Safari Plugin Extension for Facebook and Twitter and Google +

I need someone who can make a Safari Extension for me. I want to be able to add the following login data ONCE: Facebook username and password Twitter username and password Google + username and password THEN, whenever i see a website i like, I want to be able to press a button in my Safari and it shares the URL to those three networks. I also would like to be able to add a comment to the post before posting too. Links need to be shortened using [login to view URL] please. Please read the project first and write the word "Understood". Also write your steps and suggestions to complete the project with a short description of what you understood.