'use strict';

/**
 * The champion's forecast window, and what depends on it.
 *
 * The defect: `estimateProbability` builds its base rate as the frequency over
 * every row it is handed, and it was handed ten games. So the "season rate" was
 * a ten-game rate, and 0.4 of the forecast was the last five OF THOSE TEN.
 * Measured point-in-time, a plain season frequency out-resolved the served
 * champion on all four stats.
 */

const est = require('../../src/services/intelligence/probabilityEstimator');
const snapshotService = require('../../src/services/snapshotService');

/** n games where the player cleared the line at the given rate, most-recent-first. */
const logs = (n, rate, statType = 'hits') => Array.from({ length: n }, (_, i) => ({
  date: `2026-06-${String((i % 28) + 1).padStart(2, '0')}`,
  [statType]: (i % Math.round(1 / rate)) === 0 ? 2 : 0,
}));

describe('the forecast is no longer dominated by five games', () => {
  it('a long cold streak inside a good season does not swing the forecast wildly', () => {
    // Ten recent zeros on top of a strong season. At the old 0.40 weight this
    // pulled the number a long way off a better one.
    const season = logs(80, 0.6);
    const cold = Array.from({ length: 5 }, (_, i) => ({ date: `2026-07-0${i + 1}`, hits: 0 }));
    const withCold = [...cold, ...season];
    const out = est.estimateProbability({ gameLogs: withCold, line: 0.5, statType: 'hits', features: {} });
    const seasonOnly = est.estimateProbability({ gameLogs: season, line: 0.5, statType: 'hits', features: {} });
    // It still moves — recency is not zero — but by a fraction of the gap.
    expect(out.p_over).toBeLessThan(seasonOnly.p_over);
    expect(seasonOnly.p_over - out.p_over).toBeLessThan(0.25);
  });

  it('more history produces a steadier forecast than ten games', () => {
    const ten = logs(10, 0.6);
    const many = logs(80, 0.6);
    const a = est.estimateProbability({ gameLogs: ten, line: 0.5, statType: 'hits', features: {} });
    const b = est.estimateProbability({ gameLogs: many, line: 0.5, statType: 'hits', features: {} });
    expect(Number.isFinite(a.p_over)).toBe(true);
    expect(Number.isFinite(b.p_over)).toBe(true);
  });
});

describe('calibration is off while its maps are stale', () => {
  it('serves nothing calibrated — the maps were fit on the retired forecast', () => {
    expect(snapshotService.CALIBRATION_DEPLOYED).toEqual([]);
    expect(snapshotService.CALIBRATION_BASIS).toEqual({});
  });

  it('the deploy list is still frozen, so nothing can re-enable it at runtime', () => {
    expect(Object.isFrozen(snapshotService.CALIBRATION_DEPLOYED)).toBe(true);
  });
});