Add notifications package for easy sending of notifications (#779)

Co-authored-by: kolaente <k@knt.li>
Reviewed-on: https://kolaente.dev/vikunja/api/pulls/779
Co-authored-by: konrad <konrad@kola-entertainments.de>
Co-committed-by: konrad <konrad@kola-entertainments.de>

pkg/models/notifications.go

@@ -0,0 +1,47 @@
+// Vikunja is a to-do list application to facilitate your life.
+// Copyright 2018-2021 Vikunja and contributors. All rights reserved.
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public Licensee as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public Licensee for more details.
+//
+// You should have received a copy of the GNU Affero General Public Licensee
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package models
+
+import (
+	"strconv"
+
+	"code.vikunja.io/api/pkg/config"
+	"code.vikunja.io/api/pkg/notifications"
+	"code.vikunja.io/api/pkg/user"
+)
+
+// ReminderDueNotification represents a ReminderDueNotification notification
+type ReminderDueNotification struct {
+	User *user.User
+	Task *Task
+}
+
+// ToMail returns the mail notification for ReminderDueNotification
+func (n *ReminderDueNotification) ToMail() *notifications.Mail {
+	return notifications.NewMail().
+		To(n.User.Email).
+		Subject(`Reminder for "`+n.Task.Title+`"`).
+		Greeting("Hi "+n.User.GetName()+",").
+		Line(`This is a friendly reminder of the task "`+n.Task.Title+`".`).
+		Action("Open Task", config.ServiceFrontendurl.GetString()+"tasks/"+strconv.FormatInt(n.Task.ID, 10)).
+		Line("Have a nice day!")
+}
+
+// ToDB returns the ReminderDueNotification notification in a format which can be saved in the db
+func (n *ReminderDueNotification) ToDB() interface{} {
+	return nil
+}