const AUTHZ = (process.env.AUTHZ_URL || 'http://127.0.0.1:3020').replace(/\/$/, '');
const BOOKS = (process.env.ACCOUNT_BALANCE_URL || 'http://127.0.0.1:3010').replace(/\/$/, '');

export const PLANE = 'web';
export const AUTHZ_CHECK = 'verae.access.authz.check';

export async function check(subject, { principal, kind, payload } = {}) {
  const r = await fetch(`${AUTHZ}/check`, {
    method: 'POST',
    headers: { 'content-type': 'application/json' },
    body: JSON.stringify({ plane: PLANE, subject, principal, kind, payload }),
  });
  return { status: r.status, body: await r.json().catch(() => ({ allow: false })) };
}

export async function statement(customerId, principal) {
  const gate = await check('verae.billing.statement.get', { principal });
  if (!gate.body.allow) return { status: 403, body: gate.body };
  const url = process.env.NATS_URL;
  if (url) {
    try {
      const { connect, StringCodec } = await import('nats');
      const nc = await connect({ servers: url.split(','), name: 'verae-access-web' });
      const sc = StringCodec();
      const m = await nc.request(
        'verae.billing.statement.get',
        sc.encode(JSON.stringify({ customerId, plane: PLANE, principal })),
        { timeout: 2000 },
      );
      const out = JSON.parse(sc.decode(m.data) || '{}');
      await nc.close();
      return { status: 200, body: { ...out, source: 'nats', plane: PLANE } };
    } catch {
      /* HTTP fallback */
    }
  }
  const r = await fetch(`${BOOKS}/statement/${customerId}`);
  return { status: r.status, body: { ...(await r.json().catch(() => ({}))), source: 'account-balance', plane: PLANE } };
}

export async function reload(customerId, cents, principal) {
  const gate = await check('verae.billing.balance.adjust', { principal, kind: 'reload' });
  if (!gate.body.allow) return { status: 403, body: gate.body };
  const r = await fetch(`${BOOKS}/adjust`, {
    method: 'POST',
    headers: { 'content-type': 'application/json' },
    body: JSON.stringify({ customerId, cents, reason: 'reload', agent: principal || 'web', kind: 'reload' }),
  });
  return { status: r.status, body: { ...(await r.json().catch(() => ({}))), plane: PLANE } };
}