/* Commons product flags pricing protocol v1. Hosts own price rendering and lifecycle. */
(function (global) {
  'use strict';

  function evaluate(root, context, apply) {
    if (!root || typeof root.querySelectorAll !== 'function' || typeof apply !== 'function') return null;

    var flags = Array.prototype.filter.call(root.querySelectorAll('[data-pf-p]'), function (flag) {
      return flag.closest('[data-pf-root]') === root;
    });
    flags.forEach(function (flag) { flag.removeAttribute('data-pf-active'); });

    var cents = context && context.priceCents;
    var valid = context && context.coverage === true && Number.isSafeInteger(cents) && cents > 0;
    var winner = null;
    var finalCents = cents;

    if (valid) {
      flags.forEach(function (flag) {
        var raw = flag.getAttribute('data-pf-p');
        if (typeof raw !== 'string' || raw.length > 32 || !/^\d+(?:\.\d+)?$/.test(raw)) return;
        var parts = raw.split('.');
        if (parts[1] && parts[1].length > 18) return;
        var denominator = 10n ** BigInt(parts[1] ? parts[1].length : 0);
        var numerator = BigInt(parts.join(''));
        var divisor = 100n * denominator;
        if (numerator <= 0n || numerator >= divisor) return;
        // Half-up in integer cents, without floating-point half-cent drift.
        var reduction = Number((BigInt(cents) * numerator + divisor / 2n) / divisor);
        var candidate = cents - reduction;
        if (candidate <= 0 || candidate >= cents) return;
        // Stable DOM order wins a tie; every candidate uses the same original cents.
        if (winner === null || candidate < finalCents) {
          winner = flag;
          finalCents = candidate;
        }
      });
    }

    var result = valid && winner ? {
      finalCents: finalCents, originalCents: cents, variantId: context.variantId
    } : null;
    try {
      if (apply(result) !== true) {
        if (result) apply(null);
        return null;
      }
    } catch (_) {
      try { apply(null); } catch (_) { /* Host must keep native price on failure. */ }
      return null;
    }
    if (result && root.isConnected === false) {
      try { apply(null); } catch (_) { /* Removed scopes cannot expose a winner. */ }
      return null;
    }
    if (result) winner.setAttribute('data-pf-active', '');
    return result;
  }

  global.CommonsFlagsPricing = Object.freeze({ version: 1, evaluate: evaluate });
  if (global.document) global.document.dispatchEvent(new Event('commons-flags-pricing:ready'));
})(window);