import path from "path";
import grabDirNames from "../data/grab-dir-names";
import { type BunMariaDBConfig } from "../types";
import { SQL } from "bun";

type Params = {
    config: BunMariaDBConfig;
};

/** Reuse one client per database name to avoid exhausting MariaDB connections. */
const clientCache = new Map<string, Bun.SQL>();

export default function grabMariaDBClient({
    config,
}: Params): Bun.SQL | undefined {
    const cacheKey = config.db_name || "__default__";

    const cached = clientCache.get(cacheKey);
    if (cached) {
        return cached;
    }

    // Prefer the process-wide client when it matches the requested database
    if (
        global.MARIADB_CLIENT &&
        (!global.CONFIG?.db_name || global.CONFIG.db_name === config.db_name)
    ) {
        clientCache.set(cacheKey, global.MARIADB_CLIENT);
        return global.MARIADB_CLIENT;
    }

    const { ROOT_DIR } = grabDirNames();

    try {
        const tls = config.ssl_ca
            ? {
                  ca: Bun.file(path.resolve(ROOT_DIR, config.ssl_ca)),
                  rejectUnauthorized: false,
              }
            : {
                  rejectUnauthorized: false,
              };

        const MariaDBClient = new SQL({
            hostname: process.env.BUN_MARIADB_SERVER_HOST,
            username: process.env.BUN_MARIADB_SERVER_USERNAME,
            password: process.env.BUN_MARIADB_SERVER_PASSWORD,
            database: config.db_name,
            port: process.env.BUN_MARIADB_SERVER_PORT
                ? Number(process.env.BUN_MARIADB_SERVER_PORT)
                : undefined,
            ...config.db_config,
            tls,
            adapter: "mariadb",
        } as Bun.SQL.Options);

        clientCache.set(cacheKey, MariaDBClient);
        return MariaDBClient;
    } catch (error: any) {
        console.error(`Couldn't grab MariaDB Client => ` + error.message);
        return;
    }
}