import { Pool } from 'pg';

/**
 * A dictionary of string keys and generic values. Consider using it instead of `any`.
 */
export interface Dict<T> {
  [key: string]: T;
}

/**
 * An interface that represents a logger implementation to be used by components of `@axinom/mosaic-db-common`. An example of Mosaic implementation:
 * ```ts
 * import { Logger } from '@axinom/mosaic-service-common';
 * //...
 * const logger = new Logger({ context: 'messaging' });
 * ```
 */
export interface DbLogger {
  trace(message: string): void;
  debug(message: string): void;
  debug(error: Error): void;
  error(message: string): void;
  error(error: Error): void;
  error(error: Error, message: string): void;
  log(message: string): void;
  warn(message: string): void;
}

/**
 * An interface that represents a middleware object to be used to register messaging actions that are executed on app shutdown, e.g. PostgreSQL pool shutdown.
 * An example of Mosaic implementation:
 * ```ts
 * import { setupShutdownActions, Logger } from '@axinom/mosaic-service-common';
 * //...
 * const shutdownActions = setupShutdownActions(app, logger);
 * ```
 */
export interface DbShutdownActions {
  push(action: () => void | Promise<void>): void;
}

/**
 * An abstract type extending PostgreSQL Pool. All labelled pool types extend
 * pg.Pool but labelled pool types are not interchangeable so typescript can be
 * leveraged to ensure the correct pool type is being used in a given context.
 */
export type LabelledPgPool<T extends string> = Pool & { label: T };

/**
 * Default labelled pool types
 */
export type OwnerPgPool = LabelledPgPool<'Owner'>;
export type EnvOwnerPgPool = LabelledPgPool<'EnvOwner'>;
export type LoginPgPool = LabelledPgPool<'Login'>;