Separated read-only channels

category.go

@@ -59,7 +59,12 @@ func (c *Category) Servers(container cchat.ServersContainer) error {
 
 	var chv = make([]cchat.Server, len(chs))
 	for i := range chs {
-		chv[i] = NewChannel(c.session, chs[i])
+		c, err := NewChannel(c.session, chs[i])
+		if err != nil {
+			return errors.Wrapf(err, "Failed to make channel %s: %v", chs[i].Name, err)
+		}
+
+		chv[i] = c
 	}
 
 	container.SetServers(chv)

channel.go

@@ -5,7 +5,6 @@ import (
 	"sort"
 	"time"
 
-	"github.com/diamondburned/arikawa/api"
 	"github.com/diamondburned/arikawa/discord"
 	"github.com/diamondburned/arikawa/gateway"
 	"github.com/diamondburned/cchat"
@@ -69,9 +68,6 @@ type Channel struct {
 var (
 	_ cchat.Server                       = (*Channel)(nil)
 	_ cchat.ServerMessage                = (*Channel)(nil)
-	_ cchat.ServerMessageSender           = (*Channel)(nil)
-	_ cchat.ServerMessageAttachmentSender = (*Channel)(nil)
-	_ cchat.ServerMessageSendCompleter    = (*Channel)(nil)
 	_ cchat.ServerNickname               = (*Channel)(nil)
 	_ cchat.ServerMessageEditor          = (*Channel)(nil)
 	_ cchat.ServerMessageActioner        = (*Channel)(nil)
@@ -79,7 +75,22 @@ var (
 	_ cchat.ServerMessageUnreadIndicator = (*Channel)(nil)
 )
 
-func NewChannel(s *Session, ch discord.Channel) *Channel {
+func NewChannel(s *Session, ch discord.Channel) (cchat.Server, error) {
+	p, err := s.Permissions(ch.ID, s.userID)
+	if err != nil {
+		return nil, errors.Wrap(err, "Failed to get permission")
+	}
+
+	var channel = NewROChannel(s, ch)
+	if p.Has(discord.PermissionSendMessages) {
+		return NewSendableChannel(channel), nil
+	}
+	return channel, nil
+}
+
+// NewROChannel creates a new read-only channel. This function is mainly used
+// internally.
+func NewROChannel(s *Session, ch discord.Channel) *Channel {
 	return &Channel{
 		id:      ch.ID,
 		guildID: ch.GuildID,
@@ -276,37 +287,6 @@ func (ch *Channel) JoinServer(ctx context.Context, ct cchat.MessagesContainer) (
 	return joinCancels(addcancel()), nil
 }
 
-func (ch *Channel) SendMessage(msg cchat.SendableMessage) error {
-	var send = api.SendMessageData{Content: msg.Content()}
-	if noncer, ok := msg.(cchat.MessageNonce); ok {
-		send.Nonce = noncer.Nonce()
-	}
-	if attcher, ok := msg.(cchat.SendableMessageAttachments); ok {
-		send.Files = addAttachments(attcher.Attachments())
-	}
-
-	_, err := ch.session.SendMessageComplex(ch.id, send)
-	return err
-}
-
-func (ch *Channel) SendAttachments(atts []cchat.MessageAttachment) error {
-	_, err := ch.session.SendMessageComplex(ch.id, api.SendMessageData{
-		Files: addAttachments(atts),
-	})
-	return err
-}
-
-func addAttachments(atts []cchat.MessageAttachment) []api.SendMessageFile {
-	var files = make([]api.SendMessageFile, len(atts))
-	for i, a := range atts {
-		files[i] = api.SendMessageFile{
-			Name:   a.Name,
-			Reader: a,
-		}
-	}
-	return files
-}
-
 // MessageEditable returns true if the given message ID belongs to the current
 // user.
 func (ch *Channel) MessageEditable(id string) bool {
@@ -434,29 +414,6 @@ func (ch *Channel) canManageMessages(userID discord.Snowflake) bool {
 	return p.Has(discord.PermissionManageMessages)
 }
 
-// CompleteMessage implements message input completion capability for Discord.
-// This method supports user mentions, channel mentions and emojis.
-//
-// For the individual implementations, refer to channel_completion.go.
-func (ch *Channel) CompleteMessage(words []string, i int) (entries []cchat.CompletionEntry) {
-	var word = words[i]
-	// Word should have at least a character for the char check.
-	if len(word) < 1 {
-		return
-	}
-
-	switch word[0] {
-	case '@':
-		return ch.completeMentions(word[1:])
-	case '#':
-		return ch.completeChannels(word[1:])
-	case ':':
-		return ch.completeEmojis(word[1:])
-	}
-
-	return
-}
-
 func (ch *Channel) Typing() error {
 	return ch.session.Typing(ch.id)
 }

channel_completion.go

@@ -32,7 +32,7 @@ func completionUserEntry(s *Session, u discord.User, g *discord.Guild) cchat.Com
 	}
 }
 
-func (ch *Channel) completeMentions(word string) (entries []cchat.CompletionEntry) {
+func (ch *SendableChannel) completeMentions(word string) (entries []cchat.CompletionEntry) {
 	// If there is no input, then we should grab the latest messages.
 	if word == "" {
 		msgs, _ := ch.messages()
@@ -120,7 +120,7 @@ func (ch *Channel) completeMentions(word string) (entries []cchat.CompletionEntr
 	return
 }
 
-func (ch *Channel) completeChannels(word string) (entries []cchat.CompletionEntry) {
+func (ch *SendableChannel) completeChannels(word string) (entries []cchat.CompletionEntry) {
 	// Ignore if empty word.
 	if word == "" {
 		return
@@ -164,7 +164,7 @@ func (ch *Channel) completeChannels(word string) (entries []cchat.CompletionEntr
 	return
 }
 
-func (ch *Channel) completeEmojis(word string) (entries []cchat.CompletionEntry) {
+func (ch *SendableChannel) completeEmojis(word string) (entries []cchat.CompletionEntry) {
 	// Ignore if empty word.
 	if word == "" {
 		return

channel_memberlist.go

@@ -0,0 +1 @@
+package discord

channel_send.go

@@ -0,0 +1,76 @@
+package discord
+
+import (
+	"github.com/diamondburned/arikawa/api"
+	"github.com/diamondburned/cchat"
+)
+
+type SendableChannel struct {
+	Channel
+}
+
+// NewSendableChannel creates a sendable channel. This function is mainly used
+// internally
+func NewSendableChannel(ch *Channel) *SendableChannel {
+	return &SendableChannel{*ch}
+}
+
+var (
+	_ cchat.ServerMessageSender           = (*SendableChannel)(nil)
+	_ cchat.ServerMessageSendCompleter    = (*SendableChannel)(nil)
+	_ cchat.ServerMessageAttachmentSender = (*SendableChannel)(nil)
+)
+
+func (ch *SendableChannel) SendMessage(msg cchat.SendableMessage) error {
+	var send = api.SendMessageData{Content: msg.Content()}
+	if noncer, ok := msg.(cchat.MessageNonce); ok {
+		send.Nonce = noncer.Nonce()
+	}
+	if attcher, ok := msg.(cchat.SendableMessageAttachments); ok {
+		send.Files = addAttachments(attcher.Attachments())
+	}
+
+	_, err := ch.session.SendMessageComplex(ch.id, send)
+	return err
+}
+
+func (ch *SendableChannel) SendAttachments(atts []cchat.MessageAttachment) error {
+	_, err := ch.session.SendMessageComplex(ch.id, api.SendMessageData{
+		Files: addAttachments(atts),
+	})
+	return err
+}
+
+func addAttachments(atts []cchat.MessageAttachment) []api.SendMessageFile {
+	var files = make([]api.SendMessageFile, len(atts))
+	for i, a := range atts {
+		files[i] = api.SendMessageFile{
+			Name:   a.Name,
+			Reader: a,
+		}
+	}
+	return files
+}
+
+// CompleteMessage implements message input completion capability for Discord.
+// This method supports user mentions, channel mentions and emojis.
+//
+// For the individual implementations, refer to channel_completion.go.
+func (ch *SendableChannel) CompleteMessage(words []string, i int) (entries []cchat.CompletionEntry) {
+	var word = words[i]
+	// Word should have at least a character for the char check.
+	if len(word) < 1 {
+		return
+	}
+
+	switch word[0] {
+	case '@':
+		return ch.completeMentions(word[1:])
+	case '#':
+		return ch.completeChannels(word[1:])
+	case ':':
+		return ch.completeEmojis(word[1:])
+	}
+
+	return
+}

guild.go

@@ -175,7 +175,11 @@ func (g *Guild) Servers(container cchat.ServersContainer) error {
 		case discord.GuildCategory:
 			chs = append(chs, NewCategory(g.session, ch))
 		case discord.GuildText:
-			chs = append(chs, NewChannel(g.session, ch))
+			c, err := NewChannel(g.session, ch)
+			if err != nil {
+				return errors.Wrapf(err, "Failed to make channel %q: %v", ch.Name, err)
+			}
+			chs = append(chs, c)
 		}
 	}