OAuth with ADFS 2.0 in existing Web API

You could use CSOM or simply RESTful API where it will require the user authorization over web. Once authorized, extract the token for passing any request to office365. Relevant Skills and Experience Let me know what function you need to process once user authenticated. And what scripting language you are using.

Hi I am .NET Developer and I have 2+ years of experience developing variety of applications. I have seen your project and I am interested in developing in it. I can develop it for you in very less budget and time. Feel free to send me a message to discuss any details. Thanks

Would you be able to provide a little more detail? I have experience architecting, implementing and running ADFS. I've federated several O365 tenants with ADFS as well as implemented SSO between ADFS and various cloud and on-prem applications. If you would like my assistance, I'd be happy to help. Thanks- Jason