/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* 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/. */

#pragma once

#include "nsCycleCollectionParticipant.h"

#include "nsWrapperCache.h"

#include "mozilla/dom/SVGPointBinding.h"

#include "DOMSVGPointList.h"

// {d6b6c440-af8d-40ee-856b-02a317cab275}

#define MOZILLA_NSISVGPOINT_IID \

  { 0xd6b6c440, 0xaf8d, 0x40ee, \

    { 0x85, 0x6b, 0x02, 0xa3, 0x17, 0xca, 0xb2, 0x75 } }

#define MOZ_SVG_LIST_INDEX_BIT_COUNT 29

namespace mozilla {

namespace dom {

class SVGMatrix;

} // namespace dom

/**

 * Class nsISVGPoint

 *

 * This class creates the DOM objects that wrap internal SVGPoint objects.

 * An nsISVGPoint can be either a DOMSVGPoint or a DOMSVGTranslatePoint

 */

class nsISVGPoint : public nsISupports,

                    public nsWrapperCache

{

public:

  NS_DECLARE_STATIC_IID_ACCESSOR(MOZILLA_NSISVGPOINT_IID)

  NS_DECL_CYCLE_COLLECTING_ISUPPORTS

  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(nsISVGPoint)

  /**

   * Generic ctor for DOMSVGPoint objects that are created for an attribute.

   */

  explicit nsISVGPoint()

    : mList(nullptr)

    , mListIndex(0)

    , mIsReadonly(false)

    , mIsAnimValItem(false)

    , mIsTranslatePoint(false)

  {

  }

  explicit nsISVGPoint(SVGPoint* aPt, bool aIsTranslatePoint)

    : mList(nullptr)

    , mListIndex(0)

    , mIsReadonly(false)

    , mIsAnimValItem(false)

    , mIsTranslatePoint(aIsTranslatePoint)

  {

    mPt.mX = aPt->GetX();

    mPt.mY = aPt->GetY();

  }

protected:

  virtual ~nsISVGPoint()

  {

    // Our mList's weak ref to us must be nulled out when we die. If GC has

    // unlinked us using the cycle collector code, then that has already

    // happened, and mList is null.

    if (mList) {

      mList->mItems[mListIndex] = nullptr;

    }

  }

public:

  /**

   * Creates an unowned copy of this object's point as a DOMSVGPoint.

   */

  virtual DOMSVGPoint* Copy() = 0;

  SVGPoint ToSVGPoint() const {

    return HasOwner() ? const_cast<nsISVGPoint*>(this)->InternalItem() : mPt;

  }

  bool IsInList() const {

    return !!mList;

  }

  /**

   * In future, if this class is used for non-list points, this will be

   * different to IsInList(). "Owner" here means that the instance has an

   * internal counterpart from which it gets its values. (A better name may

   * be HasWrappee().)

   */

  bool HasOwner() const {

    return !!mList;

  }

  bool IsTranslatePoint() const {

    return mIsTranslatePoint;

  }

  /**

   * This method is called to notify this DOM object that it is being inserted

   * into a list, and give it the information it needs as a result.

   *

   * This object MUST NOT already belong to a list when this method is called.

   * That's not to say that script can't move these DOM objects between

   * lists - it can - it's just that the logic to handle that (and send out

   * the necessary notifications) is located elsewhere (in DOMSVGPointList).)

   */

  void InsertingIntoList(DOMSVGPointList *aList,

                         uint32_t aListIndex,

                         bool aIsAnimValItem);

  static uint32_t MaxListIndex() {

    return (1U << MOZ_SVG_LIST_INDEX_BIT_COUNT) - 1;

  }

  /// This method is called to notify this object that its list index changed.

  void UpdateListIndex(uint32_t aListIndex) {

    mListIndex = aListIndex;

  }

  /**

   * This method is called to notify this DOM object that it is about to be

   * removed from its current DOM list so that it can first make a copy of its

   * internal counterpart's values. (If it didn't do this, then it would

   * "lose" its value on being removed.)

   */

  void RemovingFromList();

  bool IsReadonly() const {

    return mIsReadonly;

  }

  void SetReadonly(bool aReadonly) {

    mIsReadonly = aReadonly;

  }

  // WebIDL

  virtual float X() = 0;

  virtual void SetX(float aX, ErrorResult& rv) = 0;

  virtual float Y() = 0;

  virtual void SetY(float aY, ErrorResult& rv) = 0;

  virtual already_AddRefed<nsISVGPoint> MatrixTransform(dom::SVGMatrix& matrix) = 0;

  virtual JSObject* WrapObject(JSContext *cx, JS::Handle<JSObject*> aGivenProto) override

    { return dom::SVGPoint_Binding::Wrap(cx, this, aGivenProto); }

  virtual nsISupports* GetParentObject() = 0;

protected:

#ifdef DEBUG

  bool IndexIsValid();

#endif

  RefPtr<DOMSVGPointList> mList;

  // Bounds for the following are checked in the ctor, so be sure to update

  // that if you change the capacity of any of the following.

  uint32_t mListIndex:MOZ_SVG_LIST_INDEX_BIT_COUNT;

  uint32_t mIsReadonly:1;       // These flags are uint32_t because MSVC won't

  uint32_t mIsAnimValItem:1;    // pack otherwise.

  uint32_t mIsTranslatePoint:1;

  /**

   * Get a reference to the internal SVGPoint list item that this DOM wrapper

   * object currently wraps.

   *

   * To simplify the code we just have this one method for obtaining both

   * baseVal and animVal internal items. This means that animVal items don't

   * get const protection, but then our setter methods guard against changing

   * animVal items.

   */

  SVGPoint& InternalItem();

  // The following member is only used when we're not in a list:

  SVGPoint mPt;

};

NS_DEFINE_STATIC_IID_ACCESSOR(nsISVGPoint, MOZILLA_NSISVGPOINT_IID)

} // namespace mozilla

#undef MOZ_SVG_LIST_INDEX_BIT_COUNT