Develop a Mac Application

Want to develop a software which would be able to import designer's file developed by using photoshop or illustrator or sketch and check the css details of it. Also need the login panel which would be connected through database online so no fraudulent case will come. Without login and internet connectivity user would not be able to use software. Software should work like creative cloud. Also want to add the functionality of sharing the file with another user using email id so with that email id when another user logs in they would be able to imported files.