'use strict';

/**
 * DEDUPE PARITY — old key vs new key on REAL prop shapes.
 *
 * The event-aware dedupe changes candidate identity, so a single champion
 * probability check is not sufficient evidence that ordinary slates are
 * unaffected. This replays BOTH keys over real prop shapes reconstructed from
 * production rows and reports every difference.
 *
 * Writes nothing. Deterministic.
 *
 *   PARITY_DATE=2026-08-26 node scripts/dedupe-parity.js
 */

const { createClient } = require('@supabase/supabase-js');
const { paginate } = require('../src/utils/safePaginate');
const E = require('../src/services/event/eventIdentity');

const SPORT = process.env.PARITY_SPORT || 'mlb';
const DATE = process.env.PARITY_DATE || '2026-08-26';

function client() {
  const url = process.env.SUPABASE_URL;
  const key = process.env.SUPABASE_SERVICE_KEY || process.env.SUPABASE_SERVICE_ROLE_KEY;
  if (!url || !key) throw new Error('SUPABASE_URL + service key required');
  return createClient(url, key, { auth: { persistSession: false } });
}

/** The OLD key, verbatim: player::stat_type::line. */
const oldKey = (p) => `${p.player}::${p.stat_type}::${p.line}`;

/** The NEW key: event leads. */
function newKey(p) {
  const ev = p.canonical_event_id
    || (p.event_identity_method && p.event_identity_method !== 'UNSUPPORTED_SPORT'
      ? `unresolved-event:${p.event_identity_method}:${p.__row}`
      : `legacy:${p.game_date}:${String(p.away_team || '').replace(/\s+/g, '')}@${String(p.home_team || '').replace(/\s+/g, '')}`);
  return `${ev}::${p.player}::${p.stat_type}::${p.line}`;
}

function teamsFromGameId(gameId) {
  const tail = String(gameId || '').split(':').pop();
  const [away, home] = String(tail).split('@');
  return { away_team: away || null, home_team: home || null };
}

async function main() {
  const sb = client();
  const rows = await paginate(
    () => sb.from('model_snapshots')
      .select('id, player_name, player_key, stat, line, side, game_id, game_date, book')
      .eq('sport', SPORT).eq('game_date', DATE),
    { key: 'id', label: 'model_snapshots:dedupe-parity' },
  );

  // Schedule + rosters straight from statsapi (free, no cache layer) so the
  // replay does not depend on Redis being reachable.
  const sched = await (await fetch(`https://statsapi.mlb.com/api/v1/schedule?sportId=1&date=${DATE}`)).json();
  const games = (sched.dates || []).flatMap((d) => d.games || []).map((g) => ({
    gamePk: g.gamePk, gameNumber: g.gameNumber, gameDate: g.gameDate,
    home: { team: g.teams.home.team.name, teamId: g.teams.home.team.id },
    away: { team: g.teams.away.team.name, teamId: g.teams.away.team.id },
  }));

  // PARTICIPANT EVIDENCE — the same index production builds.
  const built = await E.buildPlayerTeamIndex(games, {
    getTeamRoster: async (id) => {
      const r = await (await fetch(`https://statsapi.mlb.com/api/v1/teams/${id}/roster?rosterType=active`)).json();
      return (r.roster || []).map((x) => ({ id: x.person && x.person.id, name: x.person && x.person.fullName }));
    },
  });
  const playerTeams = built.index;

  // Reconstruct prop shapes. One row per (player, stat, line, book) — the side
  // is not part of the dedupe key, so both sides collapse to the same prop.
  const seen = new Set();
  const props = [];
  for (const r of rows) {
    const k = `${r.player_key}|${r.stat}|${r.line}|${r.book}`;
    if (seen.has(k)) continue;
    seen.add(k);
    props.push({
      __row: props.length,
      player: r.player_name || r.player_key,
      stat_type: r.stat,
      line: r.line,
      book: r.book,
      game_date: r.game_date,
      ...teamsFromGameId(r.game_id),
    });
  }
  // The schedule has one game per pair on a non-doubleheader date, so teams
  // alone resolve; no game_time is needed and none is reconstructed.
  const ident = E.attachEventIdentity(SPORT, props, games, playerTeams);

  const oldSet = new Set(props.map(oldKey));
  const newSet = new Set(props.map(newKey));

  // Which OLD keys collapsed rows that the NEW key separates?
  const byOld = new Map();
  for (const p of props) {
    const k = oldKey(p);
    if (!byOld.has(k)) byOld.set(k, new Set());
    byOld.get(k).add(newKey(p));
  }
  const split = [...byOld.entries()].filter(([, s]) => s.size > 1);

  console.log(`\n=== DEDUPE PARITY — ${SPORT} ${DATE} ===`);
  console.log(`snapshot rows read            : ${rows.length}`);
  console.log(`reconstructed prop shapes     : ${props.length}`);
  console.log(`participant evidence          : ${built.stats.players} players / ${built.stats.teams} rosters`);
  console.log(`canonical event resolution    : ${ident.canonical}/${ident.total}`
    + ` (unresolved ${ident.unresolved}, unsupported ${ident.unsupported})`);
  console.log(`IMPOSSIBLE-BINDING refusals   : ${ident.impossible}`);
  if (Object.keys(ident.reasons).length) console.log(`  unresolved reasons          : ${JSON.stringify(ident.reasons)}`);
  console.log(`distinct events               : ${new Set(props.map((p) => p.canonical_event_id).filter(Boolean)).size}`);
  console.log('');
  console.log(`OLD key  -> unique candidates : ${oldSet.size}`);
  console.log(`NEW key  -> unique candidates : ${newSet.size}`);
  console.log(`difference                    : ${newSet.size - oldSet.size}`);
  console.log(`OLD keys the NEW key SPLITS   : ${split.length}`);
  for (const [k, s] of split.slice(0, 5)) {
    console.log(`   ${k}`);
    for (const nk of s) console.log(`      -> ${nk}`);
  }
  console.log('');
  if (split.length === 0) {
    console.log('VERDICT: NO CANDIDATE-UNIVERSE DIFFERENCE on this slate.');
    console.log('  Every old key mapped to exactly one new key, so the event');
    console.log('  component changed nothing here. Expected on a non-doubleheader date.');
  } else {
    console.log('VERDICT: CANDIDATE-UNIVERSE DATA-INTEGRITY CORRECTION.');
    console.log(`  ${split.length} old key(s) collapsed rows from more than one real event.`);
  }
  console.log('');
}

if (require.main === module) {
  main().then(() => process.exit(0)).catch((e) => { console.error('FAILED:', e.message); process.exit(1); });
}
module.exports = { oldKey, newKey };