import FSM from "./fsm.mjs";
import assert from "assert";

const add_test = () => {
  console.log("Additional function call on state transition passed.");
}

class TestMachine {
  constructor(data) {
    console.log("DATA IS", data);
    this.data = data;
  }

  async open(state, inc) {
    switch(state) {
      case "START":
        console.log("THIS", this);
        this.data.count = this.data.count + inc;
        return "OPEN";
      default:
        return "ERROR";
    }
  }

  close(state, inc) {
    switch(state) {
      case "OPEN":
        this.data.count = this.data.count + inc;
        return ["CLOSED", add_test];
      default:
        return "ERROR";
    }
  }
}


let data = {count: 0};
let events = new TestMachine(data);
let fsm1 = new FSM(data, events);

fsm1.onTransition((fsm) => {
  console.log("On transition: ", fsm.state);
});

await fsm1.do('open', 3);
assert(fsm1.state === "OPEN");
assert(data.count === 3);

await fsm1.do('close', 4);
assert(fsm1.state === "CLOSED");
assert(data.count === 7);

// test the errors
await fsm1.do('open');
assert(fsm1.state === "ERROR");
assert(data.count === 7); // still 2 after error