/** Platzhalter bis ZKA-Produktregistrierung vorliegt – Bank kann ablehnen, Config-Check bricht nicht ab. */
export const FINTS_PRODUCT_ID_PLACEHOLDER = "XXXXX";

export type FintsConfigStatus = {
  ready: boolean;
  missing: string[];
  warnings: string[];
  usesProductIdPlaceholder: boolean;
};

export function getFintsConfigStatus(overrides?: {
  blz?: string;
  url?: string;
  login?: string;
  productId?: string;
  pin?: string;
}): FintsConfigStatus {
  const url = overrides?.url || process.env.FINTS_BANK_URL || "";
  const blz = overrides?.blz || process.env.FINTS_BANK_BLZ || "";
  const login = overrides?.login || process.env.FINTS_USER_ID || "";
  const pin = overrides?.pin || process.env.FINTS_PIN || "";
  const productId = overrides?.productId || process.env.FINTS_PRODUCT_ID || "";

  const missing: string[] = [];
  if (!url) missing.push("FinTS-URL");
  if (!blz) missing.push("BLZ");
  if (!login) missing.push("Zugangsnummer");
  if (!pin) missing.push("PIN");

  const warnings: string[] = [];
  const usesProductIdPlaceholder = !productId;
  if (usesProductIdPlaceholder) {
    warnings.push(
      "Produkt-ID (ZKA) noch nicht gesetzt – Sync wird versucht, die Bank kann die Anfrage ablehnen.",
    );
  }

  return {
    ready: missing.length === 0,
    missing,
    warnings,
    usesProductIdPlaceholder,
  };
}

export function resolveFintsEnvFields(overrides?: {
  blz?: string;
  url?: string;
  login?: string;
  productId?: string;
  productVersion?: string;
  pin?: string;
}): {
  productId: string;
  productVersion: string;
  url: string;
  blz: string;
  login: string;
  pin: string;
  usesProductIdPlaceholder: boolean;
} {
  const status = getFintsConfigStatus(overrides);
  if (!status.ready) {
    throw new Error(
      `FinTS-Zugang unvollständig: ${status.missing.join(", ")} fehlt. Bitte in Convex-Env oder Einstellungen ergänzen.`,
    );
  }

  const productId =
    overrides?.productId || process.env.FINTS_PRODUCT_ID || FINTS_PRODUCT_ID_PLACEHOLDER;

  return {
    productId,
    productVersion: overrides?.productVersion || process.env.FINTS_PRODUCT_VERSION || "1.0.0",
    url: overrides?.url || process.env.FINTS_BANK_URL || "",
    blz: overrides?.blz || process.env.FINTS_BANK_BLZ || "",
    login: overrides?.login || process.env.FINTS_USER_ID || "",
    pin: overrides?.pin || process.env.FINTS_PIN || "",
    usesProductIdPlaceholder: status.usesProductIdPlaceholder,
  };
}