import postgres from "postgres";
import { env } from "./env";

declare global {
  // eslint-disable-next-line no-var
  var __csa_sql: ReturnType<typeof postgres> | undefined;
}

export const sql =
  globalThis.__csa_sql ??
  postgres(env.DATABASE_URL, {
    max: 10,
    idle_timeout: 30,
    connect_timeout: 10,
    transform: { undefined: null },
    types: {
      // numeric → number
      numeric: { to: 1700, from: [1700], serialize: (x: number) => String(x), parse: (x: string) => Number(x) },
    },
  });

if (process.env.NODE_ENV !== "production") globalThis.__csa_sql = sql;

export type Sql = typeof sql;

/** Serialize a number[] for a pgvector column. */
export function vec(v: number[]): string {
  return `[${v.join(",")}]`;
}

export async function getSetting<T = unknown>(key: string, fallback: T): Promise<T> {
  const rows = await sql<{ value: T }[]>`SELECT value FROM settings WHERE key = ${key}`;
  return rows[0]?.value ?? fallback;
}

export async function setSetting(key: string, value: unknown): Promise<void> {
  await sql`INSERT INTO settings (key, value, updated_at) VALUES (${key}, ${sql.json(value as never)}, now())
            ON CONFLICT (key) DO UPDATE SET value = EXCLUDED.value, updated_at = now()`;
}