// Constants definition
//

// Automaton definition
//
automaton evader
contr_var: e, p, x; // e position of the evader
                    // p position of the pursuer
                    // x timer
synclabs: jump;
loc ClkW: 
    while 0 <= e <= 40 & 0 <= p <= 40 & x <= 2 wait
        {e'==5 & -0.5 <= p' <= 6 & x'==1}
    when (p == 0) sync jump do {e'==e & p'==40 & x'==x} goto ClkW;
    when (p == 40) sync jump do {e'==e & p'==0 & x'==x} goto ClkW;
    when (x >= 2) & (0 < e < 40) & (6*e - 5*p > 40) sync jump do 
        {e'==e & p'==p & x'==0} goto ClkW;
    when (x >= 2) & (0 < e < 40) & (6*e - 5*p <= 40) sync jump do 
        {e'==e & p'==p & x'==0} goto CntrClkW;
    when (e == 0) sync jump do {e'==e & p'==p & x'==x} goto Rescued;
    when (e == 40) sync jump do {e'==e & p'==p & x'==x} goto Rescued;
loc CntrClkW: 
    while 0 <= e <= 40 & 0 <= p <= 40 & x <= 2 wait
        {e'==-5 & -0.5 <= p' <= 6 & x'==1}
    when (p == 0) sync jump do {e'==e & p'==40 & x'==x} goto CntrClkW;
    when (p == 40) sync jump do {e'==e & p'==0 & x'==x} goto CntrClkW;
    when (x >= 2) & (0 < e < 40) & (6*e - 5*p > 40) sync jump do 
        {e'==e & p'==p & x'==0} goto ClkW;
    when (x >= 2) & (0 < e < 40) & (6*e - 5*p <= 40) sync jump do 
        {e'==e & p'==p & x'==0} goto CntrClkW;
    when (e == 0) sync jump do {e'==e & p'==p & x'==x} goto Rescued;
    when (e == 40) sync jump do {e'==e & p'==p & x'==x} goto Rescued;
loc Rescued:
    while true wait {e'==0 & p'==0 & x'==0 };

initially: ClkW & x == 2 & e == 20 & p == 10;
end

// Compute the reachable set
//
region=evader.reachable;
//
// Output to file
//
// List regions (pairs of locations names and linear formulas)
region.print("evader_regions.txt", 0);
// Sequence of vertices in floating point form.
// Can be plotted with gnuplot
// Project on e and p
region.project_to(e, p);
region.print("evader.txt", 2);

// Safety verification
//
// definition of bad states
forbidden = evader.{$ & e == p};
reach_set = evader.is_reachable(forbidden);
reach_set.intersection_assign(forbidden);

echo "The intersection between the reachable set and the bad region is:";
reach_set.is_empty;