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

const { showWorkingCurves, showCoG } = require('../../src/display/workingCurves');

function makePredictors(overrides = {}) {
  return {
    hasCurve: true,
    cog: 0.65,
    cogIndex: 7,
    NCog: 0.5,
    minEfficiency: 0.4,
    currentEfficiencyCurve: { x: [0, 1], y: [0.4, 0.8] },
    absDistFromPeak: 0.15,
    relDistFromPeak: 0.3,
    calcCog: () => ({ cog: 0.65, cogIndex: 7, NCog: 0.5, minEfficiency: 0.4 }),
    getCurrentCurves: () => ({
      powerCurve: { x: [0, 1], y: [10, 20] },
      flowCurve:  { x: [0, 1], y: [0, 5] },
    }),
    ...overrides,
  };
}

test('showWorkingCurves returns the expected shape when curves exist', () => {
  const p = makePredictors();
  const out = showWorkingCurves(p);
  assert.deepEqual(out.powerCurve, { x: [0, 1], y: [10, 20] });
  assert.deepEqual(out.flowCurve,  { x: [0, 1], y: [0, 5] });
  assert.equal(out.cog, 0.65);
  assert.equal(out.cogIndex, 7);
  assert.equal(out.NCog, 0.5);
  assert.equal(out.minEfficiency, 0.4);
  assert.deepEqual(out.currentEfficiencyCurve, { x: [0, 1], y: [0.4, 0.8] });
  assert.equal(out.absDistFromPeak, 0.15);
  assert.equal(out.relDistFromPeak, 0.3);
});

test('showWorkingCurves returns error envelope when hasCurve is false', () => {
  const out = showWorkingCurves(makePredictors({ hasCurve: false }));
  assert.deepEqual(out, { error: 'No curve data available' });
});

test('showWorkingCurves handles null predictors safely', () => {
  const out = showWorkingCurves(null);
  assert.equal(out.error, 'No curve data available');
});

test('showCoG returns CoG data with rounded NCogPercent when curves exist', () => {
  const p = makePredictors();
  const out = showCoG(p);
  assert.equal(out.cog, 0.65);
  assert.equal(out.cogIndex, 7);
  assert.equal(out.NCog, 0.5);
  // 0.5 * 100 = 50.0, rounded *100 /100 still 50
  assert.equal(out.NCogPercent, 50);
  assert.equal(out.minEfficiency, 0.4);
  assert.deepEqual(out.currentEfficiencyCurve, { x: [0, 1], y: [0.4, 0.8] });
  assert.equal(out.absDistFromPeak, 0.15);
  assert.equal(out.relDistFromPeak, 0.3);
});

test('showCoG rounds NCogPercent to 2 decimal places', () => {
  const p = makePredictors({
    calcCog: () => ({ cog: 0.1, cogIndex: 1, NCog: 0.123456, minEfficiency: 0.2 }),
  });
  const out = showCoG(p);
  assert.equal(out.NCogPercent, 12.35);
});

test('showCoG returns degraded shape when hasCurve is false', () => {
  const out = showCoG(makePredictors({ hasCurve: false }));
  assert.equal(out.error, 'No curve data available');
  assert.equal(out.cog, 0);
  assert.equal(out.NCog, 0);
  assert.equal(out.cogIndex, 0);
});

test('showCoG handles null predictors safely', () => {
  const out = showCoG(null);
  assert.equal(out.error, 'No curve data available');
  assert.equal(out.cog, 0);
});