STM.ts

import type { Effect as T } from '@effect-ts/core'
import { pipe } from '@effect-ts/core'
import * as STM from '@effect-ts/core/Effect/Transactional/STM'
import * as TRef from '@effect-ts/core/Effect/Transactional/TRef'

export * from '@effect-ts/core/Effect/Transactional/STM'

export class Gate {
  constructor(readonly ref: TRef.TRef<boolean>) {}

  open = pipe(TRef.getAndSet_(this.ref, true), STM.commit)

  close = pipe(TRef.getAndSet_(this.ref, false), STM.commit)

  waitForOpen: T.Effect<unknown, never, void> = pipe(
    TRef.get(this.ref),
    STM.chain((isOpen) => STM.check(isOpen)),
    STM.commit,
  )

  waitForOpenAndThenClose: T.Effect<unknown, never, void> = pipe(
    TRef.get(this.ref),
    STM.chain((isOpen) => STM.check(isOpen)),
    STM.chain(() => TRef.set_(this.ref, false)),
    STM.commit,
  )

  waitForClose: T.Effect<unknown, never, void> = pipe(
    TRef.get(this.ref),
    STM.chain((isOpen) => STM.check(!isOpen)),
    STM.commit,
  )
}

export const makeGate = (initiallyOpen: boolean): T.Effect<unknown, never, Gate> =>
  pipe(
    TRef.make(initiallyOpen),
    STM.map((ref) => new Gate(ref)),
    STM.commit,
  )