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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim:set ts=2 sw=2 sts=2 et cindent: */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_dom_WritableStream_h

#define mozilla_dom_WritableStream_h

#include "js/TypeDecls.h"

#include "js/Value.h"

#include "mozilla/Attributes.h"

#include "mozilla/ErrorResult.h"

#include "mozilla/dom/BindingDeclarations.h"

#include "mozilla/dom/QueuingStrategyBinding.h"

#include "mozilla/dom/WritableStreamDefaultController.h"

#include "mozilla/dom/WritableStreamDefaultWriter.h"

#include "nsCycleCollectionParticipant.h"

#include "nsWrapperCache.h"

namespace mozilla::dom {

class Promise;

class WritableStreamDefaultController;

class WritableStreamDefaultWriter;

class UnderlyingSinkAlgorithmsBase;

class UniqueMessagePortId;

class MessagePort;

class WritableStream : public nsISupports, public nsWrapperCache {

 public:

  NS_DECL_CYCLE_COLLECTING_ISUPPORTS

  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(WritableStream)

  friend class ReadableStream;

 protected:

  virtual ~WritableStream();

  virtual void LastRelease() {}

  // If one extends WritableStream with another cycle collectable class,

  // calling HoldJSObjects and DropJSObjects should happen using 'this' of

  // that extending class. And in that case Explicit should be passed to the

  // constructor of WriteableStream so that it doesn't make those calls.

  // See also https://bugzilla.mozilla.org/show_bug.cgi?id=1801214.

  enum class HoldDropJSObjectsCaller { Implicit, Explicit };

  explicit WritableStream(const GlobalObject& aGlobal,

                          HoldDropJSObjectsCaller aHoldDropCaller);

  explicit WritableStream(nsIGlobalObject* aGlobal,

                          HoldDropJSObjectsCaller aHoldDropCaller);

 public:

  // Slot Getter/Setters:

  bool Backpressure() const { return mBackpressure; }

  void SetBackpressure(bool aBackpressure) { mBackpressure = aBackpressure; }

  Promise* GetCloseRequest() { return mCloseRequest; }

  void SetCloseRequest(Promise* aRequest) { mCloseRequest = aRequest; }

  MOZ_KNOWN_LIVE WritableStreamDefaultController* Controller() {

    return mController;

  void SetController(WritableStreamDefaultController& aController) {

    MOZ_ASSERT(!mController);

    mController = &aController;

  Promise* GetInFlightWriteRequest() const { return mInFlightWriteRequest; }

  Promise* GetPendingAbortRequestPromise() const {

    return mPendingAbortRequestPromise;

  void SetPendingAbortRequest(Promise* aPromise, JS::Handle<JS::Value> aReason,

                              bool aWasAlreadyErroring) {

    mPendingAbortRequestPromise = aPromise;

    mPendingAbortRequestReason = aReason;

    mPendingAbortRequestWasAlreadyErroring = aWasAlreadyErroring;

  WritableStreamDefaultWriter* GetWriter() const { return mWriter; }

  void SetWriter(WritableStreamDefaultWriter* aWriter) { mWriter = aWriter; }

  enum class WriterState { Writable, Closed, Erroring, Errored };

  WriterState State() const { return mState; }

  void SetState(const WriterState& aState) { mState = aState; }

  JS::Value StoredError() const { return mStoredError; }

  void SetStoredError(JS::Handle<JS::Value> aStoredError) {

    mStoredError = aStoredError;

  void AppendWriteRequest(RefPtr<Promise>& aRequest) {

    mWriteRequests.AppendElement(aRequest);

  // CreateWritableStream

  MOZ_CAN_RUN_SCRIPT static already_AddRefed<WritableStream> CreateAbstract(

      JSContext* aCx, nsIGlobalObject* aGlobal,

      UnderlyingSinkAlgorithmsBase* aAlgorithms, double aHighWaterMark,

      QueuingStrategySize* aSizeAlgorithm, ErrorResult& aRv);

  // WritableStreamCloseQueuedOrInFlight

  bool CloseQueuedOrInFlight() const {

    return mCloseRequest || mInFlightCloseRequest;

  // WritableStreamDealWithRejection

  MOZ_CAN_RUN_SCRIPT void DealWithRejection(JSContext* aCx,

                                            JS::Handle<JS::Value> aError,

                                            ErrorResult& aRv);

  // WritableStreamFinishErroring

  MOZ_CAN_RUN_SCRIPT void FinishErroring(JSContext* aCx, ErrorResult& aRv);

  // WritableStreamFinishInFlightClose

  void FinishInFlightClose();

  // WritableStreamFinishInFlightCloseWithError

  MOZ_CAN_RUN_SCRIPT void FinishInFlightCloseWithError(

      JSContext* aCx, JS::Handle<JS::Value> aError, ErrorResult& aRv);

  // WritableStreamFinishInFlightWrite

  void FinishInFlightWrite();

  // WritableStreamFinishInFlightWriteWithError

  MOZ_CAN_RUN_SCRIPT void FinishInFlightWriteWithError(

      JSContext* aCX, JS::Handle<JS::Value> aError, ErrorResult& aR);

  // WritableStreamHasOperationMarkedInFlight

  bool HasOperationMarkedInFlight() const {

    return mInFlightWriteRequest || mInFlightCloseRequest;

  // WritableStreamMarkCloseRequestInFlight

  void MarkCloseRequestInFlight();

  // WritableStreamMarkFirstWriteRequestInFlight

  void MarkFirstWriteRequestInFlight();

  // WritableStreamRejectCloseAndClosedPromiseIfNeeded

  void RejectCloseAndClosedPromiseIfNeeded();

  // WritableStreamStartErroring

  MOZ_CAN_RUN_SCRIPT void StartErroring(JSContext* aCx,

                                        JS::Handle<JS::Value> aReason,

                                        ErrorResult& aRv);

  // WritableStreamUpdateBackpressure

  void UpdateBackpressure(bool aBackpressure);

  // [Transferable]

  // https://html.spec.whatwg.org/multipage/structured-data.html#transfer-steps

  MOZ_CAN_RUN_SCRIPT bool Transfer(JSContext* aCx,

                                   UniqueMessagePortId& aPortId);

  // https://html.spec.whatwg.org/multipage/structured-data.html#transfer-receiving-steps

  MOZ_CAN_RUN_SCRIPT static already_AddRefed<WritableStream>

  ReceiveTransferImpl(JSContext* aCx, nsIGlobalObject* aGlobal,

                      MessagePort& aPort);

  MOZ_CAN_RUN_SCRIPT static bool ReceiveTransfer(

      JSContext* aCx, nsIGlobalObject* aGlobal, MessagePort& aPort,

      JS::MutableHandle<JSObject*> aReturnObject);

  // Public functions to implement other specs

  // https://streams.spec.whatwg.org/#other-specs-ws

  // https://streams.spec.whatwg.org/#writablestream-set-up

 protected:

  // Sets up the WritableStream. Intended for subclasses.

  void SetUpNative(JSContext* aCx, UnderlyingSinkAlgorithmsWrapper& aAlgorithms,

                   Maybe<double> aHighWaterMark,

                   QueuingStrategySize* aSizeAlgorithm, ErrorResult& aRv);

 public:

  // Creates and sets up a WritableStream. Use SetUpNative for this purpose in

  // subclasses.

  static already_AddRefed<WritableStream> CreateNative(

      JSContext* aCx, nsIGlobalObject& aGlobal,

      UnderlyingSinkAlgorithmsWrapper& aAlgorithms,

      Maybe<double> aHighWaterMark, QueuingStrategySize* aSizeAlgorithm,

      ErrorResult& aRv);

  // The following definitions must only be used on WritableStream instances

  // initialized via the above set up algorithm:

  // https://streams.spec.whatwg.org/#writablestream-error

  MOZ_CAN_RUN_SCRIPT void ErrorNative(JSContext* aCx,

                                      JS::Handle<JS::Value> aError,

                                      ErrorResult& aRv);

  // IDL layer functions

  nsIGlobalObject* GetParentObject() const { return mGlobal; }

  JSObject* WrapObject(JSContext* aCx,

                       JS::Handle<JSObject*> aGivenProto) override;

  // IDL methods

  // TODO: Use MOZ_CAN_RUN_SCRIPT when IDL constructors can use it (bug 1749042)

  MOZ_CAN_RUN_SCRIPT_BOUNDARY static already_AddRefed<WritableStream>

  Constructor(const GlobalObject& aGlobal,

              const Optional<JS::Handle<JSObject*>>& aUnderlyingSink,

              const QueuingStrategy& aStrategy, ErrorResult& aRv);

  bool Locked() const { return !!mWriter; }

  MOZ_CAN_RUN_SCRIPT already_AddRefed<Promise> Abort(

      JSContext* cx, JS::Handle<JS::Value> aReason, ErrorResult& aRv);

  MOZ_CAN_RUN_SCRIPT already_AddRefed<Promise> Close(JSContext* aCx,

                                                     ErrorResult& aRv);

  already_AddRefed<WritableStreamDefaultWriter> GetWriter(ErrorResult& aRv);

 protected:

  nsCOMPtr<nsIGlobalObject> mGlobal;

  // Internal Slots:

 private:

  bool mBackpressure = false;

  RefPtr<Promise> mCloseRequest;

  RefPtr<WritableStreamDefaultController> mController;

  RefPtr<Promise> mInFlightWriteRequest;

  RefPtr<Promise> mInFlightCloseRequest;

  // We inline all members of [[pendingAbortRequest]] in this class.

  // The absence (i.e. undefined) of the [[pendingAbortRequest]]

  // is indicated by mPendingAbortRequestPromise = nullptr.

  RefPtr<Promise> mPendingAbortRequestPromise;

  JS::Heap<JS::Value> mPendingAbortRequestReason;

  bool mPendingAbortRequestWasAlreadyErroring = false;

  WriterState mState = WriterState::Writable;

  JS::Heap<JS::Value> mStoredError;

  RefPtr<WritableStreamDefaultWriter> mWriter;

  nsTArray<RefPtr<Promise>> mWriteRequests;

  HoldDropJSObjectsCaller mHoldDropCaller;

};

namespace streams_abstract {

inline bool IsWritableStreamLocked(WritableStream* aStream) {

  return aStream->Locked();

MOZ_CAN_RUN_SCRIPT already_AddRefed<Promise> WritableStreamAbort(

    JSContext* aCx, WritableStream* aStream, JS::Handle<JS::Value> aReason,

    ErrorResult& aRv);

MOZ_CAN_RUN_SCRIPT already_AddRefed<Promise> WritableStreamClose(

    JSContext* aCx, WritableStream* aStream, ErrorResult& aRv);

already_AddRefed<Promise> WritableStreamAddWriteRequest(

    WritableStream* aStream);

already_AddRefed<WritableStreamDefaultWriter>

AcquireWritableStreamDefaultWriter(WritableStream* aStream, ErrorResult& aRv);

}  // namespace streams_abstract

}  // namespace mozilla::dom

#endif  // mozilla_dom_WritableStream_h