Add additional flagging functionality

More mail flags can now be set, unset, and toggled, not just the
read/seen flag.

This functionality is implemented with a new `:flag` and `:unflag`
command, which are extensions to the matching `:read` and `:unread`
commands, adding support for different flags.  In fact, the
`read`/`unread` commands are now recognized aliases to `flag`/`unflag`.
The new commands are also well documented in aerc(1).

The change mostly extends the previous read/unread setting functionality
by adding a selection for the flag to change.

1 files changed, 11 insertions, 25 deletions

diff --git a/worker/maildir/message.go b/worker/maildir/message.go
index 5c6c930..55e2613 100644
--- a/worker/maildir/message.go
+++ b/worker/maildir/message.go
@@ -53,43 +53,29 @@ func (m Message) SetFlags(flags []maildir.Flag) error {
 	return m.dir.SetFlags(m.key, flags)
 }
 
-// MarkReplied either adds or removes the maildir.FlagReplied flag from the
-// message.
-func (m Message) MarkReplied(answered bool) error {
+// SetOneFlag enables or disables a single message flag on the message.
+func (m Message) SetOneFlag(flag maildir.Flag, enable bool) error {
 	flags, err := m.Flags()
 	if err != nil {
 		return fmt.Errorf("could not read previous flags: %v", err)
 	}
-	if answered {
-		flags = append(flags, maildir.FlagReplied)
+	if enable {
+		flags = append(flags, flag)
 		return m.SetFlags(flags)
 	}
 	var newFlags []maildir.Flag
-	for _, flag := range flags {
-		if flag != maildir.FlagReplied {
-			newFlags = append(newFlags, flag)
+	for _, oldFlag := range flags {
+		if oldFlag != flag {
+			newFlags = append(newFlags, oldFlag)
 		}
 	}
 	return m.SetFlags(newFlags)
 }
 
-// MarkRead either adds or removes the maildir.FlagSeen flag from the message.
-func (m Message) MarkRead(seen bool) error {
-	flags, err := m.Flags()
-	if err != nil {
-		return fmt.Errorf("could not read previous flags: %v", err)
-	}
-	if seen {
-		flags = append(flags, maildir.FlagSeen)
-		return m.SetFlags(flags)
-	}
-	var newFlags []maildir.Flag
-	for _, flag := range flags {
-		if flag != maildir.FlagSeen {
-			newFlags = append(newFlags, flag)
-		}
-	}
-	return m.SetFlags(newFlags)
+// MarkReplied either adds or removes the maildir.FlagReplied flag from the
+// message.
+func (m Message) MarkReplied(answered bool) error {
+	return m.SetOneFlag(maildir.FlagReplied, answered)
 }
 
 // Remove deletes the email immediately.