/*
 * Copyright (C) 2013-2021 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

#include <wtf/Compiler.h>

WTF_ALLOW_UNSAFE_BUFFER_USAGE_BEGIN

#include "GenericTypedArrayView.h"
#include "JSGlobalObjectInlines.h"

WTF_ALLOW_UNSAFE_BUFFER_USAGE_END

namespace JSC {

template<typename Adaptor>
GenericTypedArrayView<Adaptor>::GenericTypedArrayView(RefPtr<ArrayBuffer>&& buffer, size_t byteOffset, std::optional<size_t> length)
    : ArrayBufferView(Adaptor::typeValue, WTFMove(buffer), byteOffset, length ? std::optional { length.value() * sizeof(typename Adaptor::Type) } : std::nullopt)
{
#if ASSERT_ENABLED
    if (length)
        ASSERT((length.value() / sizeof(typename Adaptor::Type)) < std::numeric_limits<size_t>::max());
#endif
}

template<typename Adaptor>
Ref<GenericTypedArrayView<Adaptor>> GenericTypedArrayView<Adaptor>::create(size_t length)
{
    auto result = tryCreate(length);
    RELEASE_ASSERT(result);
    return result.releaseNonNull();
}

template<typename Adaptor>
Ref<GenericTypedArrayView<Adaptor>> GenericTypedArrayView<Adaptor>::create(
    const typename Adaptor::Type* array, size_t length)
{
    auto result = tryCreate(array, length);
    RELEASE_ASSERT(result);
    return result.releaseNonNull();
}

template<typename Adaptor>
Ref<GenericTypedArrayView<Adaptor>> GenericTypedArrayView<Adaptor>::create(Ref<ArrayBuffer>&& buffer)
{
    auto length = buffer->byteLength();
    return adoptRef(*new GenericTypedArrayView(WTFMove(buffer), 0, length));
}

template<typename Adaptor>
Ref<GenericTypedArrayView<Adaptor>> GenericTypedArrayView<Adaptor>::create(
    RefPtr<ArrayBuffer>&& buffer, size_t byteOffset, std::optional<size_t> length)
{
    auto result = tryCreate(WTFMove(buffer), byteOffset, length);
    RELEASE_ASSERT(result);
    return result.releaseNonNull();
}

template<typename Adaptor>
RefPtr<GenericTypedArrayView<Adaptor>> GenericTypedArrayView<Adaptor>::tryCreate(size_t length)
{
    auto buffer = ArrayBuffer::tryCreate(length, sizeof(typename Adaptor::Type));
    if (!buffer)
        return nullptr;
    return tryCreate(WTFMove(buffer), 0, length);
}

template<typename Adaptor>
RefPtr<GenericTypedArrayView<Adaptor>> GenericTypedArrayView<Adaptor>::tryCreate(
    const typename Adaptor::Type* array, size_t length)
{
    RefPtr<GenericTypedArrayView> result = tryCreate(length);
    if (!result)
        return nullptr;
WTF_ALLOW_UNSAFE_BUFFER_USAGE_BEGIN
    memcpy(result->data(), array, length * sizeof(typename Adaptor::Type));
WTF_ALLOW_UNSAFE_BUFFER_USAGE_END
    return result;
}

template<typename Adaptor>
RefPtr<GenericTypedArrayView<Adaptor>> GenericTypedArrayView<Adaptor>::tryCreate(RefPtr<ArrayBuffer>&& buffer, size_t byteOffset, std::optional<size_t> length)
{
    if (!buffer)
        return nullptr;

    ASSERT(length || buffer->isResizableOrGrowableShared());

    if (!ArrayBufferView::verifySubRangeLength(buffer->byteLength(), byteOffset, length.value_or(0), sizeof(typename Adaptor::Type)))
        return nullptr;

    if (!verifyByteOffsetAlignment(byteOffset, sizeof(typename Adaptor::Type)))
        return nullptr;

    return adoptRef(new GenericTypedArrayView(WTFMove(buffer), byteOffset, length));
}

template<typename Adaptor>
RefPtr<GenericTypedArrayView<Adaptor>> GenericTypedArrayView<Adaptor>::wrappedAs(Ref<ArrayBuffer>&& buffer, size_t byteOffset, std::optional<size_t> length)
{
    ASSERT(length || buffer->isResizableOrGrowableShared());

    // We do not check verifySubRangeLength for resizable buffer case since this function is only called from already created JS TypedArrays.
    // It is possible that verifySubRangeLength fails when underlying ArrayBuffer is resized, but it is OK since it will be just recognized as OOB TypedArray.
    if (!buffer->isResizableOrGrowableShared()) {
        if (!ArrayBufferView::verifySubRangeLength(buffer->byteLength(), byteOffset, length.value_or(0), sizeof(typename Adaptor::Type)))
            return nullptr;
    } else if (buffer->isGrowableShared()) {
        // For growable buffer, we extra-check whether byteOffset and length are within maxByteLength.
        // This does not hit in normal condition, just extra hardening.
        if (!ArrayBufferView::verifySubRangeLength(buffer->maxByteLength().value(), byteOffset, length.value_or(0), sizeof(typename Adaptor::Type)))
            return nullptr;
    }

    if (!verifyByteOffsetAlignment(byteOffset, sizeof(typename Adaptor::Type)))
        return nullptr;

    return adoptRef(*new GenericTypedArrayView(WTFMove(buffer), byteOffset, length));
}

template<typename Adaptor>
Ref<GenericTypedArrayView<Adaptor>>
GenericTypedArrayView<Adaptor>::createUninitialized(size_t length)
{
    auto result = tryCreateUninitialized(length);
    RELEASE_ASSERT(result);
    return result.releaseNonNull();
}

template<typename Adaptor>
RefPtr<GenericTypedArrayView<Adaptor>>
GenericTypedArrayView<Adaptor>::tryCreateUninitialized(size_t length)
{
    RefPtr<ArrayBuffer> buffer =
        ArrayBuffer::tryCreateUninitialized(length, sizeof(typename Adaptor::Type));
    if (!buffer)
        return nullptr;
    return tryCreate(WTFMove(buffer), 0, length);
}

template<typename Adaptor>
JSArrayBufferView* GenericTypedArrayView<Adaptor>::wrapImpl(JSGlobalObject* lexicalGlobalObject, JSGlobalObject* globalObject)
{
    UNUSED_PARAM(lexicalGlobalObject);
    return Adaptor::JSViewType::tryCreate(globalObject, globalObject->typedArrayStructure(Adaptor::typeValue, isResizableOrGrowableShared()), this);
}

} // namespace JSC
