declare const bounded: <A>(requestedCapacity: number) => STM.STM<TQueue<A>>

declare const dropping: <A>(requestedCapacity: number) => STM.STM<TQueue<A>>

declare const sliding: <A>(requestedCapacity: number) => STM.STM<TQueue<A>>

declare const unbounded: <A>() => STM.STM<TQueue<A>>

declare const capacity: <A>(self: TDequeue<A> | TEnqueue<A>) => number

declare const isEmpty: <A>(self: TDequeue<A> | TEnqueue<A>) => STM.STM<boolean>

declare const isFull: <A>(self: TDequeue<A> | TEnqueue<A>) => STM.STM<boolean>

declare const isShutdown: <A>(self: TDequeue<A> | TEnqueue<A>) => STM.STM<boolean>

declare const peek: <A>(self: TDequeue<A>) => STM.STM<A>

declare const peekOption: <A>(self: TDequeue<A>) => STM.STM<Option.Option<A>>

declare const poll: <A>(self: TDequeue<A>) => STM.STM<Option.Option<A>>

declare const size: <A>(self: TDequeue<A> | TEnqueue<A>) => STM.STM<number>

export interface BaseTQueue {
  /**
   * Returns the number of elements the queue can hold.
   */
  capacity(): number

  /**
   * Retrieves the size of the queue, which is equal to the number of elements
   * in the queue. This may be negative if fibers are suspended waiting for
   * elements to be added to the queue.
   */
  readonly size: STM.STM<number>

  /**
   * Returns `true` if the `TQueue` contains at least one element, `false`
   * otherwise.
   */
  readonly isFull: STM.STM<boolean>

  /**
   * Returns `true` if the `TQueue` contains zero elements, `false` otherwise.
   */
  readonly isEmpty: STM.STM<boolean>

  /**
   * Interrupts any fibers that are suspended on `offer` or `take`. Future calls
   * to `offer*` and `take*` will be interrupted immediately.
   */
  readonly shutdown: STM.STM<void>

  /**
   * Returns `true` if `shutdown` has been called, otherwise returns `false`.
   */
  readonly isShutdown: STM.STM<boolean>

  /**
   * Waits until the queue is shutdown. The `STM` returned by this method will
   * not resume until the queue has been shutdown. If the queue is already
   * shutdown, the `STM` will resume right away.
   */
  readonly awaitShutdown: STM.STM<void>
}

export interface TDequeue<out A> extends TQueue.TDequeueVariance<A>, BaseTQueue {
  /**
   * Views the next element in the queue without removing it, retrying if the
   * queue is empty.
   */
  readonly peek: STM.STM<A>

  /**
   * Views the next element in the queue without removing it, returning `None`
   * if the queue is empty.
   */
  readonly peekOption: STM.STM<Option.Option<A>>

  /**
   * Takes the oldest value in the queue. If the queue is empty, this will return
   * a computation that resumes when an item has been added to the queue.
   */
  readonly take: STM.STM<A>

  /**
   * Takes all the values in the queue and returns the values. If the queue is
   * empty returns an empty collection.
   */
  readonly takeAll: STM.STM<Array<A>>

  /**
   * Takes up to max number of values from the queue.
   */
  takeUpTo(max: number): STM.STM<Array<A>>
}

export interface TEnqueue<in A> extends TQueue.TEnqueueVariance<A>, BaseTQueue {
  /**
   * Places one value in the queue.
   */
  offer(value: A): STM.STM<boolean>

  /**
   * For Bounded TQueue: uses the `BackPressure` Strategy, places the values in
   * the queue and always returns true. If the queue has reached capacity, then
   * the fiber performing the `offerAll` will be suspended until there is room
   * in the queue.
   *
   * For Unbounded TQueue: Places all values in the queue and returns true.
   *
   * For Sliding TQueue: uses `Sliding` Strategy If there is room in the queue,
   * it places the values otherwise it removes the old elements and enqueues the
   * new ones. Always returns true.
   *
   * For Dropping TQueue: uses `Dropping` Strategy, It places the values in the
   * queue but if there is no room it will not enqueue them and return false.
   */
  offerAll(iterable: Iterable<A>): STM.STM<boolean>
}

export interface TQueue<in out A> extends TEnqueue<A>, TDequeue<A> {}

declare const awaitShutdown: <A>(self: TDequeue<A> | TEnqueue<A>) => STM.STM<void>

declare const offer: {
  <A>(value: A): (self: TEnqueue<A>) => STM.STM<void>
  <A>(self: TEnqueue<A>, value: A): STM.STM<void>
}

declare const offerAll: {
  <A>(iterable: Iterable<A>): (self: TEnqueue<A>) => STM.STM<boolean>
  <A>(self: TEnqueue<A>, iterable: Iterable<A>): STM.STM<boolean>
}

declare const seek: {
  <A>(predicate: Predicate<A>): (self: TDequeue<A>) => STM.STM<A>
  <A>(self: TDequeue<A>, predicate: Predicate<A>): STM.STM<A>
}

declare const shutdown: <A>(self: TDequeue<A> | TEnqueue<A>) => STM.STM<void>

declare const take: <A>(self: TDequeue<A>) => STM.STM<A>

declare const takeAll: <A>(self: TDequeue<A>) => STM.STM<Array<A>>

declare const takeBetween: {
  (min: number, max: number): <A>(self: TDequeue<A>) => STM.STM<Array<A>>
  <A>(self: TDequeue<A>, min: number, max: number): STM.STM<Array<A>>
}

declare const takeN: {
  (n: number): <A>(self: TDequeue<A>) => STM.STM<Array<A>>
  <A>(self: TDequeue<A>, n: number): STM.STM<Array<A>>
}

declare const takeUpTo: {
  (max: number): <A>(self: TDequeue<A>) => STM.STM<Array<A>>
  <A>(self: TDequeue<A>, max: number): STM.STM<Array<A>>
}

declare const isTDequeue: (u: unknown) => u is TDequeue<unknown>

declare const isTEnqueue: (u: unknown) => u is TEnqueue<unknown>

declare const isTQueue: (u: unknown) => u is TQueue<unknown>

declare const TDequeueTypeId: unique symbol

type TDequeueTypeId = typeof TDequeueTypeId

declare const TEnqueueTypeId: unique symbol

type TEnqueueTypeId = typeof TEnqueueTypeId

export interface TEnqueueVariance<in A> {
  readonly [TEnqueueTypeId]: {
    readonly _In: Types.Contravariant<A>
  }
}

export interface TDequeueVariance<out A> {
  readonly [TDequeueTypeId]: {
    readonly _Out: Types.Covariant<A>
  }
}