import Database from "better-sqlite3";
import { drizzle } from "drizzle-orm/better-sqlite3";
import { mkdirSync } from "node:fs";
import { dirname } from "node:path";
import { getEnv } from "@/lib/env";
import * as schema from "./schema";

const globalForDb = globalThis as unknown as { __bpSqlite?: Database.Database };

function openDatabase(): Database.Database {
  if (globalForDb.__bpSqlite) return globalForDb.__bpSqlite;

  const path = getEnv().DATABASE_PATH;
  mkdirSync(dirname(path), { recursive: true });

  const instance = new Database(path);
  instance.pragma("journal_mode = WAL");
  instance.pragma("foreign_keys = ON");

  // Reused across hot-reloads in dev so we don't leak file handles / open a
  // fresh WAL-mode connection on every request.
  globalForDb.__bpSqlite = instance;
  return instance;
}

// Lazy by design: `next build` imports this module's whole graph while
// collecting route metadata, even for force-dynamic pages that are never
// actually rendered at build time. Opening the DB (and requiring env vars)
// as a module-level side effect would make `pnpm build` fail in CI, where
// no secrets are configured. The proxy defers both until first real query.
export const sqlite = new Proxy({} as Database.Database, {
  get(_target, prop) {
    // drizzle-orm's `isConfig()` probes `.constructor.name` on its first
    // argument to tell a client instance from a plain config object - that
    // introspection must not itself trigger opening the real connection.
    if (prop === "constructor") return Database;
    const instance = openDatabase();
    const value = Reflect.get(instance, prop, instance);
    return typeof value === "function" ? value.bind(instance) : value;
  },
}) as Database.Database;

export const db = drizzle(sqlite, { schema });