Add button to delete message

Maybe we should add a confirmation step in the future.

References: https://todo.sr.ht/~sircmpwn/koushin/36

plugins/base/handlers.go

@@ -338,3 +338,44 @@ func handleMove(ectx echo.Context) error {
 
 	return ctx.Redirect(http.StatusFound, fmt.Sprintf("/mailbox/%v", to))
 }
+
+func handleDelete(ectx echo.Context) error {
+	ctx := ectx.(*koushin.Context)
+
+	mboxName, uid, err := parseMboxAndUid(ctx.Param("mbox"), ctx.Param("uid"))
+	if err != nil {
+		return echo.NewHTTPError(http.StatusBadRequest, err)
+	}
+
+	err = ctx.Session.DoIMAP(func(c *imapclient.Client) error {
+		if err := ensureMailboxSelected(c, mboxName); err != nil {
+			return err
+		}
+
+		var seqSet imap.SeqSet
+		seqSet.AddNum(uid)
+
+		item := imap.FormatFlagsOp(imap.AddFlags, true)
+		flags := []interface{}{imap.DeletedFlag}
+		if err := c.UidStore(&seqSet, item, flags, nil); err != nil {
+			return fmt.Errorf("failed to add deleted flag: %v", err)
+		}
+
+		if err := c.Expunge(nil); err != nil {
+			return fmt.Errorf("failed to expunge mailbox: %v", err)
+		}
+
+		// Deleting a message invalidates our cached message count
+		// TODO: listen to async updates instead
+		if _, err := c.Select(mboxName, false); err != nil {
+			return fmt.Errorf("failed to select mailbox: %v", err)
+		}
+
+		return nil
+	})
+	if err != nil {
+		return err
+	}
+
+	return ctx.Redirect(http.StatusFound, fmt.Sprintf("/mailbox/%v", mboxName))
+}

plugins/base/plugin.go

@@ -47,5 +47,7 @@ func init() {
 
 	p.POST("/message/:mbox/:uid/move", handleMove)
 
+	p.POST("/message/:mbox/:uid/delete", handleDelete)
+
 	koushin.RegisterPlugin(p.Plugin())
 }

plugins/base/public/message.html

@@ -26,6 +26,10 @@
 	<input type="submit" value="Move">
 </form>
 
+<form method="post" action="{{.Message.Uid}}/delete">
+	<input type="submit" value="Delete">
+</form>
+
 {{define "message-part-tree"}}
 	{{/* nested templates can't access the parent's context */}}
 	{{$ = index . 0}}