PIC18F458 (main and ISR flowchart)

Can someone help me to come out with a main program and ISR flowchart of this circuit below (pic18f458), it is about a car system, with start engine, stop engine, lock door, unlock door and alarm (following sequence - basic steps to get into a car: unlock the door, start engine, lock the door... etc). Just a simple flowchart, without ADC and USART. Just use 1.5s delay and TIMER0

Input (Switches):

START -------> RB0/INT0...

PIC18F458 (main and ISR flowchart)