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

const { Reactor_PFR } = require('../../src/specificClass');
const { makeReactorConfig } = require('../helpers/factories');

test('_applyBoundaryConditions enforces Danckwerts inlet and Neumann outlet for flowing case', () => {
  const reactor = new Reactor_PFR(
    makeReactorConfig({ reactor_type: 'PFR', n_inlets: 1, length: 10, resolution_L: 5, volume: 50, alpha: 0.2 }),
  );

  reactor.Fs[0] = 2;
  reactor.Cs_in[0] = Array(13).fill(9);
  reactor.D = 1;

  const state = Array.from({ length: reactor.n_x }, (_, i) => Array(13).fill(i));
  reactor._applyBoundaryConditions(state);

  assert.deepEqual(state[reactor.n_x - 1], state[reactor.n_x - 2]);
  assert.equal(state[0].every((v) => Number.isFinite(v)), true);
});

test('_applyBoundaryConditions copies first interior slice when no flow is present', () => {
  const reactor = new Reactor_PFR(
    makeReactorConfig({ reactor_type: 'PFR', n_inlets: 1, length: 10, resolution_L: 5, volume: 50 }),
  );

  reactor.Fs[0] = 0;
  const state = Array.from({ length: reactor.n_x }, (_, i) => Array(13).fill(i + 10));

  reactor._applyBoundaryConditions(state);

  assert.deepEqual(state[0], state[1]);
  assert.deepEqual(state[reactor.n_x - 1], state[reactor.n_x - 2]);
});