") {
+		c.sendNumeric(irc.RplMotd, "- "+line)
+	}
+
+	c.sendNumeric(
+		irc.RplEndOfMotd, "End of /MOTD command",
+	)
+}
+
+// setPassword sets a bcrypt password on the session.
+func (c *Conn) setPassword(ctx context.Context, pw string) {
+	// Use the database's auth module to hash and store.
+	err := c.database.SetPassword(ctx, c.sessionID, pw)
+	if err != nil {
+		c.log.Error(
+			"failed to set password", "error", err,
+		)
+	}
+}

internal/ircserver/export_test.go

@@ -0,0 +1,43 @@
+package ircserver
+
+import (
+	"context"
+	"log/slog"
+	"net"
+
+	"git.eeqj.de/sneak/neoirc/internal/broker"
+	"git.eeqj.de/sneak/neoirc/internal/config"
+	"git.eeqj.de/sneak/neoirc/internal/db"
+)
+
+// NewTestServer creates a Server suitable for testing.
+// The caller must call Stop() when finished.
+func NewTestServer(
+	log *slog.Logger,
+	cfg *config.Config,
+	database *db.Database,
+	brk *broker.Broker,
+) *Server {
+	return &Server{ //nolint:exhaustruct
+		log:      log,
+		cfg:      cfg,
+		database: database,
+		brk:      brk,
+		conns:    make(map[*Conn]struct{}),
+	}
+}
+
+// Start exposes the unexported start method for tests.
+func (s *Server) Start(addr string) error {
+	return s.start(context.Background(), addr)
+}
+
+// Stop exposes the unexported stop method for tests.
+func (s *Server) Stop() {
+	s.stop()
+}
+
+// Listener returns the server's net.Listener for tests.
+func (s *Server) Listener() net.Listener {
+	return s.listener
+}

internal/ircserver/parser.go

@@ -0,0 +1,123 @@
+// Package ircserver implements a traditional IRC wire protocol
+// listener (RFC 1459/2812) that bridges to the neoirc HTTP/JSON
+// server internals.
+package ircserver
+
+import "strings"
+
+// Message represents a parsed IRC wire protocol message.
+type Message struct {
+	// Prefix is the optional :prefix at the start (may be
+	// empty for client-to-server messages).
+	Prefix string
+	// Command is the IRC command (e.g., "PRIVMSG", "NICK").
+	Command string
+	// Params holds the positional parameters, including the
+	// trailing parameter (which was preceded by ':' on the
+	// wire).
+	Params []string
+}
+
+// ParseMessage parses a single IRC wire protocol line
+// (without the trailing CR-LF) into a Message.
+// Returns nil if the line is empty.
+//
+// IRC message format (RFC 1459 §2.3.1):
+//
+//	[":" prefix SPACE] command { SPACE param } [SPACE ":" trailing]
+func ParseMessage(line string) *Message {
+	if line == "" {
+		return nil
+	}
+
+	msg := &Message{} //nolint:exhaustruct // fields set below
+
+	// Extract prefix if present.
+	if line[0] == ':' {
+		idx := strings.IndexByte(line, ' ')
+		if idx < 0 {
+			// Only a prefix, no command — invalid.
+			return nil
+		}
+
+		msg.Prefix = line[1:idx]
+		line = line[idx+1:]
+	}
+
+	// Skip leading spaces.
+	line = strings.TrimLeft(line, " ")
+	if line == "" {
+		return nil
+	}
+
+	// Extract command.
+	idx := strings.IndexByte(line, ' ')
+	if idx < 0 {
+		msg.Command = strings.ToUpper(line)
+
+		return msg
+	}
+
+	msg.Command = strings.ToUpper(line[:idx])
+	line = line[idx+1:]
+
+	// Extract parameters.
+	for line != "" {
+		line = strings.TrimLeft(line, " ")
+		if line == "" {
+			break
+		}
+
+		// Trailing parameter (everything after ':').
+		if line[0] == ':' {
+			msg.Params = append(msg.Params, line[1:])
+
+			break
+		}
+
+		idx = strings.IndexByte(line, ' ')
+		if idx < 0 {
+			msg.Params = append(msg.Params, line)
+
+			break
+		}
+
+		msg.Params = append(msg.Params, line[:idx])
+		line = line[idx+1:]
+	}
+
+	return msg
+}
+
+// FormatMessage formats an IRC message into wire protocol
+// format (without the trailing CR-LF).
+func FormatMessage(
+	prefix, command string,
+	params ...string,
+) string {
+	var buf strings.Builder
+
+	if prefix != "" {
+		buf.WriteByte(':')
+		buf.WriteString(prefix)
+		buf.WriteByte(' ')
+	}
+
+	buf.WriteString(command)
+
+	for i, param := range params {
+		buf.WriteByte(' ')
+
+		isLast := i == len(params)-1
+		needsColon := strings.Contains(param, " ") ||
+			param == "" || param[0] == ':'
+
+		if isLast && needsColon {
+			buf.WriteByte(':')
+		}
+
+		buf.WriteString(param)
+	}
+
+	return buf.String()
+}

internal/ircserver/parser_test.go

@@ -0,0 +1,328 @@
+package ircserver_test
+
+import (
+	"testing"
+
+	"git.eeqj.de/sneak/neoirc/internal/ircserver"
+)
+
+//nolint:funlen // table-driven test
+func TestParseMessage(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name    string
+		input   string
+		want    *ircserver.Message
+		wantNil bool
+	}{
+		{
+			name:    "empty",
+			input:   "",
+			want:    nil,
+			wantNil: true,
+		},
+		{
+			name:  "simple command",
+			input: "PING",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "PING",
+				Params:  nil,
+			},
+			wantNil: false,
+		},
+		{
+			name:  "command with one param",
+			input: "NICK alice",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "NICK",
+				Params:  []string{"alice"},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "command case insensitive",
+			input: "nick Alice",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "NICK",
+				Params:  []string{"Alice"},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "privmsg with trailing",
+			input: "PRIVMSG #general :hello world",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "PRIVMSG",
+				Params:  []string{"#general", "hello world"},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "with prefix",
+			input: ":server.example.com 001 alice :Welcome to IRC",
+			want: &ircserver.Message{
+				Prefix:  "server.example.com",
+				Command: "001",
+				Params:  []string{"alice", "Welcome to IRC"},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "user command",
+			input: "USER alice 0 * :Alice Smith",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "USER",
+				Params: []string{
+					"alice", "0", "*", "Alice Smith",
+				},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "join channel",
+			input: "JOIN #general",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "JOIN",
+				Params:  []string{"#general"},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "quit with trailing",
+			input: "QUIT :leaving now",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "QUIT",
+				Params:  []string{"leaving now"},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "quit without reason",
+			input: "QUIT",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "QUIT",
+				Params:  nil,
+			},
+			wantNil: false,
+		},
+		{
+			name:  "mode query",
+			input: "MODE #general",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "MODE",
+				Params:  []string{"#general"},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "kick with reason",
+			input: "KICK #general bob :misbehaving",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "KICK",
+				Params: []string{
+					"#general", "bob", "misbehaving",
+				},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "empty trailing",
+			input: "PRIVMSG #general :",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "PRIVMSG",
+				Params:  []string{"#general", ""},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "pass command",
+			input: "PASS mysecret",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "PASS",
+				Params:  []string{"mysecret"},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "ping with server",
+			input: "PING :irc.example.com",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "PING",
+				Params:  []string{"irc.example.com"},
+			},
+			wantNil: false,
+		},
+		{
+			name:  "topic with trailing spaces",
+			input: "TOPIC #general :Welcome to the channel!",
+			want: &ircserver.Message{
+				Prefix:  "",
+				Command: "TOPIC",
+				Params: []string{
+					"#general",
+					"Welcome to the channel!",
+				},
+			},
+			wantNil: false,
+		},
+	}
+
+	for _, testCase := range tests {
+		t.Run(testCase.name, func(t *testing.T) {
+			t.Parallel()
+
+			got := ircserver.ParseMessage(testCase.input)
+			if testCase.wantNil {
+				if got != nil {
+					t.Fatalf("expected nil, got %+v", got)
+				}
+
+				return
+			}
+
+			if got == nil {
+				t.Fatal("expected non-nil message")
+			}
+
+			if got.Prefix != testCase.want.Prefix {
+				t.Errorf(
+					"prefix: got %q, want %q",
+					got.Prefix, testCase.want.Prefix,
+				)
+			}
+
+			if got.Command != testCase.want.Command {
+				t.Errorf(
+					"command: got %q, want %q",
+					got.Command, testCase.want.Command,
+				)
+			}
+
+			if len(got.Params) != len(testCase.want.Params) {
+				t.Fatalf(
+					"params length: got %d, want %d (%v vs %v)",
+					len(got.Params),
+					len(testCase.want.Params),
+					got.Params,
+					testCase.want.Params,
+				)
+			}
+
+			for i, p := range got.Params {
+				if p != testCase.want.Params[i] {
+					t.Errorf(
+						"param[%d]: got %q, want %q",
+						i, p, testCase.want.Params[i],
+					)
+				}
+			}
+		})
+	}
+}
+
+func TestFormatMessage(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name    string
+		prefix  string
+		command string
+		params  []string
+		want    string
+	}{
+		{
+			name:    "simple command",
+			prefix:  "",
+			command: "PING",
+			params:  nil,
+			want:    "PING",
+		},
+		{
+			name:    "with prefix",
+			prefix:  "server",
+			command: "PONG",
+			params:  []string{"server"},
+			want:    ":server PONG server",
+		},
+		{
+			name:    "privmsg with trailing",
+			prefix:  "alice!alice@host",
+			command: "PRIVMSG",
+			params:  []string{"#general", "hello world"},
+			want:    ":alice!alice@host PRIVMSG #general :hello world",
+		},
+		{
+			name:    "numeric reply",
+			prefix:  "server",
+			command: "001",
+			params:  []string{"alice", "Welcome to IRC"},
+			want:    ":server 001 alice :Welcome to IRC",
+		},
+		{
+			name:    "empty trailing",
+			prefix:  "server",
+			command: "PRIVMSG",
+			params:  []string{"#chan", ""},
+			want:    ":server PRIVMSG #chan :",
+		},
+	}
+
+	for _, testCase := range tests {
+		t.Run(testCase.name, func(t *testing.T) {
+			t.Parallel()
+
+			got := ircserver.FormatMessage(
+				testCase.prefix, testCase.command, testCase.params...,
+			)
+			if got != testCase.want {
+				t.Errorf("got %q, want %q", got, testCase.want)
+			}
+		})
+	}
+}
+
+func TestParseFormatRoundTrip(t *testing.T) {
+	t.Parallel()
+
+	// Round-trip only works for lines where the last
+	// parameter either contains a space (gets ':' prefix
+	// on format) or is a non-trailing single token.
+	lines := []string{
+		"PING",
+		"NICK alice",
+		"PRIVMSG #general :hello world",
+		"JOIN #general",
+		"MODE #general",
+	}
+
+	for _, line := range lines {
+		msg := ircserver.ParseMessage(line)
+		if msg == nil {
+			t.Fatalf("failed to parse: %q", line)
+		}
+
+		formatted := ircserver.FormatMessage(
+			msg.Prefix, msg.Command, msg.Params...,
+		)
+		if formatted != line {
+			t.Errorf(
+				"round-trip failed: input %q, got %q",
+				line, formatted,
+			)
+		}
+	}
+}

internal/ircserver/relay.go

@@ -0,0 +1,319 @@
+package ircserver
+
+import (
+	"context"
+	"encoding/json"
+	"strings"
+	"time"
+
+	"git.eeqj.de/sneak/neoirc/internal/db"
+	"git.eeqj.de/sneak/neoirc/pkg/irc"
+)
+
+// relayMessages polls the client output queue and delivers
+// IRC-formatted messages to the TCP connection.  It runs
+// in a goroutine for the lifetime of the connection.
+func (c *Conn) relayMessages(ctx context.Context) {
+	// Use a ticker as a fallback; primary wakeup is via
+	// broker notification.
+	ticker := time.NewTicker(pollInterval)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		default:
+		}
+
+		// Drain any available messages.
+		delivered := c.drainQueue(ctx)
+
+		if delivered {
+			// Tight loop while there are messages.
+			continue
+		}
+
+		// Wait for notification or timeout.
+		waitCh := c.brk.Wait(c.sessionID)
+
+		select {
+		case <-waitCh:
+			// New message notification — loop back.
+		case <-ticker.C:
+			// Periodic check.
+		case <-ctx.Done():
+			c.brk.Remove(c.sessionID, waitCh)
+
+			return
+		}
+	}
+}
+
+const relayPollLimit = 100
+
+// drainQueue polls the output queue and delivers all
+// pending messages.  Returns true if at least one message
+// was delivered.
+func (c *Conn) drainQueue(ctx context.Context) bool {
+	msgs, lastID, err := c.database.PollMessages(
+		ctx, c.clientID, c.lastQueueID, relayPollLimit,
+	)
+	if err != nil {
+		return false
+	}
+
+	if len(msgs) == 0 {
+		return false
+	}
+
+	for i := range msgs {
+		c.deliverIRCMessage(ctx, &msgs[i])
+	}
+
+	if lastID > c.lastQueueID {
+		c.lastQueueID = lastID
+	}
+
+	return true
+}
+
+// deliverIRCMessage converts a db.IRCMessage to wire
+// protocol and sends it.
+//
+//nolint:cyclop // dispatch table
+func (c *Conn) deliverIRCMessage(
+	_ context.Context,
+	msg *db.IRCMessage,
+) {
+	command := msg.Command
+
+	// Decode body as []string for the trailing text.
+	var bodyLines []string
+
+	if msg.Body != nil {
+		_ = json.Unmarshal(msg.Body, &bodyLines)
+	}
+
+	text := ""
+	if len(bodyLines) > 0 {
+		text = bodyLines[0]
+	}
+
+	// Route by command type.
+	switch {
+	case isNumeric(command):
+		c.deliverNumeric(msg, text)
+	case command == irc.CmdPrivmsg || command == irc.CmdNotice:
+		c.deliverTextMessage(msg, command, text)
+	case command == irc.CmdJoin:
+		c.deliverJoin(msg)
+	case command == irc.CmdPart:
+		c.deliverPart(msg, text)
+	case command == irc.CmdNick:
+		c.deliverNickChange(msg, text)
+	case command == irc.CmdQuit:
+		c.deliverQuitMsg(msg, text)
+	case command == irc.CmdTopic:
+		c.deliverTopicChange(msg, text)
+	case command == irc.CmdKick:
+		c.deliverKickMsg(msg, text)
+	case command == "INVITE":
+		c.deliverInviteMsg(msg, text)
+	case command == irc.CmdMode:
+		c.deliverMode(msg, text)
+	case command == irc.CmdPing:
+		// Server-originated PING — reply with PONG.
+		c.sendFromServer("PING", c.serverSfx)
+	default:
+		// Unknown command — deliver as server notice.
+		if text != "" {
+			c.sendFromServer("NOTICE", c.nick, text)
+		}
+	}
+}
+
+// isNumeric returns true if the command is a 3-digit
+// numeric code.
+func isNumeric(cmd string) bool {
+	return len(cmd) == 3 &&
+		cmd[0] >= '0' && cmd[0] <= '9' &&
+		cmd[1] >= '0' && cmd[1] <= '9' &&
+		cmd[2] >= '0' && cmd[2] <= '9'
+}
+
+// deliverNumeric sends a numeric reply.
+func (c *Conn) deliverNumeric(
+	msg *db.IRCMessage,
+	text string,
+) {
+	from := msg.From
+	if from == "" {
+		from = c.serverSfx
+	}
+
+	var params []string
+
+	if msg.Params != nil {
+		_ = json.Unmarshal(msg.Params, &params)
+	}
+
+	allParams := make([]string, 0, 1+len(params)+1)
+	allParams = append(allParams, c.nick)
+	allParams = append(allParams, params...)
+
+	if text != "" {
+		allParams = append(allParams, text)
+	}
+
+	c.send(FormatMessage(from, msg.Command, allParams...))
+}
+
+// deliverTextMessage sends PRIVMSG or NOTICE.
+func (c *Conn) deliverTextMessage(
+	msg *db.IRCMessage,
+	command, text string,
+) {
+	from := msg.From
+	target := msg.To
+
+	// Don't echo our own messages back.
+	if strings.EqualFold(from, c.nick) {
+		return
+	}
+
+	prefix := from
+	if !strings.Contains(prefix, "!") {
+		prefix = from + "!" + from + "@*"
+	}
+
+	c.send(FormatMessage(prefix, command, target, text))
+}
+
+// deliverJoin sends a JOIN notification.
+func (c *Conn) deliverJoin(msg *db.IRCMessage) {
+	// Don't echo our own JOINs (we already sent them
+	// during joinChannel).
+	if strings.EqualFold(msg.From, c.nick) {
+		return
+	}
+
+	prefix := msg.From + "!" + msg.From + "@*"
+	channel := msg.To
+
+	c.send(FormatMessage(prefix, "JOIN", channel))
+}
+
+// deliverPart sends a PART notification.
+func (c *Conn) deliverPart(msg *db.IRCMessage, text string) {
+	if strings.EqualFold(msg.From, c.nick) {
+		return
+	}
+
+	prefix := msg.From + "!" + msg.From + "@*"
+	channel := msg.To
+
+	if text != "" {
+		c.send(FormatMessage(
+			prefix, "PART", channel, text,
+		))
+	} else {
+		c.send(FormatMessage(prefix, "PART", channel))
+	}
+}
+
+// deliverNickChange sends a NICK change notification.
+func (c *Conn) deliverNickChange(
+	msg *db.IRCMessage,
+	newNick string,
+) {
+	if strings.EqualFold(msg.From, c.nick) {
+		return
+	}
+
+	prefix := msg.From + "!" + msg.From + "@*"
+
+	c.send(FormatMessage(prefix, "NICK", newNick))
+}
+
+// deliverQuitMsg sends a QUIT notification.
+func (c *Conn) deliverQuitMsg(
+	msg *db.IRCMessage,
+	text string,
+) {
+	if strings.EqualFold(msg.From, c.nick) {
+		return
+	}
+
+	prefix := msg.From + "!" + msg.From + "@*"
+
+	if text != "" {
+		c.send(FormatMessage(
+			prefix, "QUIT", "Quit: "+text,
+		))
+	} else {
+		c.send(FormatMessage(prefix, "QUIT", "Quit"))
+	}
+}
+
+// deliverTopicChange sends a TOPIC change notification.
+func (c *Conn) deliverTopicChange(
+	msg *db.IRCMessage,
+	text string,
+) {
+	prefix := msg.From + "!" + msg.From + "@*"
+	channel := msg.To
+
+	c.send(FormatMessage(prefix, "TOPIC", channel, text))
+}
+
+// deliverKickMsg sends a KICK notification.
+func (c *Conn) deliverKickMsg(
+	msg *db.IRCMessage,
+	text string,
+) {
+	prefix := msg.From + "!" + msg.From + "@*"
+	channel := msg.To
+
+	var params []string
+
+	if msg.Params != nil {
+		_ = json.Unmarshal(msg.Params, &params)
+	}
+
+	kickTarget := ""
+	if len(params) > 0 {
+		kickTarget = params[0]
+	}
+
+	if kickTarget != "" {
+		c.send(FormatMessage(
+			prefix, "KICK", channel, kickTarget, text,
+		))
+	} else {
+		c.send(FormatMessage(
+			prefix, "KICK", channel, "?", text,
+		))
+	}
+}
+
+// deliverInviteMsg sends an INVITE notification.
+func (c *Conn) deliverInviteMsg(
+	_ *db.IRCMessage,
+	text string,
+) {
+	c.sendFromServer("NOTICE", c.nick, text)
+}
+
+// deliverMode sends a MODE change notification.
+func (c *Conn) deliverMode(
+	msg *db.IRCMessage,
+	text string,
+) {
+	prefix := msg.From + "!" + msg.From + "@*"
+	target := msg.To
+
+	if text != "" {
+		c.send(FormatMessage(prefix, "MODE", target, text))
+	}
+}

internal/ircserver/server.go

@@ -0,0 +1,153 @@
+package ircserver
+
+import (
+	"context"
+	"fmt"
+	"log/slog"
+	"net"
+	"sync"
+
+	"git.eeqj.de/sneak/neoirc/internal/broker"
+	"git.eeqj.de/sneak/neoirc/internal/config"
+	"git.eeqj.de/sneak/neoirc/internal/db"
+	"git.eeqj.de/sneak/neoirc/internal/logger"
+	"go.uber.org/fx"
+)
+
+// Params defines the dependencies for creating an IRC
+// Server.
+type Params struct {
+	fx.In
+
+	Logger   *logger.Logger
+	Config   *config.Config
+	Database *db.Database
+	Broker   *broker.Broker
+}
+
+// Server is the TCP IRC protocol server.
+type Server struct {
+	log      *slog.Logger
+	cfg      *config.Config
+	database *db.Database
+	brk      *broker.Broker
+	listener net.Listener
+	mu       sync.Mutex
+	conns    map[*Conn]struct{}
+	cancel   context.CancelFunc
+}
+
+// New creates a new IRC Server and registers its lifecycle
+// hooks.  The listener is only started if IRC_LISTEN_ADDR
+// is configured; otherwise the server is inert.
+func New(
+	lifecycle fx.Lifecycle,
+	params Params,
+) *Server {
+	srv := &Server{
+		log:      params.Logger.Get(),
+		cfg:      params.Config,
+		database: params.Database,
+		brk:      params.Broker,
+		conns:    make(map[*Conn]struct{}),
+		listener: nil,
+		cancel:   nil,
+		mu:       sync.Mutex{},
+	}
+
+	listenAddr := params.Config.IRCListenAddr
+	if listenAddr == "" {
+		return srv
+	}
+
+	lifecycle.Append(fx.Hook{
+		OnStart: func(ctx context.Context) error {
+			return srv.start(ctx, listenAddr)
+		},
+		OnStop: func(_ context.Context) error {
+			srv.stop()
+
+			return nil
+		},
+	})
+
+	return srv
+}
+
+// start begins listening for TCP connections.
+//
+//nolint:contextcheck // long-lived server ctx, not the short Fx one
+func (s *Server) start(_ context.Context, addr string) error {
+	ln, err := net.Listen("tcp", addr)
+	if err != nil {
+		return fmt.Errorf("irc listen: %w", err)
+	}
+
+	s.listener = ln
+
+	ctx, cancel := context.WithCancel(context.Background())
+	s.cancel = cancel
+
+	s.log.Info(
+		"irc server listening", "addr", addr,
+	)
+
+	go s.acceptLoop(ctx)
+
+	return nil
+}
+
+// stop shuts down the listener and all connections.
+func (s *Server) stop() {
+	if s.cancel != nil {
+		s.cancel()
+	}
+
+	if s.listener != nil {
+		s.listener.Close() //nolint:errcheck,gosec
+	}
+
+	s.mu.Lock()
+	for c := range s.conns {
+		c.conn.Close() //nolint:errcheck,gosec
+	}
+	s.mu.Unlock()
+}
+
+// acceptLoop accepts new connections.
+func (s *Server) acceptLoop(ctx context.Context) {
+	for {
+		tcpConn, err := s.listener.Accept()
+		if err != nil {
+			select {
+			case <-ctx.Done():
+				return
+			default:
+				s.log.Error(
+					"irc accept error", "error", err,
+				)
+
+				continue
+			}
+		}
+
+		client := newConn(
+			ctx, tcpConn, s.log,
+			s.database, s.brk, s.cfg,
+		)
+
+		s.mu.Lock()
+		s.conns[client] = struct{}{}
+		s.mu.Unlock()
+
+		go func() {
+			defer func() {
+				s.mu.Lock()
+				delete(s.conns, client)
+				s.mu.Unlock()
+			}()
+
+			client.serve(ctx)
+		}()
+	}
+}

internal/ircserver/server_test.go

@@ -0,0 +1,625 @@
+package ircserver_test
+
+import (
+	"bufio"
+	"database/sql"
+	"fmt"
+	"log/slog"
+	"net"
+	"os"
+	"strings"
+	"testing"
+	"time"
+
+	"git.eeqj.de/sneak/neoirc/internal/broker"
+	"git.eeqj.de/sneak/neoirc/internal/config"
+	"git.eeqj.de/sneak/neoirc/internal/db"
+	"git.eeqj.de/sneak/neoirc/internal/ircserver"
+
+	_ "modernc.org/sqlite"
+)
+
+const testTimeout = 5 * time.Second
+
+func TestMain(m *testing.M) {
+	db.SetBcryptCost(4)
+
+	os.Exit(m.Run())
+}
+
+// testEnv holds the shared test infrastructure.
+type testEnv struct {
+	database *db.Database
+	brk      *broker.Broker
+	cfg      *config.Config
+	srv      *ircserver.Server
+}
+
+func newTestEnv(t *testing.T) *testEnv {
+	t.Helper()
+
+	dsn := fmt.Sprintf(
+		"file:%s?mode=memory&cache=shared&_journal_mode=WAL",
+		t.Name(),
+	)
+
+	conn, err := sql.Open("sqlite", dsn)
+	if err != nil {
+		t.Fatalf("open db: %v", err)
+	}
+
+	conn.SetMaxOpenConns(1)
+
+	_, err = conn.ExecContext(
+		t.Context(), "PRAGMA foreign_keys = ON",
+	)
+	if err != nil {
+		t.Fatalf("pragma: %v", err)
+	}
+
+	database := db.NewTestDatabaseFromConn(conn)
+
+	err = database.RunMigrations(t.Context())
+	if err != nil {
+		t.Fatalf("migrate: %v", err)
+	}
+
+	brk := broker.New()
+
+	cfg := &config.Config{ //nolint:exhaustruct
+		ServerName: "test.irc",
+		MOTD:       "Welcome to test IRC",
+	}
+
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("listen: %v", err)
+	}
+
+	addr := listener.Addr().String()
+
+	err = listener.Close()
+	if err != nil {
+		t.Fatalf("close listener: %v", err)
+	}
+
+	log := slog.New(slog.NewTextHandler(
+		os.Stderr,
+		&slog.HandlerOptions{Level: slog.LevelError}, //nolint:exhaustruct
+	))
+
+	srv := ircserver.NewTestServer(log, cfg, database, brk)
+
+	err = srv.Start(addr)
+	if err != nil {
+		t.Fatalf("start irc server: %v", err)
+	}
+
+	t.Cleanup(func() {
+		srv.Stop()
+
+		err := conn.Close()
+		if err != nil {
+			t.Logf("close db: %v", err)
+		}
+	})
+
+	return &testEnv{
+		database: database,
+		brk:      brk,
+		cfg:      cfg,
+		srv:      srv,
+	}
+}
+
+// dial connects to the test server.
+func (env *testEnv) dial(t *testing.T) *testClient {
+	t.Helper()
+
+	conn, err := net.DialTimeout(
+		"tcp",
+		env.srv.Listener().Addr().String(),
+		testTimeout,
+	)
+	if err != nil {
+		t.Fatalf("dial: %v", err)
+	}
+
+	t.Cleanup(func() {
+		err := conn.Close()
+		if err != nil {
+			t.Logf("close conn: %v", err)
+		}
+	})
+
+	return &testClient{
+		t:       t,
+		conn:    conn,
+		scanner: bufio.NewScanner(conn),
+	}
+}
+
+// testClient wraps a raw TCP connection with helpers.
+type testClient struct {
+	t       *testing.T
+	conn    net.Conn
+	scanner *bufio.Scanner
+}
+
+func (tc *testClient) send(line string) {
+	tc.t.Helper()
+
+	_ = tc.conn.SetWriteDeadline(
+		time.Now().Add(testTimeout),
+	)
+
+	_, err := fmt.Fprintf(tc.conn, "%s\r\n", line)
+	if err != nil {
+		tc.t.Fatalf("send: %v", err)
+	}
+}
+
+func (tc *testClient) readLine() string {
+	tc.t.Helper()
+
+	_ = tc.conn.SetReadDeadline(
+		time.Now().Add(testTimeout),
+	)
+
+	if !tc.scanner.Scan() {
+		err := tc.scanner.Err()
+		if err != nil {
+			tc.t.Fatalf("read: %v", err)
+		}
+
+		tc.t.Fatal("connection closed unexpectedly")
+	}
+
+	return tc.scanner.Text()
+}
+
+// readUntil reads lines until one matches the predicate.
+func (tc *testClient) readUntil(
+	pred func(string) bool,
+) []string {
+	tc.t.Helper()
+
+	var lines []string
+
+	for {
+		line := tc.readLine()
+		lines = append(lines, line)
+
+		if pred(line) {
+			return lines
+		}
+	}
+}
+
+// register sends NICK + USER and reads through the welcome
+// burst.
+func (tc *testClient) register(nick string) []string {
+	tc.t.Helper()
+
+	tc.send("NICK " + nick)
+	tc.send("USER " + nick + " 0 * :Test User")
+
+	return tc.readUntil(func(line string) bool {
+		return strings.Contains(line, " 376 ") ||
+			strings.Contains(line, " 422 ")
+	})
+}
+
+// assertContains checks that at least one line matches the
+// given substring.
+func assertContains(
+	t *testing.T,
+	lines []string,
+	substr, description string,
+) {
+	t.Helper()
+
+	for _, line := range lines {
+		if strings.Contains(line, substr) {
+			return
+		}
+	}
+
+	t.Errorf("did not find %q in output: %s", substr, description)
+}
+
+// joinAndDrain joins a channel and reads until
+// RPL_ENDOFNAMES.
+func (tc *testClient) joinAndDrain(channel string) {
+	tc.t.Helper()
+
+	tc.send("JOIN " + channel)
+
+	tc.readUntil(func(line string) bool {
+		return strings.Contains(line, " 366 ")
+	})
+}
+
+// sendAndExpect sends a command and reads until a line
+// containing the expected substring is found.
+func (tc *testClient) sendAndExpect(
+	cmd, expect string,
+) []string {
+	tc.t.Helper()
+
+	tc.send(cmd)
+
+	return tc.readUntil(func(line string) bool {
+		return strings.Contains(line, expect)
+	})
+}
+
+func TestRegistration(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	lines := client.register("alice")
+	assertContains(t, lines, " 001 ", "RPL_WELCOME")
+}
+
+func TestWelcomeContainsNick(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	lines := client.register("bob")
+
+	for _, line := range lines {
+		if strings.Contains(line, " 001 ") &&
+			!strings.Contains(line, "bob") {
+			t.Errorf("001 should contain nick: %s", line)
+		}
+	}
+}
+
+func TestPingPong(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("pingtest")
+	lines := client.sendAndExpect("PING :hello", "PONG")
+	assertContains(t, lines, "PONG", "PONG response")
+}
+
+func TestJoinChannel(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("joiner")
+	client.send("JOIN #test")
+
+	lines := client.readUntil(func(line string) bool {
+		return strings.Contains(line, " 366 ")
+	})
+
+	assertContains(t, lines, "JOIN", "JOIN echo")
+	assertContains(t, lines, " 366 ", "RPL_ENDOFNAMES")
+}
+
+func TestPrivmsgBetweenClients(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+
+	alice := env.dial(t)
+	alice.register("alice_pm")
+
+	bob := env.dial(t)
+	bob.register("bob_pm")
+
+	alice.joinAndDrain("#chat")
+	bob.joinAndDrain("#chat")
+
+	alice.send("PRIVMSG #chat :hello bob!")
+	lines := bob.sendAndExpect("PING :sync", "hello bob!")
+	assertContains(t, lines, "hello bob!", "channel PRIVMSG")
+}
+
+func TestNickChange(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("oldnick")
+	lines := client.sendAndExpect("NICK newnick", "newnick")
+	assertContains(t, lines, "NICK", "NICK change echo")
+}
+
+func TestDuplicateNick(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+
+	first := env.dial(t)
+	first.register("taken")
+
+	second := env.dial(t)
+	second.send("NICK taken")
+	second.send("USER taken 0 * :Test")
+
+	lines := second.readUntil(func(line string) bool {
+		return strings.Contains(line, " 433 ")
+	})
+
+	assertContains(t, lines, " 433 ", "ERR_NICKNAMEINUSE")
+}
+
+func TestListChannels(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("lister")
+	client.joinAndDrain("#listtest")
+	lines := client.sendAndExpect("LIST", " 323 ")
+	assertContains(t, lines, " 323 ", "RPL_LISTEND") //nolint:misspell // IRC term
+}
+
+func TestWhois(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("whoistest")
+	lines := client.sendAndExpect(
+		"WHOIS whoistest", " 318 ",
+	)
+
+	assertContains(t, lines, " 311 ", "RPL_WHOISUSER")
+	assertContains(t, lines, " 318 ", "RPL_ENDOFWHOIS")
+}
+
+func TestQuit(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("quitter")
+	lines := client.sendAndExpect(
+		"QUIT :goodbye", "ERROR",
+	)
+
+	assertContains(t, lines, "goodbye", "QUIT reason")
+}
+
+func TestTopicSetAndGet(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("topicuser")
+	client.joinAndDrain("#topictest")
+	lines := client.sendAndExpect(
+		"TOPIC #topictest :New topic here",
+		"New topic here",
+	)
+
+	assertContains(
+		t, lines, "New topic here", "TOPIC echo",
+	)
+}
+
+func TestUnknownCommand(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("unknowncmd")
+	lines := client.sendAndExpect("FOOBAR", " 421 ")
+	assertContains(t, lines, " 421 ", "ERR_UNKNOWNCOMMAND")
+}
+
+func TestDirectMessage(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+
+	sender := env.dial(t)
+	sender.register("dmsender")
+
+	receiver := env.dial(t)
+	receiver.register("dmreceiver")
+
+	// Give relay goroutines time to start.
+	time.Sleep(100 * time.Millisecond)
+
+	sender.send("PRIVMSG dmreceiver :hello privately")
+
+	lines := receiver.readUntil(func(line string) bool {
+		return strings.Contains(line, "hello privately")
+	})
+
+	assertContains(
+		t, lines, "hello privately", "direct PRIVMSG",
+	)
+}
+
+func TestCAPNegotiation(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.send("CAP LS 302")
+
+	line := client.readLine()
+	if !strings.Contains(line, "CAP") {
+		t.Errorf("expected CAP response, got: %s", line)
+	}
+
+	client.send("CAP END")
+	lines := client.register("capuser")
+	assertContains(t, lines, " 001 ", "registration after CAP")
+}
+
+func TestPartChannel(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("parter")
+	client.joinAndDrain("#parttest")
+	lines := client.sendAndExpect(
+		"PART #parttest :leaving", "PART",
+	)
+
+	assertContains(t, lines, "#parttest", "PART echo")
+}
+
+func TestModeQuery(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("modeuser")
+	client.joinAndDrain("#modetest")
+	lines := client.sendAndExpect(
+		"MODE #modetest", " 324 ",
+	)
+
+	assertContains(
+		t, lines, " 324 ", "RPL_CHANNELMODEIS",
+	)
+}
+
+func TestWhoChannel(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("whouser")
+	client.joinAndDrain("#whotest")
+	lines := client.sendAndExpect("WHO #whotest", " 315 ")
+	assertContains(t, lines, " 352 ", "RPL_WHOREPLY")
+}
+
+func TestLusers(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("luseruser")
+	lines := client.sendAndExpect("LUSERS", " 255 ")
+	assertContains(t, lines, " 251 ", "RPL_LUSERCLIENT")
+}
+
+func TestMotd(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("motduser")
+	lines := client.sendAndExpect("MOTD", " 376 ")
+	assertContains(t, lines, " 376 ", "RPL_ENDOFMOTD")
+}
+
+func TestAwaySetAndClear(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("awayuser")
+
+	setLines := client.sendAndExpect(
+		"AWAY :brb lunch", " 306 ",
+	)
+	assertContains(t, setLines, " 306 ", "RPL_NOWAWAY")
+
+	clearLines := client.sendAndExpect("AWAY", " 305 ")
+	assertContains(t, clearLines, " 305 ", "RPL_UNAWAY")
+}
+
+func TestHandlePassPostRegistration(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("passuser")
+	lines := client.sendAndExpect(
+		"PASS :mypassword123", "Password set",
+	)
+
+	assertContains(
+		t, lines, "Password set", "password confirmation",
+	)
+}
+
+func TestPreRegistrationNotRegistered(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.send("PRIVMSG #test :hello")
+
+	line := client.readLine()
+	if !strings.Contains(line, " 451 ") {
+		t.Errorf(
+			"expected ERR_NOTREGISTERED (451), got: %s",
+			line,
+		)
+	}
+}
+
+func TestNamesNonExistentChannel(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+
+	client.register("namesuser")
+	lines := client.sendAndExpect(
+		"NAMES #doesnotexist", " 366 ",
+	)
+
+	assertContains(
+		t, lines, " 366 ",
+		"RPL_ENDOFNAMES for non-existent channel",
+	)
+}
+
+func BenchmarkParseMessage(b *testing.B) {
+	line := ":nick!user@host PRIVMSG #channel :Hello, world!"
+
+	b.ResetTimer()
+
+	for range b.N {
+		_ = ircserver.ParseMessage(line)
+	}
+}
+
+func BenchmarkFormatMessage(b *testing.B) {
+	b.ResetTimer()
+
+	for range b.N {
+		_ = ircserver.FormatMessage(
+			"nick!user@host", "PRIVMSG",
+			"#channel", "Hello, world!",
+		)
+	}
+}

pkg/irc/commands.go

@@ -21,6 +21,7 @@ const (
 	CmdPrivmsg = "PRIVMSG"
 	CmdQuit    = "QUIT"
 	CmdTopic   = "TOPIC"
+	CmdUser    = "USER"
 	CmdWho     = "WHO"
 	CmdWhois   = "WHOIS"
 )