HiFiBerry DAC+ DSP

Hi I'm interested to buy DAC+ DSO board. I'd like to know can I achieve with HiFiBerry DAC+ DSP some scenario. I have analog D amplifier stereo system with 1 input. I'd like to add Raspberry pi to this system for playing audio and also to connect TV via toslink to DAC. Will this work out of rhe box TV-toslink-audio out? Or do I need apply some filters/ settings. Are they any available to download presets or do I need to tinker them myself. I'm intermediate advanced so following some manuals I'm ok to make it. Once I'll get such a connection how it works? Let's say I'm playing music from Volumio or hifiberry os, and then someone will turn on TV. Are both signal mixed, or RPi sound is switched to toslink, or every time sound input need to be switched manually? My optimal settings is that toslink is active all the time waiting for signal from tv, and if I want listen to the music I don't need to change anything, just playing from Pi. Regards