routes/fairness.js

const router = require('express').Router();
const StrikeHistory = require('../models/StrikeHistory');
const crypto = require('crypto');

// PUBLIC — no verify middleware
router.get('/verify/:date', async (req, res) => {
  try {
    const dayStart = new Date(req.params.date);
    dayStart.setHours(0,0,0,0);

    const dayEnd = new Date(dayStart);
    dayEnd.setHours(23,59,59,999);

    const strike = await StrikeHistory.findOne({
      date: { $gte: dayStart, $lte: dayEnd }
    }).lean();

    if (!strike) {
      return res.status(404).json({ error: 'No strike found for this date' });
    }

    // Recompute hash
    const recomputedHash = crypto
      .createHash('sha256')
      .update(JSON.stringify(strike.audit_payload))
      .digest('hex');

    res.json({
      date: strike.date,
      target_price: strike.target_price,
      winning_digits: strike.winning_digits,
      audit_hash: strike.audit_hash,
      recomputed_hash: recomputedHash,
      is_valid: recomputedHash === strike.audit_hash,
      audit_payload: strike.audit_payload,
      winners: strike.winners.map(w => ({
        tier: w.tier,
        amount: w.amount,
        rank: w.rank,
        kus_id: w.kus_id
      }))
    });

  } catch (err) {
    console.log(err);
    res.status(500).json({ error: 'Verification failed' });
  }
});

module.exports = router;