1// Copyright 2014 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef ReadableStream_h
6#define ReadableStream_h
7
8#include "bindings/core/v8/ScriptPromise.h"
9#include "bindings/core/v8/ScriptPromiseProperty.h"
10#include "bindings/core/v8/ScriptState.h"
11#include "bindings/core/v8/ScriptValue.h"
12#include "bindings/core/v8/ScriptWrappable.h"
13#include "bindings/core/v8/V8Binding.h"
14#include "core/dom/ContextLifecycleObserver.h"
15#include "platform/heap/Handle.h"
16#include "wtf/Forward.h"
17#include "wtf/PassRefPtr.h"
18#include "wtf/RefPtr.h"
19
20namespace blink {
21
22class DOMException;
23class ExceptionState;
24class UnderlyingSource;
25
26class ReadableStream : public GarbageCollectedFinalized<ReadableStream>, public ScriptWrappable {
27    DEFINE_WRAPPERTYPEINFO();
28public:
29    enum State {
30        Readable,
31        Waiting,
32        Closed,
33        Errored,
34    };
35
36    // FIXME: Define Strategy here.
37    // FIXME: Add |strategy| constructor parameter.
38    // After ReadableStream construction, |didSourceStart| must be called when
39    // |source| initialization succeeds and |error| must be called when
40    // |source| initialization fails.
41    ReadableStream(ExecutionContext*, UnderlyingSource* /* source */);
42    virtual ~ReadableStream();
43
44    bool isStarted() const { return m_isStarted; }
45    bool isDraining() const { return m_isDraining; }
46    bool isPulling() const { return m_isPulling; }
47    State state() const { return m_state; }
48    String stateString() const;
49
50    virtual ScriptValue read(ScriptState*, ExceptionState&) = 0;
51    ScriptPromise wait(ScriptState*);
52    ScriptPromise cancel(ScriptState*, ScriptValue reason);
53    ScriptPromise closed(ScriptState*);
54
55    void close();
56    void error(PassRefPtrWillBeRawPtr<DOMException>);
57
58    void didSourceStart();
59
60    virtual void trace(Visitor*);
61
62protected:
63    bool enqueuePreliminaryCheck(size_t chunkSize);
64    bool enqueuePostAction(size_t totalQueueSize);
65    void readPreliminaryCheck(ExceptionState&);
66    void readPostAction();
67
68private:
69    typedef ScriptPromiseProperty<Member<ReadableStream>, V8UndefinedType, RefPtrWillBeMember<DOMException> > WaitPromise;
70    typedef ScriptPromiseProperty<Member<ReadableStream>, V8UndefinedType, RefPtrWillBeMember<DOMException> > ClosedPromise;
71
72    virtual bool isQueueEmpty() const = 0;
73    virtual void clearQueue() = 0;
74
75    void callOrSchedulePull();
76
77    Member<UnderlyingSource> m_source;
78    bool m_isStarted;
79    bool m_isDraining;
80    bool m_isPulling;
81    bool m_isSchedulingPull;
82    State m_state;
83
84    Member<WaitPromise> m_wait;
85    Member<ClosedPromise> m_closed;
86    RefPtrWillBeMember<DOMException> m_exception;
87};
88
89} // namespace blink
90
91#endif // ReadableStream_h
92