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

/* vim:set ts=2 sw=2 et tw=78: */

/* 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/. */

#include "mozilla/dom/ImageData.h"

#include "mozilla/CheckedInt.h"

#include "mozilla/HoldDropJSObjects.h"

#include "mozilla/dom/ImageDataBinding.h"

#include "jsapi.h"

namespace mozilla {

namespace dom {

NS_IMPL_CYCLE_COLLECTING_ADDREF(ImageData)

NS_IMPL_CYCLE_COLLECTING_RELEASE(ImageData)

NS_IMPL_CYCLE_COLLECTION_CLASS(ImageData)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ImageData)

  NS_INTERFACE_MAP_ENTRY(nsISupports)

NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(ImageData)

  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mData)

NS_IMPL_CYCLE_COLLECTION_TRACE_END

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(ImageData)

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(ImageData)

  tmp->DropData();

NS_IMPL_CYCLE_COLLECTION_UNLINK_END

//static

already_AddRefed<ImageData>

ImageData::Constructor(const GlobalObject& aGlobal,

                       const uint32_t aWidth,

                       const uint32_t aHeight,

                       ErrorResult& aRv)

{

  if (aWidth == 0 || aHeight == 0) {

    aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);

    return nullptr;

  }

  CheckedInt<uint32_t> length = CheckedInt<uint32_t>(aWidth) * aHeight * 4;

  if (!length.isValid()) {

    aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);

    return nullptr;

  }

  js::AssertSameCompartment(aGlobal.Context(), aGlobal.Get());

  JSObject* data = Uint8ClampedArray::Create(aGlobal.Context(),

                                             length.value());

  if (!data) {

    aRv.Throw(NS_ERROR_OUT_OF_MEMORY);

    return nullptr;

  }

  RefPtr<ImageData> imageData = new ImageData(aWidth, aHeight, *data);

  return imageData.forget();

}

//static

already_AddRefed<ImageData>

ImageData::Constructor(const GlobalObject& aGlobal,

                       const Uint8ClampedArray& aData,

                       const uint32_t aWidth,

                       const Optional<uint32_t>& aHeight,

                       ErrorResult& aRv)

{

  aData.ComputeLengthAndData();

  uint32_t length = aData.Length();

  if (length == 0 || length % 4) {

    aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);

    return nullptr;

  }

  length /= 4;

  if (aWidth == 0) {

    aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);

    return nullptr;

  }

  uint32_t height = length / aWidth;

  if (length != aWidth * height ||

      (aHeight.WasPassed() && aHeight.Value() != height)) {

    aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);

    return nullptr;

  }

  if (JS_GetTypedArraySharedness(aData.Obj())) {

    // Throw if the object is mapping shared memory (must opt in).

    aRv.ThrowTypeError<MSG_TYPEDARRAY_IS_SHARED>(NS_LITERAL_STRING("Argument of ImageData constructor"));

    return nullptr;

  }

  RefPtr<ImageData> imageData = new ImageData(aWidth, height, *aData.Obj());

  return imageData.forget();

}

void

ImageData::HoldData()

{

  mozilla::HoldJSObjects(this);

}

void

ImageData::DropData()

{

  if (mData) {

    mData = nullptr;

    mozilla::DropJSObjects(this);

  }

}

bool

ImageData::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto, JS::MutableHandle<JSObject*> aReflector)

{

  return ImageData_Binding::Wrap(aCx, this, aGivenProto, aReflector);

}

} // namespace dom

} // namespace mozilla