const DEFAULT_API_BASE_URL = process.env.NODE_ENV === "production"
  ? "https://asnannp-docdoeai.hf.space"
  : "http://127.0.0.1:8000";
const DEFAULT_API_TIMEOUT_MS = 30000;
const DEFAULT_POLL_INTERVAL_MS = 5000;

const publicEnv = {
  NEXT_PUBLIC_API_BASE_URL: process.env.NEXT_PUBLIC_API_BASE_URL,
  NEXT_PUBLIC_API_URL: process.env.NEXT_PUBLIC_API_URL,
  NEXT_PUBLIC_API_TIMEOUT_MS: process.env.NEXT_PUBLIC_API_TIMEOUT_MS,
  NEXT_PUBLIC_POLL_INTERVAL_MS: process.env.NEXT_PUBLIC_POLL_INTERVAL_MS,
  NEXT_PUBLIC_DEMO_MODE: process.env.NEXT_PUBLIC_DEMO_MODE,
} as const;

function readPublicEnv(name: keyof typeof publicEnv) {
  return publicEnv[name]?.trim();
}

export function getPublicApiBaseUrl() {
  const configured =
    readPublicEnv("NEXT_PUBLIC_API_BASE_URL") ||
    readPublicEnv("NEXT_PUBLIC_API_URL") ||
    DEFAULT_API_BASE_URL;

  return configured.replace(/\/$/, "");
}

export function getPublicApiTimeoutMs() {
  const configured = Number(readPublicEnv("NEXT_PUBLIC_API_TIMEOUT_MS"));
  return Number.isFinite(configured) && configured > 0 ? configured : DEFAULT_API_TIMEOUT_MS;
}

export function getPublicPollIntervalMs() {
  const configured = Number(readPublicEnv("NEXT_PUBLIC_POLL_INTERVAL_MS"));
  return Number.isFinite(configured) && configured > 0 ? configured : DEFAULT_POLL_INTERVAL_MS;
}

export type PublicDemoMode = "demo" | "live" | "auto";

/** Resolves NEXT_PUBLIC_DEMO_MODE for API + auth behavior (demo / live / auto). */
export function getPublicDemoMode(): PublicDemoMode {
  const configured = readPublicEnv("NEXT_PUBLIC_DEMO_MODE")?.toLowerCase();

  if (configured === "demo" || configured === "explicit") {
    return "demo";
  }
  if (configured === "live" || configured === "false") {
    return "live";
  }
  if (configured === "auto") {
    return "auto";
  }

  return process.env.NODE_ENV === "production" ? "live" : "auto";
}