/*
 * Copyright (C) 2016-2017 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#pragma once

#if ENABLE(WEBASSEMBLY)

#include "ArrayBuffer.h"
#include "MemoryMode.h"
#include "PageCount.h"

#include <wtf/CagedPtr.h>
#include <wtf/Expected.h>
#include <wtf/Function.h>
#include <wtf/RefCounted.h>
#include <wtf/RefPtr.h>
#include <wtf/ThreadSafeWeakPtr.h>
#include <wtf/Vector.h>

namespace WTF {
class PrintStream;
}

namespace JSC {

class LLIntOffsetsExtractor;

namespace Wasm {

class Instance;

class Memory final : public RefCounted<Memory> {
    WTF_MAKE_NONCOPYABLE(Memory);
    WTF_MAKE_FAST_ALLOCATED;
    friend LLIntOffsetsExtractor;
public:
    void dump(WTF::PrintStream&) const;

    explicit operator bool() const { return !!m_handle->memory(); }
    
    enum NotifyPressure { NotifyPressureTag };
    enum SyncTryToReclaim { SyncTryToReclaimTag };
    enum GrowSuccess { GrowSuccessTag };

    static Ref<Memory> create();
    JS_EXPORT_PRIVATE static Ref<Memory> create(Ref<BufferMemoryHandle>&&, WTF::Function<void(GrowSuccess, PageCount, PageCount)>&& growSuccessCallback);
    JS_EXPORT_PRIVATE static Ref<Memory> create(Ref<SharedArrayBufferContents>&&, WTF::Function<void(GrowSuccess, PageCount, PageCount)>&& growSuccessCallback);
    JS_EXPORT_PRIVATE static Ref<Memory> createZeroSized(MemorySharingMode, WTF::Function<void(GrowSuccess, PageCount, PageCount)>&& growSuccessCallback);
    static RefPtr<Memory> tryCreate(VM&, PageCount initial, PageCount maximum, MemorySharingMode, WTF::Function<void(GrowSuccess, PageCount, PageCount)>&& growSuccessCallback);

    JS_EXPORT_PRIVATE ~Memory();

#if ENABLE(WEBASSEMBLY_SIGNALING_MEMORY)
    static size_t fastMappedRedzoneBytes() { return BufferMemoryHandle::fastMappedRedzoneBytes(); }
    static size_t fastMappedBytes() { return BufferMemoryHandle::fastMappedBytes(); } // Includes redzone.
#else
#endif
    static bool addressIsInGrowableOrFastMemory(void*);

    void* memory() const { return m_handle->memory(); }
    size_t size() const { return m_handle->size(); }
    size_t mappedCapacity() const { return m_handle->mappedCapacity(); }
    PageCount initial() const { return m_handle->initial(); }
    PageCount maximum() const { return m_handle->maximum(); }
    BufferMemoryHandle& handle() { return m_handle.get(); }

    MemorySharingMode sharingMode() const { return m_handle->sharingMode(); }
    MemoryMode mode() const { return m_handle->mode(); }

    Expected<PageCount, GrowFailReason> grow(VM&, PageCount);
    bool fill(uint32_t, uint8_t, uint32_t);
    bool copy(uint32_t, uint32_t, uint32_t);
    bool init(uint32_t, const uint8_t*, uint32_t);

    void registerInstance(Instance&);

    void check() {  ASSERT(!deletionHasBegun()); }

    static ptrdiff_t offsetOfHandle() { return OBJECT_OFFSETOF(Memory, m_handle); }

    SharedArrayBufferContents* shared() const { return m_shared.get(); }

private:
    Memory();
    Memory(Ref<BufferMemoryHandle>&&, WTF::Function<void(GrowSuccess, PageCount, PageCount)>&& growSuccessCallback);
    Memory(Ref<BufferMemoryHandle>&&, Ref<SharedArrayBufferContents>&&, WTF::Function<void(GrowSuccess, PageCount, PageCount)>&& growSuccessCallback);
    Memory(PageCount initial, PageCount maximum, MemorySharingMode, WTF::Function<void(GrowSuccess, PageCount, PageCount)>&& growSuccessCallback);

    Expected<PageCount, GrowFailReason> growShared(VM&, PageCount);

    Ref<BufferMemoryHandle> m_handle;
    RefPtr<SharedArrayBufferContents> m_shared;
    WTF::Function<void(GrowSuccess, PageCount, PageCount)> m_growSuccessCallback;
    Vector<ThreadSafeWeakPtr<Instance>> m_instances;
};

} } // namespace JSC::Wasm

#else

namespace JSC { namespace Wasm {

class Memory {
public:
    static bool addressIsInGrowableOrFastMemory(void*) { return false; }
};

} } // namespace JSC::Wasm

#endif // ENABLE(WEBASSEMBLY)
