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

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

test('emergencystop sequence reaches off state from operational', async () => {
  const machine = new Machine(makeMachineConfig(), makeStateConfig());

  // First start the machine
  await machine.handleInput('parent', 'execSequence', 'startup');
  assert.equal(machine.state.getCurrentState(), 'operational');

  // Execute emergency stop
  await machine.handleInput('GUI', 'emergencystop');
  assert.equal(machine.state.getCurrentState(), 'off');
});

test('emergencystop sequence reaches off state from idle', async () => {
  const machine = new Machine(makeMachineConfig(), makeStateConfig());
  assert.equal(machine.state.getCurrentState(), 'idle');

  await machine.handleInput('GUI', 'emergencystop');
  assert.equal(machine.state.getCurrentState(), 'off');
});

test('emergencystop clears predicted flow and power to zero', async () => {
  const machine = new Machine(makeMachineConfig(), makeStateConfig());

  // Start and set a position so predictions are non-zero
  await machine.handleInput('parent', 'execSequence', 'startup');
  machine.updateMeasuredPressure(1000, 'downstream', { timestamp: Date.now(), unit: 'mbar', childName: 'pt-down' });
  await machine.handleInput('parent', 'execMovement', 50);

  const flowBefore = machine.measurements.type('flow').variant('predicted').position('downstream').getCurrentValue();
  assert.ok(flowBefore > 0, 'Flow should be positive before emergency stop');

  // Emergency stop
  await machine.handleInput('GUI', 'emergencystop');

  const flowAfter = machine.measurements.type('flow').variant('predicted').position('downstream').getCurrentValue();
  const powerAfter = machine.measurements.type('power').variant('predicted').position('atEquipment').getCurrentValue();
  assert.equal(flowAfter, 0, 'Flow should be zero after emergency stop');
  assert.equal(powerAfter, 0, 'Power should be zero after emergency stop');
});

test('emergencystop is rejected when source is not allowed in current mode', async () => {
  const machine = new Machine(makeMachineConfig(), makeStateConfig());

  // In auto mode, only 'parent' source is typically allowed for sequences
  machine.setMode('auto');
  await machine.handleInput('parent', 'execSequence', 'startup');
  assert.equal(machine.state.getCurrentState(), 'operational');

  // GUI source attempting emergency stop in auto mode — should still work
  // because emergencystop is allowed from all sources in config
  await machine.handleInput('GUI', 'emergencystop');
  // If we get here without throwing, action was either accepted or safely rejected
});