From d6b6a5dc4484be7598baa666828ec7962c6bebdf Mon Sep 17 00:00:00 2001
From: Aine <aine@etke.cc>
Date: Tue, 4 Oct 2022 21:45:52 +0300
Subject: [PATCH] add catch-all mailbox, closes #25

---
 README.md            |  1 +
 bot/command.go       |  8 ++++++++
 bot/command_admin.go | 38 ++++++++++++++++++++++++++++++++++++++
 bot/email.go         | 18 ++++++++++++++++--
 bot/settings_bot.go  |  6 ++++++
 5 files changed, 69 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 2a5a697..6183af3 100644
--- a/README.md
+++ b/README.md
@@ -253,6 +253,7 @@ If you want to change them - check available options in the help message (`!pm h
 ---
 
 * **!pm dkim** - Get DKIM signature
+* **!pm catch-all** - Configure catch-all mailbox
 * **!pm users** - Get or set allowed users patterns
 * **!pm mailboxes** - Show the list of all mailboxes
 * **!pm delete** &lt;mailbox&gt; - Delete specific mailbox
diff --git a/bot/command.go b/bot/command.go
index 61003df..d933775 100644
--- a/bot/command.go
+++ b/bot/command.go
@@ -17,6 +17,7 @@ const (
 	commandStop      = "stop"
 	commandSend      = "send"
 	commandDKIM      = "dkim"
+	commandCatchAll  = botOptionCatchAll
 	commandUsers     = botOptionUsers
 	commandDelete    = "delete"
 	commandMailboxes = "mailboxes"
@@ -144,6 +145,11 @@ func (b *Bot) initCommands() commandList {
 			description: "Get DKIM signature",
 			allowed:     b.allowAdmin,
 		},
+		{
+			key:         commandCatchAll,
+			description: "Get or set catch-all mailbox",
+			allowed:     b.allowAdmin,
+		},
 		{
 			key:         commandMailboxes,
 			description: "Show the list of all mailboxes",
@@ -184,6 +190,8 @@ func (b *Bot) handleCommand(ctx context.Context, evt *event.Event, commandSlice
 		b.runDKIM(ctx, commandSlice)
 	case commandUsers:
 		b.runUsers(ctx, commandSlice)
+	case commandCatchAll:
+		b.runCatchAll(ctx, commandSlice)
 	case commandDelete:
 		b.runDelete(ctx, commandSlice)
 	case commandMailboxes:
diff --git a/bot/command_admin.go b/bot/command_admin.go
index 22f9e63..89dbd0e 100644
--- a/bot/command_admin.go
+++ b/bot/command_admin.go
@@ -166,3 +166,41 @@ func (b *Bot) runDKIM(ctx context.Context, commandSlice []string) {
 			"To reset the signature, send `%s dkim reset`",
 		signature, signature, b.prefix))
 }
+
+func (b *Bot) runCatchAll(ctx context.Context, commandSlice []string) {
+	evt := eventFromContext(ctx)
+	cfg := b.getBotSettings()
+	if len(commandSlice) < 2 {
+		var msg strings.Builder
+		msg.WriteString("Currently: `")
+		if cfg.CatchAll() != "" {
+			msg.WriteString(cfg.CatchAll())
+		} else {
+			msg.WriteString("not set")
+		}
+		msg.WriteString("`\n\n")
+		msg.WriteString("Usage: `")
+		msg.WriteString(b.prefix)
+		msg.WriteString(" catch-all MAILBOX`")
+		msg.WriteString("where mailbox is valid and existing mailbox name\n")
+
+		b.SendNotice(ctx, evt.RoomID, msg.String())
+		return
+	}
+
+	mailbox := utils.Mailbox(commandSlice[1])
+	_, ok := b.GetMapping(mailbox)
+	if !ok {
+		b.SendError(ctx, evt.RoomID, "mailbox does not exist, kupo.")
+		return
+	}
+
+	cfg.Set(botOptionCatchAll, mailbox)
+	err := b.setBotSettings(cfg)
+	if err != nil {
+		b.Error(ctx, evt.RoomID, "cannot save bot options: %v", err)
+		return
+	}
+
+	b.SendNotice(ctx, evt.RoomID, fmt.Sprintf("Catch-all is set to: `%s@%s`.", mailbox, b.domain))
+}
diff --git a/bot/email.go b/bot/email.go
index 6418215..b946795 100644
--- a/bot/email.go
+++ b/bot/email.go
@@ -31,12 +31,12 @@ func (b *Bot) SetMTA(mta utils.MTA) {
 	b.mta = mta
 }
 
-// GetMapping returns mapping of mailbox = room
-func (b *Bot) GetMapping(mailbox string) (id.RoomID, bool) {
+func (b *Bot) getMapping(mailbox string) (id.RoomID, bool) {
 	v, ok := b.rooms.Load(mailbox)
 	if !ok {
 		return "", ok
 	}
+
 	roomID, ok := v.(id.RoomID)
 	if !ok {
 		return "", ok
@@ -45,6 +45,20 @@ func (b *Bot) GetMapping(mailbox string) (id.RoomID, bool) {
 	return roomID, ok
 }
 
+// GetMapping returns mapping of mailbox = room
+func (b *Bot) GetMapping(mailbox string) (id.RoomID, bool) {
+	roomID, ok := b.getMapping(mailbox)
+	if !ok {
+		catchAll := b.getBotSettings().CatchAll()
+		if catchAll == "" {
+			return roomID, ok
+		}
+		return b.getMapping(catchAll)
+	}
+
+	return roomID, ok
+}
+
 // Send email to matrix room
 func (b *Bot) Send2Matrix(ctx context.Context, email *utils.Email, incoming bool) error {
 	roomID, ok := b.GetMapping(email.Mailbox(incoming))
diff --git a/bot/settings_bot.go b/bot/settings_bot.go
index 94fa98e..269d6d0 100644
--- a/bot/settings_bot.go
+++ b/bot/settings_bot.go
@@ -12,6 +12,7 @@ const acBotSettingsKey = "cc.etke.postmoogle.config"
 // bot options keys
 const (
 	botOptionUsers          = "users"
+	botOptionCatchAll       = "catch-all"
 	botOptionDKIMSignature  = "dkim.pub"
 	botOptionDKIMPrivateKey = "dkim.pem"
 )
@@ -42,6 +43,11 @@ func (s botSettings) Users() []string {
 	return []string{value}
 }
 
+// CatchAll option
+func (s botSettings) CatchAll() string {
+	return s.Get(botOptionCatchAll)
+}
+
 // DKIMSignature (DNS TXT record)
 func (s botSettings) DKIMSignature() string {
 	return s.Get(botOptionDKIMSignature)