const test = require('node:test');
const assert = require('node:assert/strict');

const Machine = require('../../src/specificClass');
const { makeMachineConfig, makeStateConfig } = require('../helpers/factories');

/**
 * Regression tests for the FSM interruptible-movement fix (2026-04-13).
 *
 * Before the fix, `executeSequence("shutdown")` was silently rejected by the
 * state manager if the machine was mid-move (accelerating/decelerating),
 * because allowedTransitions for those states only permits returning to
 * `operational` or `emergencystop`. Operators pressing Stop during a ramp
 * would see the transition error-logged but no actual stop.
 *
 * The fix aborts the active movement, waits for the FSM to return to
 * `operational`, then runs the normal shutdown / emergency-stop sequence.
 */

const sleep = (ms) => new Promise((r) => setTimeout(r, ms));

function makeSlowMoveMachine() {
  // Slow movement so the test can reliably interrupt during accelerating.
  // speed=20%/s, interval=10ms -> 80% setpoint takes ~4s of real movement.
  return new Machine(
    makeMachineConfig(),
    makeStateConfig({
      movement: { mode: 'staticspeed', speed: 20, maxSpeed: 1000, interval: 10 },
      time: { starting: 0, warmingup: 0, stopping: 0, coolingdown: 0 },
    })
  );
}

test('shutdown during accelerating aborts the move and reaches idle', async () => {
  const machine = makeSlowMoveMachine();

  await machine.handleInput('parent', 'execSequence', 'startup');
  assert.equal(machine.state.getCurrentState(), 'operational');
  machine.updateMeasuredPressure(1000, 'downstream', { timestamp: Date.now(), unit: 'mbar', childName: 'pt-down' });
  machine.updateMeasuredPressure(200, 'upstream', { timestamp: Date.now(), unit: 'mbar', childName: 'pt-up' });

  // Fire a setpoint that needs ~4 seconds. Do NOT await it.
  const movePromise = machine.handleInput('parent', 'execMovement', 80);

  // Wait a moment for the FSM to enter accelerating.
  await sleep(100);
  assert.equal(machine.state.getCurrentState(), 'accelerating');

  // Issue shutdown while the move is still accelerating.
  await machine.handleInput('GUI', 'execSequence', 'shutdown');

  // Let the aborted move unwind.
  await movePromise.catch(() => {});

  assert.equal(
    machine.state.getCurrentState(),
    'idle',
    'shutdown issued mid-ramp must still drive FSM back to idle',
  );
});

test('emergency stop during accelerating reaches off', async () => {
  const machine = makeSlowMoveMachine();

  await machine.handleInput('parent', 'execSequence', 'startup');
  machine.updateMeasuredPressure(1000, 'downstream', { timestamp: Date.now(), unit: 'mbar', childName: 'pt-down' });

  const movePromise = machine.handleInput('parent', 'execMovement', 80);

  await sleep(100);
  assert.equal(machine.state.getCurrentState(), 'accelerating');

  await machine.handleInput('GUI', 'emergencystop');
  await movePromise.catch(() => {});

  assert.equal(
    machine.state.getCurrentState(),
    'off',
    'emergency stop issued mid-ramp must still drive FSM to off',
  );
});

test('executeSequence accepts mixed-case sequence names', async () => {
  const machine = new Machine(makeMachineConfig(), makeStateConfig());
  await machine.handleInput('parent', 'execSequence', 'startup');
  assert.equal(machine.state.getCurrentState(), 'operational');

  // Parent orchestrators (e.g. machineGroupControl) use "emergencyStop" with
  // a capital S in their configs. The sequence key in rotatingMachine.json
  // is lowercase. Normalization must bridge that gap without a warn.
  await machine.executeSequence('EmergencyStop');
  assert.equal(machine.state.getCurrentState(), 'off');
});