#!/usr/bin/env node
'use strict';

/**
 * THE COLLAPSED SEQUENCE EDGE — Link 1 x pen-season-quality, on later at-bats.
 *
 * Link 3 is correctly skipped: reliever IDENTITY did not prove and is genuine
 * baseball unpredictability. But Link 2's QUALITY grain DID prove, so pen quality
 * here is a measured predictor rather than a fallback.
 *
 * ── THE MECHANICAL CEILING, MEASURED FIRST ───────────────────────────────
 * A hitter's third or fourth plate appearance is ALREADY against the bullpen
 * 70-73% of the time even when the starter is projected to go deep. An elevated
 * early-exit flag lifts that to only 77-83%. So Link 1 buys roughly TEN POINTS
 * of extra pen exposure, not a switch from starter to pen — and any adjustment
 * built on it is bounded at about a tenth of the starter-versus-pen quality gap.
 * That ceiling is a property of baseball, not of the model, and it is the reason
 * the deltas below are small before anything is even fitted.
 *
 * ── WHAT IS ADJUSTED, AND WHAT IS REFUSED ────────────────────────────────
 * The order specifies pen-quality x pen-ARCHETYPE x hitter-APPROACH. Two of
 * those three cannot be used honestly:
 *
 *   pen archetype     did NOT prove (0.5669 vs a 0.5309 modal baseline, corrected
 *                     interval spanning zero). Building it into the adjustment
 *                     would be chaining on an unproven link.
 *   hitter approach   "fastball-hunter" / "finesse-vulnerable" identities do not
 *                     exist in this registry. MLB batter archetypes are BOMBER /
 *                     GHOST / TORCH / BRUSH / DRIVER / FLEX / ALPHA / HYBRID /
 *                     CATALYST. Inventing an identity to condition on would be
 *                     fabricating the very thing the gate exists to catch.
 *
 * So the adjustment uses the PROVEN component alone, and a hitter split derived
 * from the sequence data itself (power vs contact by home-run rate) is tested as
 * a SEPARATE gated addition rather than assumed into the main effect.
 *
 *   node scripts/collapsed-sequence-edge.js
 */

require('dotenv').config();
const fs = require('fs');
const path = require('path');
const fg = require('../src/services/model/factorGate');
const tl = require('../src/services/model/testLedger');
const pq = require('../src/services/model/penQuality');
const { createClient } = require('@supabase/supabase-js');

const CACHE = process.env.SEQ_OUT || path.join(process.cwd(), '.seq-cache', 'sequences.json');
const HIT = new Set(['single', 'double', 'triple', 'home_run']);
const PA = new Set(['single', 'double', 'triple', 'home_run', 'field_out', 'strikeout',
  'grounded_into_double_play', 'force_out', 'field_error', 'fielders_choice',
  'fielders_choice_out', 'double_play', 'sac_fly', 'pop_out', 'line_out', 'fly_out',
  'strikeout_double_play']);

const MIN_ARM_PA = 40;
const MIN_PRIOR_GAMES = 5;
const MIN_HITTER_PA = 60;
const MIN_PRIOR_STARTS = 3;
const EARLY_FLAG_BF = 22;
const LEAGUE_BF = 21.56;

const mean = (xs) => (xs.length ? xs.reduce((a, b) => a + b, 0) / xs.length : null);

function build() {
  const { games } = JSON.parse(fs.readFileSync(CACHE, 'utf8'));
  games.sort((a, b) => String(a.date).localeCompare(String(b.date)) || a.gamePk - b.gamePk);

  const arm = new Map();
  const bat = new Map();          // hitter -> { n, h, hr }
  const penHist = new Map();
  const startHist = new Map();
  const rows = [];

  for (const g of games) {
    for (const side of ['home', 'away']) {
      const team = g[side].abbr || g[side].team;
      const st = (g[side].arms || []).find((a) => a.started);
      if (!team || !st) continue;
      const half = side === 'home' ? 'top' : 'bottom';
      const pas = g.pas.filter((p) => p.half === half && PA.has(p.event));

      const ps = startHist.get(st.id) || [];
      let predBf = null;
      if (ps.length >= MIN_PRIOR_STARTS) {
        const w = ps.length / (ps.length + 5);
        predBf = w * mean(ps) + (1 - w) * LEAGUE_BF;
      }
      const hist = penHist.get(team) || [];
      const pen = pq.projectPen(hist.map((q) => ({ quality: q })));

      const seen = new Map();
      for (const p of pas) {
        const k = p.batter;
        seen.set(k, (seen.get(k) || 0) + 1);
        const paNum = seen.get(k);
        const b = bat.get(k);
        // knownRate abstain: no readable hitter, starter or pen -> no row at all.
        if (paNum < 3 || predBf === null || !pen || !b || b.n < MIN_HITTER_PA) continue;
        rows.push({
          gamePk: g.gamePk,
          cluster: g.gamePk,
          batter: k,
          paNum,
          early: predBf <= EARLY_FLAG_BF,
          pen_quality: pen.quality,
          hitter_base: b.h / b.n,
          hitter_hr_rate: b.hr / b.n,
          won: HIT.has(p.event) ? 1 : 0,
        });
      }

      const faced = [];
      for (const p of pas.filter((x) => x.pitcher !== st.id)) {
        const h = arm.get(p.pitcher);
        if (h && h.n >= MIN_ARM_PA) faced.push(h.h / h.n);
      }
      if (faced.length) penHist.set(team, hist.concat([mean(faced)]));
      if (st.bf != null) startHist.set(st.id, ps.concat([st.bf]));
      for (const p of pas) {
        const c = arm.get(p.pitcher) || { n: 0, h: 0, k: 0 };
        c.n += 1; c.h += HIT.has(p.event) ? 1 : 0; c.k += p.event === 'strikeout' ? 1 : 0;
        arm.set(p.pitcher, c);
      }
      for (const p of pas) {
        const c = bat.get(p.batter) || { n: 0, h: 0, hr: 0 };
        c.n += 1; c.h += HIT.has(p.event) ? 1 : 0; c.hr += p.event === 'home_run' ? 1 : 0;
        bat.set(p.batter, c);
      }
    }
  }
  return rows;
}

/** The adjustment: the hitter's own rate, shifted by the PROVEN pen signal. */
const adjust = (r) => {
  const shift = pq.hitRateShift(r.pen_quality);
  if (shift === null) return null;
  return Math.max(0.01, Math.min(0.99, r.hitter_base + shift));
};

(async () => {
  const all = build();
  const qs = all.map((r) => r.pen_quality).sort((a, b) => a - b);
  const weakCut = qs[Math.floor(qs.length * 2 / 3)];
  const strongCut = qs[Math.floor(qs.length / 3)];

  const subsets = {
    // The order's concentrated subset.
    concentrated_early_x_weak_pen: all.filter((r) => r.early && r.pen_quality >= weakCut),
    // The mirror, where the descriptive pass suggested the larger movement.
    mirror_early_x_strong_pen: all.filter((r) => r.early && r.pen_quality <= strongCut),
    // Every later at-bat with an early-exit flag, both directions of pen quality.
    all_early_exit_later_abs: all.filter((r) => r.early),
    pooled_all_later_abs: all,
  };

  let cumulative = 1;
  try {
    const sb = createClient(process.env.SUPABASE_URL,
      process.env.SUPABASE_SERVICE_ROLE_KEY || process.env.SUPABASE_SERVICE_KEY,
      { auth: { persistSession: false } });
    const mc = await tl.recordAndCount(tl.supabaseStore(sb), Object.keys(subsets).map((k) => ({
      sport: 'mlb', stat: 'hits', archetype: null,
      interaction: `collapsed_sequence:${k}`, target: 'later_ab_outcome',
    })));
    cumulative = mc.cumulative_tests;
  } catch { /* offline */ }

  const gate = (rs, label) => fg.adjudicate(
    rs.map((r) => ({ cluster: r.cluster, baseline: r.hitter_base, conditioned: adjust(r), won: r.won }))
      .filter((r) => r.conditioned !== null),
    { factor: label, stat: 'hits', cumulativeTests: cumulative },
  );

  const results = {};
  for (const [k, rs] of Object.entries(subsets)) results[k] = gate(rs, k);

  // Hitter split as a SEPARATE gated addition — never assumed into the main effect.
  const conc = subsets.concentrated_early_x_weak_pen;
  const hrs = conc.map((r) => r.hitter_hr_rate).sort((a, b) => a - b);
  const hrCut = hrs[Math.floor(hrs.length / 2)];
  const bySplit = {
    power_hitters: gate(conc.filter((r) => r.hitter_hr_rate >= hrCut), 'concentrated_power'),
    contact_hitters: gate(conc.filter((r) => r.hitter_hr_rate < hrCut), 'concentrated_contact'),
  };

  console.log(JSON.stringify({
    later_at_bats_readable: all.length,
    cumulative_tests: cumulative,
    subset_sizes: Object.fromEntries(Object.entries(subsets).map(([k, v]) => [k, v.length])),
    gate: Object.fromEntries(Object.entries(results).map(([k, v]) => [k, {
      n: v.movement.n,
      clusters: v.improvement ? v.improvement.effective_n : null,
      mean_abs_shift: v.movement.mean_abs_shift,
      brier_delta: v.improvement ? v.improvement.brier_delta : null,
      ci: v.improvement ? v.improvement.ci : null,
      verdict: v.verdict,
    }])),
    hitter_split_separate_gate: Object.fromEntries(Object.entries(bySplit).map(([k, v]) => [k, {
      n: v.movement.n, brier_delta: v.improvement ? v.improvement.brier_delta : null,
      ci: v.improvement ? v.improvement.ci : null, verdict: v.verdict,
    }])),
    refused: {
      pen_archetype: 'did not prove at the corrected bar — excluded from the adjustment',
      hitter_approach_identity: 'SPRAY / fastball-hunter identities do not exist in this registry',
      link3_per_reliever: 'SKIPPED — reliever identity is genuine baseball unpredictability',
    },
  }, null, 2));
  process.exit(0);
})();