Always-on clock

I have a rooted device with an Amoled screen and Android 5.1 (CyanogenMod 12.1) installed. I would like to also use it as a desk/night clock. I know that with the Daydream (‘screensaver’) feature, I can get this, but only while charging, or docked. * Is it possible to allow Daydream also while on battery? * If not, is there another option? * Optional extra requirement: Ideally, the screen would turn of completely when it is covered. I prefer ‘simple’ solutions, but am also interested in ones that are more complicated and involve, e.g., some form of automation. (They may also be of interest to others.)