/**
 * Prepaid mutations. Account-balance is the writer when NATS or HTTP books exist.
 * Tests (no NATS_URL, no ACCOUNT_BALANCE_URL) keep a local cache only.
 */
import { natsAdjust, natsPublish, natsStatement } from './billing-nats';
import type { AccessPlane } from './billing-nats';

export type PrepaidRow = {
  customerId: string;
  veraeUserId?: string;
  cents: number;
  reason: string;
  agent: string;
  kind?: string;
  prepaidCents?: number;
};

function booksUrl(): string {
  return (process.env.ACCOUNT_BALANCE_URL || '').replace(/\/$/, '');
}

export function booksConfigured(): boolean {
  return Boolean(process.env.NATS_URL || booksUrl());
}

export async function ledgerAdjust(row: PrepaidRow, plane: AccessPlane): Promise<PrepaidRow | null> {
  const viaNats = await natsAdjust(row, plane);
  if (viaNats && typeof viaNats === 'object' && viaNats !== null && 'prepaidCents' in viaNats) {
    return viaNats as PrepaidRow;
  }
  const base = booksUrl();
  if (!base) return null;
  const r = await fetch(`${base}/adjust`, {
    method: 'POST',
    headers: { 'content-type': 'application/json' },
    body: JSON.stringify(row),
  });
  if (!r.ok) return null;
  return (await r.json()) as PrepaidRow;
}

export async function ledgerPutCustomer(row: {
  customerId: string;
  name?: string;
  veraeUserId?: string;
}): Promise<void> {
  natsPublish('verae.billing.customer.put', row, 'staff');
  const base = booksUrl();
  if (!base) return;
  await fetch(`${base}/customer`, {
    method: 'POST',
    headers: { 'content-type': 'application/json' },
    body: JSON.stringify(row),
  }).catch(() => {});
}

export async function ledgerStatement(customerId: string, plane: AccessPlane, veraeUserId?: string) {
  const nats = await natsStatement(customerId, plane, veraeUserId);
  if (nats) return nats;
  const base = booksUrl();
  if (!base) return null;
  const r = await fetch(`${base}/statement/${encodeURIComponent(customerId)}`);
  if (!r.ok) return null;
  return r.json();
}