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

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

/**
 * Prediction benchmarks across all rotatingMachine curves currently shipped
 * with generalFunctions. This guards the curve-backed prediction path against
 * regressions in the loader, the reverse-nq inversion, and the pressure
 * slicing logic — across machines of very different sizes.
 *
 * Ranges are derived from the curve data itself (loaded at test time) plus
 * physical sanity properties (monotonicity in ctrl, inverse-monotonicity in
 * pressure for flow, non-negative power, curve-backed CoG non-zero).
 */

// Curves the node is expected to support. Add new entries here as soon as a
// new curve file lands in generalFunctions/datasets/assetData/curves/.
const PUMP_CURVES = [
  { model: 'hidrostal-H05K-S03R', unit: 'm3/h', pUnit: 'mbar', powUnit: 'kW' },
  { model: 'hidrostal-C5-D03R-SHN1', unit: 'm3/h', pUnit: 'mbar', powUnit: 'kW' },
];

function curveExtents(curveData) {
  const pressures = Object.keys(curveData.nq)
    .filter((k) => /^-?\d+$/.test(k))
    .map(Number)
    .sort((a, b) => a - b);
  const slice = (set, p) => curveData[set][String(p)];
  const lowP = pressures[0];
  const midP = pressures[Math.floor(pressures.length / 2)];
  const highP = pressures[pressures.length - 1];
  const allFlowY = pressures.flatMap((p) => slice('nq', p).y);
  const allPowerY = pressures.flatMap((p) => slice('np', p).y);
  return {
    pressures,
    lowP, midP, highP,
    flowMin: Math.min(...allFlowY), flowMax: Math.max(...allFlowY),
    powerMin: Math.min(...allPowerY), powerMax: Math.max(...allPowerY),
  };
}

async function makeRunningMachine({ model, unit }) {
  const cfg = makeMachineConfig({
    general: { id: `rm-${model}`, name: model, unit, logging: { enabled: false, logLevel: 'error' } },
    asset: {
      supplier: 'hidrostal', category: 'pump', type: 'Centrifugal', model, unit,
      curveUnits: { pressure: 'mbar', flow: unit, power: 'kW', control: '%' },
    },
  });
  const m = new Machine(cfg, makeStateConfig());
  await m.handleInput('parent', 'execSequence', 'startup');
  assert.equal(m.state.getCurrentState(), 'operational', `${model}: should reach operational`);
  return m;
}

for (const curve of PUMP_CURVES) {
  const { model, unit, pUnit, powUnit } = curve;

  test(`[${model}] curve loads and has both nq and np slices`, () => {
    const raw = loadCurve(model);
    assert.ok(raw, `loadCurve('${model}') must return data`);
    assert.ok(raw.nq && Object.keys(raw.nq).length > 0, `${model}: nq has pressure slices`);
    assert.ok(raw.np && Object.keys(raw.np).length > 0, `${model}: np has pressure slices`);
    // Same pressure slices in both
    const nqP = Object.keys(raw.nq).filter((k) => /^-?\d+$/.test(k)).sort();
    const npP = Object.keys(raw.np).filter((k) => /^-?\d+$/.test(k)).sort();
    assert.deepEqual(nqP, npP, `${model}: nq and np must share pressure slices`);
  });

  test(`[${model}] predicted flow and power at mid-pressure, mid-ctrl are finite and in-range`, async () => {
    const raw = loadCurve(model);
    const ext = curveExtents(raw);
    const m = await makeRunningMachine(curve);

    // Feed differential pressure = midP (upstream 0, downstream = midP)
    m.updateMeasuredPressure(0, 'upstream', { timestamp: Date.now(), unit: pUnit, childName: 'pt-up' });
    m.updateMeasuredPressure(ext.midP, 'downstream', { timestamp: Date.now(), unit: pUnit, childName: 'pt-down' });

    await m.handleInput('parent', 'execMovement', 50);

    const flow = m.measurements.type('flow').variant('predicted').position('downstream').getCurrentValue(unit);
    const power = m.measurements.type('power').variant('predicted').position('atEquipment').getCurrentValue(powUnit);

    assert.ok(Number.isFinite(flow), `${model}: flow must be finite`);
    assert.ok(Number.isFinite(power), `${model}: power must be finite`);
    // Flow can be negative at the low-end slice of some curves due to spline extrapolation,
    // but at mid-pressure mid-ctrl it must be positive.
    assert.ok(flow > 0, `${model}: flow ${flow} ${unit} must be > 0 at mid-pressure mid-ctrl`);
    assert.ok(power >= 0, `${model}: power ${power} ${powUnit} must be >= 0`);
    // Loose bracket against curve envelope (2x margin accommodates interpolation overshoot)
    assert.ok(flow <= ext.flowMax * 2, `${model}: flow ${flow} exceeds curve envelope ${ext.flowMax}`);
    assert.ok(power <= ext.powerMax * 2, `${model}: power ${power} exceeds curve envelope ${ext.powerMax}`);
  });

  test(`[${model}] flow is monotonically non-decreasing in ctrl at fixed pressure`, async () => {
    const raw = loadCurve(model);
    const ext = curveExtents(raw);
    const m = await makeRunningMachine(curve);
    m.updateMeasuredPressure(0, 'upstream', { timestamp: Date.now(), unit: pUnit, childName: 'pt-up' });
    m.updateMeasuredPressure(ext.midP, 'downstream', { timestamp: Date.now(), unit: pUnit, childName: 'pt-down' });

    const samples = [];
    for (const setpoint of [10, 30, 50, 70, 90]) {
      await m.handleInput('parent', 'execMovement', setpoint);
      const flow = m.measurements.type('flow').variant('predicted').position('downstream').getCurrentValue(unit);
      samples.push({ setpoint, flow });
    }

    for (let i = 1; i < samples.length; i++) {
      // Allow 1% tolerance for spline wiggle but reject any clear regression.
      assert.ok(
        samples[i].flow >= samples[i - 1].flow - Math.abs(samples[i - 1].flow) * 0.01,
        `${model}: flow not monotonic across ctrl sweep: ${JSON.stringify(samples)}`,
      );
    }
  });

  test(`[${model}] flow decreases (or stays level) when pressure rises at fixed ctrl`, async () => {
    const raw = loadCurve(model);
    const ext = curveExtents(raw);
    const m = await makeRunningMachine(curve);

    const samples = [];
    for (const p of [ext.lowP, ext.midP, ext.highP]) {
      m.updateMeasuredPressure(0, 'upstream', { timestamp: Date.now(), unit: pUnit, childName: 'pt-up' });
      m.updateMeasuredPressure(p, 'downstream', { timestamp: Date.now(), unit: pUnit, childName: 'pt-down' });
      await m.handleInput('parent', 'execMovement', 60);
      const flow = m.measurements.type('flow').variant('predicted').position('downstream').getCurrentValue(unit);
      samples.push({ pressure: p, flow });
    }

    // Highest pressure must not exceed lowest pressure flow by more than 1%.
    // (Centrifugal pump: head up -> flow down at a given speed.)
    const first = samples[0].flow;
    const last = samples[samples.length - 1].flow;
    assert.ok(
      last <= first * 1.01,
      `${model}: flow at p=${samples[samples.length - 1].pressure} (${last}) exceeds flow at p=${samples[0].pressure} (${first}); samples=${JSON.stringify(samples)}`,
    );
  });

  test(`[${model}] cog and NCog are computed and finite after an operational move`, async () => {
    const raw = loadCurve(model);
    const ext = curveExtents(raw);
    const m = await makeRunningMachine(curve);
    m.updateMeasuredPressure(0, 'upstream', { timestamp: Date.now(), unit: pUnit, childName: 'pt-up' });
    m.updateMeasuredPressure(ext.midP, 'downstream', { timestamp: Date.now(), unit: pUnit, childName: 'pt-down' });
    await m.handleInput('parent', 'execMovement', 50);

    assert.ok(Number.isFinite(m.cog), `${model}: cog must be finite, got ${m.cog}`);
    assert.ok(Number.isFinite(m.NCog), `${model}: NCog must be finite, got ${m.NCog}`);
    // CoG is a controller-% location of peak efficiency; must fall inside the ctrl range of the curve.
    assert.ok(m.cog >= 0 && m.cog <= 100, `${model}: cog=${m.cog} must be within [0,100]`);
  });

  test(`[${model}] reverse predictor (ctrl for requested flow) round-trips within tolerance`, async () => {
    const raw = loadCurve(model);
    const ext = curveExtents(raw);
    const m = await makeRunningMachine(curve);
    m.updateMeasuredPressure(0, 'upstream', { timestamp: Date.now(), unit: pUnit, childName: 'pt-up' });
    m.updateMeasuredPressure(ext.midP, 'downstream', { timestamp: Date.now(), unit: pUnit, childName: 'pt-down' });

    // Move to a known controller position and read the flow.
    await m.handleInput('parent', 'execMovement', 60);
    const observedFlow = m.measurements.type('flow').variant('predicted').position('downstream').getCurrentValue(unit);
    assert.ok(observedFlow > 0, `${model}: need non-zero flow to invert`);

    // Convert flow back to ctrl via calcCtrl (uses reversed nq internally) —
    // note calcCtrl takes canonical flow (m3/s), so convert.
    const canonicalFlow = observedFlow / 3600; // m3/h -> m3/s
    const predictedCtrl = m.calcCtrl(canonicalFlow);
    assert.ok(
      Number.isFinite(predictedCtrl) && Math.abs(predictedCtrl - 60) <= 10,
      `${model}: reverse predictor ctrl=${predictedCtrl} should be within 10 of 60 for flow=${observedFlow}`,
    );
  });
}