Asterisk GURU to create a browser based call answering application

Small telephone answering service has created a custom web based operator panel which we will use for our agents to answer incoming calls routed via DID and Caller ID. Each DID and Caller ID associated with each company has their own customized greeting so we will know how to answer the phone appropriately. The situation is our web panel is simply a website with a database at this point. We need a asterisk developer that can create an inbuilt softphone into our web application so that we can use the credentials of our PBXTRA phone extensions to login to the panel and receive, transfer, hold and conference calls coming in. This application should be scalable to eventually work with softphones, deskphones, etc . On our web based panel we have buttons for answer, dial, transfer, hold, conference, park, mute, etc. We need these buttons to work in such away that we can control the call from our desktop alone with headsets. There is an admin interface where we enter new customers in and this is where we associate the company with their assigned DID etc. We control the flow of calls from our Fonality PBXTRA system which should then be routed to our operator panel for call answering. Please only apply if you have extensive experience in creating applications such as HUD, HUD Light, Flash Operator Panel, Isymphony etc. Please list all experience you have and the best way to accomplish our goal.