import { PostgresConnection, } from './postgres-connection';
import { PostgresQueueBackend } from './postgres-queue-backend';
/**
 * {@link BackendFactory} that builds a {@link PostgresQueueBackend}.
 *
 * The returned backend owns its {@link PostgresConnection} (a `pg.Pool` plus a
 * dedicated `LISTEN` client); the high-level classes depend only on
 * `IQueueBackend` and never touch a `pg` client directly.
 *
 * The `opts.connection` value is forwarded to {@link PostgresConnection} and may
 * be a connection string, a node-postgres pool config (optionally carrying a
 * `schema`), or an already-built `pg.Pool` instance. `pg` is lazily required
 * only when a config/string is passed, so Redis-only users never need it
 * installed.
 *
 * Inject this into the queue classes (or set it as the process-wide default via
 * `setDefaultBackendFactory(createPostgresBackend)`) to back BullMQ with
 * PostgreSQL.
 */
export const createPostgresBackend = (name, opts, factoryOpts = {}) => {
    const connection = new PostgresConnection(opts.connection);
    // Name a backend's dedicated, long-lived connection so it is discoverable via
    // getWorkers / getQueueEvents (pg_stat_activity) — the PostgreSQL analogue of
    // the Redis worker/queue-events named connection. Naming happens eagerly at
    // waitUntilReady (see PostgresQueueBackend) so the name is set as soon as the
    // backend is ready, exactly like Redis names its connection on creation.
    //   - Worker (withBlockingConnection): the bare queue name, or `:w:<name>`
    //     for a named worker — matching the getWorkers matcher.
    //   - QueueEvents (blocking): the queue name + `:qe` (QUEUE_EVENT_SUFFIX),
    //     matching the getQueueEvents matcher. (QueueEvents also re-applies this
    //     via setName when its consume loop starts.)
    // Producers/FlowProducer get no name (they must not be counted as workers).
    const workerName = opts.name;
    let listenClientName;
    if (factoryOpts.withBlockingConnection) {
        listenClientName = `${name}${workerName ? `:w:${workerName}` : ''}`;
    }
    else if (factoryOpts.blocking) {
        listenClientName = `${name}:qe`;
    }
    return new PostgresQueueBackend(connection, name, opts, true, listenClientName);
};