Ring Security Floodlight Wiring

Hi. I have an existing floodlight that has a seperate pir sensor. I want to wire up the new ring floodlight with built in PIR and use both original and ring PIR. The existing floodlight can be turned on constantly with a light switch. When turned off it reverts back to PIR mode. Does anyone know how this would be wired in with the new system in parallel. A diagram would be very helpful if possible. Thanks