Progress, most of this probably doesnt work.

chat/channel.go

@@ -1,5 +1,7 @@
 package chat
 
+import "fmt"
+
 const historyLen = 20
 
 // Channel definition, also a Set of User Items
@@ -8,13 +10,13 @@ type Channel struct {
 	topic     string
 	history   *History
 	users     *Set
-	out     chan<- Message
+	broadcast chan<- Message
 }
 
-func NewChannel(id string, out chan<- Message) *Channel {
+func NewChannel(id string, broadcast chan<- Message) *Channel {
 	ch := Channel{
 		id:        id,
-		out:     out,
+		broadcast: broadcast,
 		history:   NewHistory(historyLen),
 		users:     NewSet(),
 	}
@@ -22,16 +24,24 @@ func NewChannel(id string, out chan<- Message) *Channel {
 }
 
 func (ch *Channel) Send(m Message) {
-	ch.out <- m
+	ch.broadcast <- m
 }
 
 func (ch *Channel) Join(u *User) error {
 	err := ch.users.Add(u)
+	if err != nil {
+		s := fmt.Sprintf("%s joined. (Connected: %d)", u.Name(), ch.users.Len())
+		ch.Send(*NewMessage(s))
+	}
 	return err
 }
 
 func (ch *Channel) Leave(u *User) error {
 	err := ch.users.Remove(u)
+	if err != nil {
+		s := fmt.Sprintf("%s left.", u.Name())
+		ch.Send(*NewMessage(s))
+	}
 	return err
 }
 

chat/channel_test.go

@@ -0,0 +1,27 @@
+package chat
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestChannel(t *testing.T) {
+	s := &MockScreen{}
+	out := make(chan Message)
+	defer close(out)
+
+	go func() {
+		for msg := range out {
+			s.Write([]byte(msg.Render(nil)))
+		}
+	}()
+
+	u := NewUser("foo", s)
+	ch := NewChannel("", out)
+	ch.Join(u)
+
+	expected := []byte(" * foo joined. (Connected: 1)")
+	if !reflect.DeepEqual(s.received, expected) {
+		t.Errorf("Got: %s, Expected: %s", s.received, expected)
+	}
+}

chat/command.go

@@ -0,0 +1,52 @@
+package chat
+
+import (
+	"errors"
+	"strings"
+)
+
+var ErrInvalidCommand error = errors.New("invalid command")
+var ErrNoOwner error = errors.New("command without owner")
+
+type CmdHandler func(host Host, msg Message, args []string) error
+
+type Commands map[string]CmdHandler
+
+// Register command
+func (c Commands) Add(cmd string, handler CmdHandler) {
+	c[cmd] = handler
+}
+
+// Execute command message, assumes IsCommand was checked
+func (c Commands) Run(host Host, msg Message) error {
+	if msg.from == nil {
+		return ErrNoOwner
+	}
+
+	cmd, args := msg.ParseCommand()
+	handler, ok := c[cmd]
+	if !ok {
+		return ErrInvalidCommand
+	}
+
+	return handler(host, msg, args)
+}
+
+var defaultCmdHandlers Commands
+
+func init() {
+	c := Commands{}
+
+	c.Add("me", func(host Host, msg Message, args []string) error {
+		me := strings.TrimLeft(msg.Body, "/me")
+		if me == "" {
+			me = " is at a loss for words."
+		}
+
+		// XXX: Finish this.
+
+		return nil
+	})
+
+	defaultCmdHandlers = c
+}

chat/host.go

@@ -0,0 +1,43 @@
+package chat
+
+const messageBuffer = 20
+
+// Host knows about all the commands and channels.
+type Host struct {
+	defaultChannel *Channel
+	commands       Commands
+	done           chan struct{}
+}
+
+func NewHost() *Host {
+	h := Host{
+		commands: defaultCmdHandlers,
+	}
+	h.defaultChannel = h.CreateChannel("")
+	return &h
+}
+
+func (h *Host) handleCommand(m Message) {
+	// TODO: ...
+}
+
+func (h *Host) broadcast(ch *Channel, m Message) {
+	// TODO: ...
+}
+
+func (h *Host) CreateChannel(id string) *Channel {
+	out := make(chan Message, 20)
+	ch := NewChannel(id, out)
+
+	go func() {
+		for msg := range out {
+			if msg.IsCommand() {
+				go h.handleCommand(msg)
+				continue
+			}
+			h.broadcast(ch, msg)
+		}
+	}()
+
+	return ch
+}

chat/message.go

@@ -2,6 +2,7 @@ package chat
 
 import (
 	"fmt"
+	"strings"
 	"time"
 )
 
@@ -14,10 +15,9 @@ type Message struct {
 	themeCache *map[*Theme]string
 }
 
-func NewMessage(from *User, body string) *Message {
+func NewMessage(body string) *Message {
 	m := Message{
 		Body:      body,
-		from:      from,
 		timestamp: time.Now(),
 	}
 	return &m
@@ -37,19 +37,35 @@ func (m *Message) From(u *User) *Message {
 
 // Render message based on the given theme
 func (m *Message) Render(*Theme) string {
-	// TODO: Render based on theme.
+	// TODO: Render based on theme
 	// TODO: Cache based on theme
 	var msg string
-	if m.to != nil {
+	if m.to != nil && m.from != nil {
-		msg = fmt.Sprintf("[PM from %s] %s", m.to, m.Body)
+		msg = fmt.Sprintf("[PM from %s] %s", m.from, m.Body)
 	} else if m.from != nil {
 		msg = fmt.Sprintf("%s: %s", m.from, m.Body)
+	} else if m.to != nil {
+		msg = fmt.Sprintf("-> %s", m.Body)
 	} else {
 		msg = fmt.Sprintf(" * %s", m.Body)
 	}
 	return msg
 }
 
+// Render message without a theme
 func (m *Message) String() string {
 	return m.Render(nil)
 }
+
+// Wether message is a command (starts with /)
+func (m *Message) IsCommand() bool {
+	return strings.HasPrefix(m.Body, "/")
+}
+
+// Parse command (assumes IsCommand was already called)
+func (m *Message) ParseCommand() (string, []string) {
+	// TODO: Tokenize this properly, to support quoted args?
+	cmd := strings.Split(m.Body, " ")
+	args := cmd[1:]
+	return cmd[0][1:], args
+}

chat/set_test.go

@@ -5,7 +5,7 @@ import "testing"
 func TestSet(t *testing.T) {
 	var err error
 	s := NewSet()
-	u := NewUser("foo")
+	u := NewUser("foo", nil)
 
 	if s.In(u) {
 		t.Errorf("Set should be empty.")
@@ -20,7 +20,7 @@ func TestSet(t *testing.T) {
 		t.Errorf("Set should contain user.")
 	}
 
-	u2 := NewUser("bar")
+	u2 := NewUser("bar", nil)
 	err = s.Add(u2)
 	if err != nil {
 		t.Error(err)

chat/user.go

@@ -1,21 +1,27 @@
 package chat
 
 import (
+	"io"
 	"math/rand"
 	"time"
 )
 
-// User definition, implemented set Item interface
+// User definition, implemented set Item interface and io.Writer
 type User struct {
 	name     string
 	op       bool
 	colorIdx int
 	joined   time.Time
+	screen   io.Writer
 	Config   UserConfig
 }
 
-func NewUser(name string) *User {
+func NewUser(name string, screen io.Writer) *User {
-	u := User{Config: *DefaultUserConfig}
+	u := User{
+		screen: screen,
+		joined: time.Now(),
+		Config: *DefaultUserConfig,
+	}
 	u.SetName(name)
 	return &u
 }
@@ -46,6 +52,11 @@ func (u *User) SetOp(op bool) {
 	u.op = op
 }
 
+// Write to user's screen
+func (u *User) Write(p []byte) (n int, err error) {
+	return u.screen.Write(p)
+}
+
 // Container for per-user configurations.
 type UserConfig struct {
 	Highlight bool

chat/user_test.go

@@ -0,0 +1,26 @@
+package chat
+
+import (
+	"reflect"
+	"testing"
+)
+
+type MockScreen struct {
+	received []byte
+}
+
+func (s *MockScreen) Write(data []byte) (n int, err error) {
+	s.received = append(s.received, data...)
+	return len(data), nil
+}
+
+func TestMakeUser(t *testing.T) {
+	s := &MockScreen{}
+	u := NewUser("foo", s)
+
+	line := []byte("hello")
+	u.Write(line)
+	if !reflect.DeepEqual(s.received, line) {
+		t.Errorf("Expected hello but got: %s", s.received)
+	}
+}