From 2e5376d7ebff114c8d5e88120db219c2e17c4dc3 Mon Sep 17 00:00:00 2001
From: Mechiel Lukkien <mechiel@ueber.net>
Date: Mon, 24 Jul 2023 08:49:19 +0200
Subject: [PATCH] when moving/copying messages in imapserve, also ensure the
 message keywords make it into the destination mailbox keywords list

---
 imapserver/server.go | 37 +++++++++++++++++++++++++++++++++----
 store/account.go     |  4 ++--
 2 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/imapserver/server.go b/imapserver/server.go
index cd8284d..595da18 100644
--- a/imapserver/server.go
+++ b/imapserver/server.go
@@ -60,6 +60,7 @@ import (
 
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promauto"
+	"golang.org/x/exp/slices"
 	"golang.org/x/text/unicode/norm"
 
 	"github.com/mjl-/bstore"
@@ -2083,6 +2084,7 @@ func (c *conn) cmdRename(tag, cmd string, p *parser) {
 					Name:        dst,
 					UIDValidity: uidval,
 					UIDNext:     1,
+					Keywords:    srcMB.Keywords,
 				}
 				err = tx.Insert(&dstMB)
 				xcheckf(err, "create new destination mailbox")
@@ -3001,8 +3003,6 @@ func (c *conn) cmdxCopy(isUID bool, tag, cmd string, p *parser) {
 			// Reserve the uids in the destination mailbox.
 			uidFirst := mbDst.UIDNext
 			mbDst.UIDNext += store.UID(len(uidargs))
-			err := tx.Update(&mbDst)
-			xcheckf(err, "reserve uid in destination mailbox")
 
 			// Fetch messages from database.
 			q := bstore.QueryTx[store.Message](tx)
@@ -3023,6 +3023,8 @@ func (c *conn) cmdxCopy(isUID bool, tag, cmd string, p *parser) {
 
 			conf, _ := c.account.Conf()
 
+			mbKeywords := map[string]struct{}{}
+
 			// Insert new messages into database.
 			var origMsgIDs, newMsgIDs []int64
 			for i, uid := range uids {
@@ -3051,6 +3053,9 @@ func (c *conn) cmdxCopy(isUID bool, tag, cmd string, p *parser) {
 				newMsgIDs = append(newMsgIDs, m.ID)
 				flags = append(flags, m.Flags)
 				keywords = append(keywords, m.Keywords)
+				for _, kw := range m.Keywords {
+					mbKeywords[kw] = struct{}{}
+				}
 
 				qmr := bstore.QueryTx[store.Recipient](tx)
 				qmr.FilterNonzero(store.Recipient{MessageID: origID})
@@ -3064,6 +3069,16 @@ func (c *conn) cmdxCopy(isUID bool, tag, cmd string, p *parser) {
 				}
 			}
 
+			// Ensure destination mailbox has keywords of the moved messages.
+			for kw := range mbKeywords {
+				if !slices.Contains(mbDst.Keywords, kw) {
+					mbDst.Keywords = append(mbDst.Keywords, kw)
+				}
+			}
+
+			err = tx.Update(&mbDst)
+			xcheckf(err, "updating destination mailbox for uids and keywords")
+
 			// Copy message files to new message ID's.
 			syncDirs := map[string]struct{}{}
 			for i := range origMsgIDs {
@@ -3146,8 +3161,6 @@ func (c *conn) cmdxMove(isUID bool, tag, cmd string, p *parser) {
 			uidFirst := mbDst.UIDNext
 			uidnext := uidFirst
 			mbDst.UIDNext += store.UID(len(uids))
-			err := tx.Update(&mbDst)
-			xcheckf(err, "reserve uids in destination mailbox")
 
 			// Update UID and MailboxID in database for messages.
 			q := bstore.QueryTx[store.Message](tx)
@@ -3161,6 +3174,8 @@ func (c *conn) cmdxMove(isUID bool, tag, cmd string, p *parser) {
 				xserverErrorf("uid and message mismatch")
 			}
 
+			keywords := map[string]struct{}{}
+
 			conf, _ := c.account.Conf()
 			for i := range msgs {
 				m := &msgs[i]
@@ -3178,8 +3193,22 @@ func (c *conn) cmdxMove(isUID bool, tag, cmd string, p *parser) {
 				uidnext++
 				err := tx.Update(m)
 				xcheckf(err, "updating moved message in database")
+
+				for _, kw := range m.Keywords {
+					keywords[kw] = struct{}{}
+				}
 			}
 
+			// Ensure destination mailbox has keywords of the moved messages.
+			for kw := range keywords {
+				if !slices.Contains(mbDst.Keywords, kw) {
+					mbDst.Keywords = append(mbDst.Keywords, kw)
+				}
+			}
+
+			err = tx.Update(&mbDst)
+			xcheckf(err, "updating destination mailbox for uids and keywords")
+
 			err = c.account.RetrainMessages(context.TODO(), c.log, tx, msgs, false)
 			xcheckf(err, "retraining messages after move")
 
diff --git a/store/account.go b/store/account.go
index e839c45..8fb821a 100644
--- a/store/account.go
+++ b/store/account.go
@@ -292,7 +292,7 @@ type Message struct {
 
 	MessageHash []byte // Hash of message. For rejects delivery, so optional like MessageID.
 	Flags
-	Keywords    []string `bstore:"index"` // Non-system or well-known $-flags. Only in "atom" syntax, stored in lower case.
+	Keywords    []string `bstore:"index"` // For keywords other than system flags or the basic well-known $-flags. Only in "atom" syntax, stored in lower case.
 	Size        int64
 	TrainedJunk *bool  // If nil, no training done yet. Otherwise, true is trained as junk, false trained as nonjunk.
 	MsgPrefix   []byte // Typically holds received headers and/or header separator.
@@ -1345,7 +1345,7 @@ func RemoveKeywords(l, remove []string) []string {
 func MergeKeywords(l, add []string) ([]string, bool) {
 	var changed bool
 	for _, k := range add {
-		if slices.Index(l, k) < 0 {
+		if !slices.Contains(l, k) {
 			l = append(l, k)
 			changed = true
 		}