Design of a valve controller

I am looking for someone to design a valve controller. Here is what it will accomplish 12 volt power will be supplied to it via the car battery (always on) the ignition switch (only on when the ignition switch is in the on position). "Start process" The controller will receive 12v from the battery and ignition. Power will be supplied to LED #1. Thermostat will receive 12v also. Once the thermostat passes the 12v back to the controller, the valves will receive 12v. (opening the valves). Power will then be supplied to LED #3 and removed from LED #1. "End process" When a button is pushed the controller will remove 12v from the supply valve (closing it) and at the same time activate a timer. Power will also be supplied to LED #2 and removed from LED #3. When the timer reaches zero the controller will remove 12v from the return valve and LED #2. Power will then be supplied to LED #1. If the 12 volts from the ignition switch is removed without the button being pushed the controller will send 12v to signaler . Once 12v is supplied from the ignition again the 12v to the signaler will stop. The button will be pushed and the "End process” will start. The controller should fit in a plastic box approx 4"x3"x1" I am looking for two things 1. A schematic for this controller 2. A built and working unit