My own media_player

Hi,
I’m totaly new to Home Assistant. Yesterday I started converting my ESP8266 from REST based standalone systems to MQTT. At this point I’m able to controll my heating, see the temperature and switch my power outlets via HS.

But now I’m struggeling…
I want to controll my PC media system as well - Play, Pause, Next, Volume up / down.
My System is based aroud Winamp and a C# program that is able to controll Winamp via Rest / Tcp / (mqtt if necessary) calls.
Everything I need to be happy are some buttons which are able to send MQTT and are “non boolean” - just like normal buttons.
But I’m can’t find them :frowning2:

Or, even better, is there a way to create my own Media_Player, like the KODI player, based on MQTT?
So by pressing the play button, a MQTT message “play” is send to /room/media/winamp?

Thx for your help
jonas