Should I date a friend?

I have had a male friend i have known him 3 years. Hes a amazing friend. There for me when i need to talk and make me feel better and i always end up having a great laugh.We spend hours on the phone and talk about every thing. We have spoken to each other when we have had partners too.

Lately he has been flirting and i have been doing it back thinking its a bit of fun. Saying things like id come and give u a hug and we should catch up for a drink soon. Hes been calling me cute and good looking.We have been talking neally every day.He has been calling me babe too.He never use to do all of this.

So Im thinking what shall i do keep the friendship that i love or shall we try dating ?
I havent asked him this we keep flirting and we have said nothing about why we are doing it.

Please help?