imap: ListMessages: handle body viewing, etc

internal/store/maildir.go

@@ -2,6 +2,7 @@ package store
 
 import (
 	"errors"
+	"io"
 	"net/mail"
 	"os"
 	"path/filepath"
@@ -50,6 +51,15 @@ func (m *Maildir) NextUID() uint64 {
 	return m.uids.NextUID()
 }
 
+func (m *Maildir) MessageData(message Message) (io.ReadCloser, error) {
+	filename, err := m.filesystem.Filename(message.Key)
+	if err != nil {
+		return nil, err
+	}
+
+	return os.Open(filename)
+}
+
 func (c *concrete) CreateMaildir(m *Maildir) error {
 	if m.directory == "" {
 		m.directory = c.buildMaildirPath(m.Account, m.Name)