#!/usr/bin/env qjs

//it is possible to generate the solution space automatically
//but it is so small that it is easier to just supply it manually
var solutionSpace= [
			{"A":"truth", "B":"liar","C":"random"},
			{"A":"liar","B":"truth","C":"random"},
			{"A":"random","B":"truth","C":"liar"},
			{"A":"random","B":"liar","C":"truth"},
			{"A":"truth","B":"random","C":"liar"},
			{"A":"liar","B":"random","C":"truth" }
		   ];

//constraint.index is just for the purpose of reference
var constraints = [ 
	{"index":"a","who_says":"A","B_is":"truth"},
	{"index":"b","who_says":"B", "B_is":"random"},
	{"index":"c","who_says":"C", "B_is":"liar"}
	];

//we iterate over every potential solution in the solution space
for(var solution of solutionSpace) {
	var B=solution["B"];
    console.log("--------------------------");
    //A and C are just for printing the potential solution
    //they are not needed for the algorithm
	var A=solution["A"];
	var C=solution["C"];
    console.log("checking: "+A+" "+B+" "+C);
    //we assume that the solution is valid, until it isn't anymore.
    var abort_solution=false;
    //now we check every constraint for the current potential solution
    for(var constraint of constraints) {
        var index=constraint["index"];
        var who_says=constraint["who_says"];
        var B_is=constraint["B_is"];
        //check 1: truth is not allowed to lie about B
        if(solution[who_says]=="truth" && B!==B_is) {
            console.log("violation of constraint ("+index+
                "); truth is not allowed to lie and say that "+B+" is "+B_is);
            abort_solution=true;
            break;
        }
        //check 2: liar is not allowed to tell the truth about
        if(solution[who_says]=="liar" && B==B_is) {
            console.log("violation of constraint ("+index+
                "); liar is not allowed to tell the truth and say that "+B+" is "+B_is);
            abort_solution=true;
            break;
        }
        //we cannot check random; so, no check for that one
    }
    if(!abort_solution) console.log("found legitimate solution");
}
console.log("--------------------------");