reorganize parsing code

src/irc/commands.go

@@ -1,27 +1,13 @@
 package irc
 
-import (
-	"strconv"
-	"strings"
-)
-
 type Message interface {
 	Handle(s *Server, c *Client)
 }
 
-type NewMessageFunc func([]string) Message
-
 type NickMessage struct {
 	nickname string
 }
 
-func NewNickMessage(args []string) Message {
-	if len(args) != 1 {
-		return nil
-	}
-	return &NickMessage{args[0]}
-}
-
 func (m *NickMessage) Handle(s *Server, c *Client) {
 	if s.nicks[m.nickname] != nil {
 		c.send <- ErrNickNameInUse(m.nickname)
@@ -42,21 +28,6 @@ type UserMessage struct {
 	realname string
 }
 
-func NewUserMessage(args []string) Message {
-	if len(args) != 4 {
-		return nil
-	}
-	msg := new(UserMessage)
-	msg.user = args[0]
-	mode, err := strconv.ParseUint(args[1], 10, 8)
-	if err == nil {
-		msg.mode = uint8(mode)
-	}
-	msg.unused = args[2]
-	msg.realname = args[3]
-	return msg
-}
-
 func (m *UserMessage) Handle(s *Server, c *Client) {
 	if c.username != "" {
 		c.send <- ErrAlreadyRegistered(c.Nick())
@@ -70,14 +41,6 @@ type QuitMessage struct {
 	message string
 }
 
-func NewQuitMessage(args []string) Message {
-	msg := QuitMessage{}
-	if len(args) > 0 {
-		msg.message = args[0]
-	}
-	return &msg
-}
-
 func (m *QuitMessage) Handle(s *Server, c *Client) {
 	c.send <- MessageError()
 	delete(s.nicks, c.nick)
@@ -93,10 +56,6 @@ func (m *UnknownMessage) Handle(s *Server, c *Client) {
 
 type PingMessage struct {}
 
-func NewPingMessage(args []string) Message {
-	return &PingMessage{}
-}
-
 func (m *PingMessage) Handle(s *Server, c *Client) {
 	c.send <- MessagePong()
 }
@@ -110,49 +69,3 @@ func tryRegister(s *Server, c *Client) {
 		c.send <- ReplyMyInfo(c.Nick(), "irc.jlatt.com")
 	}
 }
-
-func parseArg(line string) (string, string) {
-	if line == "" {
-		return "", ""
-	}
-
-	if strings.HasPrefix(line, ":") {
-		return line[1:], ""
-	}
-
-	parts := strings.SplitN(line, " ", 2)
-	arg := parts[0]
-	rest := ""
-	if len(parts) > 1 {
-		rest = parts[1]
-	}
-	return arg, rest
-}
-
-func parseLine(line string) (string, []string) {
-	args := make([]string, 0)
-	for arg, rest := parseArg(line); arg != ""; arg, rest = parseArg(rest) {
-		args = append(args, arg)
-	}
-	return args[0], args[1:]
-}
-
-var commands = map[string]NewMessageFunc {
-	"NICK": NewNickMessage,
-	"PING": NewPingMessage,
-	"QUIT": NewQuitMessage,
-	"USER": NewUserMessage,
-}
-
-func ParseMessage(line string) Message {
-	command, args := parseLine(line)
-	constructor := commands[command]
-	var msg Message
-	if constructor != nil {
-		msg = constructor(args)
-	}
-	if msg == nil {
-		msg = &UnknownMessage{command}
-	}
-	return msg
-}

src/irc/parse.go

@@ -0,0 +1,88 @@
+package irc
+
+import (
+	"strconv"
+	"strings"
+)
+
+func parseArg(line string) (string, string) {
+	if line == "" {
+		return "", ""
+	}
+
+	if strings.HasPrefix(line, ":") {
+		return line[1:], ""
+	}
+
+	parts := strings.SplitN(line, " ", 2)
+	arg := parts[0]
+	rest := ""
+	if len(parts) > 1 {
+		rest = parts[1]
+	}
+	return arg, rest
+}
+
+func parseLine(line string) (string, []string) {
+	args := make([]string, 0)
+	for arg, rest := parseArg(line); arg != ""; arg, rest = parseArg(rest) {
+		args = append(args, arg)
+	}
+	return args[0], args[1:]
+}
+
+var commands = map[string]func([]string) Message {
+	"NICK": NewNickMessage,
+	"PING": NewPingMessage,
+	"QUIT": NewQuitMessage,
+	"USER": NewUserMessage,
+}
+
+func ParseMessage(line string) Message {
+	command, args := parseLine(line)
+	constructor, ok := commands[command]
+	var msg Message
+	if ok {
+		msg = constructor(args)
+	}
+	if msg == nil {
+		msg = &UnknownMessage{command}
+	}
+	return msg
+}
+
+// []string => Message constructors
+
+func NewNickMessage(args []string) Message {
+	if len(args) != 1 {
+		return nil
+	}
+	return &NickMessage{args[0]}
+}
+
+func NewPingMessage(args []string) Message {
+	return &PingMessage{}
+}
+
+func NewQuitMessage(args []string) Message {
+	msg := QuitMessage{}
+	if len(args) > 0 {
+		msg.message = args[0]
+	}
+	return &msg
+}
+
+func NewUserMessage(args []string) Message {
+	if len(args) != 4 {
+		return nil
+	}
+	msg := new(UserMessage)
+	msg.user = args[0]
+	mode, err := strconv.ParseUint(args[1], 10, 8)
+	if err == nil {
+		msg.mode = uint8(mode)
+	}
+	msg.unused = args[2]
+	msg.realname = args[3]
+	return msg
+}