// @ts-check
// Pure decision logic, kept separate from the run.js adapter so it's
// unit-testable directly with plain Vitest (see
// tests/unit/payment-customization.test.ts at the repo root) with no WASM
// build.
//
// Study §5.2 / DS parity: "payment options can be adjusted based on the
// fulfillment method chosen — e.g. hiding cash-on-delivery for a shipped
// order." A shipped order leaves the store before it's paid in person, so
// cash-on-delivery / pay-in-store gateways make no sense for it; pickup and
// local delivery keep every method.

/** Matches the common names Shopify merchants give manual "pay later / in person" gateways. */
export const DEFAULT_HIDE_PATTERN = /cash on delivery|\bc\.?o\.?d\.?\b|pay on delivery|pay on pickup|pay in store|pay in person/i;

/**
 * @param {Record<string, string | null | undefined>} attributes  The cart's dd_* attributes.
 * @param {string[]} paymentMethodNames  Names of every payment method offered at checkout.
 * @param {{ pattern?: RegExp }} [options]
 * @returns {string[]} the subset of `paymentMethodNames` that should be hidden.
 */
export function paymentMethodNamesToHide(attributes, paymentMethodNames, options = {}) {
  const pattern = options.pattern ?? DEFAULT_HIDE_PATTERN;

  // Only shipped orders lose the pay-in-person options. No selection yet, or
  // pickup/local delivery → touch nothing.
  if (attributes.dd_method !== "SHIPPING") return [];

  return paymentMethodNames.filter((name) => typeof name === "string" && pattern.test(name));
}