imap: use delimiter from server

To accommodate servers that use a delimiter other than "/" ("." being a
common alternative), the delimiter is fetched from the server when
connecting.

Signed-off-by: Moritz Poldrack <git@moritz.sh>
Acked-by: Robin Jarry <robin@jarry.cc>

9 files changed, 58 insertions, 18 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 53208c19..95043c45 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Colorize can style diff chunk function names with `diff_chunk_func`.
 - Warn before sending emails with an empty subject with `empty-subject-warning`
   in `aerc.conf`.
+- IMAP now uses the delimiter advertised by the server
 
 ## [0.15.2](https://git.sr.ht/~rjarry/aerc/refs/0.15.2) - 2023-05-11
 
diff --git a/widgets/dirlist.go b/widgets/dirlist.go
index da2fa69a..6a10c99a 100644
--- a/widgets/dirlist.go
+++ b/widgets/dirlist.go
@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"context"
 	"math"
-	"os"
 	"regexp"
 	"sort"
 	"time"
@@ -79,7 +78,7 @@ func NewDirectoryList(acctConf *config.AccountConfig,
 	dirlist.spinner.Start()
 
 	if uiConf.DirListTree {
-		return NewDirectoryTree(dirlist, string(os.PathSeparator))
+		return NewDirectoryTree(dirlist)
 	}
 
 	return dirlist
diff --git a/widgets/dirtree.go b/widgets/dirtree.go
index 41477c5f..c11a1fd0 100644
--- a/widgets/dirtree.go
+++ b/widgets/dirtree.go
@@ -22,16 +22,14 @@ type DirectoryTree struct {
 	listIdx int
 	list    []*types.Thread
 
-	pathSeparator string
-	treeDirs      []string
+	treeDirs []string
 }
 
-func NewDirectoryTree(dirlist *DirectoryList, pathSeparator string) DirectoryLister {
+func NewDirectoryTree(dirlist *DirectoryList) DirectoryLister {
 	dt := &DirectoryTree{
 		DirectoryList: dirlist,
 		listIdx:       -1,
 		list:          make([]*types.Thread, 0),
-		pathSeparator: pathSeparator,
 	}
 	return dt
 }
@@ -274,7 +272,7 @@ func (dt *DirectoryTree) countVisible(list []*types.Thread) (n int) {
 }
 
 func (dt *DirectoryTree) displayText(node *types.Thread) string {
-	elems := strings.Split(dt.treeDirs[getAnyUid(node)], dt.pathSeparator)
+	elems := strings.Split(dt.treeDirs[getAnyUid(node)], dt.DirectoryList.worker.PathSeparator())
 	return fmt.Sprintf("%s%s%s", threadPrefix(node, false, false), getFlag(node), elems[countLevels(node)])
 }
 
@@ -301,12 +299,12 @@ func (dt *DirectoryTree) hiddenDirectories() map[string]bool {
 	hidden := make(map[string]bool, 0)
 	for _, node := range dt.list {
 		if node.Hidden && node.FirstChild != nil {
-			elems := strings.Split(dt.treeDirs[getAnyUid(node)], dt.pathSeparator)
+			elems := strings.Split(dt.treeDirs[getAnyUid(node)], dt.DirectoryList.worker.PathSeparator())
 			if levels := countLevels(node); levels < len(elems) {
 				if node.FirstChild != nil && (levels+1) < len(elems) {
 					levels += 1
 				}
-				if dirStr := strings.Join(elems[:levels], dt.pathSeparator); dirStr != "" {
+				if dirStr := strings.Join(elems[:levels], dt.DirectoryList.worker.PathSeparator()); dirStr != "" {
 					hidden[dirStr] = true
 				}
 			}
@@ -317,12 +315,12 @@ func (dt *DirectoryTree) hiddenDirectories() map[string]bool {
 
 func (dt *DirectoryTree) setHiddenDirectories(hiddenDirs map[string]bool) {
 	for _, node := range dt.list {
-		elems := strings.Split(dt.treeDirs[getAnyUid(node)], dt.pathSeparator)
+		elems := strings.Split(dt.treeDirs[getAnyUid(node)], dt.DirectoryList.worker.PathSeparator())
 		if levels := countLevels(node); levels < len(elems) {
 			if node.FirstChild != nil && (levels+1) < len(elems) {
 				levels += 1
 			}
-			strDir := strings.Join(elems[:levels], dt.pathSeparator)
+			strDir := strings.Join(elems[:levels], dt.DirectoryList.worker.PathSeparator())
 			if hidden, ok := hiddenDirs[strDir]; hidden && ok {
 				node.Hidden = true
 			}
@@ -340,7 +338,7 @@ func (dt *DirectoryTree) buildTree() {
 
 	sTree := make([][]string, 0)
 	for i, dir := range dt.dirs {
-		elems := strings.Split(dir, dt.pathSeparator)
+		elems := strings.Split(dir, dt.DirectoryList.worker.PathSeparator())
 		if len(elems) == 0 {
 			continue
 		}
@@ -364,7 +362,7 @@ func (dt *DirectoryTree) buildTree() {
 	// folders-sort
 	if dt.DirectoryList.acctConf.EnableFoldersSort {
 		toStr := func(t *types.Thread) string {
-			if elems := strings.Split(dt.treeDirs[getAnyUid(t)], dt.pathSeparator); len(elems) > 0 {
+			if elems := strings.Split(dt.treeDirs[getAnyUid(t)], dt.DirectoryList.worker.PathSeparator()); len(elems) > 0 {
 				return elems[0]
 			}
 			return ""
diff --git a/worker/imap/connect.go b/worker/imap/connect.go
index 6f341753..f0ed8043 100644
--- a/worker/imap/connect.go
+++ b/worker/imap/connect.go
@@ -94,6 +94,17 @@ func (w *IMAPWorker) connect() (*client.Client, error) {
 		return nil, err
 	}
 
+	info := make(chan *imap.MailboxInfo, 1)
+	if err := c.List("", "", info); err != nil {
+		return nil, fmt.Errorf("failed to retrieve delimiter: %w", err)
+	}
+	mailboxinfo := <-info
+	w.delimiter = mailboxinfo.Delimiter
+	if w.delimiter == "" {
+		// just in case some implementation does not follow standards
+		w.delimiter = "/"
+	}
+
 	return c, nil
 }
 
diff --git a/worker/imap/worker.go b/worker/imap/worker.go
index 1f61f458..f9a722e6 100644
--- a/worker/imap/worker.go
+++ b/worker/imap/worker.go
@@ -61,11 +61,12 @@ type imapConfig struct {
 type IMAPWorker struct {
 	config imapConfig
 
-	client   *imapClient
-	selected *imap.MailboxStatus
-	updates  chan client.Update
-	worker   *types.Worker
-	seqMap   SeqMap
+	client    *imapClient
+	selected  *imap.MailboxStatus
+	updates   chan client.Update
+	worker    *types.Worker
+	seqMap    SeqMap
+	delimiter string
 
 	idler    *idler
 	observer *observer
@@ -311,3 +312,10 @@ func (w *IMAPWorker) Run() {
 func (w *IMAPWorker) Capabilities() *models.Capabilities {
 	return w.caps
 }
+
+func (w *IMAPWorker) PathSeparator() string {
+	if w.delimiter == "" {
+		return "/"
+	}
+	return w.delimiter
+}
diff --git a/worker/maildir/worker.go b/worker/maildir/worker.go
index ba72432c..b222aab8 100644
--- a/worker/maildir/worker.go
+++ b/worker/maildir/worker.go
@@ -108,6 +108,13 @@ func (w *Worker) Capabilities() *models.Capabilities {
 	return w.capabilities
 }
 
+func (w *Worker) PathSeparator() string {
+	if w.maildirpp {
+		return "."
+	}
+	return string(os.PathSeparator)
+}
+
 func (w *Worker) handleAction(action types.WorkerMessage) {
 	msg := w.worker.ProcessAction(action)
 	switch msg := msg.(type) {
diff --git a/worker/mbox/worker.go b/worker/mbox/worker.go
index fbdbec36..47713048 100644
--- a/worker/mbox/worker.go
+++ b/worker/mbox/worker.go
@@ -383,6 +383,10 @@ func (w *mboxWorker) Capabilities() *models.Capabilities {
 	return w.capabilities
 }
 
+func (w *mboxWorker) PathSeparator() string {
+	return "/"
+}
+
 func filterUids(folder *container, uids []uint32, args []string) ([]uint32, error) {
 	criteria, err := lib.GetSearchCriteria(args)
 	if err != nil {
diff --git a/worker/notmuch/worker.go b/worker/notmuch/worker.go
index 6b1b64d9..d5c012ad 100644
--- a/worker/notmuch/worker.go
+++ b/worker/notmuch/worker.go
@@ -109,6 +109,13 @@ func (w *worker) Capabilities() *models.Capabilities {
 	return w.capabilities
 }
 
+func (w *worker) PathSeparator() string {
+	// make it configurable?
+	// <rockorager> You can use those in query maps to force a tree
+	// <rockorager> Might be nice to be configurable? I see some notmuch people namespace with "::"
+	return "/"
+}
+
 func (w *worker) done(msg types.WorkerMessage) {
 	w.w.PostMessage(&types.Done{Message: types.RespondTo(msg)}, nil)
 }
diff --git a/worker/types/worker.go b/worker/types/worker.go
index 55e00faf..7033bf77 100644
--- a/worker/types/worker.go
+++ b/worker/types/worker.go
@@ -15,6 +15,7 @@ var lastId int64 = 1 // access via atomic
 type Backend interface {
 	Run()
 	Capabilities() *models.Capabilities
+	PathSeparator() string
 }
 
 type Worker struct {
@@ -179,3 +180,7 @@ func (worker *Worker) PostMessageInfoError(msg WorkerMessage, uid uint32, err er
 		Message: RespondTo(msg),
 	}, nil)
 }
+
+func (worker *Worker) PathSeparator() string {
+	return worker.Backend.PathSeparator()
+}