Facebook page to share the video and then display custom text message at the end of the video

I am developing a facebook app with facebook api. I need the feature to share the video however at the end of the video I need to display a custom message. This message with change everytime and will be some thing that user will post on the wall. Please advice if this is possible. If yes then please share your thoughts. I have tried the api however could not find an api which allows to create videos run time or embed text to the video. Please help