#!/usr/bin/env node

// PR 1 of the resilience repair plan (§3.1). Writes per-country
// electric power transmission + distribution losses. Read by
// scoreEnergy v2 via `resilience:power-losses:v1` as the direct
// grid-integrity signal that replaces the retired electricityConsumption
// wealth proxy.
//
// Source: World Bank WDI EG.ELC.LOSS.ZS — "Electric power
// transmission and distribution losses (% of output)". Annual
// cadence. Lower is better; developing economies often report 15-25%,
// OECD economies typically 3-8%.

import { loadEnvFile, CHROME_UA, runSeed } from './_seed-utils.mjs';
import iso3ToIso2 from './shared/iso3-to-iso2.json' with { type: 'json' };
// Pure contentMeta + year parser live in their own module so tests can
// import the real code (no replicas, no drift). Per-country annual shape:
// each country reports its own year; newestItemAt = max year across all.
import { powerReliabilityContentMeta, POWER_RELIABILITY_MAX_CONTENT_AGE_MIN } from './_power-reliability-helpers.mjs';

loadEnvFile(import.meta.url);

const WB_BASE = 'https://api.worldbank.org/v2';
const CANONICAL_KEY = 'resilience:power-losses:v1';
const CACHE_TTL = 35 * 24 * 3600;
const INDICATOR = 'EG.ELC.LOSS.ZS';

async function fetchPowerLosses() {
  const pages = [];
  let page = 1;
  let totalPages = 1;
  while (page <= totalPages) {
    // mrv=5 (NOT mrv=1) per memory `feedback_wb_bulk_mrv1_null_coverage_trap`:
    // mrv=1 returns a SINGLE year across all countries with `value: null` for
    // late-reporters (KW/QA/AE publish 1-2y behind G7), silently dropping
    // them. mrv=5 + per-country pickLatest gives a true latest-non-null.
    const url = `${WB_BASE}/country/all/indicator/${INDICATOR}?format=json&per_page=2000&page=${page}&mrv=5`;
    const resp = await fetch(url, {
      headers: { 'User-Agent': CHROME_UA },
      signal: AbortSignal.timeout(30_000),
    });
    if (!resp.ok) throw new Error(`World Bank ${INDICATOR}: HTTP ${resp.status}`);
    const json = await resp.json();
    totalPages = json[0]?.pages ?? 1;
    pages.push(...(json[1] ?? []));
    page++;
  }

  const countries = {};
  for (const record of pages) {
    const rawCode = record?.countryiso3code ?? record?.country?.id ?? '';
    const iso2 = rawCode.length === 3 ? (iso3ToIso2[rawCode] ?? null) : (rawCode.length === 2 ? rawCode : null);
    if (!iso2) continue;
    // CRITICAL: skip null records BEFORE Number() coercion.
    // Number(null) === 0 (not NaN), passes Number.isFinite(), and would
    // let a `value: null` record overwrite an older non-null record below.
    // EG.ELC.LOSS.ZS is a "% of" indicator where 0 IS legitimate (perfect
    // grid reliability), so we CAN'T use the `value <= 0` defense — must
    // skip null explicitly. Same recipe as PR #3427.
    if (record?.value == null) continue;
    const value = Number(record.value);
    if (!Number.isFinite(value)) continue;
    const year = Number(record?.date);
    if (!Number.isFinite(year)) continue;
    // Per-country latest-non-null (mrv=5 returns up to 5 records per country).
    const existing = countries[iso2];
    if (!existing || year > existing.year) {
      countries[iso2] = { value, year };
    }
  }

  return { countries, seededAt: new Date().toISOString() };
}

// Threshold lowered 150 → 100 on 2026-05-03: prior threshold sat at ~70%
// of typical coverage (canonical key carries ~216 countries), so a normal
// WB late-reporter blip that drops the fetch to 149 wholesale-rejected
// the run. validateFn=false → atomicPublish skipped → seed-meta refreshed
// with recordCount=0 (per the "quiet-period feeds" branch in runSeed) →
// /api/health reports EMPTY_DATA even though the canonical key still
// holds last-good 216-country data. 100 keeps a meaningful coverage
// signal (anything below is a real upstream regression) while tolerating
// the day-to-day WB variation in late-publishing economies.
function validate(data) {
  return typeof data?.countries === 'object' && Object.keys(data.countries).length >= 100;
}

export function declareRecords(data) {
  return Object.keys(data?.countries || {}).length;
}

if (process.argv[1]?.endsWith('seed-power-reliability.mjs')) {
  runSeed('resilience', 'power-losses', CANONICAL_KEY, fetchPowerLosses, {
    validateFn: validate,
    ttlSeconds: CACHE_TTL,
    sourceVersion: `wb-power-losses-${new Date().getFullYear()}`,
    recordCount: (data) => Object.keys(data?.countries ?? {}).length,
    declareRecords,
    schemaVersion: 1,
    maxStaleMin: 8 * 24 * 60,

    // ── Content-age contract (Sprint 4 of the 2026-05-04 health-readiness plan) ──
    //
    // 36-month budget = 30mo steady-state ceiling + 6mo slack.
    //
    // The 30mo ceiling comes from the WB publication-lag-plus-cycle math:
    // year N+1 can normally publish as late as end-of-(N+1) + 18mo =
    // end-of-N + 30mo, so a cache holding year N can legitimately reach
    // 30mo of age before year N+1 arrives. Anything tighter than 30mo
    // false-positives mid-cycle. See helper module's JSDoc for the full
    // derivation + the verification against live WB data on 2026-05-05.
    //
    // STALE_CONTENT trips only on multi-cycle silent upstream stalls,
    // never during normal "year N+1 ran late" cycles.
    //
    // powerReliabilityContentMeta scans data.countries per-country years
    // and returns end-of-(max year) UTC ms as newestItemAt.
    contentMeta: powerReliabilityContentMeta,
    maxContentAgeMin: POWER_RELIABILITY_MAX_CONTENT_AGE_MIN,
  }).catch((err) => {
    const _cause = err.cause ? ` (cause: ${err.cause.message || err.cause.code || err.cause})` : '';
    console.error('FATAL:', (err.message || err) + _cause);
    process.exit(1);
  });
}
