Initate a teams call from external application

Hello,

I have a CRM system written in WPF which runs on the same computer as the Microsoft Teams Application. I would like to implement Teams calling in my application in a simple manner. A button in my WPF application which when pressed would start teams dialing the recipient (ultimately could be a teams to teams call or teams to PSTN if the environment has been set up). I have looked at many examples but am still stumped by the approach.

I have seen the incidentbot on github but this requires a meeting to be setup, and in addition, the 'bot' is part of the meeting. All I am trying to do is do a 1-1 call without the system dialing me and the recipient into a meeting. Effectively just like me selecting the recipient in teams and click the call button. i.e. controlling the specific Teams app running on my PC.

I am trying to achieve the following:

- I would like to make the call from my application via (I am assuming the graph API) and teams responds.

- I would like to monitor the state of the call so I can respond within my CRM accordingly (call duration, when the call is disconnected etc.).

- I would also like to monitor Teams so that if there is an incoming call I can notify my CRM and appropriately respond.

I have gone through the various github repositories but i wanted to know if the above functionality is available simply via a registered bot and all call initiations and responses on status of the call can be handled by a registered web service (nothing installed in the Team app) or does it need an bot within the teams app?

I realize this is quite a broad and general question but I keep going round in circles but i would appreciate a recommended approach if there is one.

Many thanks in advance.