/* -*- 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/. */

/* code for HTML client-side image maps */

#ifndef nsImageMap_h

#define nsImageMap_h

#include "mozilla/gfx/2D.h"

#include "nsCOMPtr.h"

#include "nsCoord.h"

#include "nsTArray.h"

#include "nsStubMutationObserver.h"

#include "nsIDOMEventListener.h"

class Area;

class nsImageFrame;

class nsIFrame;

class nsIContent;

struct nsRect;

namespace mozilla {

namespace dom {

class HTMLAreaElement;

}

}

class nsImageMap final : public nsStubMutationObserver,

                         public nsIDOMEventListener

{

  typedef mozilla::gfx::DrawTarget DrawTarget;

  typedef mozilla::gfx::ColorPattern ColorPattern;

  typedef mozilla::gfx::StrokeOptions StrokeOptions;

public:

  nsImageMap();

  void Init(nsImageFrame* aImageFrame, nsIContent* aMap);

  /**

   * Return the first area element (in content order) for the given aX,aY pixel

   * coordinate or nullptr if the coordinate is outside all areas.

   */

  nsIContent* GetArea(nscoord aX, nscoord aY) const;

  /**

   * Return area elements count associated with the image map.

   */

  uint32_t AreaCount() const { return mAreas.Length(); }

  /**

   * Return area element at the given index.

   */

  nsIContent* GetAreaAt(uint32_t aIndex) const;

  void Draw(nsIFrame* aFrame, DrawTarget& aDrawTarget,

            const ColorPattern& aColor,

            const StrokeOptions& aStrokeOptions = StrokeOptions());

  /**

   * Called just before the nsImageFrame releases us.

   * Used to break the cycle caused by the DOM listener.

   */

  void Destroy();

  // nsISupports

  NS_DECL_ISUPPORTS

  // nsIMutationObserver

  NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED

  NS_DECL_NSIMUTATIONOBSERVER_CONTENTAPPENDED

  NS_DECL_NSIMUTATIONOBSERVER_CONTENTINSERTED

  NS_DECL_NSIMUTATIONOBSERVER_CONTENTREMOVED

  NS_DECL_NSIMUTATIONOBSERVER_PARENTCHAINCHANGED

  //nsIDOMEventListener

  NS_DECL_NSIDOMEVENTLISTENER

  nsresult GetBoundsForAreaContent(nsIContent *aContent,

                                   nsRect& aBounds);

  using AreaList = AutoTArray<mozilla::UniquePtr<Area>, 8>;

protected:

  virtual ~nsImageMap();

  void FreeAreas();

  void UpdateAreas();

  void SearchForAreas(nsIContent* aParent);

  void AddArea(mozilla::dom::HTMLAreaElement* aArea);

  void AreaRemoved(mozilla::dom::HTMLAreaElement* aArea);

  void MaybeUpdateAreas(nsIContent *aContent);

  nsImageFrame* mImageFrame;  // the frame that owns us

  nsCOMPtr<nsIContent> mMap;

  // almost always has some entries

  AreaList mAreas;

  // This is set when we search for all area children and tells us whether we

  // should consider the whole subtree or just direct children when we get

  // content notifications about changes inside the map subtree.

  bool mConsiderWholeSubtree;

};

#endif /* nsImageMap_h */