/* -*- 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/. */

#ifndef mozilla_dom_SVGMPathElement_h

#define mozilla_dom_SVGMPathElement_h

#include "mozilla/dom/IDTracker.h"

#include "nsSVGElement.h"

#include "nsStubMutationObserver.h"

#include "nsSVGString.h"

nsresult NS_NewSVGMPathElement(nsIContent **aResult,

                               already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo);

typedef nsSVGElement SVGMPathElementBase;

namespace mozilla {

namespace dom {

class SVGPathElement;

class SVGMPathElement final : public SVGMPathElementBase,

                              public nsStubMutationObserver

{

protected:

  friend nsresult (::NS_NewSVGMPathElement(nsIContent **aResult,

                                           already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo));

  explicit SVGMPathElement(already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo);

  ~SVGMPathElement();

  virtual JSObject* WrapNode(JSContext *aCx, JS::Handle<JSObject*> aGivenProto) override;

public:

  // interfaces:

  NS_DECL_ISUPPORTS_INHERITED

  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(SVGMPathElement,

                                           SVGMPathElementBase)

  NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED

  // nsIContent interface

  virtual nsresult Clone(dom::NodeInfo*, nsINode** aResult) const override;

  virtual nsresult BindToTree(nsIDocument* aDocument, nsIContent* aParent,

                              nsIContent* aBindingParent) override;

  virtual void UnbindFromTree(bool aDeep, bool aNullParent) override;

  // Element specializations

  virtual bool ParseAttribute(int32_t aNamespaceID,

                                nsAtom* aAttribute,

                                const nsAString& aValue,

                                nsIPrincipal* aMaybeScriptedPrincipal,

                                nsAttrValue& aResult) override;

  virtual nsresult AfterSetAttr(int32_t aNamespaceID, nsAtom* aName,

                                const nsAttrValue* aValue,

                                const nsAttrValue* aOldValue,

                                nsIPrincipal* aMaybeScriptedPrincipal,

                                bool aNotify) override;

  // Public helper method: If our xlink:href attribute links to a <path>

  // element, this method returns a pointer to that element. Otherwise,

  // this returns nullptr.

  SVGPathElement* GetReferencedPath();

  // WebIDL

  already_AddRefed<SVGAnimatedString> Href();

protected:

  /**

   * Helper that provides a reference to the 'path' element with the ID that is

   * referenced by the 'mpath' element's 'href' attribute, and that will

   * invalidate the parent of the 'mpath' and update mutation observers to the

   * new path element if the element that that ID identifies changes to a

   * different element (or none).

   */

  class PathElementTracker final : public IDTracker {

  public:

    explicit PathElementTracker(SVGMPathElement* aMpathElement)

      : mMpathElement(aMpathElement)

    {}

  protected:

    // We need to be notified when target changes, in order to request a sample

    // (which will clear animation effects that used the old target-path

    // and recompute the animation effects using the new target-path).

    virtual void ElementChanged(Element* aFrom, Element* aTo) override {

      IDTracker::ElementChanged(aFrom, aTo);

      if (aFrom) {

        aFrom->RemoveMutationObserver(mMpathElement);

      }

      if (aTo) {

        aTo->AddMutationObserver(mMpathElement);

      }

      mMpathElement->NotifyParentOfMpathChange(mMpathElement->GetParent());

    }

    // We need to override IsPersistent to get persistent tracking (beyond the

    // first time the target changes)

    virtual bool IsPersistent() override { return true; }

  private:

    SVGMPathElement* const mMpathElement;

  };

  virtual StringAttributesInfo GetStringInfo() override;

  void UpdateHrefTarget(nsIContent* aParent, const nsAString& aHrefStr);

  void UnlinkHrefTarget(bool aNotifyParent);

  void NotifyParentOfMpathChange(nsIContent* aParent);

  enum { HREF, XLINK_HREF };

  nsSVGString        mStringAttributes[2];

  static StringInfo  sStringInfo[2];

  PathElementTracker mPathTracker;

};

} // namespace dom

} // namespace mozilla

#endif // mozilla_dom_SVGMPathElement_h