// evaluates predictions older than 11 days against realized stock returns
// runs continuously, batching by ticker so we hit yahoo once per company per cycle

const { getPriceContext } = require("./priceContext");
const https = require("https");


async function runOutcomeWorker(archiveDb, intelligenceDb, config) {
  const loopDelay = config.workers?.outcomeLoopDelayMs ?? 60000;

  // pull predictions that are old enough to evaluate (>= 11 calendar days) and dont have an outcome yet
  const getPending = intelligenceDb.prepare(`
    SELECT ep.id, ep.company_id, ep.event_date, ep.direction, tc.ticker
    FROM event_predictions ep
    JOIN tracked_companies tc ON ep.company_id = tc.id
    LEFT JOIN prediction_outcomes po ON po.prediction_id = ep.id
    WHERE po.prediction_id IS NULL
      AND ep.event_date IS NOT NULL
      AND date(ep.event_date) <= date('now', '-11 days')
      AND ep.direction IN ('positive', 'negative')
      AND tc.ticker IS NOT NULL
      AND tc.ticker NOT LIKE '%.%'
      AND length(tc.ticker) <= 5
    ORDER BY ep.event_date ASC
    LIMIT 50
  `);

  const insertOutcome = intelligenceDb.prepare(`
    INSERT OR REPLACE INTO prediction_outcomes
      (prediction_id, company_id, ticker, event_date, price_0, price_5d, price_10d, r5, r10, correct_5d, correct_10d)
    VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
  `);

  while (true) {
    try {
      const pending = getPending.all();

      if (pending.length === 0) {
        await sleep(loopDelay);
        continue;
      }

      // group by ticker so we only fetch each company's history once per cycle
      const byTicker = new Map();
      for (const p of pending) {
        if (!byTicker.has(p.ticker)) byTicker.set(p.ticker, []);
        byTicker.get(p.ticker).push(p);
      }

      let evaluated = 0;
      for (const [ticker, preds] of byTicker.entries()) {
        let history;
        try {
          history = await fetchYahooHistory(ticker, "1y");
        } catch (err) {
          console.error(`[outcome] yahoo error for ${ticker}: ${err.message}`);
          continue;
        }

        if (!history || history.length === 0) continue;

        for (const pred of preds) {
          const eventDate = pred.event_date.slice(0, 10);
          const price0 = nearestOnOrAfter(history, eventDate);
          if (price0 == null) continue;

          const date5 = addTradingDays(eventDate, 5);
          const date10 = addTradingDays(eventDate, 10);
          const price5 = nearestOnOrAfter(history, date5);
          const price10 = nearestOnOrAfter(history, date10);

          const r5 = price5 != null ? (price5 - price0) / price0 * 100 : null;
          const r10 = price10 != null ? (price10 - price0) / price0 * 100 : null;

          const correct5 = r5 == null ? null : (pred.direction === "positive" ? (r5 > 0 ? 1 : 0) : (r5 < 0 ? 1 : 0));
          const correct10 = r10 == null ? null : (pred.direction === "positive" ? (r10 > 0 ? 1 : 0) : (r10 < 0 ? 1 : 0));

          insertOutcome.run(
            pred.id, pred.company_id, ticker, eventDate,
            price0, price5, price10, r5, r10, correct5, correct10
          );
          evaluated++;
        }

        // small delay between tickers so we dont hammer yahoo
        await sleep(800);
      }

      if (evaluated > 0) {
        console.log(`[outcome] evaluated ${evaluated} predictions across ${byTicker.size} tickers`);
      }

      await sleep(loopDelay);

    } catch (err) {
      console.error("[outcome] cycle error:", err.message);
      await sleep(loopDelay);
    }
  }
}


async function fetchYahooHistory(ticker, range) {
  const url = `https://query1.finance.yahoo.com/v8/finance/chart/${encodeURIComponent(ticker)}?range=${range}&interval=1d`;
  const body = await httpGet(url, { "User-Agent": "Mozilla/5.0 (compatible; duriin-intelligence/1.0)" });

  const parsed = JSON.parse(body);
  const result = parsed?.chart?.result?.[0];
  if (!result) return null;

  const ts = result.timestamp || [];
  const closes = result.indicators?.quote?.[0]?.close || [];

  const out = [];
  for (let i = 0; i < ts.length; i++) {
    if (closes[i] == null) continue;
    out.push({
      date: new Date(ts[i] * 1000).toISOString().slice(0, 10),
      close: closes[i],
    });
  }
  return out;
}


function nearestOnOrAfter(history, dateStr) {
  for (const row of history) {
    if (row.date >= dateStr) return row.close;
  }
  return null;
}


function addTradingDays(dateStr, n) {
  const dt = new Date(dateStr);
  let count = 0;
  while (count < n) {
    dt.setDate(dt.getDate() + 1);
    const dow = dt.getDay();
    if (dow >= 1 && dow <= 5) count++;
  }
  return dt.toISOString().slice(0, 10);
}


function httpGet(url, headers) {
  return new Promise((resolve, reject) => {
    const u = new URL(url);
    const req = https.request({
      hostname: u.hostname,
      path: u.pathname + u.search,
      method: "GET",
      headers,
    }, (res) => {
      let data = "";
      res.on("data", chunk => data += chunk);
      res.on("end", () => {
        if (res.statusCode >= 200 && res.statusCode < 300) resolve(data);
        else reject(new Error(`yahoo ${res.statusCode}: ${data.slice(0, 200)}`));
      });
    });
    req.on("error", reject);
    req.end();
  });
}


function sleep(ms) {
  return new Promise(r => setTimeout(r, ms));
}


module.exports = { runOutcomeWorker };