import postgres from "postgres";

// Lazy, env-guarded Postgres client. Works with Vercel Postgres (POSTGRES_URL)
// or any DATABASE_URL. Returns null when no DB is configured so the app still
// builds/runs (with in-memory fallback) before storage is provisioned.
let _sql: ReturnType<typeof postgres> | null = null;

export function dbUrl(): string | undefined {
  return process.env.DATABASE_URL || process.env.POSTGRES_URL || process.env.POSTGRES_PRISMA_URL;
}

export function hasDb(): boolean {
  return Boolean(dbUrl());
}

export function getSql() {
  const url = dbUrl();
  if (!url) return null;
  if (!_sql) {
    _sql = postgres(url, { prepare: false, idle_timeout: 20, max: 5, ssl: "require" });
  }
  return _sql;
}