Конечные автоматы JS

 const array = ["A1B","A2C","A3D","B1C","B2A","A1A","C2C","C3A"];

commands = [1, 1, 1];

var stateMachine = {};
 
stateMachine.Rule = class {
  constructor (state, rule, next) {
    this.state = state;
    this.rule = rule;
    this.next = next;
  }
 
  isApplies (state, rule) {
    return this.state == state && this.rule == rule
  }
 
  follow () {
    return this.next
  }
}
 
stateMachine.NRulebook = class {
  constructor (rules) {
    this.rules = rules
  }
 
  nextStates (states, rule) {
    var result = [];
 
    states.forEach(state => {
      result = result.concat(this.rulesFor(state, rule).map(r => r.follow()))
    });
 
    return Array.from(new Set(result).values())
  }
 
  rulesFor (state, rule) {
    return this.rules.filter(r => r.isApplies(state, rule))
  }
 
  static from (array) {
    return new this(array.map(rule => {
      var vals = rule.split('');
 
      return new stateMachine.Rule(vals[0], parseInt(vals[1], 10), vals[2])
    }));
  }
}
 
stateMachine.NSM = class {
  constructor (startState, acceptStates, rulebook) {
    this.states = [startState];
    this.acceptStates = acceptStates;
    this.rulebook = rulebook;
  }
 
  next (step) {
    this.states = this.rulebook.nextStates(this.states, step);
 
    return this;
  }
 
  readSteps (steps) {
    steps.forEach(step => this.next(step));
 
    return this;
  }
 
  isAccepting () {
    for (var state of this.states) {
      if (this.acceptStates.includes(state)) return true
    }
 
    return false
  }
}
 
stateMachine.NSMFactory = class {
  constructor (params) {
    this.startState = params.startState;
    this.acceptStates = params.acceptStates;
    this.rulebook = params.rulebook;
  }
 
  isAccepting (steps) {
    return new stateMachine.NSM(this.startState, this.acceptStates, this.rulebook)
      .readSteps(steps)
      .isAccepting()
  }
}
 
const array = ["A1A", "A1B", "A2C", "A3D", "B1C", "B2A", "C2C", "C3A"];
 
var nsm = new stateMachine.NSMFactory({
  startState: 'A',
  acceptStates: ['A', 'B', 'C', 'D'],
  rulebook: stateMachine.NRulebook.from(array)
});
 
console.log(nsm.isAccepting([1, 1, 1])); //=> true
console.log(nsm.isAccepting([1, 2, 2, 1])); //=> false
console.log(nsm.isAccepting([3, 1])); //=> false
console.log(nsm.isAccepting([2, 3, 2, 3])); //=> true