// Translatable strings for invoice rendering. Two languages: de (default), en.

export type InvoiceLanguage = "de" | "en";

export interface InvoiceStrings {
  invoice: string;
  stornoInvoice: string;
  offer: string;
  offerNumber: string;
  offerDate: string;
  offerValidUntil: (until: string) => string;
  stornoReference: (originalNumber: string) => string;
  invoiceNumber: string;
  invoiceDate: string;
  deliveryDate: string;
  customerVatId: string;
  position: string;
  description: string;
  quantity: string;
  unitPrice: string;
  totalPrice: string;
  netTotal: string;
  vatLine: (ratePct: string) => string;
  grossTotal: string;
  salutationGeneric: string;
  thankYouLine: string;
  closing: string;
  paymentTerms: (days: number, dueDate: string) => string;
  paymentTermsImmediate: string;
  giroCodeCaption: string;
  reverseChargeNotice: string;
  exportNotice: string;
  kleinunternehmerNotice: string;
  pieceUnit: string;
  page: (current: number, total: number) => string;
  legalCourtLabel: string;
  fnLabel: string;
  vatIdLabel: string;
  taxNumberLabel: string;
  ownerLabel: string;
  ibanLabel: string;
  bicLabel: string;
  bankLabel: string;
  recipientLabel: string;
  amountLabel: string;
  referenceLabel: string;
  /** Label for the refund row that appears below `grossTotal` when the
   *  order has been (partially or fully) refunded. Mirrors what Shopify
   *  shows on the order page ("Zurückerstattet" / "Refunded"). */
  refundedLabel: string;
  /** Label for the final outstanding balance row (`grossTotal -
   *  refundedAmount`) shown when there has been a refund. "Offener
   *  Betrag" / "Outstanding amount". */
  outstandingLabel: string;
  /** Label used in place of `outstandingLabel` when the order has been
   *  refunded but nothing is actually owed any more (i.e. the customer
   *  paid in full and got back only part — or all — of the gross via
   *  refunds). "Endbetrag" / "Total". The distinction matters for
   *  PARTIALLY_REFUNDED orders, where calling the kept portion
   *  "outstanding" would falsely suggest the customer still owes it. */
  finalAmountLabel: string;
  addressHeading: string;
  contactHeading: string;
  legalHeading: string;
  bankHeading: string;
  emailLabel: string;
  webLabel: string;
  phoneLabel: string;
  paymentMethodLabel: string;
  paymentStatusLabel: string;
  paymentStatusPaid: string;
  paymentStatusUnpaid: string;
  paymentStatusPartial: string;
  paymentStatusRefunded: string;
  paymentStatusVoided: string;
  orderNumberLabel: string;
  shippingAddressHeading: string;
  shippingMethodLabel: string;
  trackingLabel: string;
  shippingItemPrefix: string;
  discountCodeLabel: string;
  pickupLabel: string;
  /** Used as the meta-row label when the order is a local pickup. The row
   *  value is then the pickup location name (e.g. "Lager Graz"). */
  pickupLocationLabel: string;
  /** Localized labels for Shopify's built-in payment-gateway names. The
   *  Admin GraphQL API only ever returns the *English* template name
   *  (e.g. "Bank Deposit") in `Order.paymentGatewayNames`, even when the
   *  storefront / order-confirmation page renders the localized variant
   *  ("Banküberweisung"). We mirror Shopify's checkout copy here so the
   *  printed PDF matches what the customer saw at checkout. Lookup is
   *  case-insensitive on the normalized key (lowercased, separators
   *  collapsed). Unknown gateways fall back to a title-cased rendering
   *  of the raw name. */
  paymentGatewayLabels: Record<string, string>;
}

/** Status displayed for the order's payment, derived from Shopify's
 *  `displayFinancialStatus`. */
export type PaymentStatus =
  | "paid"
  | "unpaid"
  | "partial"
  | "refunded"
  | "voided";

export function paymentStatusLabel(
  status: PaymentStatus,
  strings: InvoiceStrings,
): string {
  switch (status) {
    case "paid":
      return strings.paymentStatusPaid;
    case "partial":
      return strings.paymentStatusPartial;
    case "refunded":
      return strings.paymentStatusRefunded;
    case "voided":
      return strings.paymentStatusVoided;
    default:
      return strings.paymentStatusUnpaid;
  }
}

/** Maps Shopify's `displayFinancialStatus` to our condensed enum.
 *
 *  - PAID                                  → paid
 *  - PARTIALLY_PAID                        → partial
 *  - REFUNDED / PARTIALLY_REFUNDED         → refunded
 *    (composeInvoice further reclassifies PARTIALLY_REFUNDED with a
 *    refund < gross back to "paid".)
 *  - VOIDED                                → voided
 *    (authorisation cancelled before capture; no money was ever
 *    received and none is owed — distinct from "unpaid".)
 *  - PENDING / AUTHORIZED / EXPIRED / unknown → unpaid
 *
 *  Unknown values log a warning so we notice when Shopify adds a new
 *  enum member. */
export function derivePaymentStatus(
  displayFinancialStatus: string | null | undefined,
): PaymentStatus {
  const v = (displayFinancialStatus || "").toUpperCase();
  if (v === "PAID") return "paid";
  if (v === "PARTIALLY_PAID") return "partial";
  if (v === "REFUNDED" || v === "PARTIALLY_REFUNDED") return "refunded";
  if (v === "VOIDED") return "voided";
  if (v && v !== "PENDING" && v !== "AUTHORIZED" && v !== "EXPIRED") {
    console.warn(
      `[invoice] derivePaymentStatus: unknown displayFinancialStatus ${JSON.stringify(
        displayFinancialStatus,
      )} — falling back to "unpaid".`,
    );
  }
  return "unpaid";
}

const de: InvoiceStrings = {
  invoice: "Rechnung",
  stornoInvoice: "Stornorechnung",
  offer: "Angebot",
  offerNumber: "Angebots-Nr.",
  offerDate: "Angebotsdatum",
  offerValidUntil: (d) => `Dieses Angebot ist gültig bis ${d}.`,
  stornoReference: (n) => `Storno zu Rechnung Nr. ${n}`,
  invoiceNumber: "Rechnungs-Nr.",
  invoiceDate: "Rechnungsdatum",
  deliveryDate: "Lieferdatum",
  customerVatId: "Deine USt-Id.",
  position: "Pos.",
  description: "Beschreibung",
  quantity: "Menge",
  unitPrice: "Einzelpreis",
  totalPrice: "Gesamtpreis",
  netTotal: "Gesamtbetrag netto",
  vatLine: (r) => `zzgl. Umsatzsteuer ${r}`,
  grossTotal: "Gesamtbetrag brutto",
  salutationGeneric: "Hallo,",
  thankYouLine:
    "Vielen Dank für deine Bestellung. Wir berechnen dir folgende Leistungen:",
  closing: "Danke für deinen Einkauf",
  paymentTerms: (days, due) =>
    `Bitte überweise den Rechnungsbetrag innerhalb von ${days} Tagen, spätestens bis zum ${due}, auf das unten angegebene Konto. Bei Fragen zur Rechnung sind wir gerne für dich da.`,
  paymentTermsImmediate:
    "Der Rechnungsbetrag ist sofort nach Erhalt zur Zahlung fällig.",
  giroCodeCaption: "GiroCode",
  reverseChargeNotice:
    "Steuerschuldnerschaft des Leistungsempfängers gemäß Art. 196 MwStSystRL (Reverse Charge).",
  exportNotice: "Steuerfreie Ausfuhrlieferung gemäß § 7 UStG.",
  kleinunternehmerNotice:
    "Gemäß § 6 Abs. 1 Z 27 UStG wird keine Umsatzsteuer ausgewiesen (Kleinunternehmer).",
  pieceUnit: "Stk",
  page: (c, t) => `${c}/${t}`,
  legalCourtLabel: "Amtsgericht",
  fnLabel: "FN",
  vatIdLabel: "UID",
  taxNumberLabel: "St.Nr.",
  ownerLabel: "Inhaber",
  ibanLabel: "IBAN",
  bicLabel: "BIC",
  bankLabel: "Bank",
  recipientLabel: "Empfänger",
  amountLabel: "Betrag",
  referenceLabel: "Referenz",
  refundedLabel: "Zurückerstattet",
  outstandingLabel: "Offener Betrag",
  finalAmountLabel: "Endbetrag",
  addressHeading: "Adresse",
  contactHeading: "Kontakt",
  legalHeading: "Rechtliches",
  bankHeading: "Bankverbindung",
  emailLabel: "E-Mail",
  webLabel: "Web",
  phoneLabel: "Tel.",
  paymentMethodLabel: "Zahlart",
  paymentStatusLabel: "Zahlstatus",
  paymentStatusPaid: "Bezahlt",
  paymentStatusUnpaid: "Offen",
  paymentStatusPartial: "Teilweise bezahlt",
  paymentStatusRefunded: "Erstattet",
  paymentStatusVoided: "Annulliert",
  orderNumberLabel: "Bestellnummer",
  shippingAddressHeading: "Lieferadresse",
  shippingMethodLabel: "Versandart",
  trackingLabel: "Sendungsnummer",
  shippingItemPrefix: "Versand",
  discountCodeLabel: "Rabattcode",
  pickupLabel: "Abholung",
  pickupLocationLabel: "Abholort",
  paymentGatewayLabels: {
    // Built-in Shopify manual payment methods (template names).
    "bank deposit": "Banküberweisung",
    "bank transfer": "Banküberweisung",
    "money order": "Postanweisung",
    "cash on delivery": "Nachnahme",
    "cash on delivery (cod)": "Nachnahme",
    // Generic / technical gateways.
    manual: "Manuelle Zahlung",
    bogus: "Bogus (Test)",
    "shopify payments": "Shopify Payments",
    paypal: "PayPal",
    "paypal express checkout": "PayPal",
    klarna: "Klarna",
    sofort: "Sofort",
    giropay: "Giropay",
  },
};

const en: InvoiceStrings = {
  invoice: "Invoice",
  stornoInvoice: "Cancellation invoice",
  offer: "Offer",
  offerNumber: "Offer no.",
  offerDate: "Offer date",
  offerValidUntil: (d) => `This offer is valid until ${d}.`,
  stornoReference: (n) => `Cancels invoice no. ${n}`,
  invoiceNumber: "Invoice no.",
  invoiceDate: "Invoice date",
  deliveryDate: "Delivery date",
  customerVatId: "Your VAT ID",
  position: "Pos.",
  description: "Description",
  quantity: "Qty",
  unitPrice: "Unit price",
  totalPrice: "Total",
  netTotal: "Net total",
  vatLine: (r) => `plus VAT ${r}`,
  grossTotal: "Gross total",
  salutationGeneric: "Dear Sir or Madam,",
  thankYouLine:
    "Thank you for your order. We hereby invoice you for the following:",
  closing: "Thank you for your purchase.",
  paymentTerms: (days, due) =>
    `Please transfer the invoice amount within ${days} days, no later than ${due}, to the bank account shown below.`,
  paymentTermsImmediate: "The invoice amount is due immediately upon receipt.",
  giroCodeCaption: "GiroCode",
  reverseChargeNotice:
    "Reverse charge: VAT to be accounted for by the recipient pursuant to Art. 196 of Council Directive 2006/112/EC.",
  exportNotice: "Tax-exempt export delivery pursuant to § 7 UStG.",
  kleinunternehmerNotice:
    "VAT is not charged pursuant to § 6 (1) 27 UStG (small-business exemption).",
  pieceUnit: "pcs",
  page: (c, t) => `${c}/${t}`,
  legalCourtLabel: "Commercial court",
  fnLabel: "FN",
  vatIdLabel: "VAT ID",
  taxNumberLabel: "Tax no.",
  ownerLabel: "Owner",
  ibanLabel: "IBAN",
  bicLabel: "BIC",
  bankLabel: "Bank",
  recipientLabel: "Recipient",
  amountLabel: "Amount",
  referenceLabel: "Reference",
  refundedLabel: "Refunded",
  outstandingLabel: "Outstanding amount",
  finalAmountLabel: "Total",
  addressHeading: "Address",
  contactHeading: "Contact",
  legalHeading: "Legal",
  bankHeading: "Bank details",
  emailLabel: "E-mail",
  webLabel: "Web",
  phoneLabel: "Tel.",
  paymentMethodLabel: "Payment method",
  paymentStatusLabel: "Payment status",
  paymentStatusPaid: "Paid",
  paymentStatusUnpaid: "Outstanding",
  paymentStatusPartial: "Partially paid",
  paymentStatusRefunded: "Refunded",
  paymentStatusVoided: "Voided",
  orderNumberLabel: "Order no.",
  shippingAddressHeading: "Shipping address",
  shippingMethodLabel: "Shipping method",
  trackingLabel: "Tracking no.",
  shippingItemPrefix: "Shipping",
  discountCodeLabel: "Discount code",
  pickupLabel: "Pick-up",
  pickupLocationLabel: "Pick-up location",
  paymentGatewayLabels: {
    "bank deposit": "Bank deposit",
    "bank transfer": "Bank transfer",
    "money order": "Money order",
    "cash on delivery": "Cash on delivery",
    "cash on delivery (cod)": "Cash on delivery (COD)",
    manual: "Manual",
    bogus: "Bogus (Test)",
    "shopify payments": "Shopify Payments",
    paypal: "PayPal",
    "paypal express checkout": "PayPal",
    klarna: "Klarna",
    sofort: "Sofort",
    giropay: "Giropay",
  },
};

// Locale → invoice language. We only render in German (`de`) when the
// caller is explicitly German-speaking (de, de-AT, de-DE, de_CH, …).
// Everything else (it, fr, es, en, …) falls back to English so that
// non-German-speaking customers don't receive a German invoice. Callers
// that have a per-shop default fall back to it via
// `pickLanguage(customerLocale ?? settings.defaultLanguage)`, which is why
// `null`/`undefined` still maps to `de` (the legacy default for the
// Austrian shops this app was built for).
export function pickLanguage(input: string | null | undefined): InvoiceLanguage {
  if (!input) return "de";
  const v = input.toLowerCase();
  if (v.startsWith("de")) return "de";
  return "en";
}

export function getStrings(language: InvoiceLanguage): InvoiceStrings {
  return language === "en" ? en : de;
}