flash to pass and dip/main relay

If I knew what sort of relay I need perhaps I could have found the answer with the search function, but I don't, so I couldn't! What I want to do is have a momentary switch operate a flash to pass function when my headlights are off, and act as the dip switch when the headlights are on, but the system relay should revert to the dip position when the lights are switched off. I have a latching DPDT relay that will accomplish the first two requirements but not the third one as it retains its last position when the lights are switched off with the result that if the lights are switched off when on main beam, they come back on on main beam and not on dip. Can anyone suggest how this can be accomplished as simply as possible?

I reckon use a flip flop or a 4017 for the dip feature. (That's been mentioned a few times on the12volt.) The flasher can be added to whatever circuit you choose.