Change parents text color according background contrast

I had problem with subscribing to ab-color-found so i patched plugin for my needs.

When we change color of background, color of text do not always match background, dark text on dark background and vice versa, so it would be great if this plugin have native support for this.

Seems to me that this is common problem with changing background, i would like to hear other thoughts on this.

Cheers,
Aleksandar