Social media registration and login

Dear programers, We are migrating our 18000 users from our facebook and odnoklassniki group to our website [login to view URL] It should be much easier for our users to login and register via facebook/odnoklassniki We would like to know the price and timeline for implementation of following functions: 1. Registration via facebook/odnoklassniki a. An unregistered user on the site clicks on registration b. 3 options appear for registration: usual registration via form, via facebook and odnoklassniki c. If clicked on via fb/odno then all info which the user would normally input into the registration form is fetched from the social media D. The user is redirected to the usual registration form and all the data is automatically fetched into the fields (including email used for login on social media and profile picture) - so in the end the user does not have to input data manually E. The user is promPted to fill in the missing fields d. Numbet of friends should also be fetched 2. Login A. A registered user can login either by email (even if registered via social media earlier) or social media B. If user click login via fb/odno a check is performed to see if he is registered. If he is, the user is logged in and it is not necessary to input password. c. If user is not registered, he is redirected to the registration page I hope the logic of the approach is clear. Please let me know if I can provide further info. Also if you have other ideas, please feel free to suggest a different/better approach. Kind regards, Alex