/**
 * Choosing the destination number for the manual scripts.
 *
 * 555-01xx numbers are reserved as fictional and do not exist, so they are a
 * fine placeholder for the console adapter and a guaranteed failure against the
 * real API: Twilio validates the destination even under test credentials and
 * answers "The 'To' number ... is not a valid phone number."
 */
import { missingTwilioConfig } from "../src/services/smsService.js";
import { normalizePhoneNumber } from "../src/util/smsPhoneNumber.js";

export const FICTIONAL_PLACEHOLDER = "+15555550123";

export function twilioIsConfigured(): boolean {
  return missingTwilioConfig().length === 0;
}

/**
 * Resolves the destination, or explains why the placeholder cannot be used.
 * Exits rather than spending a round trip discovering it at the provider.
 */
export function resolveTarget(explicit: string | undefined, envVar: string): string {
  const raw = explicit ?? process.env[envVar];
  const normalized = normalizePhoneNumber(raw ?? FICTIONAL_PLACEHOLDER);

  if (normalized === undefined) {
    console.error(`Not a phone number: ${raw}`);
    process.exit(1);
  }

  if (twilioIsConfigured() && normalized === FICTIONAL_PLACEHOLDER) {
    console.error(
      `Twilio is configured, so the destination has to be a number Twilio can\n` +
        `validate. ${FICTIONAL_PLACEHOLDER} is a reserved fictional number and is\n` +
        `rejected with error 21211, even under test credentials.\n\n` +
        `Pass a real number instead — your own is the obvious choice:\n\n` +
        `  ${envVar}=+15551234567 pnpm run <script>\n\n` +
        `Under test credentials nothing is delivered and nothing is charged, so\n` +
        `using your own number here is safe. Under live credentials it is a real\n` +
        `text. Test credentials have their own Account SID: Twilio Console ->\n` +
        `API keys & tokens -> Test credentials.`
    );
    process.exit(1);
  }

  return normalized;
}